Byte Magazine Volume 06 Number 02 - The Computer and Voice Synthesis

This book was produced in EPUB format by the Internet Archive.

The book pages were scanned and converted to EPUB format automatically. This process relies on optical character recognition, and is somewhat susceptible to errors. The book may not offer the correct reading sequence, and there may be weird characters, non-words, and incorrect guesses at structure. Some page numbers and headers or footers may remain from the scanned page. The process which identifies images might have found stray marks on the page which are not actually images from the book. The hidden page numbering which may be available to your ereader corresponds to the numbered pages in the print edition, but is not an exact match; page numbers will increment at the same rate as the corresponding print edition, but we may have started numbering before the print book's visible page numbers. The Internet Archive is working to improve the scanning process and resulting books, but in the meantime, we hope that this book will be useful to you.

The Internet Archive was founded in 1996 to build an Internet library and to promote universal access to all knowledge. The Archive's purposes include offering permanent access for researchers, historians, scholars, people with disabilities, and the general public to historical collections that exist in digital format. The Internet Archive includes texts, audio, moving images, and software as well as archived web pages, and provides specialized services for information access for the blind and other persons with disabilities.

Created with abbyy2epub (v.1.7.2)

YOUR CHOICE-smart either way

• Over 140 software driven functions

• 82 x 24 or 82 x 20 screen format — software selectable

• High resolution 7x12 matrix characters — P-31 green phosphor

• Upper/lower case character set — plus graphics character set

• 56-key alphanumeric keyboard — plus 12-key cursor, numeric pad

• Internal editing functions — insert, delete, scroll, roll, slide, etc.

• Parallel printer I/O port

• 50 to 38,400 baud operation — programmable

• Cursor type, cursor position, print control characters, protected fields, shift inversion, dual intensity and many other features

8212 — twelve-inch diagnonal screen or 8209 — nine-inch diagnonal screen

.

SOUTHWEST TECHNICAL PRODUCTS CORPORATION

219 W. RHAPSODY

SAN ANTONIO, TEXAS 78216 (512) 344-0241

Circle 324 on inquiry card.

Gromemco accepts your challenge,

Data General

Yes, Data General, we saw your ad.

So we realize you hope to win over some of our computer business.

And we can see you have reason to be pleased about your line of minicomputers. They are MINIs though.

But Cromemco produces stateof-the-art MICROcomputers.

Powerful ones.

And our micros have some outstanding advantages.

For example, Cromemco is the only microcomputer manufacturer to support a broad range of microcomputers with (a) 5-inch

WE'RE BUSTING THE COMPETITION'S

BOARDS AGAIN.

Announcing MBC/2 and MBC/3, the newest members of Data . General's growing family of microNOVA" board computers. They're the best computers on a board money can buy. You get u p to 64K bytes of memory, serial and parallel I/O lines, and software support from MP/OS, our famous micro operating system. You even get. supporting languages like MP/PASCAL and MP/FORTRAN IV.Seeforyoursell.

• !*■< 5 S.<<^

The competition will always sing the praises of their little single board computer. But from now on they'll be doing it falsetto.

cn

!'^0iSS^'

double-sided, double-density floppy disk drives and with (b) 8-inch double-sided, double-density floppy disk drives AS WELL AS (c) 8-inch Winchester hard disk drives.

That means, of course, that our customers have a wide choice of disk storage capability.

UNEQUALLED SOFTWARE SUPPORT

OK. That was one point.

Here's another: our stunning selection of software support. Cromemco is the only micro manufacturer to produce both single-user and multi-user multitasking computers with software like this:

SYSTEM SOFTWARE

CDOS (a CP/M-like operating

system)

CROMIX (a UNIX-like operating

system)

RPG-II (IBM-compatible)

COBOL

BASIC

FORTRAN IV

RATFOR

LISP

C

Macro Assembler

APPLICATION SOFTWARE

Word Processing System Data-Base Management General Ledger Accounts Receivable Accounts Payable Inventory

All of this is available now with more coming all the time.

So there you are, D.G.

You can see why we know our microcomputers will stand the test.

Cromemco eagerly accepts the challenge.

Cromemco

incorporated

Tomorrow's Computers Today

280 BERNARDO AVE. MOUNTAIN VIEW.CA 94043 (415) 964-7400 • TWX 910-379-6988

Circle 1 on inquiry card.

BYTE February 1981

Management Information Display

Ultrasonic heart sector scan

High-resolution display with alphanumerics

Get the professional color

display that has BASIC/FORTRAN simplicity

LOW-PRICED, TOO

Here's a color display that has everything: professional-level resolution, enormous color range, easy software, NTSC conformance, and low price.

Basically, this new Cromemco Model SDI* is a two-board interface that plugs into any Cromemco computer.

The SDI then maps computer display memory content onto a convenient color monitor to give high-quality, highresolution displays (756 H x 482 V pixels).

When we say the SDI results in a highquality professional display, we mean you can't get higher resolution than this system offers in an NTSC-conforming display.

The resolution surpasses that of a color TV picture.

BASIC/FORTRAN programming

Besides its high resolution and low price, the new SDI lets you control with optional Cromemco software packages that use simple BASIC- and FORTRANlike commands.

Pick any of 16 colors (from a 4096-color palette) with instructions like DEFCLR (c, R, C, B). Or obtain a circle of specified size, location, and color with XCIRC (x, y, r, c).

•U.S. Pat. No. 4121283

Model SDI High-Resolution Color Graphics Interface

HIGH RESOLUTION

The SDI's high resolution gives a professional-quality display that strictly meets NTSC requirements. You get 756 pixels on every visible line of the NTSC standard display of 482 image lines. Vertical line spacing is 1 pixel.

To achieve the high-quality display, a separate output signal is produced for each of the three component colors (red, green, blue). This yields a sharper image than is possible using an NTSC-composite video signal and color TV set. Full image quality is readily realized with our highquality RGB Monitor or any conventional red/green/blue monitor common in TV work.

Model SDI plugs into Z-2H 11-megabyte

hard disk computer or any Cromemco

computer

DISPLAY MEMORY

Along with the SDI we also offer an optional fast and novel two-port memory that gives independent high-speed access to the computer memory. The two-port memory stores one full display, permitting fast computer operation even during display.

CONTACT YOUR REP NOW

The Model SDI has been used in scientific work, engineering, business, TV, color graphics, and other areas. It's a good example of how Cromemco keeps computers in the field up to date, since it turns any Cromemco computer into an up-to-date color display computer.

The SDI has still more features that you should be informed about. So contact your Cromemco representative now and see all that the SDI will do for you.

Circle 1 on inquiry card.

Q

Cromemco

incorporated

280 BERNARDO AVE., MOUNTAIN VIEW, CA 94043 • (415) 964-7400

Tomorrow's computers today

In The Queue

Volume 6, Number 2

February 1981

Features

36 An Extremely Low-Cost Computer Voice Response System by James C Anderson / infinite clipping produces acceptable computer speech.

44 A Computer-Controlled Tank by Steve

Garcia / A wireless remote-control link to a personal computer enhances Milton-Bradley's Big Trak.

68 A Beginner's Guide to Spectral Analysis, Part T by Mark Zimmermann / A nonmathematical treatment of Fourier transforms.

106 A Pascal Library Unit for the Mlcromodem

II by Thomas H Woteki / Pascal routines which allow the Apple to perform mass-transfer and processing of files via the Micromodem II.

142 Dynamic Memory: Making an Intelligent

Decision by Larry Malakoff / Dynamic memory boards can have one-sixth the power and half the space of static types, but these advantages are useless if the board doesn't work.

152 Stacking Strings In FORTH by John

Cassady / A set of "words" for the FORTH vocabulary adds string-handling capabilities to the language.

164 Articulate Automata by Kathryn Fons and

Tim Gargagliano I A look at the physiology of speech and at how the electronic equivalent of the human vocal tract (the voice synthesizer) is programmed.

220 Image Processing With a Printer by Clark A

Calkins / With this simple system a little hardware goes a long way in processing and printing images.

312 A/D and D/A Conversion — An Inexpensive Approach by Roger W Mikel / This fast converter requires a minimum of parts and supplies 8 bits of resolution over a 5 V range.

318 Turn Your COSMAC VIP into a Frequency Counter by Andrew Modla / Display frequencies in the range of I to 1 1,004 Hz on your COSMAC computer.

326 A Heating and Cooling Management System by Tom Hall / How to build a remote temperature sensor.

332 Modifying the SwTPC Computer by Thomas J Weaver / Modifying the SwTPC 6800 computer to accept either the 6800 or 6809 processor board.

Reviews

30 Radio Shack's Daisy Wheel Printer II by Yvon Kolya

96 Infinite BASIC and Infinite Business by Scott Mitchell

202 IRV, a TRS-80 Utility Program by Teri Li 253 The Heath H-I4 Printer by Bradford Rehm 262 Zork, The Great Underground Empire by Bob Liddil

Nucleus

6 Editorial: Computer Speech: An Update

16 Letters

92, 266, 271, 325 Programming Quickies

94, 102, 290, 309 BYTE'S Bits

138, 188, 196, Technical Forum: Recording with Current:

Nonlinearities in Illumination: Build a Null Modem

212 BYTELINES

274 Education Forum: Microcomputers in the Chemistry

Lab

280 Ask BYTE

288 System Notes

289 Software Received 292 Books Received

294 Clubs and Newsletters

298 Event Queue

304 Book Reviews

324 Cartoon

336 What's New?

382 Unclassified Ads

383 BOMB, BOMB Results

384 Reader Service

BYTE

11

■ill i

: ' : : I

jlllfji

■

=;:•:■ — ■ ■ :':■! :

jjjfjjj

il

<

■.-";::::

■

/■■■'•'y.

hiiiii

- =_ E :

iii

iii|ji!

■

fill :

"-=

||||fil

>:' :!. rMrw: l

■

Will!

lillll!

I lilml

= ;"

If Ii|lf 11

; :;-...--.

; '. :

::-.-. .- .

iliiilill

:..-■

Iliiilill

■ -

Ill

iiilHI

1

lifeii

1 \:

Page 30

Page 44

Page 164

Page 220

February 19S1 © BYTE Publications Inc 3

M

Editor in Chief Christopher Morgan

Technical Editors

Richard S Shuford; Gregg Williams:

Curtis P Feigel; Harold Nelson;

Stan Miastkowski; Kevin Cohan; Bruce Roberts;

Charles Freiberg, New Products; Steve Ciarcia,

Mark Dahmke, Consulting Editors

Copy Editors

Richard Friedman. Chief; Faith Hanson; Warren Williamson; Robin M Moss; Anthony J Lockwood

Assistants

Faith Ferry; Debe Wheeler; Karen A Cilley; Jon Swanson

Production

Nancy Estle. Director; Christine Dixon, Asst Director; Wai Chiu Li; Holly Carmen LaBossiere; Deborah Porter; Sherry McCarthy. Chief Typographer; Debi Fredericks; Donna Sweeney; Valerie Horn

Advertising

Thomas Harvey. Director; Ruth M Walsh; Marion Gagnon; Barbara J Greene; Rob Hannings

Circulation

Gregory Spitzfaden, Manager; Andrew Jackson. Asst Manager; Agnes E Perry; Barbara Varnum; Louise Menegus; Melanie Bertoni. Dealer Sales

Marketing

Jill E Callihan, Special Projects; Laura Hanson

Controllers Office

Daniel Rodrigues, Controller; Mary E Fluhr, Asst Controller; Karen Burgess: Jeanne Cilley

Traffic

Mark Sandagata; N Scott Gagnon

Receptionist

Jacqueline Earnshaw

Publishers

Virginia Londoner; Gordon R Williamson; John E Hayes, Associate Publisher: Cheryl A Hurd. Publisher's Assistant

Officers of McGraw-Hill Publications Company: Paul F McPherson, President: Executive Vice Presidents: James E Boddorf, Gene W Simpson; Group Vice President: Daniel A McMillan: Senior Vice President-Editorial: Ralph R Schulz; Vice Presidents: Kemp Anderson, Business Systems Development; Stephen C Croft, Manufacturing; Robert B Doll, Circulation; James E Hackett, Controller; William H Hammond, Communications: Eric B Herr, Planning and Development; John W Patten, Sales; Edward E Schirmer, International.

Officers of the Corporation. Harold W McGraw Jr. President, Chief Executive Officer and Chairman of the Board: Robert F Landes, Senior Vice President and Secretary: Ralph J Webb, Treasurer.

In This Issue

This month we talk about voices — computer voices, that is — and several other topics as well.

Consulting Editor Mark Dahmke speaks out on speech in the editorial "Computer Speech: An Update." We also have two theme articles: "An Extremely Low-Cost Computer Voice Response System," which shows how to computerize your vox humana for very little money, and "Articulate Automata," which looks at the physiology of speech.

Also in this issue is Steve Ciarcia's do-it-yourself computerized Big Trak; everything you've always wanted to know about dynamic memory; inexpensive A/D and D/A conversion; and much more, including reviews of the new Radio Shack Daisy Wheel Printer II, the Heath H-14 printer, not to mention Zork and IRV.

BYTE is published monthly by BYTE Publications Inc. 70 Main St, Peterborough NH 03458. a wholly-owned subsidiary of McGraw-Hill. Inc. Address all mail except subscriptions to above address: phone |603) 924-9281. Address subscriptions, change of address, USPS Form 3579. and fulfillment questions to BYTE Subscriptions. POB 590. Martinsville NJ 08836. Controlled circulation postage paid at Waseca. Minnesota 56093 - USPS Publication No. 528890 (ISSN 0360-5281). Canadian second class registration number 9321. Subscriptions are S19 for one year, S34 for two years, and S49 for three years in the USA and its possessions. In Canada and Mexico, S2I for one year, S38 for two years, S55 for three years. S43 for one year air delivery to Europe. S35 surface delivery elsewhere. Air delivery to selected areas at additional rates upon request. Single copy price is S2.50 in the USA and its possessions. S2.95 in Canada and Mexico, S4.00 in Europe, and 54 50 elsewhere. Foreign subscriptions and sales should be remitted in United States funds drawn on a US bank. Printed in United States of America.

Address all editorial correspondence to the editor at BYTE. POB 372, Hancock NH 03449. Unacceptable manuscripts will be returned if accompanied by sufficient first class postage. Not responsible for lost manuscripts or photos. Opinions expressed by the authors are not necessarily those of BYTE. Entire contents copyright ©I 981 by BYTE Publications Inc. All rights reserved. Where necessary, permission is granted by the copyright owner for libraries and others registered with the Copyright Clearance Center |CCC) to photocopy any article herein for the base fee of S1.00 per copy of the article or item plus 25 cents per page. Payment should be sent directly to the CCC, 21 Congress St, Salem MA 01970. Copying done for other than personal or internal reference use without the permission of McGraw-Hill is prohibited. Requests for special permission or bulk orders should be addressed to the publisher.

BYTE® is available in microform from University Microfilms International, 300 N Zeeb Rd, Dept PR. Ann Arbor Ml 48106 USA or 18 Bedford Row. Dept PR. London WCIR 4EJ England.

Subscription WATS Line: (800) 258-5485 Office hours: Mon-Thur 8:30 AM - 4:30 PM, Friday 8:30 AM - Noon, Eastern Time

NATIONAL ADVERTISING SALES REPRESENTATIVES:

NORTHEAST [617| 444-3946

MIDWEST (312) 864-3467

MID ATLANTIC (212) 682-5844

Hajar Associates

Hajar Associates

Hajar Associates

280 Hillside Ave

2405 Lawndale

521 Fifth Ave

Needham Heights MA 02194

Evanston IL 60201

New York NY 10017

NORTHWEST |4I5| 964-0706

SOUTHWEST (714) 540-3554

SOUTHEAST (305) 886-7210

Hajar Associates

Hajar Associates

Hajar Associates

1000 ElwellCt. Suite 227

3303 Harbor Blvd

1220 Prairie Lane

Palo Alto CA 94303

Suite K-4

Costa Mesa CA 92626

Apopka FL 32703

February 1981 © BYTE Publications Inc

■ COLOR GRAPHICS ■ IT'S HERE

8455-D Tyco Road

Vienna, Virginia 22180

(703) 827-0888

TWX: 710-831-9087

OEM/Dealer inquiries invited

Circle 2 on inquiry card.

Circle 3 on inquiry card.

UCSD

PASCAL FORTRAN

Portable

Develop on a Z-flOt, runonLSI-11%, T.I. 990, 6800 or vice versa

Efficient

Structured, readable Speeds development X5 Easy maintenance

Powerful

Full standard Pascal

plus extensions

ANSI '77 Fortran Subset

Cost Effective

Complete system including interpreter, screen editor, utilities, filer, assembler, and compiler.

with Pascal $350 with Fortran $400 with Both $550

APPLICATIONS PFAS

(Pascal File Access System) Keyed-ISAM in 6 K user memory $200

INTELLECT V1.2

A full range LISP interpreter for UCSD p-systems $200

MEDOFFICE

Professional medical office software for 1 to 5 doctors. Call for pricing.

DATEBOOK

Appointment scheduling on your micro $295

READY TO RUN ON DEC PDP-11 Jor TRS-80 MODEL 11 §

Editorial

PCD

SYSTEMS

P.O. Box 143 PennYan, NY 14527 315-536-3734

*TM Univ. of Calif.

tTMofZilog

+TM of Digital Equipment

§TM of Tandy Corp.

Computer Speech: An Update

Guest Editorial by Mark C Dahmke

In 1972 I saw an advertisement in Scientific American for the Votrax speech synthesizer — a multiple-board system that produced fairly intelligible speech. Although digital speech synthesis has been with us for more than a generation, it wasn't until the early seventies that relatively low cost, compact synthesizers were available for use in industry. At the time, I became very interested in the concept and wanted to experiment with a synthesizer, but the price was still too high for my budget.

Finally, in August 1976, BYTE published an issue on speech synthesis. The article "Friends, Humans, Countryrobots: Lend me your Ears" described in detail the Computalker CT-1 speech synthesizer designed by Computalker

Photo 1: The author of this month's guest editorial, Mark Dahmke (left), demonstrating the special speech-generating computer system, "The Bionic Voice," he developed for his friend Bill Rush. The Computalker-based system allows Bill, a quadriplegic, to "speak" with the aid of a head stick. Mark and Bill were the subjects of a feature story in Life magazine last year that was later condensed in the Reader's Digest. Hollywood is interested, too: a movie is being produced for television that will tell their story and show how personal computers can make a profound difference in people's lives. Mark is a Consulting Editor for BYTE, and has had a continuing interest in computer speech for many years. His forthcoming book, Microcomputer Operating Systems, will be published by BYTE Books later this year....CM (Photo courtesy Brian Lanker).

February 1981 © BYTE Publications lnc

Circle 4 on inquiry card.

TRS-80* Model I Computer Owners . . .

Double-density storage. It's really here!

Here at Percom. And your authorized Percom dealers.

And double-density storage is here in a big way. Because now you can choose from three different levels of mini-disk systems — all double-density rated.

And get the storage that precisely meets your application needs.

Not to mention the service and quality that's made Percom the industry leader.

Although rated for double-density operation, all levels of Percom drives work equally well in singledensity applications.

You can operate these drives in ordinary singledensity format using TRSDOS* Percom OS-80™ or any other single-density operating system.

Or, you can add a Percom DOUBLER™ to your Tandy Expansion Interface and store data and programs in either single- or double-density format.

Under double-density operation, you can store as much as 350 Kbytes of formatted data — depending on the drive model— on one side of a five-inch minidiskette. That's four times the capacity of standard 35-track Model I minidisks, almost 100 Kbytes more than the capacity of the eight-inch IBM 3740 format!

Available in 1-, 2- and 3-drive configurations in all three model lines, Percom burned-in, fullytested drives start at only $399.

Li

TFD-40™ Drives

TFD-40 Drives store 180 Kbytes (double-density) or 102 Kbytes (single-density) of formatted data on one side of a 40-track minidiskette. Although economically priced, TFD-40 drives receive the same full Percom quality control measures as TFD-100 and TFD-200 drives.

TFD-100™ Drives

TFD-100 drives are "flippy" drives. You store twice the data per minidiskette by using both sides of the disk. TFD-100 drives store 180 Kbytes (doubledensity) or 102 Kbytes (single-density) per side. Under double-density operation, you can store a 70page document on one minidiskette.

TFD-200™ Drives

TFD-200 drives store 350 Kbytes (double-density) or 197 Kbytes (single-density) on one side of a minidiskette. By comparison, 3740-formatted eight-inch disks store only 256 Kbytes. Enormous on-line storage capacity in a 5" drive, plus proven Percom reliability. That's what you get in a TFD-200.

_ The DOUBLER™ — This proprietary adapter for the TRS-80* Model I computer packs approximately twice the data on a disk track.

Depending on the type of drive, you can store up to four times as much data — 350 Kbytes — on one side of a minidiskette as you can store using a Tandy standard Model I computer drive.

Easy to install, the DOUBLER merely plugs into the disk controller chip socket of your Expansion Interface. No rewiring. No trace cutting.

And because the DOUBLER reads, writes and formats either single- or double-density disks, you can continue to run all of your single-density software, then switch to double-density operation at any convenient time.

Included with the PC card adapter is a TRSDOS*compatible double-density disk operating system, called DBLDOS™, plus a CONVERT utility that converts files and programs from single- to double-density or double- to single-density format.

Each DOUBLER also includes an on-card highperformance data separator circuit which ensures reliable disk read operation.

The DOUBLER works with standard 35-, 40-, 77- and 80-track drives rated for double-density operation.

Note. Opening the Expansion Interface to install the DOUBLER may void Tandy's limited 90-day warranty.

Free software patch This software patch, called PATCH PAK™, upgrades TRSDOS* for operation with improved 40- and 77track drives. For single-density operation only.

Quality Percom products are available at authorized dealers. Call toll free 1-800-527-1592 for the address of your nearest dealer or to order directly from Percom. In Canada call 519-824-7041.

tv , , „ "■"„ „ . ■;.- - :■ Prices and specifications subject to change without notice,

trademark of Percom Data Company, Inc.

trademark of Tandy Radio Shack Corporation which has no relationship to Percom Data Company

PEflCCM

PEHCOWI DATA COMPANY. INC.

211 N. KIHBY • GABLANDTX • 75042 I214) 272-3421

Editorial _^_^^_^-^^^^^_

Consultants of Santa Monica, California. The CT-1 was an S-100 board, consisting of a formant-based synthesizer, driven by nine parallel output ports. The data rate required was only 100 bytes per control parameter per second, or 800 bytes per second for normal speech.

Several software packages were provided: the CTMON program and later CTEDIT, allowing the user to enter and edit parameter data. Another package called CSRl, the Computalker Synthesis by Rule Program, accepted as input a character string of phonemes from the International Phonetic Alphabet and generated fairly good speech. During the mid-1970s, several other singleboard speech synthesizers became available, allowing hobbyists and researchers to experiment with state-ofthe-art hardware and software without going into debt.

It was not until early in 1979 that I obtained a Computalker board for experimentation. The project was to design a "Bionic Voice" for my friend Bill Rush, a student at the University of Nebraska who has cerebral palsy. (See my article, "A Voice for Bill," in the Winter 1979 issue of onComputing.) I used the CSRl package and wrote a dictionary handler program to make the system easy to use (since Bill does not have full control of his limbs, he types hunt-and-peck style using a stick attached to a band around his forehead).

More recently, I attended a VOCA (Voice Output Communication Aid) Conference in Berkeley, California, in May 1980. It is obvious from such conferences and discussions that voice output for the nonvocal and nonverbal (and talking terminals for the blind) are high on the list of potential applications of voice input/output technology.

On the consumer electronics front, VIO (voice input/output) technology seems to be the trend setter of the eighties. This becomes immediately apparent when one walks through a consumer electronics show, the West Coast Computer Faire, or numerous other product shows. Instead of just flashing lights and color video displays, products are now talking at, about, and with you.

Some recent developments in speech synthesis include the Votrax SC01 single-chip formant synthesizer mentioned in "Articulate Automata" in this issue. Texas Instruments has been at the forefront of the LPC (linear predictive coding) approach. One of its most successful products, Speak & Spell, shows what can be done in the consumer products market.

Articles Policy

BYTE is continually seeking quality manuscripts written by individuals who are applying personal computer systems, designing such systems, or who have knowledge which will prove useful to our readers. For a more formal description of procedures and requirements, potential authors should send a large |9 by 12 inch, 30.5 by 22.8 cm), self-addressed envelope, with 28 cents US postage affixed, to BYTE Author's Guide, POB 372, Hancock NH 03449.

Articles which are accepted are purchased with a rate of up to S50 per magazine page, based on technical quality and suitability for BYTE's readership. Each month, the authors of the two leading articles in the reader poll (BYTE's Ongoing Monitor Box or "BOMB") are presented with bonus checks of SI00 and S50. Unsolicited materials should be accompanied by full name and address, as well as return postage.

PASCAL/Z - Q.E.D.

Ithaca Intersystems PASCAL/Z is the most powerful CP/M™ compatible Z-80™ Pascal compiler ever . . . and here's why:

PASCAL/Z generates true Z-80 native code — ROMable and re-entrant — 5-1 OX faster than P-code interpreters; permits separate compilation; supports Direct File Access and variable length STRINGs; utilizes fast one-pass recursive descent organization; the macro-assembler generates relocatable object modules; and much, much more.

Complete package includes compiler, macro-assembler, linker/loader and source for the full library on one disk; with free copy of Jensen/Wirth book and complete documentation. Only $395.00.

IT'S DEMONSTRABLE! Don't just take our word for it. Ask for a demonstration of these features and more today at Computerland® and other full-service computer stores.

Ithaca Intersystems Inc., 1650 Hanshaw Road

P.O. Box 91, Ithaca, N.Y. 14850. Phone (607) 257-0190

Computerland is a registered trademark ol Computerland Corporation.

CP/M and Z-80 are trademarks of Digital Research Corp. and Zilog. Inc. respectively.

PASCAL/Z and InterSystems are trademarks of Ithaca Intersystems Inc.

8 February 1981 © BYTE Publications Inc

Circle 5 on inquiry card.

Ithaca Intersystems Inc

Micros for bigger ideas.

TM

The InterSystems

price-performance-reliability story

now has three versions

While everyone's been busy trying to convince you that large buses housed in strong metal boxes will guarantee versatility and ward off obsolescence, we've been busy with something better. Solving the real problem with the first line of computer products built from the ground up to conform to the new IEEE S-100 Bus Standard. Offering you extra versatility in 8-bit applications today. And a full 16 bits tomorrow.

We call our new line Series II. And even if you don't need the full 24-bit address for up to 16 megabytes (!) of memory right now, they're something to think about. Because of all the performance, flexibility and economy

they offer. Whether you're looking at one of our three mainframes, at a new mainframe, expanding your present one or upgrading your system with an eye to the future. (Series II boards are compatible with most existing S-100 systems and all IEEE S-100 Standard cards as other manufacturers get around to building them.)

Consider some of the features: Reliable operation to 4MHz and beyond. Full compatibility with 8- and 16-bit CPUs, peripherals and other devices. Eight levels of prioritized interrupts. Up to 16 individually-addressable DMA devices, with IEEE Standard overlapped operation. User-selectable functions addressed by DIPswitch or jumpers, eliminating soldering. And that's just for openers.

The best part is that all this heady stuff is available now\ In our advanced processor —a full IEEE Bus Master featuring Memory Map addressing to a full megabyte. Our fast, flexible 16K Static RAM and 64K Dynamic RAM boards. An incredibly versatile and

economical 2-serial, 4-parallel Multiple I/O board. Our 6-serial I/O board. Our Double-Density High-Speed Disk Controller. And what is undoubtedly the most flexible front panel in the business. Everything you need for a complete IEEE S-100 system. Available separately, or all together in your choice of DPS-1 mainframe styles.

Whatever your needs, why dump your money into obsolete products labelled "IEEE timing compatible" or other words people use to make up for a lack of product. See the future now, at your Intersystems dealer or call/ write for our new catalog. We'll tell you all about Series II and the new IEEE S-100 Bus we helped pioneer. Because it doesn't make sense to buy yesterday's products when tomorrow's are already here.

Ithaca Intersystems Inc.,

1650 Hanshaw Road/P.O. Box 91,

Ithaca, NY 14850

607-257-0190/TWX: 510 255 4346

DDDte0%vSteDDDS'

K^ Ithaca Intersystems Inc

Micros for bigger ideas.

'&

/

Circle 6 on inquiry card

High Technology

We make our

competition

obsolete

with Information Master.™

Information Master™ is the sophisticate of software packages, but it also speaks your language. Its uncomplicated Englishspeaking design makes it easy to learn. No programming knowledge is necessary. Put it in your Apple II*, and you're ready to go.

High Technology's Information Master organizes and prints everything from mailing lists to stock market data. Specify what records to store, type in the information, and Information Master organizes, calculates, stores and reports. Design your own reports and labels. Information Master is revolutionary in its adaptability and comes with a simple step-by-step instruction manual. Its screen layouts are designed to show you maximum information for easy operation. Information Master is so smart it stops mistakes that our competition lets you make.

If your computer dealer doesn't have Information Master, see one who does.

High Technology's perfect complement to Information Master, Data Master,™allows you to change your mind months later

without redoing all the work you've already

High Technology, Inc.

Software Products Division P.O. Box B-14665 8001 N. Classen Blvd. Oklahoma City, Okla. 73113 405 840-9900

•Apple II is a trade name of Apple Computer. Inc.

Editorial

As VIO technology has become more readily available, there is a natural tendency to make everything from washing machines to automobiles talk back. Although the concept is a novel one, I have enough noise pollution to contend with without adding anonymous electronic voices. The real problem with voice output is that it is omnidirectional. If you're surrounded with devices that spontaneously vocalize, it's not always easy to determine where the voice came from. Picture the executive who has three or four telephones on his desk all ringing simultaneously, all sounding the same. Just as high-density video displays can cause sensory overload, multiplevoice-output devices can also overload the aural channel to the brain.

Voice recognition has taken longer to develop because of the many differences between speakers and the different shades of nuance inherent in contextual information. Factors such as the emotional content of the speaker's voice, the accent or dialect, and (the biggest problem) continuous recognition, have slowed the evolution of voice input technology. Continuous recognition means that the computer must be able to determine the beginning of one word and the ending of the last — not a trivial project. For example, the machine may have to distinguish between "I speak" and "ice peak." The problem is further compounded by regional accents and other variables. While great strides have been made in this area, it will probably be many years before generalized continuous voice recognition systems become available. Isolated word recognition is a much simpler problem, and systems are now available with better than 90 percent accuracy when working with a limited vocabulary.

With any new or evolving technology, the challenge is to use it effectively, efficiently, and with imagination. Voice input/output promises to open a whole new dimension to the man-machine interface, one that can be sensed without needing to be seen.

At the end of my onComputing article, "A Voice for Bill," I wrote, "I cannot even begin to imagine what uses Bill will find for his new voice. But if past accomplishments are any indication of things to come, I want to be around in five or ten years to see the results of the seeds we have planted." A year and a half later, my sentiments haven't changed a bit.

Mgj [ReApV] f int I

MPU-COMPATIBLE

SPEECH SYNTHESIS

PROCESSOR

SERIAL. CODED PARAMETER DATA

Photo 2: The TMS5200 LPC (linear predictive coding) speechsynthesizer chip from Texas Instruments.

10 February 1981 © BYTE Publications Inc

Circle 7 on inquiry card.

Circle 8 on inquiry card.

Make the Apple II* a powerful IEEE-488 Controller in a snap.

Just plug the SSM A488 board into any Apple II* expansion slot for a low-cost,

full-featured instrumentation interface. SSM gives the Apple II the power and versatility of a $9,000 IEEE-488 controller. At a fraction of the price. Our board converts the Apple II into a truly sophisticated controller that programs and controls up to 15 different instruments connected together on the 488 bus.

We make programming easy. The 68488 chip, designed by Motorola, forms the heart of our A488. We back this chip with powerful on-board firmware to give you system control via simple string commands. The only software you need is easy-to-program Applesoft* Basic. To develop special purpose firmware, simply replace our PROM with a RAM. With the A488, bus communications operate at top speed—without depending on software loops for timing. And like the more expensive IEEE-488 controllers, this system interfaces with more than 1200 instruments and peripherals.

Suitable for OEMs as well as end users. Whether you make test/measurement systems for resale, or simply for yourself, the SSM/Apple combo gives you top performance. As it cuts your costs. Call your local dealer or SSM today for complete details.

IEEE-488 bus cable

Industrial grade circuit board

PROM firmware for powerful user interface 68488 IEEE-488 controller chip

Slot-independent connection to Apple L

SSM'sA488 board expands the Apple II to a high-performance IEEE-488 controller.

' Registered trademarks of Apple Computer Inc.

SSM Microcomputer Products, Inc.

2190 Paragon Drive San Jose, CA 95131 (408)946-7400 Telex: 171171 TWX: 910-338-2077

High Technology

Have you heard? The Cashier* has been promoted to The Store Manager.

The Cashier has so much more to offer than its name implies that we decided to give it a new name. This valuable software package can save time and increase profits for small business owners by providing:

• real-time inventory control

• point-of-sale functions

• customer & vendor address lists and mailing labels

■ informative management reports

• up-to-the-minute sales monitoring

• invoices, quotations, & packing slips

• purchase orders & receiving reports

• daily, monthly, and year-to-date sales totals

■ physical inventory checklists

• and much, much more.

But what can you call a software package for the Apple II* that does so much? You might call it 'remarkable'... we call it The Store Manager.

Drop by your local computer store and see what The Store Manager can do for you.

Editorial.

High Technology, Inc.

P.O. Box B-14665 8001 N. Classen Blvd Oklahoma City, Oklahoma 73113 405 840-9900

* Apple II and The Cashier are trade names of Apple Computer Inc

/ visited Texas Instruments in early November and was given a demonstration of their text-to-speech technology. The text-to-speech system uses a TMS5200 LPC (linear predictive coding) speech-synthesizer chip similar to that used in the Speak & Spell product line (see photo 2). A message may be entered in standard English, represented in ASCII. The text is then converted to allophone codes (allophones are subsets of a phoneme, the basic unit of speech) which are in turn used to retrieve LPC parameters from an allophone library stored in ROM (read-only memory). Several algorithms are used to smooth the resulting parameters and adjust the amplitude and intonation to yield continuous-sounding speech. The system has inherent advantages; the allophone tables are quite small, typically 3 K bytes for 128 allophones. Other languages may be implemented by changing the textto-allophone rules. I experimented with a version of text-to-speech that ran on a TI99/4 personal computer development system. It accurately interpreted the silent "e" on the end of words like "while" and "release" but misinterpreted the (nonsilent) "e" on the end of my last name, which is not surprising. When given the word "synthesizer" is said "syntheniner."

TI is also working on a timesharing system that is similar to The Source. It will interface with the TI 99/4 and use its graphics, sound, and voice outputs. The system is completely menu driven, and will even log on for you. It sends blocks of information to the TI 99/4, each with a label indicating what kind of data is coming. In this way text, graphics, speech, and music may be sent independently. If the user's system doesn't have certain features, it simply ignores the blocks of data it can't handle. If you ask for the weather reports, it draws a picture on the screen of a sun, rain clouds, or something in between, plays an appropriate tune (ie, "Rainy Days and Mondays"), displays text giving the temperature and other vital information, and can also recite the temperature using text-to-speech. It will be interesting to see how the system is received on the consumer market....MCD

New Computer Speech Developments

Scott Instruments of Denton, Texas, recently announced the VET/2 — a speech-recognition interface for the Apple II. It will run with any existing software because, once loaded, either keyboard or voice input may be used. The program will handle forty-word vocabularies, with the option of overlaying other vocabularies to double or triple the number of words.

Street Electronics of Anaheim, California, has announced the Echo series of speech synthesizers. Versions are being designed for the Apple II and the TRS-80. The units use the Texas Instruments TMS5200 LPC synthesizer chip mentioned in the editorial. The software driver runs in about 900 bytes of memory. Individual vocabulary words take between 10 and 20 bytes, depending on the length of the word MCD ■

12 February 1981 © BYTE Publications Inc

Circle 9 on inquiry card.

Circle 10 on inquiry card.

Edison had over 1,800 patents in ___ his name, but you can be just as inventive

with an Apple.

Apple is the company with the brightest ideas in hardware and software and the best support — so you can be as creative with a personal computer system as Edison was with the incandescent bulb.

How Apple grows with you.

With Apple's reliable product family, the possibilities of creating your own system are endless. Have expansion capabilities of 4 or 8 accessory slots with your choice of system.

Expand memory to 64K bytes or 128K bytes. Add an A to D conversion board. Plug into time sharing, news and electronic mail services. Use an IEEE 488 bus to monitor lab instruments. Add 4 or 6 disk drives — the 5'A" 143K bytes, high-speed, low-cost drive that's the most popular on the market.

Apple speaks many languages.

Since more than 100 companies create software for Apple, you'll have the most extensive library in the personal

computer world. Want to write your own programs? Apple is fluent in BASIC, Pascal, FORTRAN, PILOT and 6502 assembly language.

There's even a series of utility programs called the DOS Tool Kit that not only lets you design high-resolution graphic displays, but lets you work wonders with creative animation.

More illuminating experiences in store.

You won't want to miss all the Apple products being introduced at your computer store all the time. Don't let history pass you by. Visit your nearest Apple dealer or call 800-538-9696. In California, 800-662-9238. Or write: Apple Computer, 10260 Bandley Drive, Cupertino, CA 95014.

apple computer inc.

The Minifloppy tradition. The standard is set for highperformance 96 TPI Minifloppys. And it's by Shugart. Double track and double density, the single and double-sided SA410 and SA460 Minifloppys deliver .5 or 1 MBytes of unformatted capacity on a 5V4-inch diskette. Small wonder. Designed by the company that . invented the Minifloppy, the SA410 and SA460 represent the culmination of all previous 51/4inch disk drive technologies. What you get today is the most thoroughly engineered, most manufacturable, and most reliable Minifloppy drive available. The SA410/460are the new standard in the eighties for price, performance, and capacity.

hugart introduces of Minifloppys:

jStep into the future. Innovation, experience, and proven performance have always been the hallmark of the Minifloppy tradition. And the SA410/460 are the {first of the next generation in that tradition. Utilizing A technology proven in our 8-inch disk drive products, ■ the SA410 and SA460 use a multi-step positioning technique, thus eliminating pole asymmetry, an inherent source of positioning errors and degraded performance. The simplicity of this multi-step positioning motor and the HeliCam lead screw follower insure its manufacturability, consistent high performance, reliability, and low cost.

'"Trademark of Shugart Associates

Positioned for success. Shugart's new HeliCam™

positioner delivers far greater accuracy than that of

competitive actuators. The result is super precise

positioning tolerances that virtually eliminate the

problems of media interchange previously associated

with 96 TPI 51/4-inch technology. The HeliCam

solution means that you can reduce, by a significant

margin, data handling errors—especially between

systems in less than ideal environments.

the next generation SA410/460.

A new era starts today. Our commitment to the 51/»-inch disk drive market is driven by your requirements for low cost, highly reliable disk drive solutions. With unmatched commitments in manufacturing and R&D resources, we're dedicated to delivering innovative, standard-setting products that meetyour needs—both today and tomorrow. And we back all our products with superior technical support, design assistance, and in-depth documentation. Call today. We'll be delivering in production volumes by early 1981. D Shugart Associates: 475 Oakmead Parkway, Sunnyvale, CA (408) 733-0100. Sales & Service:' Sunnyvale, CA; Costa Mesa, CA; Minneapolis, MN; Richardson, TX; Framingham, MA; Mt. Freedom, NJ; Atlanta, GA; Toronto.Ontario; Paris, France; Munich, Germany. D

^.Shugart

The next generation is here

Circle 11 on inquiry card.

Letters

Katchlng Up with Khachlyan

I would like to commend the authors of "Khachiyan's Algorithm" (G C Berresford, A M Rockett, and ] C Stevenson) published in the August and September 1980 BYTEs (pages 198 and 242, respectively). Their presentation illustrated the essentials of the algorithm without getting bogged down in its derivation. However, now that I understand it (I hope), it is somewhat disillusioning to realize that the "amazing shortcut" appears to be only a nonpractical mathematical curiosity.

I have some observations regarding the algorithm. First, the huge initial volume subsequently requires the incredible precision. Hadamard's initial volume is much smaller, and this should reduce the precision requirements; but by how much? Also, if upper bounds are defined for all X„ would this be helpful7

Even if the precision problems are solved, the total number of arithmetic operations to solve a large linear-programming problem still appears to be intractable. The upper bound for the number of iterations is lbLn , and each

iteration uses Order(« + m) multiplications for the matrix inner products. Presumably, if a solution exists, the number of iterations will be much less than ltLn (but by how much?), and the number of multiplications per iteration can be reduced to Order(n + m) via Strassen's algorithm. However, both of these appear to be greater than those required by the usual revised Simplex algorithm. While the Simplex algorithm can require Order(2") iterations, it usually finds the optimal solution in Order(m). Also, each iteration needs only Order(mn) multiplications (revised Simplex).

Memory requirements also seem to put Khachiyan's algorithm at a disadvantage. The giant A array (see statement 430, listing 1, September 1980 BYTE, page 246) can be reduced to negligible size using linked lists, and the Ql and W arrays could use the same space, but this still leaves three (m + ri) by [m + n) arrays for Khachiyan's algorithm. In contrast, the only large array for the revised Simplex is the m by m B array.

The problem of solving large linearprogramming problems looks more

^DISK DRIVE BONANZA BY QT^

8" DISK DRIVES Shugart 801R Sgl/side Dbl/Den $395.00 Two for $775.00

Qume Datatrak 8'dbl sided, dbl density.

QME-8DS (851 R compatible) $ 599.00

Pkg of two $549.00 ea

QT DISK PACKAGES

I Dbl Den Controller, A & T, two 8" dbl den drives. CP/M®

2.2, cabinet, power supply & cables $1395.00

H Two 801R disk drives with cabinet, power supply & fan $1100.00

III Dual 8" Drives:

Dbl den drives in cabinet only

2 sgl sided (801R) $ 989.00

2 dbl sided (QUME) $1409.00

51/4" DRIVES

MPI-B51 MPI B-51 S250.00

Sgl Sided Sgl/Dbl Den

Exact Replacement for SA-400 MPI-B52 MPI B-52 S350.00

Dbl Sided. Dbl Den

9t

*z

COMPUTER SYSTEMS INC. 15620 South Inglewood Ave. Lawndale, California 90260 (213) 970-0952

c

J

MPI-B91 MPI B-91 S375.00

Sgl Sided. Dbl Den, 77 Tracks PERTEC FD-200 PER-FD200 S225.00

Sgl Sided. Sgl/Dbl Den Shugart SA400 SHU-SA400 S250.00

Sgl Sided. Dbl/Den

WE ACCEPT M/C, VISA, AM EXP PLACE ORDERS TOLL FREE

1-800-421-5150

(CONTINENTAL U.S. ONLY)

(EXCEPT CALIFORNIA)

CP/M is a trademark ol Digital Research

promising if array-oriented hardware is used. For example, a clocked matrix multiplier can read in, compute, and write out the inner product of two n by n matrices in 5 n clock periods. This would be an immediate benefit for the revised Simplex as well as a help to Khachiyan's algorithm, if the precision problem can be overcome.

William J Butler Jr 44 Dees Cr Warwick RI 02889

Berresford, Rockett, and Stevenson Reply

We are happy that you found our articles on Khachiyan's algorithm so informative. Our purpose was to encourage such experimentation with the algorithm. As the articles explained (and, incidentally, earlier than any other journal as logged in the February 1980 issue of Abstracts of Papers Presented to the American Mathematical Society,), Khachiyan's algorithm is not capable of immediate practical application largely because of the incredible precision required.

In fairness to Leonid Khachiyan, it is clear from his paper that he never intended his result as a practical method for solving linear-programming problems. In fact, linear programming is only mentioned in one sentence in the introduction, the rest of the paper being devoted to the consistency problem for linear inequalities. His purpose was a purely theoretical one: to prove that linear consistency and, therefore, linearprogramming problems could be solved in polynomial instead of exponential time. It was the American and European press (with the exception of BYTE) that erroneously construed the result as one of practical rather than theoretical importance. (In fact, many other journals have had to issue retractions or corrections of earlier ill-considered statements.)

As to your specific questions, there is little we can say except to answer "yes": your suggestions would doubtlessly improve the algorithm. Dr Philip Wolfe of IBM (Yorktown Heights, New York) has been serving as a clearinghouse and evaluator for the numerous improvements to the algorithm that have been suggested, but none so far seem to accelerate the algorithm by as much as one order of magnitude. Thus, it is far from competitive with the revised Simplex algorithm. While the Klee-Minty example shows that the Simplex method is an exponential-time algorithm, problems similar to Klee-Minty rarely occur in practice, and when they do, standard

16 February 1981 © BYTE Publications lnc

Circle 12 on inquiry card.

Circle 13 on inquiry card.

Now with n

for thousands motffirogramsT^and new 8-inch disk systenrfor millions more bytes.

1

[^■^1

T~l

t

*iI^M

i

; i

J

1 sw^

•

The Heathkit All-in-One Computer now has space for 64K of addressable RAM, so you can run bigger, more complex programs.

And our new CP/M'" Operating System (Standard ORG-0, Version 2.2) makes thousands of CP/M programs available to you. Heathkit systems can run more, do more, store more than ever before. A new 8-inch double-sided, double-density disk system, with over 1 million bytes per drive, is now available for Heathkit H-89 and H-8 Computers. The new 8-inch disk system features soft-sectored disks for IBM"* compatibility. It's capable of operating in standard IBM 3740 format. And the 8-inch sys

VISIT YOUR HEATHKIT STORE

Heathkit products are displayed, — sold and serviced at Heathkit Electronic Centers*, located in major cities throughout the U.S. and Canada. See your white pages for the store nearest you.

'Units of Veritechnology Electronics Corporation, in the U.S.

?Wa

tern can be used in conjunction with 5%-inch systems. For compatibility with the rest of the industry, Heathkit Computers may just be the most flexible systems you can buy.

All Heathkit computers and peripherals are available in money-saving, easy-to-build kit form —or completely assembled and factory tested. All are supported by the best documentation in the business and by 62 service centers throughout the U.S. and Canada. You're never out in the cold. For complete details and prices on Heathkit computers, peripherals and software, write today for the latest Heathkit Catalog or visit your ililfjf I nearby Heathkit Electronic Center*.

",*A * Send for FREE catalog

Write to Heath Company, Dept. 334-744, Benton Harbor, Ml 49022

I In Canada, contact Heath Co., 1480 Dundas St. E., Mississauga, Ontario L4X 2R7

Heathkit

IBM is a registered trademark of International Business Machines Corporation. CP/M is a trademark of Digital Research, Inc.

Letters.

tricks (such as reseating) usually greatly reduce the time needed for solution. In fact, experience seems to indicate that the revised Simplex method is almost linear in the number of variables, thus making it hard to beat.

A more complete answer to your questions about improving Khachiyan's algorithm will have to await large-scale experimentation by IBM and others.

Comments on the Heath H-89

In regard to Mark Dahmke's review of the H-89 (see "The Heath H-89 Com

puter," August 1980 BYTE, page 46), I agree with him until he starts talking about the "disadvantages." The text editor is not that hard to operate, and, if he thinks it is, he can get a different one from HUG (Heath User's Group) or other sources in Buss. He also mentions the lack of a RUN "FNAME" command in BH (Benton Harbor) BASIC, but, in version 1.6, which is the version Mr Dahmke worked with, you can say CHAIN "FNAME" with the same results.

All of Mr Dahmke's other observations are true, but there are cures. For example, to keep the disk head from banging up and down, change the HS

YOU THINK YOU'VE SEEN WORD PROCESSING SOFTWARE?

The

MAGIC WAND

Word Processing

System offers you the best features of any system in the micro market

FEATURES INCLUDE:

Full-screen text editor

Simple, control key operation Edit programs as well as text

Assemble, compile or run programs

without modification Files larger than memory

Files up to 256K Library files

Merge part or all of one file with

another Spool printing

Print a file while editing another Easy page formatting

Simple commands set margins, page

length, etc. Override commands at run-time

Give any command from the keyboard as well as in file Variablepitch control

Change pitch in mid-line, even

mid-word Up to 128 user-defined variables

String, numeric or dollar format Form letter generation from external data files

Compatible with both sequential and

fixed-record files Conditional commands

Any command may be conditional Print to disk and/or printer

Save all or part of output on disk Switch from specialty printer to CP/M list device

Print the same file on either specialty

or standard printer

Version 1.1 is now available

EASE OF OPERATION

With all its power, the MAGIC WAND is remarkably easy to use. This is no accident. The command structure is designed to be flexible and logical so that you can perform basic functions with a minimum of commands.

We have included in the manual a stepby-step instructional program, for the person who has never used a word-processor before. The trainee uses sample files from the system disk and compares his work to simulated screens and printouts.

In addition to the lessons, the manual has a complete documentation of the command structure, special notes for programmers, an introduction to CP/M for non-programmers and a glossary. The manual is typeset, rather than typewritten, for greater legibility.

We have written the manual in nontechnical English, because wewantyou to read it. We don't overload you with a bunch of jargon that could confuse even a PhD in Computer Sciences.

We send out newsletters so that users of the MAGIC WAND can learn special applications of the print commands. For example, we might show you how to create a mailing list or set up an index for a file.

In short, we've done everything we can to make things easy foryou. Because the best software in the world is just a bunch of code if you can't use it.

For more information, call or write:

sttiaYY business o^vcaXvous, uic.

3220 Louisiana • Suite 205 • Houston, Texas 77006 • 713-528-5158

CP/M is a registered ii

k ol Digilai Research Coip

jumper to open and the HM jumper to closed in the disk unit on the "programming plus." Then the head stays loaded as long as the motor stays on, about a minute after the last operation. Of course, you could time-delay the load signal.

The last, and probably more important, point is how not to need the HDOS system on every disk. On version 1.6, the command SET HDOS STAND-ALONE can be used and, after the warning message, the command RESET SY0: will be honored. This might mess up versions earlier than 1.6; and, if you land on a disk while not in PIP or ONECOPY, the SYSCMD.SYS will load. If the verions differ, you might get a FATAL SYSTEM ERROR, but, all in all, it is a good trade-off. Be sure to LOAD LP: and other DUDs before RESETing after BOOT up.

Bill Pinkston Saltillo MS 38866

If I may add a few things to Mr Dahmke's review of the Heath H-89: Heath's BH BASIC is neither fast nor high in precision (my Ohio Scientific C3 will run circles around it), but it does have one great advantage for the debugging phase of programming. While other BASICs will null all variable and array values upon a revision of any line of program, however trivial, BH BASIC does not. Thus you can stop execution, fix up a defective line, and restart in mid-program, rather than having to rerun from the beginning—a real advantage for long programs, and for programs requiring many INPUTs to get going.

A detail I like about the H-89 is its ability to take commands in lowercase, converting input to uppercase as needed. That's very nice if you spend a lot of time in the word-processing mode.

Oddly, Mr Dahmke had little to say about the display and keyboard. I have to cope daily with a Televideo 912, an industrial-grade terminal which will cause you to appreciate the superior quality of the H-89 display and keyboard. The 912 is susceptible to false key contacts, which usually cause the display to do truly weird things, thereby forcing you to abandon your input and to refresh the entire display. It also gives no audible confirmation of key contact; and the 80-character line is limited to perhaps two-thirds of the screen width, wasting the rest of the screen. The H-89 terminal runs at 9600 bps (bits per second)—some have been pushed to 19,200 bps—a difference especially noticeable in word-processing and financial programs, for which execution time is limited by the display, rather than by computation.

18 February 19S1 © BYTE Publications Inc

Circle 14 on inquiry card.

MM

Mountain Computer

can now

EXPAND

Your Apple II Peripheral Capacity

EXPANSION CHASSIS

duality You Expect

Eight more slots for your Apple! Now you can bank-select eight more peripheral slots with immediate or deferred software commands—like having up to 16 peripheral cards "on line"—or use the Select/Deselect switch mounted on the front panel. Expansion Chassis' heavy-duty power supply is primarily for peripherals, without the heavy demand of motherboard support chips required in your Apple. This means much more power is available for peripherals than in your Apple itself! If you've run out of room in your Apple—Expansion Chassis is your answer. Drop by your Apple dealer for a demonstration, or contact Mountain Computer for the location of the dealer nearest you.

Performance You Demand

• Eight mirror image I/O slots of the Apple

• Fully buffered, bi-directional data lines

• Apple II compatible interface card

• Dual selection capability; hardware or software

• Immediate or deferred selection in software mode

• From BASIC, a single POKE command turns the chassis ON or OFF

• Compatible with all software

• Dedicated power supply with approved power transformer

K Mountain Computer

INCOBPORATED*

300 Harvey West Blvd., Santa Cruz, CA 95060 (408) 429-8600 TWX 910 598-4504

Apple is a trademark ol Apple Computer Inc.

Circle 15 on inquiry card.

BYTE February 1981 19

Letters.

I have to disagree with Mr Dahmke's assertion that the Heath text editor is useless. I use it, as a word processor, for hours every day, with no difficulty; however, I'm not hampered by familiarity with any other text editors. Mr Dahmke's statement that the H-89's reading of error messages from disk takes "several seconds" is, frankly, an exaggeration. The actual elapsed time is under one second, though it certainly seems longer. Also, the disk head does not touch down for "each and every sector"; it reads the sectors in pairs, touching down for every other sector, which is noisy and slow enough.

If you want a sophisticated machine, or a fast, high-precision computer, the H-89 isn't it. The H-89 is a fine wordprocessing and financial computer, right for the user who doesn't want to get deeply involved in computer hardware and software.

Jack McKay

3200 19th St NW Washington DC 20010

Mark Dahmke Replies

/ thank Mr Pinkston and Mr McKay for their comments about my review, and for bringing the various "fixes" to my attention and to that of BYTE's readers. My philosophy for reviewing equipment is that 1 am reviewing essentially what comes out of the box. Any updates from readers are greatly appreciated, but I feel I must give potential buyers an accurate indication of what the product is like as it comes from the manufacturer. As for the other comments regarding the editor, I will stand by my statements in the review.

Dissecting the Speak & Spell Article

The article published in the September 1980 BYTE concerning the TI (Texas Instruments) Speak & Spell (see "Dissecting the TI Speak & Spell," by Michael A Rigsby, page 76) contains a number of serious errors that must have upset staff scientists Richard Wiggins and Larry Brantingham at TI's Central Research Laboratory in Dallas, Texas.

To suppose that the TMC0281 device used in the Speak & Spell is the same as the SN76477 is to greatly underestimate Texas Instruments' achievement. The TMC0281 is, in fact, a complete speechsynthesizer device fabricated in metalgate depletion-load p-channel technology and contains an entire digital-signal processor, with timing and decoding circuits, a ten-stage digital lattice filter, and a D/A (digital-to-analog) converter. The system is based upon the relatively new

20 February 1981 © BYTE Publications lnc

voice-compression technique known as linear predictive coding. This technique can generate high-quality speech from low data rates (less than 2400 bits per second). Linear predictive coding is so called because of the way in which the coefficients that characterize the digital filter are predicted from a linear combination of the previous coefficients. This requires a great deal of number crunching—in the case of the TMC0281, 160,000 additions and 160,000 10- by 14-bit multiplications every second. TI confounded the many skeptics who said it couldn't be done. To get around the speed problem, Wiggins transformed all the calculations into a fixed-point format and Brantingham designed a pipeline processor that is contained within the TMC0281.

The coded speech data for the synthesizer device is stored in the TMC0351's read-only memory. These are 16,384 by 8-bit devices (ie: 128 K bits) having an internal 18-bit address counter/register and two 8-bit output buffers. Fourteen of the address bits go to the memory array directly, while the 4 most significant bits are used in a l-of-16 chip select.

The controller chip, the TMC0271, is a slightly modified calculator chip, a member of the Texas Instruments TMS1000 family. It has been modified to enhance its BCD (binary-coded decimal) arithmetic and expand its instruction set. Also, there is an output multiplexer to reduce the pinouts needed for the Speak & Spell application.

Contrary to the implications in the article that the "operation of the Speak & spell involves many unknowns," TI has, in fact, published full details of its threechip synthesizer system (see Electronics, August 31, 1978, pages 109 thru 116) and many other articles have appeared. A letter to TI brings (at least in my case) a set of reprints.

Tim Spracklen

23 Buttermere, Greenways, Spennymoor

Durham, DL16 6UD, England

De Facto of De Matter

This is a plea for order in what could be the next standards chaos: Sol Libes mentioned a Massachusetts company planning to use home VTRs (videotape recorders) for hard-disk backup. (See "Backing Up Winchesters" in "BYTELINES" October 1980 BYTE, pages 188 and 189.) Corvus also plans such a system. Our company, D C Crane lnc, is planning one using the Digital Graphic Systems CAT-100 videodisplay board.

The technique will allow saving and

Circle 16 on inquiry card.

A growing line of tools to expand the Apple.

7440A Programmable Interrupt Timer Module.

Time events in four operating modes—continuous, single shot, frequency comparison, and pulse width comparison. Includes three 16-bit interval timers, plus flexible patch area for external interface. Programmable interrupts, on-board ROM, and much more.

7720A Parallel Interface. Two bi-directional 8-bit I/O ports will connect your Apple to a variety of parallel devices, including printers, paper tape equipment, current relays, external on/off devices. Full featured, programmable interrupts, supports DMA daisy chaining.

7811B Arithmetic Processor. Interfaces with Applesoft, so you just plug in and run. Based on the AM 9511 device, provides full 16/32-bit arithmetic, floating point, trigonometric, logarithmic, exponential functions. Programmed I/O data transfer, much, much more.

7710A Asynchronous Serial Interface. Conforming to RS-232-C A thru E 1978 standard, this card will drive a variety of serial devices such as CRT terminals, printers, paper tape devices, or communicate with any standard RS-232 device, including other computers. Full hand-shaking, and fully compatible with Apple PASCAL!

7470A 3tJ BCD Ay D Converter. Converts a DC voltage to a BCD number for computerized monitoring and analysis. Typical inputs include DC inputs from temperature or pressure transducers. Single channel A/D, 400 ms per conversion.

7490A GPIB IEEE 488 Interface. A true implementation of the IEEE 488 standard—the standard protocol for instrumentation and test devices. Control and monitor test instruments such as digital voltmeters, plotters, function generators, or any other device using the IEEE 488.

7114A PROM Module. Permits the addition to or replacement of Apple II firmware without removing the Apple II ROMs. Available with on-board enable/disable toggle switch.

7500 A Wire Wrap Board. For prototyping your own designs.

7510A Solder Board.

7590A Extender Board.

Watch this space for new CCS products for the Apple. We've got some real surprises in the works. To find out more about the CCS product line, visit your local computer retailer. The CCS product line is available at over 250 locations nationally, including most that carry the Apple. Or circle the reader service number on this ad.

Apple II, Apple II Plus, and Applesoftaretrademarks of the Apple Corporation.

CCS makes the difference.

We see the Apple

We see it as a good way to get things done.

Apple has built a great computer. We at CCS have built a great line of peripherals and components to expand the Apple. To do almost anything you want to get done with a computer.

If you wafit to do business with an Apple, we've got tools to connect the Apple to standard business printers and terminals. Or to modems, for communications over telephone lines, with other computers, even with other Apples.

If you want to apply your Apple to engineering, scientific, or graphic projects, we've got tools for high-powered,

mwm\

high-speed math functions, and fast, high resolution graphics. And tools to connect the Apple to lab test equipment like function generators or plotters.

And we have tools to connect the Apple to the outside world, including A/D converters and interval timers with external interface.

We make components for the S-100 bus, the PET, and the TRS-80, too.We built our products to deliver hardnosed value to the OEM, and to the inventor who knows the best, at prices that are unbeaten.

To find out how much computer your Apple II can be, see things our way. Because for serious users with serious uses for the Apple, we've got the tools.

California Computer Systems

250 Caribbean Sunnyvale, CA 94086 [408] 734-5811

APPLE n OR APPLE II PLUS

Shipped direct to you!

s89900

(Plus Shipping)

We have orchard fresh Apple products ready to ship. Immediate delivery with cashiers check. Orders with personal checks shipped after bank clearance. COD's require shipping charges be paid in advance.

16K UNITS $899

64K(16Kinslot)

$1250

Apple Disk Drive $550 Pascal Language Card

$450

Above plus $20 shipping charge.

IMPORTANT—No shipments made within the state of Illinois.

THE COMPUTER ROOM

P.O. BOX 11375

CHICAGO, IL 60611

(312)427-1941

ORDER

Enclosed $_ For

FORM

_Via U.P.S.

Ship to: Name_

Address.

(No P.O. Boxes-Street Address Only)

City

State.

.zip

Letters ^—^—^—__

restoring hundreds of megabytes. It will also establish de facto interchange standards. Could we learn from the past7 Just this once7 Please7

I would like to hear from anyone interested in helping develop or use such a standard with a view toward documenting the problem and the solutions in an article for BYTE. If a formal standards commission is interested, so much the better. Please write me at the address below. I will put you in contact with each other and contribute my ideas toward a solution.

David C Crane D C Crane Inc POB 79286 Houston TX 77079

Have You Tried onComputlng?

For fifteen years I have dreamed of using a computer for my one-man business. I have tried to find the right one in BYTE, on and between the lines. The result of my search is the feeling that, to become "computerized," I must become an expert in mathematics (Boolean and otherwise), electronics, hardware, software, semiconductors, integrated circuits, languages, and all the rest of the stuff. Oh, my aching head! Help, help! The computer train is rolling so fast and I am unable to climb aboard.

When I first became "motorized," I didn't have to be an expert in mechanics, thermodynamics, aerodynamics, electricity, tire structure, fuel chemistry, etc. I simply sat in the car and—without any help—taught myself the rules of the road. Who can, for a moderate price, link together and harmonize some of the wonderful programs advertised in BYTE to make a system coherent, practical, and flexible?

R E Gilbert Jozef Hermanslei 41 B-2510 Mortsel Belgium

Of course, a computer is much more complex than any automobile, but the analogy is still valid. People should be able to get what they want from a computer with a minimum of fuss. Until then, Mr Gilbert, guides are necessary: enjoy the complimentary copy of onComputing; she's our sister publication for the layman.

Sharp-Looking TRS-80

Upon studying the advertisements for the new TRS-80 Pocket Computer, I was surprised to find the letter Y's original

22 February 1981 © BYTE Publications Inc

second function (ie: ¥, for the yen on the Sharp PC 1211) deleted.

If that's the way the Tandy Corporation has to lure prospective customers into thinking that the Pocket Computer is Ail-American made, I pity any Japanese importer trying to sell an American computer without String-capability....

Marc H Bruna Abrikozenstraat 31 2564 VK Den Haag Netherlands

Tree Is Root of Problem

As a fellow member of the University of Oklahoma, I feel it necessary to point out some of the areas where I disagree with Dr Bill Walker's article "Sorting With Binary Trees" (October 1980 BYTE, page 96). These areas will be dealt with in the same order as they appear in the article.

First, Dr Walker gives the impression that a tree sort is both fast and allows deletion of nodes in an efficient manner. As he says, a tree sort is faster than a bubble sort, but almost any serious sort routine will be faster than a bubble sort. Likewise, deleting a node from a tree is faster than deleting an element from a bubble-sorted list, but deleting nodes from trees, except in the special cases of AVL; B; and 2-3 trees, is not particularly fast. (See The Design and Analysis of Computer Algorithms, by Alfredo Aho and Jeffrey D Ullman. Reading MA: Addison-Wesley, 1974.)

Second, students of graph theory tend to define a tree as an acyclic graph. (See Graph Theory, by Frank Harary. Reading MA: Addison-Wesley, 1969.) By this definition, the object presented in Dr Walker's figure 1 is not a tree, but a rooted graph.

Third, Dr Walker states that one way of scanning a sorted tree (a binarysearch tree) would be to first visit the leftmost node in each branch, then the parent, and finally visit the rightmost node, repeating this sequence until finished. He proceeds to say that this is "tough for computers." However, the C-language routine in listing 1, page 24, performs Dr Walker's suggested algorithm.

Next, the algorithm used to search a tree can be cleaned up considerably, as shown in listing 2. The algorithms used to delete and add nodes are excellent, and rewriting those in C would serve no other purpose than to expose the deficiencies of Pascal.

We now have nice, short algorithms to do everything that Dr Walker wanted to do to the tree, except to delete nodes

Circle 17 on inquiry card. »

MICROSETTE

C-10—$1.00 C-60—$1.75

Al

DATA TAPE

•

t

50

FEET

MICHOSETTE CO.

475 Ellis St.

Mt. View, CA 94043

• •

• •

[ A'

DATA TAPE

•

■•

100

FEET

1 MICROSETTE CO.

475 Ellis St

, Mt. View, CA 94043

• •

• •

$1.25

MICROSETTES FOR COMPUTERISTS

In the amazing microcomputer industry a three-year-old product is a winning product. Microsette users acclaim the excellent value and reliability of these cassette tapes for safe storage of their computer programs. Microsette 50-foot and 100-foot length cassettes aire backed by a 30-day warranty for use on all popular microcomputers. The two convenient lengths store the complete memory contents of most microcomputers. The tapes are as excellent for Hi-Fi audio as for microcomputer use.

MICROSETTE CO. 475 Ellis

St.

Mt. View, CA 94043

•• «

MICROSETTES FOR AUDIOPHILES

Audiophiles are very selective when it comes to media for their high fidelity systems. A recent survey of BYTE Magazine readers revealed that 98% own high fidelity audio equipment. Microsette tape quality is already well established with microcomputer owners. Now Microsette offers popular C-60 arid C-90 length cassette tapes for the computerist who is also an audiophile.

Dealer prices are 50% of list. Available in 250 quantity case lots only. Write or call (415) 968-1604 for complete details.

Microsette Co., 475 Ellis St., Mountain View, CA 94043

Circle 18 on Inquiry card.

Have some

gieat memories.

16K PROM boards.

■ PROM card has 2708-type memory

■ Quality board construction ■ 0-4 wait states

■ Address any 4K group to any 4K boundary

■ Control up to 8 banks of memory ■ Fully assembled and tested ■ PRICE—$300

(California residents add 6% sales tax)

Expandable 5 MHz RAM boards.

8—32K expandable RAM board uses TI 4044 memory runs at 5MHz ■ Fast 250 ns access time ■ Bank select ■ Address any 4K block to any 4K boundary ■ Quality board construction

PRICE—8K—$175; 16K—$315; 24K—$475; 32K—$620; 8K add-on kits—$135

(California residents add 6% sales tax)

Call or write Artec for details

Letters.

from it. As far as I know, the algorithm he used cannot be improved upon to any great extent. This point is the basis for my statement that it is not relatively easy to delete nodes from a tree.

To achieve the operations Dr Walker wants (easy insertion and deletion, while maintaining a sorted list, plus easy searching), I would recommend a double-linked list. The algorithms for dealing with this structure can be found in any good data structures or algorithms text.

Mike Meyer, Student University of Oklahoma POB 1749 Norman OK 73070

J thoroughly enjoyed Dr Walker's article on binary-tree sorting in the October BYTE. He presented a subject that often receives a boring and confusing treatment in an interesting and clear manner. Since the amount of data I must sort daily has recently doubled, the article came at the right time.

Time after time I have seen the subject of trees presented in magazines and books. Each time I lacked the incentive to actually implement a tree structure on my system. The whole thing seemed too complicated for the results obtained. However, Dr Walker provided the push I needed to get it going.

Although some of the coding is redundant, by the author's own admission, and is slightly inefficient in some areas

(due mostly to the direct conversion from FORTRAN and his desire to keep the program portable), the program makes sense. That sounds simple, but many programs don't make any sense at all—they just work "somehow."

Because of the use of highly structured subroutines and "standard" BASIC, I easily translated the program of his listing 1 into Oasis BASIC and modified it for operation on strings. This later change is simple if the BASIC used dimensions a string-array length rather than a string length. The modification to sort strings requires changing P in lines 200 and 205, KEY, and ALPHA to string variables. It works well and fast.

I did, however, find one major design problem. It is associated with the deletion of a right terminal node that is not the last node in the sorted sequence. Both the coding of line 3090 and the logic of table 1, Case II, Group B, Subcase 1 call for setting the right link pointer of the parent Q to NIL (setting RLINK(Q) = NIL). This tells the treetraversal routine that this parent is the last item in the tree. Often it is not.

The proper logic is to set RLINK(Q) equal to RLINK(P). In this way, the parent Q of the deleted node P will point back to the ancestor node, the one that follows it in the sorted sequence. If the deleted node P was the terminal node of the entire tree, its parent, Q, will assume this property when the node P is deleted. That is the only problem I found.

Listing 1

dKTGC GLGCTROMiajMC

605 Old County Rd., San Carlos, CA 94070 Telephone (415)592-2740

struct node {

i n t info ;

struct node *leftson, *rightson ;

1 ;

visit(root) struct node *root; {

if (root == NULL) return ; visit(root -> leftson) ; printf("%d ", root -> info) ; visit(root -> rightson) ; }

Next, the algorithm used to search a tree can be cleaned up considerably, as shown:

search(root, item) struct node *root; { while (root != NULL) {

Listing 2

if (root -> info == item)

return(root) ; if (root -> info > item)

root = root -> leftson ; else

root = root -> rightson ;

} return(NULL) ; 1

24 February 19S1 © BYTE Publications Inc

Circle 19 on inquiry card.

Two proven ways to expand your TRS-80* capability

Exatron's Stringy/Floppy... speed, capacity and reliability fQLonly $249.50

8C IS

TRS-80 User's Journal

New "How-To" info

for the serious

TRS-80 user

Exatron's Stringy/Floppy mass storage system

gives you the speed, capacity and reliability of a mini-disk

system at far less cost. Thousands of ES/ F users agree.

Here's your complete Starter System:

• ES/F Operating Manual

• Basic ES/F System ($249.50)

• 10 Blank Wafers

• ES/F Monitor Program

• Tutorial Demo Program

• 2 for 1 Bus Connector

Data I/O Program

FREE 1 Year Subscription to 80-CJ.S., the User's Journal

Complete Info Package

Complete Starter Kit: $299.50

80-CI.S. is expanding with more pages, programs

and color with heavy emphasis on advanced

TRS-80 applications...plus a regular Exatron

Stringy/Floppy feature.

Special Introductory offer $9.95 per year

We'll send you six issues of 80-CI.S. for only $9.95... almost half the regular price. If you purchase an Exatron Stringy/Floppy System, we'll send them FREE.

OFFER VALID UNTIL MARCH 31,1981. Send to:

CALL OCIR FREE HOTLINE (800) 538-8559

IN CALIFORNIA: (408) 737-7111

80S

Sign me up! I can't resist at $9.95!

□ Check □ Money Order DM/CorVisa

80-CI.S. Journal 3838 South Wamer Street Tacoma, WA 98409 (206) 475-2219

CARD NUMBER

Or contact:

exatron

181 Commercial Street Sunnyvale, CA 94086

TRS-80 Trademark of Tandy Co.

STATE ZIP

Offer good only In the United States.

Circle 20 on inquiry card.

TOUGHEST BOARDS IN TOWN

FOR S

Monitor and control

in wicked environments.

Want to put your S-100 system to work in the world of computerized monitoring and process control?

Dual Systems has all the boards it takes to do the job in the toughest factory environments. All are designed to function dependably in the real world of industrial control. All operate with Cromemco, North Star and other S-100 systems. A/D board. 12-bit precision. 32 singleended inputs. Or 16 differential inputs. 25 us conversion time. Vectored interrupt. $635. Or $725 with 1 to 1000 gain transducer amplifier. Works with our thermocouple compensation board and our 4-20 mA input boards as well. D/A board. Four independent channels. 12-bit precision. Input is binary or 2's complement. Compatible with all existing I/O mapped software. $495. Drives our amplifier board which outputs 4-20 mA. CMOS RAM board. On-board battery back-up preserves data a year. 200 ns read/write time. Runs at 4 MHz. 8K bytes $590. 16K bytes $990. CMOS clock board. On-board battery back-up keeps clock running a year. New LSI chip carries date, hours, minutes and seconds. Read or write directly from I/O port. Vectored interrupt. $250.

We also provide complete mainframe systems. OEM and dealer inquiries are invited.

Contact Dual Systems Control Corp., Dept. B, 1825 Eastshore Hwy., Berkeley, CA 94710. Phone (415) 549-3854.

Letters,

Many thanks to Dr Walker. It was a great article; I would enjoy seeing more articles from him in the future.

Jack Dolby

335 D-l Hiddenwood Dr

Newport News VA 23606

Screen Print for TRS-80

In the October BYTE, Teri Li's 'Technical Forum" talks about some of Radio Shack's modifications for the TRS-80. (See "Radio Shack's Modifications to the TRS-80," page 182.) The screen-print problem created by the lowercase modification has a simple solution. Run the program shown in listing 1.

The screen will display: @ABCD EFGHIJKLMNOPQRSTUVWXYZ (up arrow) (down arrow) (left arrow) (right arrow) (dash)

This is how TRSDOS prints characters to the display. The alphabet codes are decimal 1 to 26. If we add 64 to each decimal value PEEKed from the display that is less than 32, then print the CHR$ equivalent to the printer, no problem will be encountered.

The program in listing 2, called as a subroutine, will print the contents of the display to a line printer.

This routine works on uppercase and upper/lowercase keyboards.

Gary E Alcorn 1037 E Redondo Dr Tempe AZ 85282

Listing 1 10 CLS

20 FOR A = 15360 TO 15391 3 0 POKE A,B 40 B = B + 1 5 0 NEXT A 60 PRINT 70 END Listing 2

50 0 0 P = 1536()

5010 FOR V = 1 TO 15 : FOR H = 0 TO 63 5020 IF PEEK(P) < 32 THEN F'* = CHR* (PEEK (P) + 64) ELSE

P* = CHR*(PEEK(P)) 5 0 30 L.PRINT P*J 5 P = P + 1 J NEXT H 5040 LPRINT" " 5050 NEXT V 5060 RETURN

Pain In the Exhaust

The article "FCC Regulation of Personal- and Home-Computing Devices," by Terry Mahn (September 1980 BYTE, page 180) has consequences for buyers and sellers of microcomputer systems that are far-reaching and not widely realized.

Compliance with the new FCC (Federal Communications Commission)

regulations and the associated paperwork, testing, and certification are expensive. Personal- and business-computer systems will be more expensive after the first of January, 1981, because the consumer will be paying for compliance with these regulations.

Let me first point out that, as a licensed radio engineer, I must agree that restricting radio emissions from personal home-computing devices is both neces

26 February 1981 © BYTE Publications Inc

THE NEW RELIABLES

We used to be known as Industrial Micro Systems and we made the best micro componentry around.

Now we're IMS International, and the best components in the business are an integral part of the best and broadest micro-based business system line around. Ours.

As a dealer, here is a sales package with real teeth.

Easy to sell.

Reliable. Engineered equipment offering factory technical support a phone call away. (Though we have equipment in operation since 1975, yet to fail.)

Low cost —well under $10,000 complete —with the best margins and benefits in the industry. Face it, even the most impressive specifications are no replacement for profits.

Our systems are designed to meet the specific needs

of your business computer customers today and tomorrow. Our tested dealer sales package has been designed for you and your needs.

Tailored sales plan. National advertising backup. Point of purchase program. Protected territories. Guaranteed complete system deliveries in 30 days. 180-day warranty to your customers.

We have what you and your customer need.

The package is complete. New. Reliable.

To become part of our expanded dealer network in 1981, call Fred Williams (collect) 714/978-6966, or write us:

Boxl

2800 Lockheed Way international Carson City NV 89701

Circle 21 on inquiry card.

p-='/;:S

Well, to begin with, color graphics.

RCA's VP-3301 has unique color-locking circuitry that gives you sharp, jitter-free color graphics and rainbow-free characters.

Plus much more: Microprocessor control. Resident and programmable character set. Reverse video. State-of-the-art LSI video control. 20 and 40 character formats. RS232C and 20 mA current loop. Six baud rates. Eight data formats. ASCII encoding. Light-touch flexible-membrane key switches for reliability and long life. CMOS circuitry and a spill-proof, dustproof keyboard for hostile environments.

The VP-3301 can be used with a 525-line color or monochrome

monitor or a standard TV set through an RF modulator. It

serves a wide variety of industrial, educational, business and

individual applications including communication with time

sharing and data base networks such as those provided by

Dow Jones News/Retrieval Service, CompuServe and Source.

All this—for the low price of $369. And it's made by RCA. So

get the whole story about the surprising VP-3301 today. Write

RCA Microcomputer Marketing, New Holland Avenue,

Lancaster, PA 17604. Or call toll-free: 800-233-0094.

'Suggested user price. Monitor and modem not included.

©1980. RCA

28 February 1981 © BYTE Publications Inc

Letters •

sary and desirable. The impact of this restriction is not yet fully realized by businesses or consumers.

I will discuss both views. My company functions as an OEM (original equipment manufacturer), buying boards, cabinets, floppy disks, etc, from various companies and customizing these into systems for our customers. We are in a favorable location, where the FCC is a local telephone call away, and its testing labs, in Laurel, Maryland, are right up the street. As a business, what we have to do to legally advertise or sell a system after January 1, 1981, involves a lot of work and money. The testing and certification are beyond our inhouse capabilities, and the necessary spectrum analyzer—even to rent—is expensive. A lab in our area will do the testing for us for $1500. Necessarily, this forces us to raise our products' prices. There, then, is even more involved paperwork and such. Now, $1500 is not a lot to the Tandy Corporation, Apple Computer, or Hewlett-Packard, but it does represent a problem for the hundreds of small computer businesses.

Also, we believe our main selling point is S-100 compatability, whereby we can choose from the wide spectrum of available boards to customize a user's system. However, if we change anything that would affect RF (radio frequency) emissions (ie: substitute a different input/output or memory board), we must recertify the "new" configuration. This will defeat any flexibility we now enjoy. The key point is that larger manufacturers can easily absorb these expenses, and we "little guys" are forced to raise prices drastically, or go out of business.

For consumers, you'll be paying more for a system that is certified to meet RF emission/interference criteria. It is hard not to draw parallels with emission-control equipment required on automobiles. In principle, it is an excellent idea. In practice, it is a pain in the exhaust, and an expense.

Having presented the problem, let me suggest some approaches. Even though this matter has been studied by the FCC for three years, it is being sprung upon manufacturers rather quickly. I believe a period of evaluation by the industry— particularly the microcomputer "cottage industry"—is in order. I have mentioned this to the FCC and to my congressman. Also, I would be happy to discuss these issues with any other interested parties.

This issue represents a critical turning point for our industry and our hobby. I do not believe that many people are aware of the consequence.

Patrick H Stakem, President Interface Technology of Maryland POB 745 College Park MD 20740a

Circle 22 on inquiry card.

THE DAWN OF A NEW AGE

The 2nd Generation is here!

MEASUREMENT systems & controls proudly introduces its new and exciting "2nd Generation family of S-100* compatible products. Each has been specifically designed for use with multi-user and network operating systems such as MP/M, CP/NET, and OASIS. Every product is fully tested and burnedin, comes with a 1 year guarantee, and offers you features not currently available from any other source.

Z80 PROCESSOR BOARD — The most powerful CPU board available today. Outstanding features include 4MHz operation, high-speed serial and parallel I/O utilizing DMA or programmed control, eight vectored priority interrupts, and a real time clock.

MULTI-USER SERIAL I/O BOARD - For use in

expanded systems requiring up to eight additional serial I/O ports. Features include: 16 maskable

'All products meet the new IEEE standards.

Systems

vectored priority interrupts, RS-232C interfaces

with full handshake, asynchronous or synchronous

operation with asynchronous baud rates to 19,200.

Available in four or eight channel versions.

DOUBLE DENSITY

FLOPPY DISK

CONTROLLER BOARD

controls up to four 5V4inch or 8-inch disk drives using IBM soft sectored formats. It features 1K of on-board buffering, DMA controlled data transfers and the performance characteristics of the superior NEC 765 chip.

64K BANK SELECTABLE MEMORY BOARD

Features include I/O port addressing for bank

select with 256 switch selectable I/O ports for the

memory bank addressing. The memory is

configured as four totally independent 16K

software-selectable banks, with each bank

addressable on any 16K boundary.

"Attractive Dealer & OEM Prices"

See your nearest computer dealer, or

contact us for the complete story on

The 2nd Generation.

a Division of MEASUREMENT systems 8. controls

incorporated

867 North Main St. / Orange, Calif. 92668 (714) 633-4460 TWX / TELEX: 678 401 TAB IRIN

Hardware Review

Radio Shack's Daisy Wheel Printer II

Yvon Kolya, POB 22, Peterborough NH 03458

In August of 1980, Radio Shack introduced a series of new products, including a daisy-wheel printer capable of producing high-quality print for word-processing systems. Radio Shack named the device the Daisy Wheel Printer II.

I was fortunate enough to be among the first to receive one of the new Daisy Wheel Printer lis. I picked it up at the store only a week after ordering it.

Physical Appearance

As I expected, the printer had an attractive appearance, using the standard Radio Shack colors black and silver. However, much to my surprise, I found the printer to be constructed entirely of heavy-gauge cast aluminum. The only nonmetal parts were the miscellaneous knobs and switches, which were brought out to the surface of the cover for the user to manipulate, and a rubber platen. Upon opening it up, I discovered that the metal exterior was well supported by a cast aluminum interior frame, with a layer of foam rubber sandwiched between the two for sound absorption. Everything else seemed to be made of steel or chrome, except the pulley wheels, which were nylon. All in all, the printer appeared to be very solidly constructed. It was a bargain to get all this excellence for hundreds of dollars less than an equivalent letter-quality printer.

Connecting It

As soon as I had unpacked the printer from its shipping box, I plugged the carbon ribbon cartridge into place, a very simple operation, and then I pressed the print wheel

into position (also a very simple operation). When I connected the printer to my TRS-80 Model II and tried it out, it worked perfectly.

I borrowed a friend's TRS-80 Model I Disk System and tried it out with the printer. It also worked perfectly the first time.

Next I connected it to an Apple II-Plus computer, using its Parallel Printer Interface Card. Unfortunately, it did not work. After a little experimentation, I discovered that the problem was with the ROM (read-only memory) software on the parallel card. Normally, the Apple's software leaves the eighth bit of the data bus set high. When it's set low, the characters on the video display flash on and off. On the Centronics printers, and their look-alikes, this bit is ignored. On the Radio Shack printer, however, the eighth bit is used for the special characters. To correct this problem, I grounded the line for the eighth bit, and the printer then worked correctly with the Apple II-Plus. I could have used a software routine to correct this problem, but I felt this method would be quicker.

Printer Controls

There are two control switches on the front of the printer, an on-line/off-line switch and the pitch-control switch. There are three modes of pitch control: 10 cpi (characters per inch), 12 cpi, and proportional spacing. The pitch control used depends upon the type font mounted in the printer. For example, if the Courier 10 font daisy wheel is in place, this switch should be placed in the 10 cpi position. If the Prestige Elite font is used, the switch setting should be 12 cpi. The Madeleine font requires that the switch be set to proportional spacing. To some minor degree, the 10 and 12 fonts can be used at either the 10 or the 12 cpi switch setting, although using

30 February 1981 © BYTE Publications Inc

Circle 23 on inquiry card.

?>*

■%£>!

<f*

:^TV

«£$

m->

SM

£P^

E

ZORK is more than an adventure.

Zork'" is a computer fantasy of ultimate challenge. Unearthly creatures guard treasures beyond your imaginaf tion. Mazes confound your quest. So quicken your wits and pick your path carefully through the Great Underground Empire. The least likely object 7 may be the only thing that can save ,..*

your life. iSSSV

Yet, you can succeed. Discover the 20 treasures of Zork, return them to the Trophy Case and leave alive. But bring all the cunning and courage you can muster. Because in Zork, they take no prisoners . ..

Zork, The Great Underground Empire, was created by Infocom, Inc., and j±.\is available for 32K Apple* II and II

--Plus and 32K TRS-80'" Model 1 Level I —

K 11 disk systems. I Also new from Personal Software

is MONTY'" Plays Monopoly* which lets an Apple or TRS-80 play America's favorite board game with the family.

Arcade Classics is a new TRS-80 action game featuring Cosmic Raiders, Pinball, Ricochet and 8fc\ Blockade:"' A great way to ^,J\ have fun without feeding quarters into the machines

Zork, MONTY Plays MonJ3 opoly and Arcade Classicsmore fun and games with your computer, now joining our other Strategy Games: Microchess, Gammon Gambler, j Checker King, Bridge Partner and Time Trek. './ See these great strat

egy games at your Personal Software computer retailer. For the I dealer nearest you, call | Personal Software Inc. at 408/745-7841, or write 1330 Bordeaux Drive, Sunnyvale, CA 94086.

When you put your computer to work, use Personal Software'" Productivity Products: VisiCalc,'" DESKTOP/ PLAN" and CCA Data Management System. _ ■

"Wg

ft

I 4

v,

the 10 font at the 12 setting will make the letters appear cramped.

At the top of the printer are two levers, one on the right for releasing the grip of the platen on the paper, and one on the left for controlling the number of carbon copies (from 1 to 7) to be run through the printer.

At the rear of the printer are, once again, two switches. One switch is directly above the power cable, and it is used to turn the machine on and off. The other is over the interface connector; it is the self-test switch. The self-test switch prints out a series of characters to test both the printer and the print wheel.

Inside the printer, to the right of the cabinet, there is a three-position impression intensity control switch. It allows you to adjust the amount of energy used by the strike-hammer when printing.

Name

Audience

Daisy Wheel Printer

Computer owners desir

II—catalog number

ing letter-quality printout

26-1158

instead of dot-matrix

Use

Features

Letter-quality printer

Print speed: 43 cps;

carriage-return speed:

Manufacturer

300ms/13% inches (34.5

Radio Shack

cm); linefeed speed: 4

1 Tandy Center

ips; printing pitch choice

Forth Worth TX 76102

of yi0 inch, yi2 inch, or

proportional spacing;

Dimensions

linefeed pitch: % inch or

20.45 by 62.5 by 39.5 cm

Yi2 inch; fonts: 124 char

W20 by 24% by 15^0

acter positions on

inches)

double-daisy print wheel;

wheels: Courier 10

Price

(supplied), Prestige Elite

$1960

12 (not supplied; catalog

number 26-1421),

Hardware Required

Madeleine P S (not

TRS-80 Model I, II, or III

supplied; catalog number

computer, or any com

26-1422); characters per

puter capable of driving a

line: 136 characters at 10

standard Centronics

pitch, 163 characters at

interface parallel printer;

12 pitch; impression con

requires a printer

trol: high, medium, low;

computer cable, available

interfaces (physical):

from Radio Shack, for

eight parallel and one

whichever Radio Shack

strobe; code: Modified

computer the printer is to

ASCII; paper-feed

be used with.

mechanism: pinch-feed

platen; power

Software

requirements: 120 VAC,

None (if used with

50/60 Hz, 141 W 220

appropriate configuration

VAC, 50 Hz (for

of a Radio Shack com

European operation)

puter)

Hardware Options

Tractor feed, $249 extra

Documentation

38-page manual, 22 by 28

cm (8V2 by 11 inches),

includes schematics

Printer Attributes

This printer does not require special software for use. If you have the proper printer cable for your computer, you can use the printer immediately. While in BASIC, you can use it to print listings, or you can use it from within a program to deliver hard-copy information. If you have a word processor, such as Radio Shack's Scripsit or Michael Shrayer's Electric Pencil, you are really ready to go.

Unfortunately, both Electric Pencil and Scripsit are incapable of using all the features of this printer. For example, not all of the control codes accepted by this printer are used by these two word processors. The codes accepted by the Daisy Wheel Printer II are given in table 1.

Unfortunately, Scripsit will access only the carriagereturn-with-linefeed code (decimal 13) of this printer. The rest of the codes are not used.

Electric Pencil is only a little bit better in that it accesses the backspace feature (to perform underlining) in addition to the carriage-return-with-linefeed code.

Fortunately, BASIC is capable of accessing all of these codes (using the function CHR$(X)); the printer's manual provides several example lines of BASIC code that can be used to do this. Listing 1 shows the first step of a maze generated on the Apple II-Plus printed by this printer. A word of caution: if your BASIC program uses the top-ofform code (decimal control code 12), you will need a special driver program for this printer. This special program is available from Radio Shack free of charge.

Although BASIC can access all of the characters and control codes used by the printer, the TRS-80 in command mode is incapable of accessing either the special control codes or about thirty characters on the print wheel because the keyboards of the Tandy Corporation computers do not generate the necessary ASCII (American Standard Code for Information Interchange) codes.

The complete character set produced by the printer is shown in listing 2. Notice that there are several foreignlanguage characters, as well as special nonalphabetic

Listing 1: A test pattern to check registration. This pattern, which is made from vertical bars and underline characters, demonstrates the printer's capabilities of great printing accuracy.

Listing 2: The character set of Radio Shack's Daisy Wheel Printer I!. Some of the special characters can be printed only by sending special-character codes to the printer.

!"#$»& '()*+,-./0123456789:;<->?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]"_" 'abcdefghijklmnopqrstuvwxyz{|}~ag£u °'t"9®Hi5sue"f§¥A0Ut_a6uG

32 February 1981 © BYTE Publications Inc

Circle 24 on inquiry card.

"•I*

How to tell if it's a White Computer.

You see, it isn't always white. Until now, if you bought a White Computer it was dressed up as someone else's system. Mow the White Computer is available under its own nameplate.

And the features that make the White Computer the choice of many system builders also make the White Computer an excellent choice for you.

Features like White'sguaranteeto ship replacement parts within 24 hours of your telephone call. CP/M® and MP/M™ operating systems. Full upgrade routes to multi-user and hard-disk performance. (Like the 3-user 35 megabyte system shown.) And 8-bit or 16-bit configurations. Features that make the White Computer the reliable, high performance

system you need for business, or software development, or industrial control uses.

So if you buy a computer that's not white, it might still be White. But make sure. Because if it's not White, chances are you're paying more, for less computer.

White Computers are now available from computer dealers nationally. Call or write for more information, and the name of your nearest dealer.

CP/M is a registered trademark of Digital Research. MP/M is a trademark of Digital Research.

White Computer Company A 1876 Industrial Way Redwood City, California 94063 A 415 364 7570

Photo 2: The print-wheel mechanism. The print wheel is a double-daisy wheel (ie:. each prong of the wheel contains two or more characters, one closer to the center than the other). The mechanism is shown tilted back, which is the position used for changing the print wheel.

Code (decimal) Description

10

Linefeed, no carriage return

13

Carriage return with linefeed

27,10

Reverse linefeed

08

Backspace one character

15

Turn on automatic underline, all subsequent

characters will be underlined

14

Turn off underline

27,01

Space V60 of an inch

27,02

Space V30 of an inch

27,03

Space V20 of an inch

27,04

Space V15 of an inch

27,05

Space V,2 of an inch

27,06

Space 710 of an inch

27,14

Software set printer to '/,„ of an inch character

space mode

27,15

Software set printer to V,2 of an inch character

space mode

27,17

Software set printer to proportional spacing

27,28

Half linefeed

27,30

Reverse half linefeed

Table 1 Control codes accepted by the Radio Shack Daisy

Wheel Printer I!. Some of the operations are performed with

a two-code

sequence.

characters. Careful study of the type font indicates that the Courier 10 print wheel supplied with the printer is capable of printing both the French and German alphabets. That's a really nice feature, if your software will allow you to generate the required ASCII codes from the keyboard.

Another worthwhile feature of this printer is a printer optimizer. If a series of linefeeds, either positive or negative, are received by the printer within 10 ms of each

DEALERS...OEM USERS.

Call on Monday... your North Star computer will be

dldltkmmil by Thursday.

WHOLESALE PRICES AVAILABLE.

Authorized stocking distributor for North Star. GBC also maintains ready stock on the following products and software:

• Centronics

• Perkin-Elmer

• Epson

1 NEC Spinwriter • Turnkey North Star Business Software

(609) 424-0465

£1UM) inc.

General Business Computers

2020 Fairfax Avenue Cherry Hill, New Jersey 08003

other, they are temporarily stored until a character code or control code is received, after which they are all performed at once. That is, if ten linefeed codes are received at less than 10 ms intervals, they are automatically stored. Upon receipt of the eleventh code, which in this example is not a linefeed, the printer moves the paper the full distance of ten linefeeds, rather than the distance of one line ten times, as other printers do.

As a last note, the documentation says that the printer uses a multistrike carbon ribbon. This means that the ribbon is advanced very slowly, with each key striking on almost the same place as the previous keystroke. Unfortunately, when the end of the cartridge is reached, you cannot rewind it and reuse the ribbon unless you disassemble the cartridge and rewind the ribbon from the takeup reel to the supply reel by hand. This is a very tedious and messy process. (I did it once when I desperately needed a printout and did not have an extra cartridge available.)

Summary

• Radio Shack's Daisy Wheel Printer II is a full-featured printer capable of providing high-quality print; it is totally suitable for use in word processors.

• The printer accepts the Centronics-standard parallel connector; thus it can be driven by any computer capable of driving a Centronics-type parallel printer (although some modification may be necessary to prevent the printing of special characters that use the eighth bit high).

• The print wheel supplied provides 124 different characters, not all of which can be produced from the standard ASCII keyboard unless a special softwaredriver routine is written and used.

• The printer is constructed of heavy-gauge metal and should be capable of heavy-duty use for a very long and useful life.

• According to a label on the back, the printer was made in Japan for Radio Shack. If someone had told me that Radio Shack would be selling a word-processor printer as solidly built as an NEC (Nippon Electric Company) printer or a Diablo Spinwriter, only much cheaper, I wouldn't have believed it. Now I do.B

34 February 1981 © BYTE Publications Inc

Circle 25 on Inquiry card.

* * * A PERCOM BULLETIN * * *

Adapter for TRS-80* computer eliminates disk read errors

Garland, Texas — Harold Mauch, president of Percom Data Company, announced that the company is marketing a simple plug-in adapter for TRS-80* computers that corrects a design deficiency in the disk controller circuit.

The problem, which causes disk read errors, has been traced to Tandy's reliance on a circuit internal to the FD1771 controller IC to perform the function of separating clock and data pulses.

As explained in the Backgrounder, use of the internal chip circuit for reliable data-clock separation is a design shortcut which the manufacturer of the controller IC warns against.

The Percom solution, a PC card adapter called the SEPARATOR™, eliminates the problem by substituting an explicit data separator circuit

SEP.. 1771

CLOCK PiN ?b

SEP. 17 71 DATA PIN 2 7

1771

S p 1 N 2 5

RATOR

DATA CO. INC.

Percom adapter fixes TRS-80* \computer disk controller.

— one which has been used The SEPARATOR™ is

reliably in Percom disk con- installed without modifying the

trailers since 1977 — for the host system. The user merely

internal IC separator circuit. removes the FD1771 IC from

the host controller, installs the IC in the DIP socket on the SEPARATOR™ card, and plugs the adapter into the vacated socket of the host controller.

Percom cautions that opening the Expansion Interface of the TRS-80* computer, which is required to install the SEPARATOR™, may void the computer's limited 90-day warranty.

The SEPARATOR™, which sells for $29.95, may be purchased from Percom dealers or ordered direct from the factory. The Percom tollfree order number is 1800-527-1592.

Payment for mail orders may be made by certified check, cashier's check or money order, or charged to a Master Card or VISA account. Texas residents must add 5%

SaleS taX. Circle 26 on Inquiry card.

Percom Mini-Disk Drives Store More, Cost Less.

Percom mini-disk drives store more data, are more reliable, yet a 40-track Percom drive costs $100.00 less than a 35-track Tandy drive.

You can store over 102 Kbytes per disk

on Percom TFD-100™ 40-track drives, over

197 Kbytes per disk on TFD-200™ 77-track

drives. A patch — supplied free on minidiskette — upgrades

TRSDOS* for operation with the newer 40- and 77-track drives.

Both TFD-100™ and TFD-200™ models are available in

one-, two- and three-drive configurations.

Prices start at $399 for a single-drive TFD-100™, $675 f ora single-drive TFD-200™. Drives are supplied with heavy-duty power supplies. Metal enclosure is finished in compatible silver enamel.

See your nearby Percom dealer or order direct by calling toll-free 1 -800-527-1592. circi„ *a on inquiry c»rd.

Five-Inch Disks Store More Than Eight-Inch Disks!

Garland, Texas — June 25, 1980 — Percom Data Company has begun production of a double-density disk controller adapter for TRS-80* Model I computers.

Harold Mauch, president of Percom, made that announcement here today, saying that data storage capacity using the adapter and double-density disk operating system — which is included — can be increased to as much as 354 Kbytes per minidiskette.

By comparison, the maximum storage for larger eight-inch disk systems used with the TRS-80*

Circle 322 on Inquiry card.

Model I computer is about 290 Kbytes.

Mauch said the PC card adapter, which plugs into the controller chip socket of the computer Expansion Interface, works equally well for either single-density or double-density storage, and users may continue to run programs under TRSDOS*, OS-80™ and other single-density operating systems with the adapter installed.

Price, for the plug-in adapter, the TRSDOS*-like double-density DOS and a utility for converting files and programs from single- to double-density format is $219.95.

BACKGROUNDER

CRC ERROR! TRACK LOCKED OUT!

by the Technical Staff Percom Data Company

This problem started while we were studying an annoying problem with the TRS-80* computer. Disk drives sold by Percom are realigned and tested before shipment. We noticed, however, that some disk drives would pass the Percom inspection but just would not work reliably on the inner tracks with a TRS-80* computer. These drives were within the manufacturer's specifications, and would function perfectly on other disk systems Percom manufactures — "perfectly" here meaning more than 50 million bytes read without error!

The disk read data separation arrangement in the TRS-80* computer Expansion Interface uses an internal data separator of the FD1771 disk formatter/controller IC. Use of the FD1771 internal data separator is not recommended by Western Digital, the IC manufacturer. The following note appears on page 17 of the FD1771 datasheet:

Internal data separation may work for some applications. However, for applications requiring high data recovery reliability, WDC recommends external data separation be used.

PRICES AND SPECIFICATIONS SUBJECTTO CHANGE WITHOUT NOTICE.

We suspected the data separator because the problem was most severe on disk inner tracks where storage density is highest and data separation is most critical.

To prove our point, a technician breadboarded a standard Percom data separator circuit, and configured it to plug directly into the FD1771 IC socket of the TRS-80* computer controller.

When connected to the TRS-80* computer, a troublesome drive functioned perfectly! We ran a BACKUP utility many times and never got a track lockout. Before we added the external data separator circuit to the computer, this same drive would always lock out tracks, and would have difficulty reading from the inner (higher number) tracks.

The Percom data separator circuit fixes the mini-disk controller of the TRS-80* computer. The type of drives being used is irrelevant; the circuit eliminates disk read errors resulting from the inability of the Tandy controller design to reliably separate clock and data signals when reading high density inner tracks.

Circle 323 on Inquiry card.

PERCOM DATA COMPAMY, IMC. 211 N. Kirby Street Qarland, Texas 75042 (214) 272-3421

"traiemark o I Percom Data Company, Inc. 'trademark of Tandy Radio Shack Corporation which has no relationship to Percom Data Company.

An Extremely

Low-Cost Computer

Voice Response System

A computer speech-output system can be built which requires no A/D (analog-to-digital) or D/A (digital-toanalog) converters, no multiple-pole filters, no complex hardware, very little software, and yet produces speech which is quite intelligible even to untrained listeners.

A data rate of 9600 bps (bits per second) produces speech quality and intelligibility acceptable for most hobbyist applications. This means that a 400-word vocabulary can be stored on one side of a single-density 8-inch floppy disk, the average word duration being 0.5 seconds. Similarly, the 16 hexadecimal digits, 0 thru F, can be spoken from the data stored in only 8 K bytes of memory, the average word duration for these digits being 0.4 seconds. The memory need not be high quality, and slow memory devices or components with a few random bit failures can be used. Thus, for limited vocabularies, the MIMIC speech processor may be the lowest-cost computer speechprocessing system available. Other applications include:

• two-tone telephone-signal decoding

• alarm signal

• automatic word recognition by computer (using software pattern matching against stored speech samples)

• sound effects

• computer-generated musical tunes

• metronome

• rhythm generator

James C Anderson

c/o MIMIC Electronics

POB 921

Acton MA 01720

About the Author

James C Anderson is a graduate student at the Massachusetts Institute of Technology. He is the inventor of the MIMIC speech processor, a device similar to the one described in this article, which is manufactured and marketed by MIMIC Electronics Company.

A good deal of redundancy is maintained at 9600 bps since, for example, a lower data rate is achievable by the linear predictive coding method (typically 2400 bps). This implies that slightly defective memory circuits can be used for storing the speech, with essentially no degradation in speech quality (do not base the cost of a speech-storage system on high-priced memory). The low cost, high reliability, ease of use, and massproducibility of this system make it a good choice for consumer products such as video games. Imagine what a computer could say when it finds itself losing a game (onomatopoetic responses such as "awww" are also possible).

Sixteen spoken

words can easily

be stored In 8 K

bytes of memory.

There are basically two reasons why speech-storage memory can be inexpensive:

• The manufacturer's yield on perfect circuits plus slightly defective circuits (those with 1 % of the bits bad) will be higher than the yield on perfect circuits alone.

• Memories with slow access times can be used. An access time of 10 ms is more than adequate, and circuits of this sort can be purchased at prices far below those of standard semiconductor memories.

Hardware

The technique to be used here is called differentiated, infinitely

clipped, and integrated speech. Figure 1 on page 38 is a diagram of the essential hardware. Model speech is input through a microphone and a preamplifier (ICl). The unprocessed analog-speech signal is then used as input to a compressor consisting of an operational amplifier (or op amp, IC2), two diodes, and two resistors.

The compressor has a pseudologarithmic characteristic and greatly amplifies low-level signals while somewhat attenuating high-level signals. In this system, the compressor acts as a simple automatic gain control, making the amplitude of the speech signal at the compressor output less dependent upon such things as the human speaker's voice loudness and distance from the microphone.

The output of the compressor goes to a simple R/C (resistor/capacitor) differentiator which has a pole at approximately 8 kHz. The differentiator performs quite well over the entire range of speech frequencies from 100 Hz to 5 kHz (300 Hz to 3 kHz is considered "telephone quality" bandwidth for speech signals).

The differentiated analog-speech signal is then applied to a comparator (IC3) which acts as a zero-crossing detector, or infinite clipper, and turns the analog speech into a digital bit stream. A resistor is in series with the noninverting input to compensate for the input bias current of the comparator, thus preventing distortion due to "center clipping" of the signal. Only a small amount of DC offset potential in the comparator produces a large degradation in speech intelligibility.

This would complete the speech data-input path except for one problem: when no speech is present, the

36 February 1981 © BYTE Publications Inc

Speech Processing

Many techniques now exist for speech processing or digitization (the encoding, storage or transmission, and subsequent decoding of data for speech signals). Some techniques have definite advantages over others depending upon the application.

For example, phoneme synthesizers, which are essentially electrical analog models of the human vocal tract, can produce speech from very low data rates (600 bps (bits per second) or less) and are often used in systems where bandwidth or memory is at a premium. By contrast, timedomain techniques such as delta modulation require greater bandwidth (9600 bps or more) and are popular when a mass-storage device (eg: a disk drive) is available. Time-domain techniques simply record speech-signal parameters as a function of time, and may or may not make use of human-vocal-tract characteristics to help reduce memory or bandwidth requirements.

Cost constraints often determine which type of speech processor will be used in a system. Synthesizers can be costly both in terms of the initial hardware investment and in the programming and testing time required to convert words into phoneme strings. Neither of these costs is likely to be reduced significantly. It is often more cost-effective to invest in equipment of general utility, such as a floppy-disk drive, and use a low-cost time-domain speech processor. Many forces are acting to drive down the cost of mass storage. For example, optical recording technology has produced a 30 cm disk with storage capacity of 10 billion bits and dataaccess times compatible with speech-processing requirements. Assuming the speech data has been sampled at a rate of 16,000 bps, such a disk can store enough data to produce speech continuously for more than a week.

Many of the time-domain techniques for speech processing have significant drawbacks. Pulse code

modulation, as used in telephonequality systems, requires a high data rate (64,000 bps) and is therefore seldom considered for present-day computer speech applications. CVSD (continuously variable slope delta) modulation produces good-quality speech from a 16,000 bps data stream, and several manufacturers have recently introduced CVSD integrated circuits (MC3417 by Motorola, HC-55516 by Harris Semiconductor, and FX-209 by Consumer Microcircuits of America are examples). However, all the CVSD units are sole-sourced (ie: noninterchangeable with other units).

Each of these components requires a considerable amount of support circuitry for operation, including a power supply, microphone preamp, audio power amp, and complicated filter s which use precision (1%) capacitors and resistors. Perhaps the greatest drawback to CVSD is the fact that the speech data stream which a CVSD chip produces is meaningful only to another CVSD chip.

For example, if the highly encoded CVSD speech data is to be used for automatic word recognition, it must first be decoded by some rather time-consuming software before any operations such as frequency analysis can be performed. CVSD data also proves to be difficult to "conference" (mix) in communication networks, when several users are talking simultaneously to a single listener.

When time-domain techniques are used to store a large vocabulary in memory, it often becomes a difficult and timeconsuming task to reproduce the words in the vocabulary at the same volume level. This occurs because it is nearly impossible to hold the microphone in the same manner and to speak always at the same volume level when originally recording the vocabulary. It is also difficult to add new words to an existing vocabulary for the same reason. A similar problem arises when attempting automatic speech recognition with a computer, since variations in volume produce

variations in the speech data pattern. Such variations must usually be eliminated by a lengthy amplitude-normalization process in software.

The MIMIC Speech Processor presented in this article is a lowcost time-domain system which has a relatively low bit rate. Using only standard components, the MIMIC Speech Processor requires minimal external hardware for operation. The data produced is not highly encoded, and is therefore easy to analyze and use in communication networks. The MIMIC Speech Processor automatically normalizes the amplitude of all audio input signals, and is therefore not subject to the problem of volume variation.

Speech Intelligibility

A common method for evaluating speech intelligibility is the "articulation test." Typically, a person reads a list of syllables or unrelated words to an "untrained" group of listeners (recognition ability improves with practice), and the percentage of items identified correctly is taken as the articulation score. By choosing test material representative of the sound statistics of a language, a realistic test of the system can be made. Word-articulation scores for speech which has been differentiated, infinitely clipped, sampled at a 10 kHz rate, and integrated (in that order) are in the neighborhood of 90% for trained listeners.

When words are used in sentences, contextual information is present which leads to considerably higher articulation scores. To test your system, try recording the sentences "Joe took father's shoe bench out," and "She was waiting at my lawn." Together, these sentences contain all of the fundamental sounds in the English language that contribute toward the loudness of speech.

February 1981 © BYTE Publications Inc 37

Figure 1: Speech-processing hardware. Model speech information is input through a microphone and preamplifier. The analog signal is processed by compressor and differentiator circuits, and is then applied to a zero-crossing comparator. The result is a serial data stream in which the bit width is modulated to reflect the input frequency. A squelch circuit is provided to disable the processor output when no speech signal is present.

Ai

fi1

comparator (IC3) puts out unpleasant high-frequency noise. This problem is overcome by controlling the processed speech-data signal with a squelch signal.

The squelch circuit uses amplitude information to shut off the data stream through IC4a. When the overall magnitude of the unprocessed input signal is above a certain threshold value, the circuit quickly enables the data to pass. Op amp IC5, diode Dl, and the R/C output filter form an envelope-detector system which follows the positive peaks of the unprocessed speech signal. A comparator with hysteresis (IC6 and its voltage-divider feedback network) is used to give the squelch circuit a fast attack response, but a slow decay characteristic. Thus, the differentiated and infinitely clipped digital speech data stream is created, and squelched when necessary.

The processed speech, in the form of a bit stream, may then be sampled by a computer or other digital hardware at a rate of approximately 10 kHz. The information may be stored in some type of memory, and used later to produce speech.

To reproduce stored speech, the information is dumped at a 10 kbps rate. The speech-output hardware is a filter consisting of IC4c and an R/C network which has a pole at approximately 16 Hz. The buffer (IC7) feeds an AC-coupled power amplifier (IC8) with volume control. The speech produced by this digital recording system has essentially been differentiated before storage, then integrated upon playback.

Quality

Although the storage requirement is typically 10,000 bits for each second of speech, the effective amount of storage required can be reduced somewhat by using phoneme concatenation. For example, the spoken word "seven" can be stored as an "s" sound plus an "eh-vun" sound. The same "s" sound can also be used in other words such as "six " ("s" plus "ick" plus "s"). Similarly, one recording of the word "teen" will allow you to generate "seventeen" with a simple program which outputs "s" plus "ehvun" plus "teen."

This method, unfortunately, will not always produce acceptable speech. When "dog" is broken up into "duh" plus "aw" plus "guh," the

38 February 1981 © BYTE Publications Inc

resulting audio does not sound like the intended word. This is due to the fact that in natural-sounding speech, the end of one phoneme often blends into the start of the next (but not always, as was shown in "seventeen"). If all of the phonemes are recorded separately, some method is needed to blend them together—a formidable task.

The speech quality of this system is similar to a single-side-band radio signal which is not quite tuned in. The speech produced is quite intelligible yet rather "mechanical" sounding. However, upon listening to speech produced by this system, several people have remarked that it "sounds just like you'd expect a computer to sound when it talks." Thus, it seems to have good public acceptance as far as quality is concerned.

Theory

Why does such a simple system work? The answer is not particularly simple. However, an understanding of the theory can point to methods for improving the speech quality and can also give a feel for the system's limitations. During World War II, it was discovered that a large amount of peak clipping could be impressed on a speech signal with the speech remaining at least moderately intelligible.

Infinite clipping is a process which preserves only the zero-amplitude axis-crossing information of the speech waveform (ie: the process tells us whether the signal is positive or negative). The intelligibility of an infinitely clipped speech signal can be

dramatically improved if the clipper is preceded by a differentiator circuit. A simplified conceptual diagram of the hardware is presented in figure 2, which omits the squelch circuit. The system input /(f) in figure 2 corresponds to the compressor output (IC2) of figure 1.

The spoken word "seven" can be stored as an "s"

sound plus an "eh-vun" sound.

Mathematically, taking the derivative of a function and equating it to zero yields the local maxima and minima (peaks and valleys) of the original function. For example, assume that the system input in figure 2 is a sine wave, /i(f), as shown in figure 3a on page 40. This sine wave is differentiated so that the cosine wave, /1(f), of figure 3b is present at the input to the comparator. Notice that whenever /[(f) equals zero, as at f = 7r/2, the original function ft(t) is at a peak or a valley.

In the next step of processing, the comparator acts as an infinite clipper. The comparator output is high when /'(f) is greater than zero, which means that the original function /(f) has a positive slope and is rising from a valley to a peak. Similarly, for /'(f) less than zero, the comparator output is low, which means /(f) is going from a peak to a valley. When /'(f) equals

zero, a critical point is occurring and the comparator output is changing. The comparator output is an infinitely clipped version of /'(f) as shown in figure 3c. This may be sampled and stored as digital information.

An approximation to the original function /(f) can be obtained by integrating the stored digital information (see figure 3d). Note that only a triangular-type waveform can be obtained at the integrator output because the input to the integrator is always a bivariate (two-level) waveform. However, a triangle wave is a close approximation to a sine wave. In fact, the triangle wave of figure 3d is given in Fourier-series form as:

(4/7r) [sin f (l/25)sin 5f + ...)]

(l/9)sin 3f + (l/49)sin It

The components other than the fundamental (sin f) can be considered as contributions to distortion and can be reduced by filtering. In general, a DC offset may also be present, but any offset can easily be eliminated in the actual implementation simply by using AC-coupled amplifiers. In summary, the system of figure 2 will provide a triangle wave which can only approximate the original sine wave.

Amplitude Decoding

In the system of figure 2, the frequency of the "reconstructed" waveform (at the output) will be the same as the original input frequency. However, the output waveform's

-31

>f(u

SAMPLE BIT STREAM AT 10 kHz RATE

111

STORE DATA IN MEMORY

OUTPUT BIT STREAM AT 10 kHz RATE

COMPARATOR

COMPUTER

T

X

^> +

f'tt) ifcm

-O

DIFFERENTIATOR

INTEGRA TOR

Figure 2: Diagram of the processing concept. This simplified diagram omits the squelch and compressor stages of figure 1. The process is easy to follow: any analog input is differentiated and clipped before storage as a digital bit stream; upon playback, the bit stream is simply integrated to recover the original waveform information.

February 1961 © BYTE Publications Inc 39

1

n

\y\y\/\X\

40 February 1981 © BYTE Publications Inc

Figure 3: The basic process is illustrated on the first four waveforms. If a sine wave (a) is fed to the processor (fM =sin t), the wave will be differentiated to produce a cosine wave (b) (f[(t)=cos t). Notice that the cosine wave crosses zero whenever the sine reaches a peak. This is also reflected in the output of the infinite clipper stage (c) where the waveform may be expressed as: f'M/\f[(t)\. At this point, the information may be stored digitally. An approximation of the original signal (f(t)) can be obtained by integrating the stored information to produce (d):

f'M

dt

Although the output waveform has the same frequency, the amplitude is not always accurately reproduced, since the comparator has a constant amplitude output regardless of input signal level. If the signal shown in (e) is fed to the speech processor (f2(t) = sin 6.5t), the differentiator will produce the wave of (f) (f'2(t) = 6.5cos 6.5t). The zero-crossing comparator produces the square wave of (g) (fi(t)/\fi(t)\), which may be recorded quite accurately. When this information is played back, the wave of (h) will be produced:

f'M

dt

The amplitude is reduced because the integrator stage is essentially a low-pass filter. The same process is performed on more complex waveforms as shown:

(i) h(t) = sin t + — sin(6.5t + 2.3) 6.5

(J) f'i(t) = cos t + cos(6.5t + 2.3)

fM

(k) fL,ppJt)

\W\

(!) \Hct,„Jt)dt = i~ J \fl

m)

\M)\

dt

Note that the overall wave shape and relative amplitudes are well preserved.

1 2 3

amplitude will diminish as the frequency increases; and it will do so regardless of the input amplitude. For example, assume that the input to the system is /2(f) = sin 6.5t, as shown in figure 3e. The output of the differentiator is then /2(f) = 6.5 cos 6.5t, which is a large-amplitude cosinusoid (see figure 3f). This signal is applied to the comparator and the square wave of figure 3g results, with an

February 1981 © BYTE Publications Inc

41

amplitude independent of the inputsignal amplitude.

The square-wave signal is now run through an integrator, which drastically diminishes the amplitude of the signal (see figure 3h). This is so because an integrator acts as a lowpass filter, and causes a signal's amplitude to diminish in inverse proportion to its frequency (ie: it attenuates higher frequencies by 20 dB per decade of increase in frequency). Thus, the amplitude of f2(t) was not preserved in the reconstruction, even though the frequency was.

The clipped-speech

approach presents

an alternative to

more complex

and costly systems.

We can get an accurate reconstruction of both frequency and relative amplitude only if we guarantee that the input waveform will diminish in amplitude as a function of its frequen

Listing 1: The author's MIMIC driver. Assembled on Cromemco's CDOS for Z80s, this routine should work equally well on any 8080-based microcomputer. As noted in the comments at the top, this software should produce a 10 kbps data rate for systems with a 2 MHz clock.

0001

EXAMPLE:

MIMIC DRIVER PROGRAM

0002

8080 OR Z80 INSTRUCTIONS

0003

ASSUMES 4 K OF MEMORY AT LOCATIONS 0 TO FFF

0004

ASSUMES MIMIC INTERFACED AT PORT B3 HEX

0005

ASSUMES 2 MHZ CPU CLOCK

0006

RESULTING SPEECH DATA RATE IS 10 KHZ

0007

0000

0008

ORG

0

PROGRAM STARTS AT ZERO

0000

214800

0009

/IN

LD

HL.BUF

ADDRESS BUFFER MEMORY

0003

0E08

0010

LD

C,8

INITIALIZE BITCOUNT

0005

DBB3

0011

vM

IN

A.0B3H

DIG OUT ACTIVE?

0007

17

0012

RLA

CHECK FOR BIT 7 SET

0008

DA0500

0013

JP

C.V1

WAIT FOR IT

000B

DBB3

0014 '

72

IN

A.0B3H

GET DATA BIT FROM MIMIC

000D

IF

0015

RRA

SHIFT BIT ZERO INTO CARRY

000E

7E

0016

LD

A,(HL)

GET DATA BYTE

000F

IF

0017

RRA

PUT BIT INTO BYTE

0010

77

0018

LD

(HL),A

STORE DATA IN BUFFER

0011

0D

0019

DEC

C

COUNT BIT

0012

C21E00

0020

IP

NZ.V3

DONE WITH BYTE?

0015

0E08

0021

LD

C,8

RESET BITCOUNT

0017

23

0022

INC

HL

MOVE POINTER

0018

7C

0023

LD

A,H

SET UP FOR COMPARE

0019

FE10

0024

CP

010H

AT 4 K BOUNDARY?

001B

CA2400 0025

JP

Z.VOT

YES, NOW PLAY BACK DATA

001E

CD4100

0026 '

73

CALL DEL

100 MICROSECOND WAIT

0021

C30B00

0027 0028

JP

V2

LOOP AGAIN

0024

214800

0029

</OT

LD

HL.BUF

ADDRESS BUFFER MEMORY

0027

0E08

0030

LD

C,8

SET BITCOUNT

0029

7E

0031 '

/T2

LD

A,(HL)

GET DATA BITS

002A

D3B3

0032

OUT

0B3H.A

OUTPUT DATA TO MIMIC

002C

OF

0033

RRCA

ROTATE BITS IN DATA BYTE

002D

77

0034

LD

(HL),A

STORE DATA BYTE

002E

0D

0035

DEC

C

COUNT BIT

002F

C23B00

0036

JP

NZ.VT3

DONE WITH BYTE?

0032

0E08

0037

LD

C,8

RESET BITCOUNT

0034

23

0038

INC

HL

MOVE POINTER

0035

7C

0039

LD

A,H

SET UP FOR COMPARE

0036

FE10

0040

CP

010H

AT 4 K BOUNDARY?

0038

CA2400

0041

JP

Z.VOT

YES, REPEAT AD INFINITUM

003B

CD4100 0042 '

/T3

CALL DEL

100 MICROSECOND WAIT

003E

C32900

0043 0044

JP

VT2

LOOP AGAIN

0041

0609

0045

DEL

LD

B,9

CALIBRATE CONSTANT FOR ]

0043

05

0046

D2

DEC

B

0044

C24300

0047

JP

NZ.D2

LOOP UNTIL DONE

0047

C9

0048 0049

RET

0048

00

0050 0051

3UF

NOP

START OF BUFFER MEMORY

0049

(0000)

0052

END

cy. For example, (l/a)sin(af) is such a signal, when a is an arbitrary real (nonzero) constant. Thus, if we had applied (l/6.5)sin 6.5f to the system (instead of just sin 6.5f as in the previous example), the output would have been a reconstructed waveform of both proper frequency and amplitude.

The system of figure 2 is therefore limited to reconstruction of signals which fall off in amplitude by 20 dB/decade. Figures 3i, 3j, 3k, and 31 show what the system does to a more complicated signal which meets the restriction. The important thing to note is that the wave shape (and hence the frequency content) of the original signal is faithfully reproduced, and the relative amplitudes are maintained.

Speech signals (eg: a voltage waveform produced by a microphone whose output is linearly proportional to pressure) generally have amplitude components which drop off as a function of frequency by about 20 dB/ decade. This is true for both shortterm (125 ms) and long-term (a minute or so) measurements. Hence, one would expect the system of figure 2 to be capable of reproducing fairly natural-sounding speech which, indeed, it does.

Actually, differentiated-clipped speech is just as intelligible as differentiated-clipped-integrated speech (ie: no new information is produced by simply integrating the bivariate waveform at the comparator output), but it is very unpleasant to listen to. Some types of music can also be recorded using this system, with recognizable melodies and harmonies.

Distortion

Distortion may come from several different locations in this system of speech recording and playback. If, for example, the input signal does not have components which fall off in amplitude by exactly 20 dB/decade, there is no hope for an "exact" playback using the circuit of figure 1. This situation arises when several persons are speaking simultaneously at different levels of loudness. The voices tend to mask or distort each other. A similar situation occurs when one person talks in a noisy environment. Another source of distortion comes from the fact that the system can produce only ramp-type

42 February I'M © BYTE Publications Inc

waveforms at its output, no matter what the input looks like.

With additional hardware and software, these problems can be greatly overcome, resulting in an improvement in speech quality. If, instead of a simple squelch circuit, the slowly varying amplitude-envelope signal is sampled with an A/D converter, and if this data is used to amplitudemodulate the constant-level clipped speech signal when it is reproduced for output, the quality of the signal is improved. However, the overall data rate required is approximately 15,000 bps, and requires additional hardware. The system of figure 1 is about the best we can do in terms of simplicity and cost when it comes to low-bandwidth speech processing.

Sample Rates

If one is to use clipped speech as a digital recording technique, distortion due to a finite sampling rate must be considered. Figure 1 shows a typical system for recording a vocabulary of selected words which may later be used for computer voice response. Experiments have shown that highly intelligible speech can be obtained with a sampling rate of about 10 kHz. Note that this sampling rate is an experimental result and has nothing to do with the wellknown sampling theorem, which states that the rate of sampling must be at least twice the highest frequency to be recorded, in order to ensure an accurate reproduction. Here we are essentially sampling a square wave, which is not a band-limited signal.

To understand why the 10 kHz sampling rate is adequate, consider the fact that the human ear loses resolution at high frequencies. For example, the note A above middle C has a fundamental frequency of 440 Hz. The next note above it (A sharp) has a frequency of 440 X 1\[1 , or approximately 466 Hz. The highest A on the piano, which is 3 octaves above 440 Hz, has a frequency of 23X440 or approximately 3520 Hz. Similarly, the highest A sharp has a frequency of 23 X 466, about 3729 Hz.

The difference between 440 Hz and 466 Hz sounds the same as the difference between 3520 Hz and 3729 Hz, even though the actual frequency difference is 26 Hz versus 209 Hz. Thus, our ability to resolve frequencies deteriorates rapidly with increasing frequency. In the case of clipped

speech, time quanta of about 0.1 ms are adequate and the ear cannot easily discern errors introduced in the frequencies which are reproduced. Sampling clipped speech at rates much higher than, say, 20 kHz merely wastes computer memory while offering no appreciable improvement in speech quality.

Final Note

It appears that clipped speech techniques can be used in cases where a limited-vocabulary computer voice response is needed. In terms of simplicity, ease of implementation, and low cost, it is probably optimal. For persons on limited budgets such as students, hobbyists, and even professional electrical engineers (who see applications for computer speech output but would have trouble justifying a large investment), the clippedspeech approach presents an alternative to more complex and costly systems. ■

References

1. Flanagan, J L. Speech Analysis, Synthesis, and Perception. New York: Academic Press Inc, 1965, pages 137 thru 139, 238 thru 240, and 270 thru 273.

2. Fletcher, Harvey. "Some Physical Characteristics of Speech and Music." The Bell System Technical Journal, July 1931, pages 349 thru 373.

3. Graeme, Tobey, and Huelsman. Operational Amplifiers. Burr-Brown, McGraw-Hill Book Co, 1971, pages 267 thru 268.

4. Licklider, J C R. "The Intelligibility of Amplitude-Dichotomized, Time-Quantized Speech Waves." The Journal of the Acoustical Society of America, Volume 22, Number 6, November 1950, pages 820 thru 823.

5. Licklider, J C R, and G A Miller. "The Perception of Speech." Handbook of Experimental Psychology, pages 1040 thru 1074. Psychological Abstracts, Volume 25, 8040, December 1951.

6. Licklider, J C R and Irwin Pollack. "Effects of Differentiation, Integration, and Infinite Peak Clipping upon the Intelligibility of Speech." The Journal of the Acoustical Society of America, Volume 20, Number 1, January 1948, pages 42 thru 51.

7. Young, L L and Jeanette Goodman. "The Effects of Peak Clipping on Speech Intelligibility in the Presence of a Competing Message." IEEE Acoustics, Speech & Signal Processing, 1977, pages 216 thru 218.

Attention

BOTE

Readers:

Would You

Like To Write For

onComputing?

The amount of intriguing newsoftware and hardware appearing on the personal-computing market has increased dramatically in the past few months. onComputing is looking for wellwritten software and hardware reviews about small-business programs and systems, games, scientific programs, simulations, and even "homebrew" programs created by our readers.

If you're a good writer, onComputing is interested in your opinions. We are looking for concise reviews written with the nonspecialist in mind—no computer jargon, please (unless you explain it completely in the review).

Do you have an interesting application for your personal computer? We'd like to hear about it, too!

All submissions should be typed and double-spaced. Payment is made at a rate of up to $50 per magazine page. Send your manuscript today. It may be just what our readers have been waiting for!

Send for our free information sheet about review guidelines to:

Review Guidelines Chris Morgan Editor-in-Chief onComputing 70 Main St Peterborough NH 03458

(Unsolicited manuscripts should be accompanied by a stamped, self-addressed envelope.)

February 1981 © BYTE Publications Inc 43

Ciarcia's Circuit Cellar

A Computer-Controlled Tank

Steve Ciarcia

POB 582

Glastonbury CT 06033

My guess is that when you first scanned the title of this article and a few of the photos, you immediately recognized Milton-Bradley's Big Trak. Perhaps it was one of the gifts your children received during the holidays.

Big Trak, shown in photo 1, is a

Copyright © 1981 by Steven A Garcia. All rights reserved

computer-controlled, motorized toy tank. Commands to move, to turn, and to fire the "photon cannon" are programmed by a user (via a keypad) into the tank's control system. After the user presses the "Go" key, Big Trak takes off, executing the stored command sequence.

Big Trak's keypad contains a key for each command. Some commands are completed with a single key

stroke, while other commands require multiple keystrokes for the entry of parameters. A list of command functions appears in table 1.

Commands may be chained and carried out sequentially. For example, pressing the sequence: Forward, 2, Left, 3, 0, Hold, 1, 0, Fire, 3, Go, causes the tank to drive forward 2 feet, pivot 180°, wait 1 second, and then fire three cannon blasts. This se

Photo 1: The Big Trak microprocessor-controlled, user-programmable tank, sold by the Milton-Bradley Company.

44 Febiuaiy 1981 © BYTE Publications Inc

quence is four commands. Big Trak can hold sixteen commands.

Considering this month's Circuit Cellar title and the description thus far, you may think this article is about Big Trak and the microcomputer control system it employs. You are half right. Big Trak is indeed the tank mentioned in the title. However, the word "Computer" in "ComputerControlled Tank" refers to your personal computer, rather than the microprocessor inside the tank!

For a long time I have been interested in robotics. I have always fantasized about building a robot to do simple tasks. I am sure that many others have similar interests. Unfortunately, due to the high expense and the mechanical expertise required, most of us never get beyond the idea stage.

Playing with Big Trak is a tease. It is not a robot, nor can it be converted into one. However, it has features that are fascinating as well as aggravating for robot-building procrastinators like myself. Big Trak has a control system that memorizes commands and coordinates a mechanical drive. It converts simple keystrokes into complex movements combined with light and sound effects.

While the microprocessor program that controls the tank is interesting, it is the price/performance ratio of the mechanism that is impressive. Big Trak incorporates a two-wheel/twomotor gearbox. The wheels turn synchronously for forward or backward motion and contrariwise for turns. Left and right turns are precisely definable (to a resolution of 1 part in 60). This drive mechanism would take many hours to fabricate if you were building it from scratch.

For die-hard robotics types, this is kid stuff. EXACTLY! But, to someone with just a passing interest, the capabilities of this $50 toy are fascinating. With a little ingenuity, it could serve as a test bed for robot enthusiasts on a tight budget. It could also serve as a school project combining programming and actual control of a mechanical device.

If only it could be linked with a larger computer and remotely controlled!

This idea sounded like a fun project, so I decided to write an article on converting Big Trak to remote control. The result is an interface that allows complete wireless control of

the tank's operation from your computer keyboard. Virtually no modification is required to your computer if it already incorporates a serial I/O (input/output) port and 300 bps (bits per second) modem.

Writing the control program isn't hard. Commands are communicated as LPRINT CHR$(X) statements in BASIC. (For example, an LPRINT CHR$(81) fires the photon cannon.) A program which demonstrates this is included. (See listing 1.)

At the other end of the link, a circuit is installed in the tank to receive control commands from your computer and simulate the user pressing the keypad. This is not a specialized interface applicable only to Big Trak; the receiver has useful applications elsewhere. It is designed in two sec

tions: a tank interface specifically for this application and a general-use wireless receiver/demodulator. The receiver/demodulator can easily serve as a wireless serial RS-232C extension for your computer in other applications. Don't care to string wires for a printer located in another room? Use this receiver interface up to 200 yards from the computer.

All this will be explained in detail, but first, back to Big Trak.

Inside Big Trak

Big Trak gets its control capability from a TI (Texas Instruments) TMSlOOO-series 4-bit microprocessor. This single 28-pin CMOS (complementary metal-oxide semiconductor) integrated circuit contains programmable user memory, ROM

Single Entry: Test Clr CIs Ck Go

— Tests tank operation by moving and tiring cannon

— Erase all previous command entries

— Erase last entry only

— Execute last command entry immediately

— Execute complete command sequence

Multiple Entry:

Backward/Forward

Turn (Left/Right)

Fire

Hold

Repeat

— How far? Enter 1 to 99 feet.

— How much? Enter 2-digit turn value.

— How many shots? Enter 1 to 99 shots.

— How long? Enter 0.1 to 9.9 seconds.

— How many steps back? Enter 1 to 15.

Table 1: Summary of commands as entered on Big Trak's keypad. Some commands are completed with a single keystroke, while other commands require multiple keystrokes (to enter qualifying data, such as how far to travel). The actual Big Trak keypad is shown in photo 3.

.».4,1,11.1 XI. J HUIlJillllJ

Haifa!* t

Photo 2: The microprocessor control system inside Big Trak. The 28-pin integrated circuit is a TI TMSlOOO-series 4-bit microprocessor. The smaller package is a hex digit driver used in this application to power the various tank functions.

February 1981 © BYTE Publications Die 45

R8-*R94

R10-*

GND

Kl

KZ

K4

K8 —

INIT

074064

054

04 4

034

"W

28 27 26 25 24 23 22 21 20 19 18 17 16 15

TMS1000/ TMS1100

-»-R7 -►■R6 -»-R5

► R4 ►R3 ►R2

*-Rl

»-R0

•► 9V

4 OSC 2

4 0SC1

»-00

»-01

-♦02

Figure 1: Pin usage of the 77 TMS1000 4-bit microprocessor. The TMSlOOO-series processors all have the same instruction set, differing in the number of pins used for I/O and in the amount of memory contained in the package.

Pin Name

K1,K2,K3,K4 OO thru 07 RO thru R10 0SC1, 0SC2 INIT

Description

data input data output control output timing power-on reset

Type

input

limited code output

output

input (resistor/capacitor)

input

PIN 23

Q Q A A A C

PIN 8<3~

PIN 7<C3~

PIN 6<^]

>X

-L

OUT

X

°X

X

•x

X

=x

X

-x

X

•X

X

X

•x

X

•X

X

•X

X

•X

X

»x

X

-X

X

-X

X

CLS

°x

X

>x

X

'X

-1

1

°x

X

CLR

'X

X

FIRE

*x

X

°x

X

HOLD

X

I

PIN 5<CJ

Figure 2: Schematic diagram of the Big Trak's keypad matrix. The column lines are connected to the R-series output pins on the TMS1000, and the row lines are connected to the K-series input pins. The physical structure of the keypad can be seen in photo 4.

(read-only memory), and I/O capability. The low cost (under $1 in large quantities) makes this the product of choice for many simple applications such as computer games and appliance controls.

The TMS1000 microprocessor series is actually a family of fifty-odd devices. They all share a common instruction set. The differences are the number of I/O pins and the amount of on-board memory. The package of Big Trak's 28-pin microprocessor, shown in photo 2, is marked only with a "house" number. It is most likely either a TMS1000 or a TMS1100. The only difference between these two components is the amount of memory they contain. The TMS1000 has 1 K bytes of ROM and 32 bytes of programmable memory, while the TMS1100 has twice as much of each memory.

As shown in figure 1, the microprocessor has four dedicated input lines and nineteen dedicated output lines (OO thru 07 and RO thru RIO). The eight data outputs, OO thru 07, are wired in an unusual way and can be set to only 32 out of the usual 256

values possible with an 8-bit code. This is because the O-series outputs receive only the 4-bit values from the accumulator and the status flag (1 bit) as inputs. The enabled range of the 32 values (out of the 256) is mask-programmed during manufacture of the

The "wireless extension cord" can be used with other peripheral devices besides Big Trak.

circuitry on the silicon chip.

The R-series output lines, on the other hand, are treated as eleven control outputs. Each R output line can be set or cleared individually.

The Big Trak uses these lines to read input data from the keypad, generate sound effects, light up the "photon cannon," and coordinate the operation of the two motors.

Because the TMS1000 is a low

power device (about 90 mW), it cannot directly drive a motor. A second integrated circuit (an SN75494) and a few transistors facilitate the connection. The 75494 is a hex digit driver primarily intended to interface CMOS devices to common-cathodeconfigured LEDs (light-emitting diodes). While the tank uses no LEDs, the 150 mA drive-current capability of the 75494 makes it particularly suitable in this application.

Connection of the keypad (shown in photo 3) to the microprocessor is straightforward. The keypad is actually a matrix of processor I/O lines. Outputs RO thru R5 and inputs Kl, K2, K4, and K8 form a 4 by 6 matrix (only twenty-three keys are functional—the In key has no contacts) as shown in figure 2. The K signals are the rows, and the R signals are the columns.

Such a keypad operates on a scanned-matrix principle. The processor alternately places a signal on each R line and reads the four inputs for any completed circuit (which shows a key being pressed). Entering a command, therefore, is simply a

46 February 19S1 © BYTE Publications Inc

The Big Trak can

serve as a test bed for

robot enthusiasts on a

tight budget.

process of shorting one of the cross points of the matrix.

The keypad has no springs, magnets, or raised buttons. It is nothing more than two photo-etched plastic sheets with conductive traces, separated by a thin insulator. At the cross points of the matrix, the insulator has a cutout. Any pressure on the keypad surface over this point flexes the plastic and shorts the two contacts, completing the circuit. Photo 4 shows the structure of the keypad.

Practically speaking, any connection between a column and a row of the matrix will be perceived as a valid data input to the processor. For example, if you use a clip lead to connect pins 8 and 26 on the processor package, it will accept this as a Go command and commence operation. This concept is the premise of my remote-control circuit.

External Keyboard Control

Remote control of Big Trak starts with an interface that attaches to the processor and functions in place of the keypad. Figure 3 shows the schematic diagram of a circuit that does this. The prototype is shown installed over the processor board in the tank. (See photo 5.) Its location with respect to the tank layout is better shown in photo 6.

The integrated circuits IC2 and IC3 are 8-channel type-CD4051 CMOS multiplexers. The 6 matrix column lines are attached to IC2, and the 4 row lines are connected to IC3. The selection of 1 of the 6 column lines and 1 of the 4 row lines is determined by the address-input lines A, B, and C on each integrated circuit. A total of 5 address bits are required. While a sixconductor cable (5 bits of data and ground) strung between the computer and the tank for parallel communications would work, it is hardly efficient as remote control. Serial communication is better, for a number of reasons.

The components ICl, IC4, and IC5 function as a 300 bps serial-to-parallel

Photo 3: Commands are entered into Big Irak's memory through this keypad on the top of the tank.

converter which operates on 9 V (note the use of the General Instrument AY-3-1014A UART, a universal asynchronous receiver/transmitter). Data comes into pin 20 of IC3 at 300 bps where it is reconverted to parallel format. Bits 0 thru 2 (DO thru D2) go to IC2, and bits 4 and 5 (D4 and D5) go to IC3. The choice is not arbitrary. By selecting these particular bits as the address inputs, the CMOS switches can be set by binary codes that correspond to ASCII (American Standard Code for Information Interchange) characters. This makes the

interface more flexible, since its functions can be exercised directly through characters output by use of the CHR$(X) function in the BASIC language. The necessary codes are common, printable characters and will not interfere with machine operation. (In some BASICs, the CHR$(X) function can cause strange things to occur, depending upon the value of X. In my computer system, sending a CHR$(127) clears the screen and resets the cursor.) Choosing printable codes also aids troubleshooting. Table 2 lists the twenty-three codes

February 1981 © BYTE Publications Inc 47

used in this interface. For example, sending an "R" (with the output statement LPRINT CHR$(82)) tells the tank to make a right turn.

Oscillator IC5 (a 555 timer) is tuned for 4800 Hz. This sets the communication data rate at 300 bps. A rate of 110 bps is set by changing the oscillator frequency to 1760 Hz.

Operation is straightforward. The UART is hard-wired for 8 bits of

data, no parity bit, and 1 stop bit. When a character is received, the data-output line becomes active and the DAV (data available) line goes high. One section of IC4 serves to delay the reset pulse to the RDAV (reset data available) input. This produces a 10 ms strobe signal which closes the CMOS switches. (While the data rate may be 300 bps, time must be allotted between characters to

Photo 4: A rear view of the keypad, showing its construction. The keypad consists of two plastic sheets containing photo-etched conductors separated by a layer of insulation. At the locations of the function keys, the insulation has a circular cutout through which the two conductive layers can touch when pressure is applied.

Photo 5: The prototype of the Big Trak control interface of figure 3. It is mounted on top of the tank's processor board and is powered by the tank's 9 V battery. The interface contains a 300 bps serial-to-parallel converter which directs the operation of the CMOS switches attached across the keypad matrix.

allow the tank control system to respond. The effective data rate is more like five commands per second.) Whatever points were addressed on IC2 and IC3 will be electrically connected. The tank will then either store or execute the command, depending upon what it is.

Functionally speaking, you could stop right now. If you don't mind a two-wire cord running from your computer to the tank, you can control it with just the circuit so far described. Simply set your serial output port at 300 bps and feed its signals directly to pin 9 of IC4 in the interface. This, in fact, was the way I had to test the circuit before I went on to the next step.

Constructing a "Wireless Extension Cord"

The next step is, of course, the real fun part of this project. Since we can now command the tank through serial-character transmissions, it is only natural to consider eliminating the wire and using wireless communication.

Let's take stock. We have a tank that for all practical purposes is remote-controlled. All we have to do is send TTL (transistor-transistor logic)- or CMOS-level serial characters to it. These characters, in turn, come from BASIC LPRINT CHR$(X) statements, the output of which is transmitted serially. On the computer side, we have a serial output, and on the tank side we have a serial input. Connecting the two requires an "extension cord," either physical or ethereal.

One method, shown in the block diagram of figure 4, uses radio transmission. The approach is not as strange as it might initially seem. The serial output from your computer is FSK (frequency-shift keyed) modulated and transmitted. Somewhere at a remote location, a receiver picks up this transmission and demodulates it. The reconstructed serial data is fed into the remote device, in our case, the Big Trak control interface.

Please note the following: because this interface uses standard serialdata rates and voltage levels, any wireless communication device we design to accommodate computer/ Big Trak communication will also work for any other similar-rate communication. The computer doesn't know whether it is "talking" to a tank

48 February 1981 © BYTE Publications Inc

Meet ttie Tiger with a biager bite.

Introducing the remarkable 132-column Paper Tiger™ 560. The first full-width matrix printer to give you fully formed characters for a low $1695.*

The new 560 features a staggered ninewire ballistic type print head that overlaps dots in both horizontal and vertical planes. It bi-directionally prints up to 150 dense, text quality characters per second.

The 560 also features a reliable cartridge ribbon that lasts up to four times as long

presents a breakthrough in matrix printini ering the user excellent print quality wit! ce of a matrix printer. Employing a uniq red column" head manufactured by Integr creates high quality printouts by overla

Paper Tiger 560 Print Sample

as spool and cassette ribbons, separate heavy-duty stepper motors to drive the print head and advance the paper, plus true tractor feed.

And famous Paper Tiger performance comes with every new 560. Like fixed or proportionately spaced text, programmable tabbing and business forms control, automatic text justification, print formats to 220

columns, parallel and serial interfaces, selfdiagnostics, and more. All inside the most compact printer of its kind.

Need more stripes? Dotplot,™ our highresolution raster graphics package, is standard on every 560.

For data processing, word processing and small business applications, this is your Tiger. The business-sized Paper Tiger™ 560.

It's a Tiger you can count on.

Call TOLL FREE 800-258-1386 (In New Hampshire, Alaska and Hawaii, call 603-673-9100.) Or write: Integral Data Systems, Inc., Milford, NH 03055.

Tiger 560

■Up) Jlntegral Data Systems, Inc.

'Suggested U.S. retail price.

Circle 27 on inquiry card.

"PIN 21^}

5.1 K

YPICAL FOR 6)

CONNECTIONS TO BIG TRAK TMS 1000 MICROPROCESSOR

eO

10K

+9V

A

'20K

;0.022/iF MYLAR

DIS

RESET

IC5

OUT NE555

TSLD

TRIG

4800 Hz

(300bps)

Number

IC1 IC2

IC3 IC4 IC5

Type

AY-3-1014A

CD4051

CD4051

CD4049

NE555

12

11

10

19

IC1

AY-3-1014A

UART

CS

NP

NB2

NB1

RDE SWE RESET TSB EPS

SI RDAV

37

16

21

18

rft

IC4 CD4049

>0.1^iF

I-9V A

38

36

+ 9V

1

16 16 1

9V

t

+ 9V

100K AAft

GND

3

7,8

7,8

8 1

A

SERIAL DATA INPUT FROM FIGURE 7

Figure 3: Schematic diagram of the Big Trak remote-control interface. This circuit is installed inside the tank, replacing the function of the manual keypad. The address-input lines on each of the two CD4051 8-channel multiplexers select the rows and columns of the keypad matrix.

The AY-3-1014 A UART is a product of General Instrument Corporation, Microelectronics Division, 600 WJohn St, Hicksville NY 11802.

COMPUTER TTL/RS-232C SERIAL OUTPUT

MODULATOR

ANTENNA

V^V

TRANSMITTER

SERIAL INPUT TO REMOTE DEVICE (BIG TRAK)

ANTENNA

i

RECEIVER

Figure 4: Conceptual block diagram of a typical wireless communications link.

or to a remote printer. The "wireless extension cord" depicted in figure 5 can just as easily be attached between the computer and any output peripheral device.

Figure 5 outlines a simple way to accomplish this communication. At

the computer, an FSK modulator converts the 1 and 0 levels to 2025 Hz and 2225 Hz tones. These tones are transmitted using an inexpensive 49.86 MHz walkie-talkie. At the receiving end (in this case, the Big Trak), another walkie-talkie receives the

tones and a demodulator reconverts the tones to logic levels which are fed to the UART/control interface.

Figure 6 is a schematic diagram of an answer-type modem modulator. The assembled circuit is shown in photo 7. Serial data from the computer is fed into pin 1 of IC2, as shown. A logic 1 input produces a 2225 Hz tone, and a logic 0 input produces a 2025 Hz tone. These tones are amplified by IC3 and are directly fed to the walkie-talkie transmitter, through a connection across its speaker.

Figure 7 is a diagram of the circuit required at the receiving end. It consists of an originate-type modem demodulator and a walkie-talkie receiver. The guts of the walkie-talkie are removed from its case and mounted in the same enclosure with

50 February 1981 © BYTE Publications Inc

At $7951 how tough can these new Tigers be?

Introducing the new Paper Tiger™ 445 with the most rugged printing mechanism ever put in a low-cost matrix printer.

The 445 comes with a reliable ballistic-type print head and an advanced cartridge ribbon that lasts four times longer than many cassette or spool ribbons. Two separate heavy duty motors drive the print head and advance the paper. Plus you get true tractor paper feed.

And the new 445 gives you the performance you expect from the Paper Tiger family of printers. You can software-select character sizes, print 80- and 132-column formats, adjust paper width and length, even generate six-part business forms. All at unidirectional print speeds to 198 characters per second.

Need more stripes? Specify DotPlot™, a sophisticated raster graphics option.

If you've got an Apple**, TRS-80*** or other personal computer, get your paws on the tough new Paper Tiger™ 445 from IDS.

The people who invented low-cost matrix printing just growled.

Call TOLL FREE 800-258-1386 (in New Hampshire, Alaska and Hawaii, call 603-673-9100.) Or write: Integral Data Systems, Inc., Milford, New Hampshire 03055.

HI

KX33

Tiger 445

w£p) J Integral Data Systems, Inc.

Circle 28 on inquiry card

'Suggested U.S. retail price. "Apple is a trademark of Apple Computer Inc. "TRS-80 is a trademark of Radio Shack, a division of Tandy Corp.

the modem board. Photo 9 shows the receiver mounted in the bottom of the box. The modem board is mounted on stand-offs over the receiver, and batteries are placed along the edge and under the board, as shown in photo 10.

The audio output of the walkietalkie is tapped from speaker leads; a 10-ohm resistor should be substituted for the speaker if you don't wish to hear the tones. This audio signal is connected to the modem preamplifier input. It is next sent through a band

pass filter and limiter, which maximizes the signal level yet keeps it under the saturation point of the demodulator. The demodulator, IC3, is an XR2211 monolithic PLL (phaselocked loop). It is set to work at 2025 and 2225 Hz. The output of the demodulator is a logic signal that is compatible with the UART in the tank controller.

The basic circuits shown in figure 6 and 7 were originally presented in the Circuit Cellar article titled "A BuildIt-Yourself Modem for Under $50"

Photo 6: Big Trak undergoing modification. The interface circuit of figure 3 may be seen inside, in front of the keypad.

(BYTE, August 1980, page 22). I refer you to that article for a more complete explanation of modem communication. (See also "BYTE's Bugs," BYTE, October 1980, page 332, and November 1980, page 112.)

Wireless remote control in an automated-house application was discussed in "Handheld Remote Control for Your Computerized Home," BYTE, July 1980, page 22.

The printed-circuit boards shown in photos 7 and 10 are the production modem boards originally offered as a kit with components for those people interested in constructing their own modems from the August article. These circuit boards are still available and were used to construct the interface described in this article. A text box at the end of this article tells how to order one of these boards.

The completed interface is a fairly neat package. While it is large in comparison to the five-integrated-circuit assembly inside the tank, it can still be toted along behind Big Trak by using the Big Trak Transport, the tank's cargo trailer. A cable and jack connect the receiver to the controller in

Photo 7: The modulator section of an answer-type modem. The serial data output from the computer is modulated according to an FSK scheme into audio tones with frequencies of 2025 and 2225 Hz.

Photo 8: The output of the modem modulator is connected by a cable to this walkie-talkie (a Radio Shack number 60-4001) for transmission to the receiver on the Big Trak. The connection to the transmitter section of the walkie-talkie is made across the speaker terminals, with a 10-ohm resistor inserted in the circuit in place of the speaker. A phono jack installed on the front of the walkie-talkie facilitates the connection.

52 February 1981 © BYTE Publications Inc

Circle 29 on Inquiry card.

BRAIN

Once in a great while someone comes along with a simple improvement for an already great product. Take our SuperBrain, for example. Really a simple concept. A high-powered, low cost microcomputer packaged in an attractive desk top cabinet. So how do you improve on that?

WE DID IT...

It wasn't enough that our SuperBrain had such standard features as twin double density 5%" drives with over 300,000 bytes of disk storage. A full 32K of dynamic RAM - expandable to 64K in seconds. A CP/M* Disk Operating System which assures compatibility to literally hundreds of application packages presently available. A crisp, 12" non-glare screen with a full 24 line by 80 column display. A full ASCII keyboard with a separate keypad and individual cursor control keys. Twin RS232C serial ports for fast and easy connection to a modem and/or a printer. And, dual Z80 processors which operate at 4 MHZ to insure lightning-fast program execution. No, it wasn't enough. So we made it better.

ANNOUNCING SUPERBRAIN QD...

Our new OD model has all of the features of our phenomenally popular SuperBrain with the addition of double-sided disk drives and an extra 32K of dynamic RAM. So, for only a modest increase in price, you can order your next SuperBrain with more than twice the disk and memory storage capability. But, best of all, the new OD model has the same tough, rugged construction and exceptional quality that made our SuperBrain such a success.

HOW DID WE DO IT?

The secret of SuperBrain OD's incredible disk storage lies within our new double-density doublesided disk drives. A total of nearly 720,000 bytes of data are formatted on two specially designed 5%" drives. And that's more than enough to get you started with most serious small business applications. And SuperBrain OD's standard 64K of dynamic RAM will handle even the most complicated programming tasks.

Of course, if you're into megabytes instead of kilobytes, you may think neither SuperBrain is right for you. Not so! Intertec offers 20-96 megabytes of hard-disk storage which connects in seconds to either the SuperBrain or SuperBrain OD. So, your original investment is always protected. As you grow. No matter how much your needs expand.

BUT IS IT RELIABLE?

Our best salesmen are our present users. Not only have SuperBrain users been impressed with the inherent reliability of the system, they tell us that no other microcomputer system available today offers such a unique modular design concept. Just about the only tool required to easily

maintain the system is a common screwdriver. And Intertec's total commitment to product service and customer support, with service outlets in most major cities, insures your original investment will be a valuable one for many years to come.

THE DECISION IS YOURS.

Whether your next SuperBrain is a regular model or our OD version, you will have the satisfaction of knowing you purchased what is becoming one of the world's most popular microcomputer systems. And regardless of which model you choose, you'll probably never outgrow it because you can keep expanding it.

So, call or write us today for more information. Intertec systems are distributed worldwide and may be available in your area now.

3

_ NTE3TEC

Cdata s systems.

2300 Broad River Rd„ Columbia, SC 29210 (803) 798-9100 TWX: 810-666-2115

* of DiQiialReseaith. Inc

7antenna

computer interface

1

V

TRANSMITTER (WALKIE -TALKIE IN TRANSMIT MODE)

ANSWER MODEM MODULATOR (2025-2Z25 Hz)

300 bps SERIAL INTERFACE

COMPUTER

RUNNING

BASIC

ANTENNA

WIRELESS EXTENSION CORD

TANK INTERFACE

RECEIVER (WALKIE -TALKIE IN RECEIVE MODE)

•N

t

■v

ORIGINATE

MODEM

DEMODULATOR

SERIAL-TOPARALLEL CONVERTER

CMOS SWITCHES

TANK KEYBOARD

Figure 5: Block diagram of the wireless remote-control system described in this article. FSK modulation is employed along with inexpensive walkie-talkies to create a "wireless extension cord."

ici

NE567

o.ooi^f;

>10K

300bps

SERIAL [Z> 4—(I

INPUT

' 2 a p-w^—(-4

1

r

30 K

1M

-wv

2.2M -A/W,—

33pF

mD8

lOaF

^lOOK —Jt WW

IC2 CD4011

0.01/iF ;

• 0.01>iF

"X\H

10K VOLUME

m m

220/iF

o-vf;

ion •

ion

V

w

WALKIETALKIE SPEAKER

m

rft

2N2222

Number

IC1 IC2 IC3

Type

NE567

CD4011

LM386

+5V GND

4

14

6

Figure 6: Schematic diagram of the modulator section of an answer-type modem. The assembled circuit is shown in photo 7.

In this FSK-modulation scheme, a logic 1 input produces an output frequency of 2225 Hz, while a logic 0 produces an output frequency of 2025 Hz. The output is connected across the speaker (which also serves as a microphone) in the walkie-talkie, which is connected to the transmitter section. Capacitors marked with an asterisk (*) should be Mylar type parts.

terface. The combination trailer is shown in photo 11.

tank/

Programming Big Trak from Your Computer Keyboard

Now that you have a remotecontrolled tank, you have to write a suitable control program. The complexity of the program depends upon the level of sophistication you desire. The interface was designed for simple interaction, and it doesn't require much. Complete direction can be ac

complished with as little as the following BASIC program:

100 INPUT A

110 LPRINT CHR$(A);

120 GOTO 100

In this program, the value of the variable A should be one of the 23 decimal values listed in table 2. The operator must keep track of the entry sequence, and Big Trak and the communication link must be powered at

all times, because commands are entered singly and stored only in the tank's control system.

A much more sophisticated BASIC program is shown in listing 1. This program allows the operator to assemble a command sequence offline with functional entries (Hold, Fire, etc) rather than coded inputs. In addition, the time needed to develop a command sequence becomes less of a problem, since power to the tank

Text continued on page 58

54 February 1981 © BYTE Publications Inc.

Circle 30 on Inquiry card.

Listing 1: A program in BASH ' tiuit ttlhnvs the operator to assemble a Big Trak command sequence using functional entries. The command sequence is stored within the host computer and is transmitted in its entirety to tiie Big Trak when the operator gives the Go command.

100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 300 310 320 330 340 350 360 370 380 390 400 410 420 430 440 450 460 470 480 490 500 510 520 530 540 550 560 570 580 590 600 610 620 630 640 650 660 670 680 690 700 710 720 730 740 750 760 770 780 790 800 810 820 830 840 850 860 870 880 890 900 910 920 930 940

REM ************ BIG TKAK HFIMOTE CONTROL PROGRAM ********** REM REM REM

REM Clear enough memory space for possible 16 command sequence FOR Q = 25000 TO 25048 :POKE Q,u :NEXT Q :REM Clear Memory Table REM

REM Load conversion tabic for ASCII 0-9 to tank code DATA 38,53,3 7,8 5,52,3 6,84,51,35,83 FOR W=0 TO 9: READ B(W): NEXT W REM REM

PRINT:PRINT:PRINT:PRINT"COMPUTERIZED REMOTE CONTROL":PRINT K=0 :REM Reset Command Counter

S=0:T=25000: POKE T,65: T=T+1 :REM Set first code in table REM it clear code

PRINT"Command list to be repeated each time (Y or N)";:INPUT C$ IF CS="Y" THEN C = l ELSE C=0 :GOSUB 990 :GOTO 300 REM REM

IF C=l THEN GOSUB 990 ELSE GOTO 310 PRINT:PRINT"Command";:INPUT AS IF A$="M" THEN GOTO 440 C" THEN GOTO 600 THEN GOTO 650 IF A$="R" THEN GOTO 720 IF A$="T" THEN GOTO 760 IF A$="F" THEN GOTO 820 IF A$="D" THEN GOTO 890 IF A$="G" THEN GOTO 920 IF A$="L" THEN GOTO 1290 GOTO 310 REM

REM Move Command

PRINT"(F)orward,(B)ackward,(L)eft,or (R)ight" IF B$="F" THEN X = 33 :COTO 500

GOTO 500

GOTO 550

IF A$ = IF A$="H"

: INPUT B$

IF B$="B" IF B$="L"

THEN X=34 THEN X=50

IF B$="R" THEN X=82 :GOTO 550

GOTO 300

PRINT"How many feet (1 to 99)";:INPUT Ql

IF Q1<=0 THEN 500

IF Ql>99 THEN 500

GOSUB 9 80

GOSUB 1090: GOTO 300

PRINT"Turn how many degrees (0 to 360)";:INPUT Ql :Q1=INT((Ql/360)*60)

GOSUB 980

GOSUB 1090 :GOTO 300

REM

REM Clear Command

K=0 :S=0 :T=25000 :FOR Q=25000 TO 25048 :POKE Q,0 :NEXT Q

PRINT"Stored sequence cleared Start Again":POKE T,65 :T=T+1

GOSUB 990 :GOTO 310 REM

REM Hold Command

X=49 :PRINT"Hold how many seconds (total times .lsec)";:INPUT Ql

IF Q1<=0 THEN 650

IF Ql>99 THEN 650

GOSUB 980

GOSUB 1090 :GOTO 300

REM

REM Repeat Command

X=67 :PRINT"Repeat how many steps";:INPUT Ql :GOSUB 980

GOSUB 1090 : GOTO 300

REM

REM Test Command

IF T<=25001 THEN 770 ELSE 790

LPRINT CHR$(68);:PRINT"TEST COMMAND TRANSMITTED"

GOSUB 990 :GOTO 310

PRINT:PRINT"CAN NOT EXECUTE EXCEPT AS FIRST COMMAND" :GOTO 300

REM

REM Fire Command

X=81 :PRINT"How many shots (1 to 99)";:INPUT Ql

IF Q1<=0 THEN 820

IF Ql>99 THEN 820

GOSUB 980

GOSUB 1090 :GOTO 300

REM

REM Dump (OUT) Command

X=86 :GOSUB 1090 :GOTO 300 REM

REM Command Transmitter

X=70 :PRINT"COMMAND CONTROL SEQUENCE IS BEING TRANSMITTED TO TANK"

PRINT :PRINT

GOSUB 1200 Listing 1 continued on page 58

SNAPP II EXTENDED DASIC A family of enhancements to the Model II DASIC interpreter. Part of the package originated with the best of APPARAT, INC.'s thoughts in implementing NEWDOS DASIC. The system is written entirely in machine language for SUPER FAST execution. The extensions are fully integrated into Model II DASIC, and require NO user Memory, and NO user disk space. The package is made up of the following six modules, each of which may be purchased separately;

XDASIC—Six single key stroke commands to list the first, last, previous, next, or current program line, or to edit the current line. Includes quick woy to recover DASIC program following a NEW or system or accidental re-boot. Ten single character abbreviations for frequently used commands: AUTO, CLS, DELETE, EDIT, KILL, LIST, MERGE, NEW, LUST, and SYSTEM. $40.00 XREF—A powerful cross-reference facility with output to display and/or printer. Trace a variable through the code. Determine easily if a variable is in use. $40.00

XDUMP—Permits the programmer to display and/or print the value of any or all program variables. Identifies the variable type for all variables. Each element of any array is listed separately. $40.00

XRENUM—An enhanced program line renumbering facility which allows specification of on upper limit of the block of lines to be renumbered, supports relocation of renumbered blocks of code, and supports duplication of blocks of code. $40.00

XFIND—A cross reference facility for key words and character strings, also includes global replacement of keywords. $40.00 XCOMPRESS—Compress your DASIC programs to an absolute minimum. Removes extraneous information; merge lines; even deletes statements which could nor be executed. Typically saves 30-40% space even for programs without REM statements! Also results in 7-10% improvement in execution speed. $40.00 ENTIRE PACKAGE ONLY $200.00

6160 Corporate Pork Dr. Cincinnati, Ohio 45242

, Coll Toll Free =

1 - 800 - 543-4628 Li'J Ohio residents coll collect (513)891-4496

All products now available to run with TRSDOS 2.0 TRS-80 is o trademark of the Radio Shack division of Tandy Corporation.

Now available for Model III

February 19S1 © BYTE Publications Inc 55

Introducing 7 data-shielding improvements from Verbatim for greater disk durability, longer data life.

Improvements to protect your data from head-to-disk abrasion. Improvements to shield your data against loss due to environmental conditions. Improvements that'll deliver a longer lifetime of trouble-free data recording, storage and retrieval than ever before possible.

It's all made possible by Verbatim, with these improvements:

1. A longer-lasting lubricant. Our new lubricant is more resistant to diffusion, to protect against data-destroying head-to-disk contact.

2. An improved liner. Our new liner cleans and

removes debris better. It also enables more lubricant to reach the recording head, protecting against head wear.

3. A thicker, more durable coating. Our disks have

a more uniform oxide coating for more adhesive and cohesive strength. We've also made it thicker; providing 10% more protective lubricant and an optimized signal resolution for the new recording heads. >.

4. Advanced polishing^ techniques. Our burnishing makes our disks uniformly smooth, for better data transfer, less head wear.

5. Reinforcing hub rings. All Verbatim disks are available with hub rings to aid in registration, eliminate slippage, reduce errors, and give

DD32-4000-W3

Datalife

\

rO

c 1980 Verbatim Corporation

formance of a lifetime!

better alignment repeatability.

6. Testing standards that go far beyond industry standards. Every Verbatim disk meets or exceeds the most demanding of IBM, Shugart, ANSI, ECMAand ISO standards-because we insist on Verbatim being the industry standard of excellence.

We analyze raw materials down to their molecular content. We subject every coating batch to more than 70 chemical, magnetic and electrical tests. Two separate test groups employ life-cycle tests using more than 400 disk drives from every manufacturer. And we conduct "worst case" testing of every bit of every byte of every track of every single disk. All to insure that Verbatim disks always pass the ulti

mate test: satisfying you. 7. A 100% Error-Free Certification that means more than just" 100% errorfree" Our certification isn't based on random sampling, or statistical averaging. Rather, it's based on extensively testing every single disk. So we can state that our disks really are 100% error-free, and back it up with a one year warranty.

"Try new Verbatim for the performance of a lifetime!

m

We play it back, Verbatim!

Circle 31 on inquiry card.

Circle 32 on inquiry card.

MICROPROCESSOR CROSS PASCAL RUNNING ON ALL PDP-11' LSI-11 SYSTEMS

WRITTEN IN MACROII SYMBOLIC P-CODE OUTPUT. . . USERMODIFYABLEAND . . .

LOW COST!!!

TARGET

MICROPROCESSORS

8085

6809

8048

68000

Z80

Z8000

9900

8086

6500

PDP-11

6800

OPERATING SYSTEMS

UNIX

RT-11

RSTS

RSX-11D

RSX-11M

RSX-11M-PLUS

IAS

ALSO FROM SYSTEM-KONTAKT

• DOWN LOADERS SIMULATORS CROSS ASSEMBLERS

SYSTEM-KONTAKT, Inc.

6 Preston Court • Bedford. MA 01730 U.S.A. (617) 275-2333

COMMANDS

: "

(F) ire"

(D)ump"

(G)o"

(D) ump"

NT"

(T)est"

Listing 1 continued:

950 PRINT:PRINT"Retransmit Same Control Sequence (Y or N)",:INPUTQ$

960 IF Q$="Y" THEN LPRINT CHR$(70);: GOTO 920

970 IF Q$="N" THEN 220 ELSE 950

980 A1=INT(Q1/10) :A=Q1-A1*10 :RETURN

9 90 REM

1000 PRINT"

1010 PRINT" (M)ove

1020 PRINT" (C)lear

1030 PRINT" (H)old

1040 PRINT" (R)epeat

1050 IF T<=25001 THEN PRINT"

1060 RETURN

1070 REM

1080 REM Store Command Code in Memory Table

1090 POKE T,X :T=T+1:K=K+1

1100 IF A+A1=0 THEN RETURN

1110 IF A1=0 THEN 1130

1120 POKE T,B(A1) :T=T+1

1130 POKE T,B(A) :T=T+1

1140 PRINT" Command Stored";

1150 IF K>=15 THEN GOTO 1160 ELSE 1170

1160 PRINT :PRINT"NEXT COMMAND MUST BE GO !" :RETURN

1170 RETURN

1180 REM

1190 REM LPRINT Command Sequence from Memory Table

1200 POKE T,X

1210 FOR E=25000 TO T

1220 D1=PEEK(E) :LPRINT CHR$(D1);

1230 FOR C=0 TO 100: NEXT C

1240 NEXT E

1250 PRINT"TRANSMISSION COMPLETE"

1260 RETURN

1270 REM

1280 REM Display codes stored in memory table

1290 FOR N=25000 TO 25048 :PRINT PEEK(N);" ";:NEXT N

1300 GOTO 300

Command Name

ASCII Character

Hexadecimal Code

Dec

mal Code

Forward

!

21

33

Backward

"

22

34

Right

R

52

82

Left

2

32

50

Clear (all)

A

41

65

Clear (last)

B

42

66

Hold

1

31

49

Repeat

C

43

67

Check

E

45

69

Fire

Q

51

81

Out

V

56

86

Test

D

44

68

Go

F

46

70

0

&

26

38

1

5

35

53

2

%

25

37

3

U

55

85

4

4

34

52

5

$

24

36

6

T

54

84

7

3

33

51

8

#

23

35

9

S

53

83

Table 2: Correspondence

of ASCII characters

to the twenty-th

ree Big

Trak corn

mand codes. The decimal

values of the ASCII characters are sen

t to the

transmitter

using the BASIC statement LPRINT CHR$(X).

Text continued from page 54:

and communication interface need to be turned on only when the sequence is to be executed. The Go command transmits the entire repertoire to the tank in one stream of data.

The data sent to the tank can in fact be seen in the sample run of listing 2. I used the same serial port designated for the wireless communications link to list the program. You'll note the

string of extraneous characters after "COMMAND SEQUENCE IS BEING TRANSMITTED TO TANK". "A!%1%&Q$25$!5&QTC%F" is the string sent to the tank by the CHR$(X) function. It ended up on the listing (inadvertently) because both devices (printer and tank) use the same I/O-port address. If you compare these characters to those in table 2, you will see that it represents the

58 February 1981 © BYTE Publications Inc

Circle 33 on inquiry card.

■mi—rmi

ngnnn mm mm mm mm mm ran pan mm mm mm hem fAiuui pnnng ronroi nnnmn

NEVER UNDERSOLD!

That's right. If you con find a lower price In this magazine for any of the Items listed in this ad, we will reduce our price below our competitor's price. See each box below to determine how much EXTRA we will cut off of THEIR price If we're not lowest. Please consider the competitor's shipping charges, OUR SHIPPING IS FREE!*

ft

FLOPPY DISKETTES & SUPPLIES

IF YOU CAN FIND A LOWER PRICE IN THIS MAGAZINE ON ANY OF THESE ITEMS, DEDUCT *.S0 FROM OUR COMPETITOR'S PRICE, THAT'S OUR PRICEl

Call For Quantity Discounts

Verbatim Diskettes (box of 10)

5'/." MD52501 soft.lOor 16 $26.50

5'/«" MD577-01 quad soft. 10 or 16 . . $33.00

8" FD34-1000 soft $30.00

8" FD32-1000 hord $30.00

8" FD34-8000 double density soft . . . $44.00 8" FD32-8000 double density hard . . .$44.00

Prlntwheels (specify style) Qume or Diablo $6.50

Label!

3'/, "xl5/16" (5000 labels) $18.75

Other sizes and quantities CALL

Rlbbonf

Diablo Hy Type I $4.95

Diablo Hy Type II $5.25

Qume Sprint $3.50

Centronics Zip Pack $3.95

MANY OTHERS CALL

ffff

PRINTERS

IF YOU CAN FIND A LOWER PRICE IN THIS MAGAZINE ON ANY OF THESE PRINTERS, DEDUCT S10 FROM OUR COMPETITOR'S PRICE, THAT'S OUR PRICEl

Epson MX 80

Okidata Microline-80.. . Okidata Microline-82 . . . Okidata Microltne-83 . .. IDS Paper Tiger 445G . . . IDS Paper Tiger 460G . . . Anadex DP-8000 (AP) . . .

CALL

$550

CALL

CALL

$775

$1193

CALL

$1395

Centronics 737 $799

NEC W/Sellum Bi.Dir. Board . . . $2595 Vista 25CPS $1595

CALL

. .CALL

Escon Interface

$545

Call For Other Printers

ffff

SOFTWARE, MODEMS & TRS-80 HARDWARE

IF YOU CAN FIND A LOWER PRICE IN THIS

MAGAZINE ON ANY OF THESE ITEMS,

DEDUCT 3V. FROM OUR COMPETITOR'S

PRICE. THAT'S OUR PRICEl

SOFTWARE

Microsoft

Basic Compiler $345

Basic-80 $319

Fortran-80 $399

Cobol-80 $599

Macro-80 $144

Pickles and Trout CP/M CALL

Grahm Dorian CALL

Peach Tree CALL

Magic Wand CALL

Supersoft CALL

PCD Pascal $350

Visicalc $124

Space Invaders $23

Adventure $26

Head cleaning kit $26

MODEMS

UDS 103CP $175

D-CAT $155

CAT $145

TRS-80 HARDWARE

Micropenis 77 track SUPER SALE $399

Lobo Drives CALL

Matchless Drives CALL

LJ =

LJ =

U3 =

U-i

\mt

4636 Park Granada Calabasas, Ca. 91302

©

0

Bijis Stars gja

MB

For phone c

(21 3) 8

rders CALL:

83-8594

l§" =

*_,_

3=

U^

mz

(u.

IF YOU CAN FIND A LOWER PRICE IN THIS MAGAZINE ON ANY OF THE ITEMS LISTED BELOW, DEDUCT 5% FROM OUR COMPETITOR'S PRICE, THAT'S OUR PRICEl (BUT IF YOU DON'T SEE IT, CALL FOR A PRICE—WE WILL BEAT EVERYBODY!)

S-100 HARDWARE APPLE HARDWARE

CALIFORNIA COMPUTER SYSTEMS:

16K Static RAM (Model 2016C) $349

32K Static RAM (Model 2032A) $599

64K Dynamic RAM (Model

2032A) $599

16K Static RAM (Model 2065A) $299

Main Frame (Model

2200A) $339

Floppy Disk Controller (Model

2422A) $339

4 Port Serial I/O (Model

2710) $CALL

2S+2P I/O (Model

2718) CALL

Z-80 CPU (Model 2810) $249

Godbout Econoram CALL

SD Systems Versa Floppy $279

Expando RAM $CALL

MicrosoftZ-eOSoftcard $259

SSM AIO $165

SYMTEC Apple Light Pen $219

CALIFORNIA COMPUTER SYSTEMS:

Parallel Interface (Model 7720A) $112

Asynchronous Serial Interface (Model

7710A) $149

Programmable Timer (Model 7440A) $149

I2K ROM/PROM Module (Model 7114 A) $75

Arithmetic Processor (Model 7811 A) $374

Synchronous Serial Interface (Model

7712A) $149

GPIB Interlace (Model 7490A) $281

3V. Didgil BCD A/D Converter $140

Centronics Printer Interface (Model 7728) . .$99 MOUNTAIN HARDWARE:

Super Talker $270

ROMWRITER $157

INTROL/X-10 $180

ROMPLUS+ $162

MUSICSYSTEM $499

Apple Clock $252

Lobo Drive $CALL

Vide* 80X24 $345

Andromeda $189

1-33

UJ

I I

L_I3

j ,:.=--

'FREE shipping on all orders over $20. Visa and Master Cord ly answer any questions on all of our hardware, software, a handling charges when arriving at never undersold price.

accepted. All never undersold offers good as supply lasts. Please add 2.00 for all COD orders. Please call for items not listed. We gladnd supply needs Qu anility discounts available. School purchase orders accepted. Please remember to figure competitors shipping and

Circle 32 on Inquiry card.

Circle 34 on inquiry card.

The

reachable

star.

ne & i /vi puts a quality 300 bps RS232 modem within reach of the smail computer user...the same modem selected by IBM, GE, RCA, and ADP. "Hie price? Under $200!

WeVe designed this compact modem with exclusive triple-seal acoustic cups, crystal controlled oscillator, and built-in diagnostics and indicators. It's packaged inside an attractive injection molded case...and we stand behind the STAR with a two year warranty!

STAR models are available that interface directly with RS232 machines such as APPLE, ATARI, and NORTH STAR or IEEE 488 machines such as the PET, and that operate with either U.S. or European frequencies.

commands entered during execution of the program.

The program here, of course, is designed more as a demonstration than as a functional illustration of computer intelligence. I don't play with these interfaces every day, and it is easy for me to forget the steps necessary to enter a program on the key

pad. By making it as idiot-proof as possible, by prompting the correct response, / can appear more intelligent when I demonstrate Big Trak.

In Conclusion

Big Trak will not create any earthshaking movement within the robot

Text continued on page 64

Photo 9: A second walkie-talkie is used in the receiving section of the remote-control hardware. The working parts of the walkie-talkie have been placed in the same enclosure that will shortly house the demodulator circuit. Here again, the speaker has been removed from the walkie-talkie and a 10-ohm resistor substituted.

Photo 10: The originate-type modem demodulator of figure 7 has been constructed on a printed-circuit board and placed in this box over the walkie-talkie circuit. The modulator section of the circuit board is not used in this application; therefore the integrated circuits used only by the modulator have been removed. The circuit board is mounted on stand-offs and is powered by two 9 V batteries. A shielded cable and a phono jack connect it to the tank-controller interface, mounted inside the Big Trak.

February 1981 © BYTE Publications Inc

New power at your fingertips.

Konan presents Hard Disk Control, Tape Control, and Serial I/O Boards for S-lOO computers.

Konan, known throughout the industry for its leading, innovative, guaranteed controllers for S-lOO systems, does it again. Now, it offers you more of the expanded capabilities you want,

Take your pick to suit your needs. There's the SMC-lOO™ storage module (SMD or CDC 9760 interface) hard disk controller. There's the HARDTAPE™ subsystem which offers Winchester hard disk control with tape back up. Or maybe you could use Konan's new KNX-500, software compatible with the AM-500*, for lO megabyte fixed/ removable media hard disks. The "DAVID" is Konan's new error-correcting intelligent disk controller for 51/4" and 8" Winchester hard disk drives. And the "ENHANCER" is an intelligent reel-to-reel tape controller with high speed printer port for spooling, offline sorts, copies, etc. Watch for new controllers coming soon!

Also, Konan introduces OCTOPORT™ and OMNIPORT™-two new serial I/O boards. OCTOPORT™, the 8-port board, offers a real time clock and full interrupt control. And the 16 port OMNIPORT™ offers you an efficient, economical board where more than 8 ports are needed.

With these and other quality products, Konan shows again that when it comes to S-lOO systems, it is definitely in control, (And all at attractive OEM and dealer prices.)

Call Konan's toll-free order line:

800-528-4563.

Or write ta Konan Corporation 1448 North 27th Avenue

Phoenix, AZ 85009 TWX/TELEX 9109511552

"Alpha Micro AM-500 is a trademark ol Alpha Micro Systems.

IN CONTROL, SMC-lOO. HARD TAPE. KNX-500, OCTOPORT. and OMNIPORT are trademarks ol Konan Corporalion.

Now-Break Through The 64K Micro-Memory Limit!

SIXTEEN

Bank Selectable 16K Static RAM

SAVE $50.09

LIMITED TIME OFFER

Don't buy any more antique RAMs (RAM without bank select) — now there's Netronic's new SWEET SIXTEEN board featuring a universal software bank select system. SWEET SIXTEEN is capable of addressing 2.048 different banks. With SWEET SIXTEEN boards you can add memory beyond the 64K limit, or expand to a multiterminal system. LOOK AT THESE FEATURES:

• 300 NS, low power 2114's.

• Software Bank Selector — Universal decoder works withCromenco. Alpha Micro. Netronics. most other systems, or your design. Onboard dip switches: Bank Select Enable: Reset Enable.- Reset Disable. Port Address.- Port Data.

• All Inputs And Outputs meet the proposed IEEE standards for the S-100 bus.

• 4.0 MHz Operation.

• Schmitt Trigger Buffer on all signals for maximum noise immunity.

• Addressable On 16k Boundaries, 0-64k. dip switch selectable.

• Phantom Option, dip switch selectable.

• PWR/MWRITE Option, dip switch selectable.

• LED Indicator to display status.

• Glass Epoxy PC Board with gold-plated contacts and double-sided solder mask.

• Fully Socketed.

• Four Separate Regulators for maximum stability.

10-Day Money-Back Policy For Wired & Tested Unit: Try a fully wired board — then either keep it. return it for kit. or simply return it in working condi

Continental U.S.A. Credit Card Buyers ■ ■■■■■■■■■■ Outside Connecticut: ■■■■■■■■■■■■

CALL TOLL FREE: 800-243-7428

From Conneclicut Or For Assistance: {203)354-9375 Please send the items checked below:

SWEET SIXTEEN kit; No. S-16 ... (reg. price S249.95) now S199.95* D SWEET SIXTEEN, fully assembled, tested, burned in; No. S-16W ... (reg. price $289.95) now S239.95* 'Plus $2 postage & insurance. Connecticut residents add sales tax. Total Enclosed: S

□ Personal Check □ Money Order/Cashier's Check

□ VISA P Master Charge (Bank No. I

Acct. No. Exp. Date

Signature

Print

Name

Address

City

Stale

-Zip

I5.NETR0INICS

RESEARCH & DEVELOPMENT, LTD.

333 Litchfield Rd., New Milford. CT 06776

62 February 1981 © BYTE Publications Inc

Listing 2: An example of the user interaction produced by the program of listing 1. The coded command-specification characters transmitted to the tank show up in this printout on the next-to-last line, because the same I/O-port address was used for both the remote-control transmitter and the printer interface.

COMPUTERIZED REMOTE CONTROL

Command list to be repeated each time (Y or N)? N COMMANDS :

(M)ove (F)ire

(C)lear (D)ump

(H)old (G)o

(R)epeat (D)ump (T)est

Command? M

(F)orward,(B)ackward,(L)eft,or (R)ight

? F

How many feet (1 to 99)? 2

Command Stored Command? H Hold how many seconds (total times .lsec)? 20

Command Stored Command? F How many shots (1 to 99)? 5

Command Stored Command? M

(F)orward,(B)ackward, (L)eft,or (R)ight ? I Turn how many degrees (0 to 360)? 90

Command Stored Command? M

(F)orward,(B)ackward,(L)eft,or (R)ight ? F How many feet (1 to 99)? 10

Command Stored Command? F How many shots (1 to 99)? 6

Command Stored Command? R Repeat how many steps? 2

Command Stored Command? G COMMAND CONTROL SEQUENCE IS BEING TRANSMITTED TO TANK

A!%l%SQ$25$!5SQTC%FTRANSMISSION COMPLETE Retransmit Same Control Sequence (Y or N) ?

Photo 11: When the electronic hardware has been built and is fully operational, the Big Irak Transport {a cargo trailer) provides a convenient method for dragging the wireless communication interface along.

Circle 36 on Inquiry card. —-#►

THE SOLUTION STORE

... Makes The Difference!

MicroAge Computer Stores sell solutions to your professional, business and household-management problems, not just hardware. That's what makes the MicroAge difference! From systems integration to easy-tounderstand application software, research and development to warranty service and repair, systems consulting to training and installation. In all these, we offer the latest, most innovative approaches. That's why we are the forerunners... the pioneers in the microcomputer industry.

But don't just take our word for it. Visit the MicroAge Computer Store nearest you and see the difference solutions make. We have differences you'll experience with every time and money-saving idea. The difference that will keep you satisfied now and for years to come!

ccvMPUTer sTore

"Where Vision Becomes Reality"

9530 Viscount El Paso, Texas (915) 591-3349

611 Rockville Pike Rockville, Maryland (301) 762-7585

5742 E. Broadway Tucson, Arizona (602) 790-8959

1707 Monroe Avenue Rochester, New York (716) 244-9000

1220 Melbourne Drive Hurst, Texas (817)284-3413

2065 El Camino Real West Mountain View, California (415) 964-7063

2525 N.Scottsdale Road Scottsdale, Arizona (602) 941-8794

83 South 10th Street 24 W. Camelback

Minneapolis, Minnesota Phoenix, Arizona (612) 338-1777 (602) 265-0065

1490 W. Spring Valley Road 4550-50 E. Cactus Richardson, Texas Phoenix, Arizona

(214) 234-5955 (602) 996-2910

2591 Hamilton Road Columbus, Ohio (614) 868-1550

Coming soon to: Denver, Colorado Milwaukee, Wisconsin Indianapolis, Indiana

FOR FRANCHISE OPPORTUNITY INFORMATION CALL (602) 967-1421

BANDPASS FILTER AND LI MITER

9V BATTERY

=_9V BATTERY

SERIAL DATA OUT ^—, 1/T f

TO FIGURE 3 <^—I °l I

Number

Type

+ 9V

-9V

GND

IC1

LM741

7

4

IC2

LM1458

8

4

1C3

XR2211

1

4

IC4

CD4011

14

7

Figure 7: The demodulator section of an originate-type modem. This is required at the receiving end of the computer/Big Trak link to decode the 2025 Hz and 2225 Hz tones received by the walkie-talkie. See photos 9 and 10 for views of the receiving system.

The XR2211 phase-locked loop is produced by Exar Integrated Systems, POB 62229, Sunnyvale CA 94086. Capacitors marked with an asterisk (*) should be the type made from Mylar.

Text continued from page 60:

ics community, but neither will it go unnoticed by those of us who like to play with toys. I hope you will recognize the independent capability of the wireless serial-communication link and use it in another application. As regards extensions of the control concept, a few more ideas came to mind while I was writing. The wireless communication method described in this interface is a one-way link, computer to remote peripheral device. However, the modem boards used in the prototype have fullduplex capability, even though only

half of each unit is used. Furthermore, within the tank-controller interface, I did not use the transmit portion of the UART.

If two more walkie-talkies operating on a different frequency are added, or if the two existing units are switched back and forth between send and receive, we could conceivably receive data sent back from the tank. The required interface components are presently available in the hardware (the other halves of the two full-duplex modem boards) but are not utilized.

What data might the tank send

back7 Do you remember that article I did a while back on the Polaroid Ultrasonic Ranging System? [In case you don't, see "Home In on the Range! An Ultrasonic Ranging System," BYTE, November 1980, page 32. ...RSS]

I'm sure you get the picture, but unfortunately I didn't have enough time to add that feature now. However, if you don't mind looking at Big Trak once more at a future time, I'd like to consider adding "eyes" and demonstrating control programs that exhibit more machine intelligence.

64 February 1981 © BYTE Publications Inc

Circle 37 on Inquiry card.

First compare quality. Then compare cost.

Morrow Designs' 10 megabyte hard disk system: $3,695.

MORE MEMORY. LESS MONEY.

Compare Morrow Designs' DISCUS M26™ hard disk systems to any system available forS-100 or Cromemco machines. First, compare features. Then, compare cost per megabyte. The M26 works out to under$200 a megabyte. And the M10 is about half the cost of competing systems.

COMPLETE SUBSYSTEMS

Both the M10 (8"), and the M26 (14"), are delivered complete with disk controller, cables, fan, power sup ply, cabinet and CP/M® operating system. It's your choice: 10 Mb 8" at $3,695 or26 Mb 14"at $4,995. That's single unit. Quantity prices are available.

BUILD TO FOUR DRIVES.

104 Megabytes with the M26. 40+ megabytes with the M10. Formatted. Additional drives: M26: $4,495. M10: $3,195. Quantity discounts available.

S-100, CROMEMCO AND NORTH STAR?

The M26 and M10 are sealed-media hard disk drives. Both S-100 controllers incorporate intelligence to supervise all data transfers through four I/O ports (command, 2 status and data). Transfers between drives and controllers are transparent to the CPU. The controller can also generate interrupts at the completion of each command ...materially increasing system throughput. Sectors are individually write-protectable for multiuse environments. North Star or Cromemco? Call Micro Mike's, Amarillo, TX, (806)372-3633 for the software ♦ "

package that allows the M26and M10to run on North Star DOS. MICAH of

Morrow Designs' 26 megabyte hard disk system: $4,995.

Sausalito, CA, (415) 332-4443, offers a CP/M expanded to full Cromemco CDOS compatibility.

AND NOW, MULT-I/O.™

Mult-I/Oisan I/O controller that allows multi-terminal and multi-purpose use of S-100 and Cromemco computers. Three serial and two parallel output ports. Real time clock. Fully programmable interrupt controller. Designed with daisy-wheel printers in mind. Price: $299 (kit), $349 assembled and tested.

MAKE HARD COMPARISONS.

You'll find that Morrow Designs' hard disk systems offer the best price/ performance ratios available for S-100, Cromemco and North Star computers. See the M26 and M10 hard disk subsystems at your computer dealer. Or, write Morrow Designs. Need information fast? Call us at (415) 524-2101.

Look to Morrow for answers.

MORROW OESIGN5

"CP/M is a trademark of Digital Research Corp. •Cromemco is a trademark of Cromemco. Inc. North Star is a trademark of North Star Computers, Inc.

5221 Central Avenue Richmond. CA 94804

n

Readers who wish to experiment with the wireless interface or want to build an inexpensive modem may order the following:

Blank printed-circuit board (shown in photos 7 and 10) and construction manual; can be built as either answer or originate full-duplex modem. Full details of the circuit on the board are described in "A Build-ItYourself Modem for Under $50," BYTE, August 1980, page 22, and construction manuals included in each board.

Single circuit board Two or more boards

$14 $12.50 each

Complete kit (printed-circuit board, components, and manual) necessary to build a full-duplex originate modem.

Complete kit

$39.95

Order these from:

The MicroMint Inc 917 Midway Woodmere NY 11598 (516) 374-6793

Please add $2 for shipping and handling. New York residents please add 7% sales tax.

MARK GORDON

COMPUTERS

DIVISION OF MARK GORDON ASSOCIATES. INC.

P.O. Box7 7,Charlestown, MA 02129 (617)4917505

COMPUTERS

Atari 800 W I 6I( 799.00

Level-ll I6K Sysiem 659.00

Model II G4K SyMem 3499.00

I 61< Model III 859.00

DISK DRIVES 40 Track 5'• Inch drive 314.00

80 Track 5'A 544.00

4 Disl. Drive Cable 39.00

PRINTERS

Centronics 730 599.00

EpsonMX80B .499.00

Centronics 737 849.00

OUidata Microline 83 1044.00

Integral Data 440C 999.00

NEC 5510 w tractor . . 2679.00

Oltidata Microline 80 599.00

Diablo 630 2495.00

MISC HARDWARE

Expansion int TRS 80IOIt) 249.00

Novation Cat modem 159.00

I OK Memory Kit 4 1.99

Leedex Monitor 109.00

Printer Cable for above 49.00

ISO-2 Isolator 54.00

AC LINE FILTER 24.00

STORAGE MEDIA

Verbatim box 10-5'j 25.00

Memorex box 10 5'a 22.00

Plastic Storage Box 5.00

OPERATING SYSTEMS

NEWDOS by APrARAT INC 49.00

NEWDOS+ by APPARAT INC 99.00

MMS FORTH DISKETTE PRIMER 79.95

NEWDOS 80 149.00

DISKETTE TRS-80* BUSINESS SOFTWARE BY SBSG

Free enhancements and upgrades 10 registered owners for ihecosi of media and mailing 30dayfree telephone sup port User reference on request Fully Interactive Accounting lockage. General Ledger.

Accounts Tayable. Accounts Receivable and Payroll

Report Generating

Complete Package (requires 3 or 4 drives) $475.00

Individual Modules (requires 2 or 3 drives) $125.00

Inventory II (requires 2 or 3 driven) $ 99.00

Mailing List Name &. Address II

(requires 2 drives) $129.00

Intelligent Terminal System ST 80 III $150.00

The Electric Tencil f rom MiCh.iel Shrayer $150.00

File Management Sysiem $ 49.00

FINE PRINT

TBS 80 is a Tandy Corporation uademark Useol aoove operating sys terns may require me use ol Radio Shach TRS DOS Radio Shack equipment surged to the will ana whim ol Radio Shack

ORDERING INFORMATION

We accept Visa ana Mastercharge We will Ship C 0 D ceriilieo check

or money oraeis only Massactiusetts residents add 5 percent sales tax

To order call toll-tree 1-8QO-343-5206

For inlormalion call 617-491 7505

Tha Company cannot bo liable lor pictorial or typographical i

Next Month:

Add a disk controller and 32 K-byte memory expansion to your TRS-80. m

Big Trak is a registered trademark of the Milton-Bradley Company.

Editor's Note: Steve often refers to previous Circuit Cellar articles as reference material for the articles he presents each month. These articles are available in reprint books from BYTE Books, 70 Main St, Peterborough NH 03458. Ciarcia's Circuit Cellar covers articles appeating in BYTE from September 1977 thru November 1978. Ciarcia's Circuit Cellar, Volume II presents articles from December 1978 thru June 1980.

BYTE's Bits

Johns Hopkins Contest on Applications for the Handicapped

Johns Hopkins University is sponsoring the First National Search for Applications of Personal Computing to Aid the Handicapped. The contest is being funded jointly by the National Science Foundation and Radio Shack.

The contest addresses the full spectrum of physical and mental handicaps, including: learning disabilities, visual handicaps, hearing, language, neuromuscular or neurological disorders, and limitations of movement. There are three separate categories of competition—student, amateur, and professional—with both cash and equipment prizes awarded in each category. Contestants must be residents of the United States. Categories of submission include: prototypes, computer programs, and system concepts/ ideas. Individual rights remain with the contestant.

We applaud all parties concerned for conducting this worthy effort.

The deadline for submissions is June 30, 1981. For a descriptive flyer and further information, write to:

Personal Computing to Aid the

Handicapped

Johns Hopkins University

POB 670

Laurel MD 20810B

66 February 1961 © BYTE Publications Inc

Circle 38 on inquiry card.

Circle 39 on inquiry card.

Software Packages

Evergreen Data Systems

Evergreen Tax Package US1040 Tax return

package wilh selected state schedules S1000 Computerized Accounting & Tax Service Taxman* US 1040 tax return preparation. Con

handle 29 schedules S3000

CMC Legal Billing* Allows attorney to monitor charges

based on hourly rates, costs, or (lot lees.

All AR lunctions S2500

Computer Management Systems General Ledger & Payroll* Single diskette based,

easy to use program Writes checks, W-2's and

914s. Ideal tor small retailer. S500

Tek-Aids Industries, Inc. 0S65U (ig-FORTH Hard disk mulli-user, chains with

basic programs, requires OS-65U S250

(ig-FORTH Stand-alone version ot the FORTH

Interest Group Model S175

BUS-I Original version, with GL, AR, AP 6 diskettes

wilh new docs. S99

BUS/DMS* Most current version ot BUS series.

Special Si 50 discount tor PO 's submitted with

original copies ot Digital

Technology BUS-II SB50

MEMTEST/2Neweditionolpopular memory testtor

OSI hardware. 8" and 5" disk S50

DCS Software Products WP/INT* Interface between WP-2 and any DMS file

lor form letters S80

Tra-Sta Amway Distributors Package Order entry/inventory

Package lor direct Amway buyer Maintains

commission structure S995

BBS Data Director* Powerful data base manager.

Command oriented, very interactive S995

Tri-Comp System Exerciser Sell-prompting test routines for

end user troubleshooting. S60

Farragher and Assoc.

Med-Bill Single doctor client billing S995

Frisch Computer Systems Manufacturing Control System* Hard disk based

Standalone inventory with job costing and

bill-of-materials Extensively field tested S3500 DQFLS

DQ Mail* DMS interface for WP6502 form letters Version 12 S75 DQ Justify right-hand copy justification and

incremenlal spacing program VI 2 S50

WP6502 OS65U Version of popular word

processor. Versionl.2 S100 Version! 3 S250 (JCSD System Users Society USUS Software Exchange Library 6 diskette set of

UCSD Pascal programs, USUS membership S80 Abacus Data Systems Mailer* Text processor plus key file/sort capability.

Good moss moiler. S190

Payroll* Thorough package for floppy or hard disk

End User Maintenance Service recomm. S495 General Ledger* Profit center support, journal

based, (loppy or hard disk. S495

Digital Technology BUS-II Manufacturer's original version SI50

*DMS Compatible

Affiliated Dealers

Creative Office Systems Indianapolis, Ind. 4624 I

Small Business Systems, Inc. Gering, NE 6934 1

Kansas Computer Liberal, KS 67901

Custom Systems Development Wichita, KS 67214

BIP Murphysboro, IL 62966

Abacus Data Systems Greensburg, PA 15601

Business Computer of Joliet Cresthill, IL 60435

Business Data Systems, Inc. Bouldei; CO80301

Case Computer Bradley, IL 60915

Computer Management Systems Mitchell. SD 57301

CSB Houston, TX 77057

Cybertronics Houston, TX 77084

Data Buss Grayslake, IL 60038

Data Services Computer Corp. Denver, CO 80239

Delta Data Distributors Memphis. TN 38118

Farragher & Assoc. Milwaukee, Wl 53213

Frisch Computer St Paul, M N 55113

International Automation New Kensinglon. PA 15608

KMH Galesburg, IL 61401

MAP Systems Peoria His , IL 61614

Specialized Computer Systems Jackson, MI 49204

Taxman Salt Lake City, UT84115

Tek-Aids Industries, Inc. Arlington Hts , IL 60004

Tra-Sta Computer Shoppe Pueblo, CO 81005

TriComp Inc. Denver, CO 802 21

Total Data Systems Fl. Collins, CO 80525

Whitlock International, Inc. Detroit, Ml 48219

WINS

The Ohio Scientific Software Game

Selecting software for your Ohio Scientific computer is a chancy task at best. There are few trustworthy vendors with a national reputation. There are no consistent quality standards and the documentation is often cryptic and inaccurate. If you are lucky enough to find a good package, there's no guarantee of ongoing support. A wrong choice results in months of wasted time, effort, and money.

With the Software Federation, you no longer take that risk. The Software Federation was formed by three of the largest Ohio Scientific hardware distributors to select and market quality software through reputable dealers nationwide.

DEALERS

The Software Federation soloes the dealer's problems by prodding tow cost access to high quality software with the sort of demonstration packages, documentation, and support that the dealer needs to successfully sell machines.

AUTHORS

The Software Federation soloes the independent oendor's problems

by prooiding a proprietary method of software protection, aggressioe enforcement of software licenses, a strong dealer base, primary support, and national adoertising.

END USERS

The Software Federation soloes the user's problems by prooiding quality software, exceptional documentation, after-the-sale support, and optional software maintenance seroices.

Why risk making the wrong choice? With the Software Federation, eoeryone wins! See the dealer in your area for a complete turnkey demonstration.

Software Federation Inc.

44 University Drive Arlington Hts,, IL 60004 Phone: 312/259-1355

A Beginner's Guide to Spectral Analysis

Part 1: Tiny Timesharing Music

Mark Zimmermann

9410 Woodland Dr

Silver Spring MD 20910

We live in two worlds that co-exist in space and time; they touch each other and interpenetrate at every point and at every moment. In fact, each world contains the other within it.

One is a world of forms, of colors, of sounds; the other is a world of complex numbers, of mathematical functions. Most people aren't aware of this second world, but that doesn't make it any less valid as an expression of reality. It's not hard to peek into this "alternate universe": this article and the accompanying programs will attempt to aid you in doing so. If a student devotes some time to the concepts suggested here, he'll find himself rewarded with a set of extraordinarily useful tools. Some facts which aren't obvious in one world are obvious in the other; some tasks which are slow, laborious, and expensive in the first world become quick and cheap in the second.

My description may sound a bit like Oriental mysticism, but it's not! This article will try to sketch an introduction to Fourier analysis, one of the most powerful developments in modern mathematics. It will emphasize the feel of the subject, not the complicated algebraic formalisms. No advanced mathematical training is required, but it may help to have access to a small computer for some parts of the discussion. The programs that I've written for illustrative purposes are in either BASIC or 6502 assembly language, and were specifically designed for the 8 K-byte Commodore PET. It should be a fairly straightforward process to adapt these programs to comparable machines.

The first part of this article will introduce the one-dimensional Fourier transform, and emphasize its importance to music and human perception of sound. Included is a "tiny timesharing" program that is both educational and enjoyable. It generates simple musical themes using the building blocks of intervals, and varies these themes via a series of inversions. New musical elements are introduced pseudo-randomly, so the patterns never repeat, and the tone quality is also constantly varied. All of this uses only about 0.1% (yes,

The "tiny timesharing"

program generates

simple musical themes

using only 0.1 %of the

computer's time.

one-tenth of one percent!) of the computer's time, which allows other programs to be run simultaneously with no noticeable loss of speed.

In the second part of this article, I will outline the simple extension of a one-dimensional problem into a twodimensional plane. The program that illustrates this process uses pictures drawn on the PET's video-display screen and transforms them by a process similar to that of making a hologram with coherent light.

The references at the end of each part should be useful for anyone who wants more information on the topics encountered. You may also find it helpful to consult your neighborhood Fourier guru, who has probably chosen to be reincarnated as an elec

trical engineer or radio astronomer.

The Frequency Domain

The central idea of Fourier (or spectral) analysis is quite simple. One of the best ways to understand it is to think about a musical chord, produced by simultaneously hitting several keys on a piano. Suppose you play a chord and want to record it— how can you do that7

One way to preserve a chord for posterity would be to record it on a tape deck or (if you collect antiques) on a gramophone wax cylinder. In either case, the method of recording is essentially the same: the sound impulses are translated into magnetic field patterns, or into the wiggles of a groove, and stored just as your ear/ microphone perceives them. If you had an oscilloscope, you could display the sound on a screen and photograph it.

But there's also a completely different way to save the chord. You can draw a musical scale and write down the notes that are hit. This scale doesn't show the moment-by-moment variations of air pressure against your eardrums; instead, it relates something about the frequency of these pressure waves, and the set of frequencies that is being created by the vibrating piano strings.

A recording method that stores a sound as a function of time is said to work in the time domain. A method that breaks a sound up into its constituent frequencies and records the amount of each frequency component that went into the original sound is said to work in the frequency domain.

The usual musical notation for

68 February 1981 © BYTE Publications Inc

TO ORDER CALL (212) 687-5000

H Ul M

SUPEWRAIM"

INTE3TEC DATA SY5TEMS 64K

ONLY

$2995

32K $2795

More than an intelligent terminal, the SuperBrain outperforms many other systems costing three to live times as much. Endowed with a hefty amount ol available software (BASIC. FORTRAN, COBOL), the SuperBrain is ready to take on your toughest assignment. You name it! General Ledger, Accounts Receivable. Payroll, Inventory or Word Processing.. .the SuperBrain handles all of them with ease. FEATURES INCLUDE:

• 2 dual-density miniffoppies with 360K bytes of disk storage • A CP/M Disk Operating System with a high-powered text editor, assembler and debugger

Model QD

7ZQK Bytes disk storage and 54K RAM

S3895

SUPER BRAIN HARD DISKS

10 Megabyte

16 Fixed-16

Removable

$4495 $9995

APPLE II PLUSforPr/ce

A complete self-contained computer system with APPLESOFT floating point BASIC in ROM, full ASC 11 keyboard in a light weight molded carrying case.

Features Include:

• auto-start ROM • Hi-Res graphics and 15 color video output

• Expandable to 48K.

Supertalker $279 Micromodem $379

Disk 645 Superterm (24 x BO) 395

Add-on Disk 495 Speechlab 229

Pascal Card 495 Communication Card ... . 225

Business Software 625 Modem 200

Monitor 159 Graphics Printer 595

Printer Card 180 Graphics Tablet 795

[apple//

IS FINALLY HERE 128K RAM!!

NEW96K

80 Column

Commodore CBM

Basic 4.0 Operating System

• 80 column by 25 line display

• 12" CRT

• New screen editor

• Split screen processing

• Super fast string handling

• 15 additional basic commands

• Supports relative record processing

Model 8032

32K memory

$1795

NEW! Model 8096

96K memory

Call for price I

NEW 8050 DUAL DISK SI795

1 million bytes on-line storage

and DOS 2.0 operating system

NEW 2031 SINGLE DISK $595

Commodore Computer

These low cost Commodore PET Business Computers have virtually unlimited business capabilities. Accounts Receivable, Inventory Records, Payroll, and i other accounting i :-*s:-.s^'*p.

functions. / |

PET16N&32N/ sMIi

COMPUTERS I

• Full size keyboard

• 16 or 32,000 Bytes Memory

• Level III Operating System

• Full Screen ~ Editor,

• Upper lowercase& 64 graphic characters PET DUAL FLOPPY DISK

• Stores 360,000 Bytes on-line

• Microprocessor ■^—■* controlled

'• — • Uses single or

dual sided floppies HI-SPEED PRINTER • 150 cnaracters per secorid • Up to 4 copies 8" wide -j • Microprocessor Controlled • Prints All Graphics • Full Formatting Capability

l

PRINTERS,

CENTRONICS SALE

YOUR CHOICE

779-2 or 737-3

ONLY

$895

CENTRONICS 704

180 cps Bi-Directtonal • Up lol5" gaper Width . 9 x 9 Matrix • Upper/Lower Case

• Tractor Feed

• RS-232 Serial Interface

$1795

CENTRONICS 700-9

$1 295 List $1895

■ 60 cps • Up to 15" paper width • Tractor Feed ■ Parallel Interface for Apple & TRS-80 ■ 2 channel vertical forms! • Top of Form!

VR-300 S1795

(25cps Letter Quality)

EPSON MX-80 S 645

Paper Tiger 445 795

Paper Tiger 460 1295

MONITORS

SANYO 12" GREEN $325

BMC 12" GREEN 295

SANYO 13" COLOR 495

ZENITH 13" COLOR 395

LEEDEX 12" B&W 159

CENTRONICS 737 Parallel $895

Serial

ANDERSONJAC0BS0N

841 I/O Terminal Ideal for -ord processing and mall businesses. S 1 230

ASCII Code 15 CPS Printout High Quality Selectric Printing Reliable heavy duty mechanism Completely Refurbished by A.J.^ • Delivered FREE to nearest service center'

CLOSE OUT SPECIALS!

Ljit Special

Chatsviorth Card Reader for TRS-80 750 450

| Axiom 801 495 195

[ Protollne PET to Centronics Interface .... 199 49

Microsomes PET/Ham Interface 125 49

Exidy Sorcerer BK ,095 349

TEXAS instrument. 39/4 $635 OveT 1000 SOftV/Bte

(with 13" color Monitor) . _, . . ' .. . .

tao&s, books, disks,

Centronix 779-2 5895 inf#wv», wvno, """'"!

on display. Come in and browse.

XEROX 1730

Letter Quality

Special $2495

List $2755

" 40 CpS

• Uses all 100 metal & plastic daisy wheel.

■ Automatic bidirectional printing

■ Fewer moving parts go Day On Site Warranty

DEALER INQUIRIES INVITED ON XEROX. CENTRONICS. SUPERBRAIN

XYMEC HQ 1000

with 10, 12; 15 Pitch & Proportional Spacing

1 Z-80 controlled <fcO/lQC > Up to 198 columns JpfctWO

V/SA*

BUB

Min.Credit Card Order $75

NY residents add 3°'o sales tax

• Same day shipment on prepaid and

credit card orders

TO ORDER CALL (212) 687-5000 h.JKHichim.ii-.

The COMPUTER FACTORY """'"^^ri™"8''LoM,>

notes on a scale doesn't give enough information to completely reconstruct the original chord. Even if each piano key produces a pure tone with no harmonics or distortions, you should still specify more than which keys were punched. You must say precisely how loud each note in the chord was played and the precise time that each note began (ie: the amplitude and the phase of each pure note in the chord). Given that amount of data, the original sound can be reproduced exactly. The frequency-domain method of recording then contains as much information as the conventional time-domain recording technique.

That's really all there is to Fourier analysis. There are, of course, precise mathematical formulas for translation from the time to the frequency domain, and back. There are also modern improvements on these formulas, such as the fast Fourier transform, which can do the same job in much less time than the old-fashioned method. But the basic ideas remain the same: the Fourier transform is a technique for changing notation from one way to another in order to

record the same information.

There are many references (see references at the end of this article) that explain the mathematics of the Fourier transform. I'd like to avoid these, and try instead to explain the meaning of the transform, and the uses to which it can be put.

Why Transform?

I have already mentioned the application of Fourier analysis to music, and I'll return to this topic later. There are numerous other uses for the transform concept. Almost any wave-like phenomenon can show interesting behavior when looked at in the frequency domain. Light, when spread into a spectrum, reveals information about the source that produced it: that's how astronomers determine the composition of distant stars. (The word "spectrum" is the source of the term "spectral analysis.") Radio signals, grouped at different frequencies, carry hundreds or thousands of simultaneous telephone calls, TV broadcasts, etc. A receiver simply performs a partial Fourier analysis in order to separate one-program from the crowd. Ocean

FINDING SOLUTIONS

AND BEING COMPETITIVE

IS OUR BUSINESS.

Having problems and looking for a

computer to help solve them?

Are you finding computer dealers

come in one of two ways? Either

Full system support with Full price

or Take it or Leave it with Low

price. At Omega we don't believe

that you should have to make a

choice. Yes, we're in business to sell

products but also, to solve your

problems. Our prices will be the

lowest possible. Our support and

product quality will be second to none. Check out our Mail Order prices in this

ad (our retail prices will be higher). See if you don't agree with our first claim.

For our second claim, call us with your data processing needs and problems.

Better yet, come in and see us. Finding solutions and being competitive is our

business. We never forget either of them.

-tJ.

tipple computer

* Authorized Dealer

APPLE II "PLUS" 16K 48K

S 929.95 1079.95

Apple II Accessories:

Disk II with Controller & 3.3 DOS $535.00

Disk II 2nd drive 435.00

Graphics Tablet 665 00

Language System with PASCAL 395.00

Silentype Printer w/lnt 489.00

Integer Firmware Card 152.00

Z-80 Softcard 259.00

Videx Videoterm 80 col Card 279.00

Sanyo 12" Green Monitor 279 00

Calculators: (S2.00 shipping charge) Hewlet Packard

HP-85 CALL

HP-67 $299.00

HP-34C 127.00

Texas Instruments

TI-58C 109.00

Cannon

P10-D 80.00

Sharp

6200 98.00

5100 89.00

HP-41C $269.00

HP-97 589.00

HP-38C 127.00

TI-59 209.00

P7-D 80.00

5813 35.00

5102 80.00

Mail Order Terms ot Sale: Price based on prepaid orders. Visa or Master Charge orders may have service charge added to purchase price. No COD'S Allow 14 working days tor personal and company checks to clear. All orders (unless specified in ad) within Continental U. S. shipped U.P S. no charge. APO or out of Continental U. S. write or call for snipping charges. All prices subject to change and all offers subject to withdrawl without notice. CA residents add 6%

OMEGA MIGflC QOMPIITEFS

The Problem Solving Company 3447 Torrance Boulevard • Torrance, California 90503 • (213) 370-9456

waves can be resolved into frequency components, each traveling with its own speed. This approach helps, for example, in understanding how tsunamis (tidal waves) are created by undersea earthquakes and travel thousands of miles across the water before cresting on a shore.

Fourier analysis is also applicable to things that aren't functions of time. In calculating the heat distribution within a nuclear reactor core, one useful method involves breaking up the spatial dependence of the temperature into pieces that vary with different spatial frequencies. Similar techniques work to explain the shape of a soap film over a bent wire loop, the electrical field patterns inside a microwave cavity resonator, or the air density and pressure variations inside an organ pipe. (In the latter two cases, time dependences also exist as a part of the problem; the time dependences can be easily solved once the spatial Fourier analysis problem is understood.)

In recent years, myriad practical applications of spectral analysis have been developed, particularly in electrical engineering. If a signal is first transformed into the frequency domain, it often becomes easy to filter out noise and interference. On the other hand, by scrambling frequency components you can make a voice incomprehensible (unless the scrambling pattern is known) and allow relatively secure communications over a channel that is not secure. Quite often, it's most efficient to manipulate a signal by transforming it into the frequency domain, working it over, and then transforming back; the cost of transforming is more than repaid by the speed and convenience of many operations when applied to the frequency components of a function.

In the field of computing, Fourier analysis concepts have proved to be extremely helpful. The invention of faster algorithms as an aid in multiplying large numbers got its start from fast Fourier transform theorems. The spectral test for random number generators, one of the most powerful tests known for detecting non-random biases, is a Fourier technique. Even before electronic computers existed, mechanical "calculating engines" were built to do Fourier analysis because of the importance of the subject.

70 February 1981 © BYT1 Publications Inc

Circle 40 on Inquiry card.

Circle 41 on inquiry card.

cs or mnvim

HCrC'S Cfedt Whether you're just s!;irtintc out

«»,«—«> fSr 'n electronics or moving up froni an

"CiVS IOr analog VOM to ;i digital nuilrimeter,

eleCtrOfllCS voy'll Ix* Kmart to make sure thai

enthusiasts on y"u''y miim. ym[ monTs ■v,,nh

f ^ — j II I \ I Mil .1U1II II I'M (| IH

Small DUOgetS. performance I )MM. Ik- sun

consider the new I) SIM) fro:

NOW VOU Can [Viced at only $125* this dc

fake home six-function handheld I)M.\

«■» vt lr wwjfKM available now ;ii select eleei

a t lUKe UJMJM supplv stores throughout th for $125t" 'i'111'' \ KM offers 0.,Vr

available now ;it select electronics supplv stores throughout the I'.S.

the I) SIX) offers (1,7r basic dr accuracy (live limes better than analog voltmeters), a razor-sharp .''>': digit LCD readout, unsurpassed overload protection, and true, one-hand operation.

I his hardworking basic measurement multimeter is designed from the inside nut for long life and reliability. All 1) 800specifications are traceable to the National Bureau of Standards.

As part of Fluke's new Series I) line of low-cost digital multimeters, the I) SIX) carries a limited one-year parts and labor warranty and conies complete with the battery, and safety-designed lest leads.

Ask your supplier about the I) MX), then compare it fcature-forIcalure with any other low-cost DMM. You'll find that for only $125J there's never been more multimeter than the new I) SIX) from Fluke.

From the world leader in DMM s Now we've designed one for you.

•Suggested U.S. list price

odoes. 1-800-42(5-9182

FLUKE

10 DAY FREE RETURN

NEC THE FIRST NAME IN LETTER QUALITY PRINTERS.

CompuMart otlers beautiful print quality with NEC Spinwriter terminals Both KSR and RO versions give unsurpassed hard copy output. CALL

ANNADEX

132 Col. Printer High quantity at a super price. Dot Matrix, serial parallel 8c current loop standard. ISO c.p,s. Bi-Direction. S1650.

CENTRONICS PRINTERS

The incredible Model 737. The closest thing to letter quality print tor under Sl.OOO. 737-1 (Parallel Interlace) - S899.

NEW FROM INTEGRAL DATA THE IDS 445 PRINTER

Priced lower than the 440 and equipped with a better print head. Advanced technology strikes!

IDS 445 w/Graphics Capabilities S894.

IDS 445 w/o Graphics Capabilities S795.

NEWI IDS 560 132 Column Graphics Printer S1695. TheIDS460 S1295. Features include; Correspondence quality printing, highresolution graphics capability, programmable print justification.

Omni Printers bom Texas Instruments

The 810 - Lfat S1895. SALE! S1795. The 820 (Ro) Package — Includes machine-mounted paper tray and cable. A compressed print option and device forms control are standard features. $2,155.

The 820 (KSR) Package Includes lull ASCII Keyboard plus all of the features on the RO S2395.

APPLE

We carry the most complete inventory of Apple computers, peripherals, and software. CALL! Can Best Selling Apple System. Save over S250 on our most popular Apple System. System includes a 48K Apple U. Apple Disk. D053.3,8< Controller, and a Sup R. Mod RF Modulator, list: S2070.

CompuMait Sale Price: $1795.

COMMODORE

CompuMart has delivered more Commodore computers in the US. than any other dealer. Call us now for low prices and special deals. NEW FOR PET, Visicalc (Need 32K 8c a disk drive) $199. Word Pro L $29.95 - Word Pro 2, $99.95 - Word Pro 3, $199.95 Word Pro 4, $299.95.

NEW bom Apple foi the Apple 11

Dos 3.3 Convert disks to 16 sector format lor 23% more storage and faster access $60.

SOFTWARE FROM APPLE Apple Plot. The perfect graphic complement for Visicalc. $70 Dow Jones News 8c Quoles $95 Adventure (Uses 48K) $35

DOS Tool Kit $75

Apple Fortran $200

Tax Planner $120

FROM PERSONAL soltware Visicalc $149

Desk Top Plan $99

NEW FROM MUSE The Voice $39.95

Super Text $99.00

Address Book $49.95

Miscellaneous Apple II AccessoiieS:

Easy Writer (80 coL need a Videx) $249

Easy Mover $49

Easy Mailer $69

HARDWARE ACCESSORIES FOR APPLE

Silentype Printer w/x face $595. Super Sound Generator (mono) $159 (stereo) $259

light Pen $249

X-IO Controller (plugs into paddle port) $49

Dysan Diskettes — Single side.

Single density, Hard or Soft Sector

$5. ea.

Memoiex 3401's — 51A discs

$3.25 with hub ring for Apple

$3.50.

Memoiy IntegratedCircuits —

Call lor qty. discounts when ordering over SO units. Motorola 4116 (200 Nanosecond Plastic) $4.50 ea. Faiichild 2114(Standard Power. Plastic) $4.50 ea.

COMPUMART stocks the complete line of MATROX PRODUCTS.

Call lor specs.

COMPUMART now offers the ENTIRE DEC LSI-11 PRODUCT LINE Call lor prices 8c delivery.

NOVATION CATto ACOUSTIC MODEM

Answer Originate, 300 Baud Bell

108. Low Profile Desiga $179.00

NEW! D-CAT

Direct Coupler from Novation

$199.

EXIDY SUPER SALE

We want to clean out our inventory of Exidy computers To do this we've priced our Exidy equipment so low you'll have to call us for prices.

New liom VIDEX! — Video Term. SO Col. x 24 line, 7x9 Matrix plug in compatible board for the Apple n. Price $325 without graphics EPROM With graphics EPROM $350.

S.S.M. Serial 8c Parallel Apple Interface $225

ABTs Numeric Key Plan $110 California Microcomputer Keyboard ..a^ass^ $195

Mountain Computei — Expansion accessories for your Apple Introl - lO System $289

Super Talker $299

The Music System $545

ROM plus board w/Keyboard filter $199

Clock Calendar $280

16 Channel A to D Converter $350

Apple Expansion Chassis $650 ROM Writer $175

NEW bom Lear Sieglei!

We have the following Lear Siegler Terminals in stock at prices too low to print — Call lor quotes.

ADM — 3A Industries favorite dumb terminal lor some very smart reasons. ADM — 3A + NEW from Lear Siegler. CALL! IT S HERE! - It is the new Intermediate Terminal from Lear Siegler. Call for details.

Limited Time Ober, Oux Hazeltine prices slashed again!

Haezltine 1410

List 3850 Compumart $749 Hazeltine 1420 List $995 CompuMart $825 Hazeltine 15CO List $1095 CompuMart $965 Hazeltine 1510

List $1395 CompuMart $1135 Hazeltine 1520 List $1585 CompuMart $1199 Hazeltine 1552 list $1395 CompuMart $1235

Compumart's exclusive ATARI SPECIALS

ATARI 8CO Personal Computer System — Comes with 8CO operators Manual. 16K Rany Memory module, IOk ROM Operating System, Power Supply, TV Switch Box $950.

EXCLUSIVE bom CompuMart! Special Ofier. Zenith Coloi Video Monitor tor $379!

NEW FROM SANYO - Four Great Monitors at Low CompuMart Prices. Sanyo's new line of CRT data display monitors are designed for the display of alphanumeric or graphic data.

9" Sanyo Monitor $169.

12" Sanyo Monitor $289.

12" Sanyo Monitor with green

screen $299.

13" Sanyo Color Display Monitor

$495.

SEND FOR OUR FREE CATALOG

<

HP-41C Calculator $288.00

Memory Modules: For storing programs or up to 2,000 linesof program memory . $45.00,-'-;-. "Extra Smart" Card Reader. Records programs and data back onto blank magcards . $199.' The Printer. Upper and Lower case, High resolution plotting, Portable Thermal

operation $355.00

Application Modules ... $45.00

NEWI The PMC-80, The new

computer that's software compatible with the TRS-8Q Level 11 16K at $645.

ACCESSORIES FOR PMC - 80 EXP-lOO S-lOO Bus Expander Disk. Printer, RS232 I/O $410.

S-32K S-lOO Bus 32K RAM Board for EXP-lOO $295.

CAB-40 Cable 12" long ribbon

cable

lor EXP-lOO. -- t $25.

PERIPHERALS

Atari 410 Program Recorder (FREE w/purchase of Atari 8CO) $89.95

Atari 810 Disk Drive ($100 off with purchase)

$699.95 NEW Dual Disk double density

$1499.95 825 Printer (Centronics 737)

$995.00 RS232 Interface w/Cable $249.95 NEW! light Pens $74.95 NEWI Visicale for Atari ATARI'

$199.00

A

IMPORTANT ORDERING INFORMATION All orders must include 4% shipping and handling. Mass. residents add 5% sales tax. Michigan residents 4% lor sales tax. Phones open irom 8;30 a.m. to 7:00 p.m.. Mon-Fri: 11:00 a.m. to 4:00 p.m. Sat. RO.'s accepted lrom Dun & Bradstreet rated companies-shipment contingent upon receipt of

signed purchase order. Sale prices valid lor month ol magazine date only-all prices subject to change without notice. Our Ann Arbor retail store is open 11:00 am. to 7:00 p.m. Tues.-Fri.. 10:00 a.m. to 5:00 p.m. Saturdays. Stop by and visit.

CompuMart's Microllex 65 System lor your AIM Includes: Adapter Buffer Module w/4-slot module stack. 8K RAM module, 16K PROM/ROM module, Asynchronous communications Interface, and Power Supply $1,29 Call 01 writer for our complete Microllex 65 brochure

HP-S5

Hewlett-Packard's Personal Computer lor Industry, This extremely portable computer features extended BASIC to solve your problems quickly and efficiently along with an advanced graphics system to enhance communication. HP-S5 ACCESSORIES We carry H.P. Peripherals (Disk Drives to Graphics Plotters) Enhancements (BASIC Training, General Statistics, Financial Decision Math. Linear Programming $95 ea).- HP-85 Accessories. (Enhancement ROMs, ROM

ROCKWELL AIM 65

Our AIM system includes 4K AIM with BASIC interpreter assembler. Power Supply, Cassette recorder & Enclosure $79 .

4K ATM-65 $499.

PL65 High Level Language $125. Paper lor the AIM (roll) $2.50

Rockwell's 4-slot Motherboard (sale) $175.

drawer. Overhead Transparency Kit), Supplies (Plotter Pens, Tape Cartridges),- Interface Modules (HP-IB Interface, HP-IB Interconnect Cables, Serial (RS-232C) Interface Module). We can get your every HP peripheral made for the HP-85. CALL FOR COMPLETE DETAILS 8c SPECS.

The HP-85

Quality, Versatility, Portability

CompuMart has been serving the computer needs of industry since 1971.

We stock, for immediate shipment, only those products from the finest micro-computer manufacturers.

And any product, except software, can be returned within lO days for a full refund — even if you just change your mind.

We also honor all manufacturers' warranties. Our expert technicians will service any product we sell that cannot be better, or faster, serviced by the manufacturer's local service center.

Call us for more information on products, product configuration and service. Our phones are open Monday thru Friday, 8:30 a.m.to 700 p.m. and Saturday HOO a.m. to 400 p.m.

We have a staff of highly knowledgeable sales people waiting to hear from you, and to help.

Because service is what we're all about.

800-343-5504

In Mass. Call 617-491-2700

SYSTEMS

iCOMPUMART

65 BENT STREET, DEPT. 000, RQ BOX 568 CAMBRIDGE, MA 02139

Circle 42 on inquiry card.

Listing 1: RMS Spectrum Plot for the Commodore PET. This program calculates and displays on the screen the Fourier components produced by a given bit pattern in the PET's shift register. The data is "played" with some extra hardware, as detailed in figure 1.

1 REM N-BIT POWER SPECTRUM ANALYZER, COPYRIGHT 1979 MARK ZIMMERMANN

10 INPUT "NUMBER OF BITS"; NB: INPUT "HIGHEST HARMONIC"; HH

30 NM = NB -1: DIM S(NM), C(NM), F(NM), TS(NM,NM), TC(NM.NM)

40 FOR I = 0TONM: X = 2*t*I/NB: S(I) = SIN(X)/ir: C(I) = COS(X)/?r: NEXT I

50 INPUT "NOTE (1 TO 255)"; NT: POKE 59467,16: POKE 59464,NT

60 FOR 1 = 0 TO NM: FOR J = 0 TO NM: X = I*J: Y = X+I: X = X-NB*INT(X/NB):

Y = Y-NB*INT(Y/NB)

70 TS(I,J) = S(Y) - S(X): TC(I,J) = C(X) - C(Y): NEXT J: NEXT I

80 REM SET UP MATRICES TO ALLOW SPEEDY INTEGRATIONS LATER

100 INPUT "TONE QUALITY"; D: IF D<256 THEN POKE 59466,D

110 DD = D: REM MAKE BINARY REPRESENTATION OF D IN LINE 120

120 FOR I = NM TO 0 STEP - 1: F(I) = DD-2*INT(DD/2): DD = INT(DD/2): NEXT I

130 PRINT "[cls]";D;" = ";: FOR 1 = 0 TO NM: PRINT F(I);: NEXT I: PRINT

150 FORK = l TOHH: X = K-NB*INT(K/NB): C=0:S = 0

160 FOR J = 0 TO NM: C = C + TS(X,J)*F(J): S = S + TC(X,J)*F(J): NEXT J

170 C=C/K: S = S/K: A = SQR(C*C + S*S)

180 PRINT "[home]";: FOR I = 1 TO 0 STEP - 0.05: IF A >I THEN PRINT TAB(3*K); " ♦ ";

190 PRINT: NEXT I

200 NEXT K: FOR 1 = 1 TO HH: PRINT TAB(3*I-1);I;: IF I>8 THEN PRINT "[cl]";

210 NEXT I: PRINT

220 GOTO 100

100K

GND |—s.

(PIN N ) I ?~

15/iF

-H(—o

.0.01/tF

TO AMPLIFIER

-o

m

SPEAKER

2.2 K CB2 [ ^> VIAr

2N2222

Figure 1: Circuits to adapt the PET to a common audio amplifier (top), or to produce an audio output directly (bottom).

Music and the Fourier Transform

Unlike the other senses, the ear seems to work naturally in the frequency domain. Physiologically this may result from the structure of the cochlea in the inner ear; sounds of different frequencies stimulate different spatially separated areas (so that the motion of the eardrum is Fourier transformed!). It is both interesting and educational to experiment with sounds of various frequency spectra. A microcomputer can be a great aid to this kind of experimentation, since it can reliably generate

precise, easily modified waveforms, as well as perform the mathematical work required to calculate the spectrum of any particular wave. Both the pitch and the tone quality are variable.

The program RMS Spectrum Plot (see listing 1) was designed for just this kind of experiment. The mathematical parts can be run on any computer that understands BASIC; on the PET, the spectrum is graphically plotted on the video display, but a numerical output would be an acceptable alternative. This program also

makes use of the recirculating shiftregister in the MOS Technology 6522 VIA (Versatile Interface Adapter) integrated circuit in the PET. The VIA has an output to pin CB2 of the PET's port edge connector. Any trivial amplification circuit (see figure 1) can be used to amplify and isolate this output to give an audible tone. Many other microcomputers have similar tone-generation capabilities; otherwise, a separate waveform generator may be used to study the sounds that are being Fourier analyzed.

RMS Spectrum Plot performs a straightforward N-bit power-spectrum analysis. For use on the PET and most other microcomputers N = 8 is the case of interest, but there is no harm in making a more general program and allowing for an arbitrary N. (Note that for N not equal to 8, the tones produced by the PET's shift register are not the same as the tones being analyzed by the program. Also note that for N greater than 16, PET BASIC w ill not correctly handle the array look-up operations for arrays TS and TC, which would need to have more than 256 elements.) I won't go into the mathematical operations that are being performed in the course of the spectral analysis: some of the references cited later do that in great detail. Instead, 111 try to explain the results, the physics and the physiology that the program helps explore.

Earlier I mentioned that in order to describe a sound completely in the frequency domain, you must provide more than just the list of frequencies that went into the original sound. A complete specification also requires the amplitude of each frequency component and its phase. By phase, I mean a measure of where a sinusoidal signal is in its cycle of 0° to 360° at some moment of time. (For example, the functions sin(f) and cos(f) look very similar, but one is 90° out-ofphase with the other.) Two sounds with the same set of component frequencies and the same amplitude can look completely different when displayed on an oscilloscope, and they make completely different wiggles in a phonograph groove (see figure 2).

So, phase information is crucial for the accurate reconstruction of the original sound. High-fidelity amplifier and speaker advertising emphasize this—you must spend lavishly in order to get really good, precise sound reproduction. Or must

74 February 1981 © BYTE Publications Inc

Circle 43 on Inquiry card.

For those special people who've stepped ahead with a mini-computer

maxej

Mini-FW

■BBAmnhShB

maxell

Mini-Floppy Disk

Maxell offers a way to stay ahead.

A Maxell 5Va" Mini-Disk will consistently let you maximize the capability of your system today. And as your involvement with it grows, tomorrow as well. Maxell Mini-Disks are ail made with the same exacting 100% certification and critical dependability of the Maxell 8" Floppy Disk. So you know your 5Va" Maxell Mini-Disks meet or exceed the same ISO and Shugart specifications industry requires.

There are double density Maxell single and doublesided 51/4" Mini-Disks for soft and hard sector systems. And 8" Maxell Floppy Disks for every disk drive configuration. See your computer supply dealer or write to us for more information. If you are a computer products dealer, write for the growing opportunities Maxell Business Products Division offers you with our 8" Floppy and 5Va" Mini-Disks.

maxell

BUSINESS PRODUCTS DIVISION

Maxell Corporation of America, Business Products Division, 60 Oxford Drive, Moonachie, N.J. 07074 Tel: 201-440-8020

1111

f(t) = sin(t) + — sin(3t) + — sin(5t) + — sin(7t) + — sin(9t) 3 5 7 9

1111

f(t) = sin(t) + — sin(3t) sin(5t) + —C0S(7t) sin(9t)

3 5 7 9

Figure 2: Different sounds that are composed of the same frequencies. These waveshapes are made up of the same component frequencies, but with a variation in phase between them.

you7 The program in listing 1 allows you to see the difference that phase information makes in perceived tone quality. In my experiments, I've found it to make no difference whatsoever. This agrees with most of the unbiased technical references I've read on the subject. The human ear is a marvelous Fourier analyzer as far as separating sounds into their component frequencies, but the ear seems to throw away almost all data about the phase of the sounds. (Perhaps some phase information helps to determine whether sounds are coming from the left, right, or in front of a listener, but that too is unclear.)

Even without phase information, sounds of the same fundamental frequency produced by RMS Spectrum Plot can reveal an interesting variety of textures as their bit patterns are changed. The program allows the user to set the shift register shift rate by choosing the value of the variable NT, between 1 and 255. The fundamental frequency of the output is then determined by the simple formula:

frequency = (62,500 Hz)/(NT +2)

For example, NT = 140 closely approximates the standard frequency of 440 Hz, the note A above middle C.

Once the frequency of the note is chosen, RMS Spectrum Plot allows you to hear what an arbitrary bit pattern (waveform) sounds like, while the machine does a spectral analysis of the pattern and displays the results. These notes are composed of a fundamental frequency component, called /, plus varying amounts of sound energy at frequencies 2f, 3f, 4f,...—the harmonics of the fundamental tone. After line 170 is executed, for each frequency KXf, the variables C and S contain the amount of the Kth harmonic of the signal which looks like a cosine (in C) or like a sine (in S). A = SQR(CXC + SxS) is the amplitude of the Kth harmonic (the thing that the ear is sensitive to); it is this amplitude A which is plotted on the screen (see photos la, lb and lc for examples).

The best thing to do now is to stop reading and to experiment a bit with

<APPLE WORLD

3-D ANIMATED COLOR GRAPHICS Written in machine code. The program made famous on national T.V.I by Paul Lutus

APPLE WORLD turns your Apple into a sophisticated graphics system capable of creating animated three-dimensional color images, protecting them in true perspective on the screen, rotate them, move them closer, furtheraway, and many other exciting and imaginative things.

Draws objects with 65,000 points per side.

A powerful screen-oriented text editor is included to facilitate image fomation. This program was recently featured on Tom Snyder's Prtme Time Saturday TV Show and is now available for sale.

APPLE WORLD'S powerful editor is so easy to use that children wilt love it. Youcan now "sketctV'your dream house, boat, car, or fantasy empire. Then view it as it would be seen from 10.000 feet, or you can ZOOM in until the screen is filled with a doorknob. You could then go inside and move from room to room examining furniture placement as your screen rotates within the room. Images or specific parts of images can easily be saved to disk or printer.

Does all this sound like science fiction?

Youwontthinksoafteryou have visited Apple World.

INTRODUCTORY PRICE $59.95

36 page manual included

For 48K Apple II or Plus with Disk

3-D

SUPERGRAPHICS

& 3-D GAME DEVELOPMENT SYSTEM IN COLOR ' ny Paul Lutus

Watch colorful butterflys. birds, fly across your Apple or Atari screen with true3dimensional perspective. Have rocket ships fly out at you in this incredible high speed graphics package. 3-D SUPERGRAPHICS" is a 6502 machine language program that will interface to your Basic or machine language programs or games using simple ■'DOS-like" commands.

Fealuras include:

• Simple image entry through editor

• Objects up to 256 points per side

• Uses all hi-res colors

• Allows mixed colored text & graphics for promots and captions

• Translates on 3 axes

• Individual axis scales

• 21 different commands

• Rotate object 1.4° to 360° increments at machine speeds

FOR 48K APPLE II OR PLUS WITH DISK II $39.95 FOR DISK

FOR ATARI 800 WITH 40K MEMORY (DISK OPTIONAL)

' $39.95 FOR TAPE

OTHER SOFTWARE

APPLE COMPUTERS

Super Space Wars S 9.95

States & Capitals 9.95

Moving Point

Average 19.95

Stock Options 24.95

Finance 12.95

Bonds 12.95

COMMODORE PET

Slock Options 24.95

Finance 12.95

Bonds 12.95

Stock Analyzer 22.95

Mortgage 14.95

Space Intruders ("Best

Game of 1979").. 19.95

Jury/Hostage 9.95

Kentucky Derby/

Roulette 9.95

Alien I.G./Tank 9.95

Tunnelvision/Maze

Chase 14.95

Submarine Attack 9.95

Battle of Midway 7.95

Laser Tank Battle 9.95

Swarm 14.95

Baseball 9.95

Super Startrek 14.95

PET Music Box 29.95

76 February 1981 © BYTE Publications Inc

ATTENTION APPLE & PET OWNERS

MARCH 10,1981

will mark the beginning of a new era in Microcomputer Software. A Relational Database Management System and an Intelligent Accounting System will then be available for Apple and PET users.

Request Thinker

Relational Query System for Management

• Most powerful database scheme known

• First TRUE relational database management system (ALL records are cross-indexed to ALL other records!)

• Multikeyed random access (No sorts ever)

• Sophisticated screen formatting & data entry (Like on IBM 3270!)

• Full report writer

• Extensive search capabilities

• Automatic data compression for increased disk capacity

• Records up to 4K in length

• Interfaces to Visicalc", The Source'", and word processors

• Much more!

Accounting^ Software that thinks for itself.

EASY TO USE—

Fully Integrated Accounting System

The THINKER'" consists of 7 comprehensive interactive modules, with all transactions applied immediately and the results are instantaneously accessible. They are:

• ACCOUNTS RECEIVABLE • ACCOUNTS PAYABLE • SALES ORDER ENTRY . PURCHASE ORDER ENTRY • INVENTORY CONTROL • GENERAL LEDGER • MAILING LIST

FLEXIBILITY—

Software That Grows With Your Business

The THINKER" utilizes the D YNAF1LE'" Multi-Keyed Fil Allocation Scheme which dynamically manages file length and records to meet the businessman's needs and will automatically extend itself to work on hard disks without any program modification. No disk space is wasted because the system automatically recaptures space when records aredeleted. DYNAFILE'" utilizes a sophisticated indexing scheme, allowing direct access to any record- Machine language programming insures DYNAFILE*" speed, reliability, and integrity

SUPER KRAM

Now With Multi-Key Capabilities For Apple & Pet

by Ken Gerrnann

Since KRAM™ was introduced in 1979 it has fast become known as the quickest and most powerful access method for serious Apple and Pet users. Now, after hundreds of requests we have added MULTI-KEY, MULTI-INDEX, functions, as well as increasing processing speed.

IBM/370 users have VSAM (Virtual Storage Access Method} to provide fast, flexible keyed-access to their data. Now SUPER KRAM (Keyed Random Access Method), from United Software of America, gives Apple and Pet users the same flexibility, substantially increasing the processing power of the Apple and Pet.

Until SUPER KRAM the only "random access" capability in the Apple and Pet consisted of a crude form of "relative record" processing. While this is usable for very simple applications, it (alls far short of the needs of today's business and analytical applications. Using SUPER KRAM records may be processed by any one of multiple "Key" values, which may consist of any kind of data: numbers, letters, special characters, etc. Even Apples's longawaited DOS 3.3 doesn't have anything like this!!

KRAM™ 2,0 Only $99.95 SUPER KRAM™ Only $175

KRAM™ 2.0 Regular Features

• Written in 6502 machine code Basic compatible

• Create/Open a dataset

• Put record by key

• Add & delete records by key

■ Get any record by Full/Partial key

• Access by any key in as littie as .2 sec. {.1 sec. with Corvus disk)

• Supports multipledisks

• Read next or previous record

• Dynamic space allocation

• Dynamic space reclamation

• Dynamic index compression

■ Files never need reorganization

■ Compatible with language systems

SUPER KRAM'S™ Added Features

• MULTIKEY SUPPORT — Allowing simultaneous access to a KRAM file by more than one key field.

• HI-SPEED READ—This feature allows increased I/O speed up to 60% faster during processing of SUPER KRAM read next, read previous, put and delete requests.

• IMPROVED INDEX ARCHITECTURE — Allowing faster index searchers and more efficient disk space utilization.

• INTEGRATED BASIC COMMANDS — Allowing SUPER KRAM" commands to be coded in-line with Basic, providing easier usage ol KRAM than ever before.

• USER-SPECIFIABLE BUFFER POOL — Allowing the user to specify how many KRAM files are allowed open at one time; will support any number of KRAM files.

• LOGICAL RECORDS (KEYS MAY BE NON-UNIQUE)— Records added to the KRAM f iies are immediately accessible by any of the defined keys for the file (Automatic Upgrade).

• KRAM 2.0 files are totally compatible with SUPER KRAM

750 3RD Avenue,

New York NY 10017

(212) 682-0347 Telex 640055

UNITED SOFTWARE OF AMERICA

Look for the RED-WHITE-BLUE United Software Display at your local computer dealer, or send check or moneyorder, plus $3.00 shipping to:

DEALER INQUIRIES INVITED

KRAM is a trade mark of United Software of America.

Photo 1: Sample runs of RMS Spectrum Plot, analysis of the sound.

The program "plays" an arbitrary bit pattern while displaying a power-spectral

the program. Try to discover which bit patterns are indistinguishable to the ear; see which ones you like best. (My favorite is 00101101, which has no even harmonics and sounds rather like a clarinet.)

Distinctive Voices

The bit patterns that produce distinct frequency spectra are the basic building blocks for generating shift-register-type music. You can certainly find all seventeen different 8-bit voices by trial and error or long and tedious searching, but such an approach becomes much more difficult as the number of bits increases. In any case, there is a better way to find the set of interesting bit patterns: use a computer! The program Music Generator (listing 2) uses a technique that is simple, yet interesting, and applicable to many other problems.

In setting up the problem of finding all distinct voices, the first thing is to determine how two bit patterns can be "equivalent." (This is involved with the mathematical concept of a group, and is actually a good introduction to that subject.) First, it is obvious that patterns like 00000001 and 00001000 and 10000000 are all equivalent since they look the same (a single 1 and seven 0s) once they've started cycling around in the shift register. Similarly, 00101101 and 10100101 are equivalent: the second pattern results from applying five rotate-left operations to the first. We can call the operation which takes the leftmost bit of a bit pattern and moves it to the right end ROL for rotate-left. Any patterns which can be converted into each other by a series of ROL operations are equivalent.

But there are other ways in which two bit patterns can be equivalent. Consider the patterns 11111101 and 00000010. If you graph these patterns, you can see that the waveforms to which they correspond are exactly the same, except for a shift of the zero-voltage level and a change of polarity. The power spectra of these patterns are also the same, except for the zero-frequency component which the ear can't hear and which isn't plotted by RMS Spectrum Plot. (The zero-frequency component is just the average of the bits, eg: V8 for the pat

tern 11111101.) Since these patterns are the same as far as the ear is concerned, they should also be called equivalent. In binary arithmetic, the relation between these patterns is that each is the l's complement of the other: all Is are changed to 0s, and vice versa. Since the l's complement of a binary number / is just 11111111-/ (if / has 8 bits), it's easy to program in BASIC. We can call this operation INV for inverse, and add it to the list of operations that transform bit patterns into other, equivalent patterns.

Listing 2: Music Generator for the PET. When used to generate music waveforms, this program will produce audibly distinct tones based on 8-bit patterns in the PET's shift register. Qualities are constantly modified through the application of symmetry operations (inversion, rotation, etc) to produce interesting variations.

10 REM BIT PATTERN GENERATOR (C) 1979 MARK ZIMMERMANN

20 DIM V%(7): REM ARRAY FOR BIT PATTERN DISPLAY

100 FOR I = 1 TO 127 STEP 2: REM TRY ALL POSSIBILITIES THAT DO NOT OBVIOUSLY FAIL

200 Z = I: FOR K = 1 TO 7: GOSUB 5000: REM ROTATE BITS OF Z LEFT

220 IF Z<I GOTO 1000: REM REDUCED TO A PREVIOUS CASE IF Z<I

240 NEXT K: REM PASSED FIRST TEST IF REACH HERE

300 X = 255 -1: REM INVERT BIT PATTERN (1 's COMPLEMENT)—X > I SINCE LOOP WAS 1 TO 127

320 Z = X: FOR K= 1 TO 7: GOSUB 5000: REM ROTATE BITS

340 IF Z<I GOTO 1000: REM REDUCED TO PREVIOUS CASE...

360 NEXT K: REM IF HERE, PASSED SECOND TEST

400 GOSUB 6000: REM REVERSE BIT ORDER OF I, RESULT RETURNED IN X

500 IF X<I GOTO 1000: REM FAILED AGAIN

600 Z = X: FOR K = l TO 7: GOSUB 5000: IFZ<IGOTO 1000

620 NEXTK

660 Z = 255-X: FOR K= 1 TO 7: GOSUB 5000: IF Z<I GOTO 1000

680 NEXT K: REM IF HERE, A SUCCESS!!!!!

800 X = I: FOR K = 0 TO 7: V%(K) = X-2*INT(X/2): X = INT(X/2): NEXT K: REM GENERATE BITS

900 PRINT I;TAB(10);: FOR K = 7 TO 0 STEP - 1: PRINT V%(K);: NEXT K: PRINT

1000 NEXT I

2000 GOTO 9999

5000 REM ROTATE BITS OF Z LEFT

5020 Z = 2*Z: IF Z>255 THEN Z = Z-255

5040 RETURN

6000 Y = I: X = 0:FORK = 0TO 7: X = 2*X: IF Y< >2*INT(Y/2) THEN X = X+1

6020 Y = INT(Y/2): NEXT K: RETURN: REM RETURN WITH X THE REVERSED VERSION OF

I

9999 END

78 February 1981 © BYTE Publications Inc

In this age of runaway inflation...

Look what $795* will buy

The ideal input device for the small system user.

5S Si

j;;;;-; «ww sj*m *j*

«iim 170.00 «i»-j m.D0

»!»'• «££

TV) HX ^|

"»' ll>»

»,...■■ ■b» .-t

Wx.ll Ml

m

s-i" is:

Available with stylus or optional cursor.

The HIP AD™ digitizer

Inexpensive input to your computer

The HIPAD™ digitizer can be used for both converting graphic information into digital values and as a menu. Utilizing either the stylus or the optional cursor, the operator can input graphic data into the computer by locating individual points on the digtizers 11" x 11" (28cm x 28cm) active area. In the "stream mode" a continuance of placements of coordinate pairs may be input.

Not a kit, the HIPAD™ comes complete with both RS-232C and parallel interfaces and has its own built-in power source. The origin is completely relocatable so coordinates may be positive or negative for a true reference value and oversized material may be input by simply resetting the origin.

Accurate positional information, free form sketches, even keyboard simulation

All can be entered using the multi-faceted HIPAD™ digitizer. Its capabilities and low price make the UL listed HIPAD™ a natural selection over keyboard entry, inaccurate joysticks, or expensive approximating light pens. It's perfect for inputting isometric drawings, schematics, X-rays, architectural drawings, business graphs, and many other forms of graphic information, as well as creating your own graphics.

Use it with Apple II™ , TRS-80 Level II ™, PET™ or other popular computers

The HIPAD's™ built-in RS-232C and parallel 8 bit interfaces make it all possible. (For Apple II order DT-11A, forTRS-80 or PET order DT-11). Furthermore, you get English or metric scaling, data format (Binary/BCD/ASCII), selectable baud rates, and resolution of either .005" or .01".

For complete information contact Houston Instrument, One Houston Square, Austin, Texas 78753. (512)837-2820. For rush literature requests, outside Texas call toll free 1-800-531-5205. For technical information ask for operator #5. In Europe contact Houston Instrument, Rochesterlaan 6, 8240 Gistel, Belgium. Telephone 059127-74-45.

Available with optional display. "U.S. Suggested retail price

TM HIPAD is a trademark of Houston Instrument TRS-80 is a trademark ot Tandy Corporation APPLE is a trademark of Apple Computer Inc. PET is a trademark of Commodore Business Machines, Inc.

Circle 44 for literature

Circle 45 to have representative call

houston instrument

GRAPHICS DIVISION OF

BAUSCHSLOMB ▼

I've only been able to think of one more symmetry operation to apply to bit patterns. (If you find others that leave the voice that the ear hears unchanged, please let me know.) This final operation is to reverse the bit order. For example, reversal changes 11010000 into 00001011. Physically, reversal corresponds to playing a bit pattern backwards, or to reversing the flow of time. I abbreviate this operation REV.

Now there are three symmetry operations: ROL, INV, and REV. Applying any one of them to any bit pattern leaves the sound that the ear hears unchanged. By repeatedly

applying these operations, it's easy to discover sets of bit patterns that change into each other (the patterns 00110011, 01100110, 10011001, and 11001100 make up one such set).

How does this theoretical knowledge help you to determine which bit patterns are distinctive voices and which are redundant among the 256 possibilities? A crude way would be to apply various combinations of ROL, INV, and REV to a candidate pattern, and consider it new if it is never transformed into an alreadyknown or old pattern. A slightly better method would be to systematically apply a series of the symmetry

DISPOSABLE HEAD. UNBEATABLE PRICE.

INDUSTRIAL MICRO STOWS, the industrialstrength microcomputers priced like the lightweights. All IMS systems feature a Z80 4 mHz CPU, 5-100 bus with 10 (series 5000) or 12 (series 8000) slot motherboard, DMA (IBM-compatible) double-density floppy disk controller, 32K high speed (250 nS) static RAM, rugged power supply, two RS232 serial ports and one parallel port (all expandable). Each IMS system comes in your choice of an attractive desk-top or rackmount enclosure. CP/M is included. SERIES 5000 wftfi 5 1/4" drives With 1wo single-sided, double-density drives $2531.20 With two double-sided, double density drives 2908.75 SKIES 8000 with 8" drives With one single-sided, double-densily drive $3359.00 With two single-sided, double-density drives 4029.00 With one double-sided, double-density drive 3659.00 With two double-sided, double-density drives 4549.00

EPSON MX-80 Dot Matrix Printer

The world's first tfcpovr+le print head. When it wears out, just throw it away. A new one costs less than S30, yet it's so simple, you can change it with one hand.

features: Bidirectional printing, logic seeking, 80 cos with up to 105 LPM throughput in 10 cps mode, adjustable tractor pin type feed.

UST S645 00

MX-80 Serial Version ... . $562.50

MX-80 Parallel Version $562.50

MX-80 Serial Version $599.00

MX-80 IEEE488 . . $599.00

Apple Cable .$ 21.90

TRS80 Expansion Cable $ 30.65

HIGH SPIED IMS S 100 MEMORY BOARDS

16K 250 nS static RAM 290.00

1

1

CP M is a tracJemark of Qqital Research

I 32K 250 nS static RAM 585.00 64K Dynamic RAM 937.50

60% FEWER WORKING PARTS.

WORDSTAR 2.1 The List Microhouse

premier word-processing

software by MicroPro 495.00 349.98

WORDSTAR 2.1 with

MtdMetge 645.00 489.98

DATASTAR data entry, retrieval, ond update

system from MicroPro 350.00 279.98 SUPERSORT sort/ merge/extract software gives your CP/M micro the power of a key-to-disk system 250.00 199.98

MORE RELIABLE. LOWER PRICED.

Trie NEW

NEC Spinwriter

3500Q

UST S2000 00

| NEC Spinwriter 3500Q Parallel . . . $1742.50 Horizontal Tractor Feed . $ 144.00

Vertical Tractor Feed $ 180.00

Cut Sheet Feeder $1080.00

TCS/Atiarrta Accounting System:

General

Ledger compare at 530,00 175.00 Accounts 1 Receivable compare at 530.00 175.00

Accounts

Payable compare at 530.00 175.00

Payroll compare at 530.00 175.00

1

MASTER CARD OR VISA WELCOM

PRICES AND SPECIFICATIONS SUBJECT TC

CHANGE WITHOUT NOTICE

CALL OR WRITE FOR FREE CATALOC

» » • 1

All four packages 595.00

Microhouse

Sample printouts (all 4 pkgs

included) 10.00

Manuals (one pkg per manual) Each 35.00

80

511 North New Street Bethlehem. PA 18018 (215)868 8219

February 1981 © BYTE Publications Inc

Circle 46 on Inquiry card.

operations that would guarantee that no possible transformations were missed. For example, it's clear that you need never apply more than seven consecutive ROL operations to a pattern, since the eighth application brings you back to the original pattern. It's also clear that applying INV (or REV) twice in a row makes no sense, since it just flips the bits back again. There are many possible sequences of operations that will find all possible transformations of a pattern. One simple sequence is: ROL seven times, INV, ROL seven times, REV, ROL seven times, INV, and ROL seven times. After each operation, a potentially new equivalent bit pattern is produced. Applying the sequence to the pattern 00001011 will generate all thirty-one other equivalent patterns, with no repetition; applying it to a pattern like 01010101, which has only one equivalent (10101010), will, of course, produce many repetitions.

The program of listing 2 essentially goes through this process in order to find the set of seventeen distinct voices, but with a few refinements to speed it up. First, the program works exclusively with the decimal number corresponding to each bit pattern, not with the pattern itself. This allows the program to use simple BASIC arithmetic operations to perform ROL, INV, and REV. Only when a number is discovered to be a new voice is it converted into a bit pattern for display. Second, no time is wasted in checking even numbers, or numbers greater than 127. Every even number corresponds to a bit pattern ending in a 0, and a single rotation right (or seven rotations left) will always produce a pattern corresponding to a smaller binary number. Any number greater than 127 can always be reduced to a number less than 127 by an INV operation. Third, Music Generator doesn't bother storing a list of already-discovered old patterns with which to compare the result of each transformation. Instead, it uses a neat yet trivial mathematical trick, one that should be part of every alert programmer's repertoire. Let me introduce it to you with a short story:

An engineer, a physicist, and a mathematician are taking an intelligence test. Each is led, separately, into a room containing a table and a stove. On the table there is a pitcher of water, a kettle, and box of tea.

Circle 47 on inquiry card. *

u

i

Memory—you never seem to have quite enough of it.

But if you're one of the thousands of Apple owners using the SoftCard, there's an economical new way to expand your memory dramatically.

16K ON A PLUG-IN CARD.

Microsoft's new RAMCard simply plugs into your Apple II,® and adds 16k bytes of dependable, buffered read/write storage.

Together with the SoftCard, ■ the RAMCard gives you a 56k CP/M® system that's big enough to take on all kinds of chores that would never fit before (until now, the only way to get this much memory was to have an Apple Language Card installed).

GREAT SOFTWARE: YOURS, OURS, OR THEIRS.

With the RAMCard and SoftCard, you can tackle largescale business and scientific computing with our COBOL and FORTRAN languages. Or greatly increase the capability of CP/M

, , F H

->■ t j r j ►

w

' 1 Bj hL J| J ■

k! M -1 i|J

»Oe./i©2i—.

H-,

)

applications like the Peachtree Software accounting systems. VisiCalc™ and other Apple software packages can take advantage of RAMCard too.

And RAMCard gives you the extra capacity to develop advanced programs of your own, using the SoftCard and CP/M. Even with the RAMCard in place, you can still access your ROM BASIC and monitor routines.

C JOIN THE SOFTCARD

FAMILY.

The RAMCard is just the latest addition to the SoftCard family — a comprehensive system of hardware and software that can make your Apple more versatile and powerful than you ever imagined.

Your Microsoft dealer has all the exciting details. Visit him soon, and discover a great idea that keeps getting better.

Microsoft Consumer Products, 400108th Ave. N.E., Suite 200, Bellevue, WA 98004. ^Ie!- (206)454-1315.

CPU's &

SUPPORT

CHIPS

RAM'S

- 5.95

- 12.95

- 13.95

2.90 2.75

- 6.95

BOSSA

AMD 29 8105

8212 8216

62*6

3228

8251

B259

8257IAM9517) - 8.95

Z80A SIA - 17.95

8275 - 16.95

FOI79I - 34.95

UART's

AYS-1013 - 3.75

1602E - 3.95

AV3-8500 -1.9S

PT1482B -3.25

2114L-3

4116-3

41162

21102-3

2102-4

MK4027-3

MK4096-11

TMS4045-25

MS4050NL

2101-1

2107BI52B0

MMS270

MK40089

40D1

- ■

4002 4006

_ ".

3.95 3.75

4008 4009 4010

- s

6.75 .99

4012 4013

.90 3.50 2.95

4014 401S 4D16

6.50 3.95 2.45

1.75

401B 4019 4020 4021

3.45 1.95

4023 4024 4025

'

80 4034 - 2.25 .-15 4035 - 31

4W2

4044

4046

.37 4050

- .45 4053

4515

4516

4518

4520

74C00

74C02

;

74C74 - , 74C76 - . 74CB3 - 1 74CB5 - 1 74C86 74C90 74C93 74C151 - 1 74C1S7 - 1 74C160 „ 1. 74C161 - 1 74C163 - 1 74C165 - 1 74C173 - 1

_ .40 74C17

74CK1 74C14 74C20 74C12 74C73 ■

F4C175

.27 74C926 - 6,95

ROM's

2708

- 6.95

NTERFACE

2716

- 12.95

& DRIVERS

2516 2532

- 15.95

- 29.95

6223

- 3.95

.«S - 1.40

82573

- 2.95

1489 - 1,25

82S112

- 7.95

8130 - 2.50

82S123

- 4.95

8131 _ 2 50

62S126

- 2.95

82S129

- 3.25

8833 - 2.50

82S130

- 3.45

B2S131

- 3.95

8837 - 2.00

- 6 95

8T380 - 2.00

SPECIAL VALUE

8" SOFT SECTOR DISCS

Made by Magnetic Periferals

with documentation

115V AC, +5VDCat1A, +24VDCatlA,

-5/-12V DC at .3A

Single sided, single density

144,000 bytes of data after formating

14 lbs. shipping weight

Used in good condition

Shugart and IBM format compatible

*25000

SPECIALS GOOD THRU FEBRUARY 1981

*m 'i r -n^Mi—La

TRANSISTOR SPECIALS

2N1303PNPGETO 5 . .

2N1307PNPGETOS .

2N404APNPGETO5. . .... 3/91,00

HEPG6014- PNPGETO 3 . S .85

TIP 121 - NPN Si SWITCHING 5 .95

2N6233-NPN SWITCHING POWER . SI.95

MRF80Q4 aCBRf TRANS'STOR NPN S .75

2N3772 NPN S.T03... S1.00

2N4908PNPSiTO-3 .... $1.00

2N5086PNPSiTO92 ..4IS1.00

2N3137 NPN Si RF .. $ .55

2N3919 NPN Si TO 3RF $1.50

2N1420NPN SiTOS . ,31*1.00

2N3767NPN Si TO 66 $ .70

2N2222 NPN Si T 0.18 .... ... S/S1.00

2N2907 NPNSiTO IB 4/S1.00

2N3055 NPNSiTO 3 .. .$ .60

2N3904NPNSiTO92. 6191.00

2N3906 PNPSiTO.92 G'Sl.OO

2N5296 NPN Si TO 220... $ .55

2N6109PNPS.T0-220. ..$ .55

TIP31BNPNS.T0 220 $.60

TIP32B PNP S. TO 220 S .65

TIP34PNPSi .$ .95

TTL IC SERIES

7400

7401

7402

7403

7404

7405 7i06 7407

7408

7409

7410

7411

7412

7413

7414

7416

7417 7420

7425

7426

7427 ■7430

7432 7437

7433

7440

7441

7442 7445 7446 7447 7448

7450

7472

7473

7474

7475

7476 7480 74B374B5

7490

7491 74927493

7494

7495 749674107 74121 — 7412274123

74125

74126 74145 74150- 1 74151 74153 75154 - 1 74155 - . 74157 - , 74160 - .

74161

74162 - '

74163

74164

74165

74166

74167 74170- '

74173

74174

74175

74176

74177

74180

74181

74190

74191

74192

74193

74194

74195

74196

74197 74279 74325 74365

74367

74368 74360 75325

75491

75492 8T98

DATE1/S DACOBaC 8bitDAC - $9.95

8" DISKETTES HARD SECTOR $1.75,10/$16.00

74500 74S02

74S04 74S05 74S08

74S11 74S15 74S20

74S30 74S32 74S86 74SB9 74S112 74S133 74S140 74S153

.40 74S151

.40 74S157

.60 74S15B

1.90 74S174

.85 74S257

1.40 74S25B

1.00 74S374

1.10

7 WATT LD 65 LASER DIODE IR $8.95

25 wan Intra Red Pulse (SG 2006 equiv.) Laser Diode (Specsheetincludedl s?.

2N3820 P FET $ .45

2N5457NFET $ .45

2N2646UJT $ .45

ER 900 TRIGGER DIODES.. .. . 4/$1.00 2N 602B PROG. UJT $ .65

ttlheedrelay - SPST5V20ma $1.00

CLOCK CHIPS

MM53B7AA $5.95

MM5314 $4.75

MM5316 $4.95

CRYSTALS $3.45 ea.

6.144MH2

8.000MHz 10.000 MHz 18.000 MHz 18,432 MHz 20.000 MHz

RIBBON CABLE

FLAT (COLOR CODED)

#30 WIRE

IScond. -.40/perioot 40cond. - .75/perfooi 50cond. - .90/perfoot

MINIATURE MULTI-TURN TRIM POTS 100. 5K, 10K.20K. 2&0K, ... $.75ea>

NO. 30 WIRE WRAP WIRE SINGLE STRAND

100' $1.40

ALCO MINIATURE TOGGLE SWITCHES

MTA 106 SPOT $1-05

MTA206 DPDT 91.70

MTA206P-DPDTCENTROFf $1.85

MSO 206 P-OPOT CENTEROFF LEVER SWITCH, S1.B5

FULL WAVE BRIDGE

PRV

2A

6A

25A

100

1.40

200

.80

1.30

2.20

400

1.00

1.65

3.30

600

1.30

1.90

4.40

SCR's

600

1.5A | 6A 35A |110A

3.60

15.00

TRIAC's

DIP SOCKETS

8 PIN .17 22 PIN .30

14 PIN .20 24 PIN .35

16 PIN .22 28 PIN .40

18 PIN .25 40 PIN .60

74LS SERIES

PRV

1A

10A

25A

100

.45

.80

1.55

?00

,R4

1.30

2.10

400

1.30

1 90

3.10

600

2.00

2.75

4.30

FP 100 PHOTOTRANS $ .50

RED, YELLOW OR GEEN LARGE LEDs. .2' 6/$ 1.00

RED/GREEN BIPOLAR LED's $ .55

MLED92 R LED S .75

MRD14B PHOTO DAHl.XTOR $ .75

TIL-118 OPTO-1SOLATOR * -75

IL-5 OPTOISOLATOR $ .80

1 WATT ZENERS; 3.3. 4.7, 5.1, 5,6, 6.8, 8.2, 9.1,10, 12,15,18, or22V 6/S1.00

SFC 3301 - 50 PRV 30A FAST RECOVERY DIODE (35ns) ..$2.25

SILICON POWER RECTIFIERS

74LS - .22

74LS01 - .22

74LS02 - .22

74LS03 - 22

74LS04 - .27

74LS0& - .27

74LS08 - .27

74LS1I - JS

74LS13 - £0

74LS14 - .80

74LS15 - ,35

74LS20 - .30

74LS13

70

TANTALUM CAPACITORS

10UF10V - $ .40 22UF10V -$ .30 15UF16V 3/$1.00 30UF6V 5/S1.00 33UF20V $ .60 100UF15V $ .70 150UF15V $ .95

4LS21 74IS22 74LS26 74LS27 74LSJ.B 74LS30 74LS32 74LS37 74LS3B

74LS51 74LS54 74LS73

.22UF35V 5/S1.00 .47UF35V 5/S1.00 .68UF35V 5/S1.00 1UF35V 5/$ 1.00 2.2UF20V 5 $1.00 3.3UF20V 4/$1.00 4.7UF 15 V 5/S1.00 6.8UF35V 3/$1.00

SANKEN

AUDIO POWER AMPS

Si 1010 G 10 WATTS .. $ 7.50 Si 1020 G 20 WATTS .. $13.75 Si 1050 G 50 WATTS .. $26.90

200 PRV 1A LASCR .95

RS232 CONNECTORS

DB25Pmale $3.25

DB25Sfemale ... $4.25 HOODS $1.50

PRV

1A

3A

12A

50A

125A

240A

100

.06

.14

.35

.90

.3.70

500

200

.07

.20

.40

1.30

4.25

6.50

400

.09

.25

.65

1.50

6.50

9.60

600

.11

.30

.60

2.00

8.50

12.50

800

.15

.35

1.00

2.50

10.50

16.50

1000

.20

.45

1.26

3.00

12.50

20.00

IN4148IIN914) . 15/S1.00

.1 or .01 uf 25V ceramic disc. capis.16/$1.00, 100/S5.00

REGULATORS

74LS75

7C.

74LS76

.4h

74LSB3

4S

74LSB5

II)

74LSB6

4S

74LS90

11)

74LS92

HI)

74LS93.

u.1

47

74LS112

.4h

74LS113

4S

74LS1U

ss

74LS123

'h

74LS125

<.)

74LS126

Ml)

74LS132

HI)

74LS136

.HI)

74LS13B

,7 b

74LS151 -V 74LS153-1.19 74LS1S5-1.19 74LS156-1.19 74LS157- .as 74LS160-100 74LS161- 1,00 -4LS162-1.00 74LS163-100 74LS164 - 1 00 -4LS16B-125 74LS169-1.75 74LS170-1.70 74LS173- .90 74LSW4- 100 74LS175-1 00 74LS1B1 -2.50 74LS190 -1.25 74LS191-1.15 74LSI92- 90 74LS193- SO 74LS19 5- 90 74LS196- 1.00 74LS197- .90 74LS240-1.60 74LS241- 1 60 74LS242 - 1 60 74LS243- 1 60 74LS244- I.B0 74LS245-2 25 74LS251- 1.29 74LS253 - 1.00 74LS257- 90 74LS25B- .90 74LS259 -1.50 74LS266- .70 74LS273- 1 25 74IS279- .70 74LS2M - B0 74LS293- ,B0 74LS365- .80 74LS366 - 80 74IS367- 80 74LS3 8- 80 74LS373- 1.50 74LS3.5- .95 74LS377 - 1.50 74LS386 - 50 74LS393 - 1.50

LM3T7T $1.75

LM337 $2.50

323K-5V3A $5 75

79HGKC-5Val5A ..6.95

723 $ .50

350T-5,12, or 15V $1.10

LM305G $ .75

340K-12,15or24V.$1.50 340T-5, 6,8, 12,15

18or24V $1.10

320MS $ .75

LAS1412 + 12V3A $3.95

LINEAR CIRCUITS

LED READOUTS

FCS 8024-4 digit FND359L.A

C.C. 8" display $5.95 FND 503 C.C. .5" $ B5 FND510C.A..5" $ .85 DL-704-.3" C.C. $ .85

$ .60 DL-707C.A. .3"$ .75 DL747 CA..6" $1-50 HP3400.8"CA $1.95 HP3405.8-CC $1.95

LMD07 LM308 LM&4

LM387 - 1.25 LM563 - 2.25 LM556 - .45 LM55J - .65

567 - 1.10

CH756 CA30IB CA3346 CA3076

NE540L 603BCC N5696A

POSTAGE ADD 10% FOR ORDERS UNDER $20.00 RATES ADD 5% FOR ORDERS BETWEEN $20.00 AND $50.00

ADD 3% FOR ORDERS ABOVE $50.00

TERMS:FOB CAMBRIDGE, MASS. SEND CHECK OR MONEY ORDER. MINIMUM TELEPHONE, C.O.D. PURCHASE ORDER OR CHARGE $20.00 MINIMUM MAIL ORDER $5.00.

SOLID STATE SALES

P.O. BOX 74B

SOMERVILLE, MASS. 02143

TEL. (617)547-7053

WE SHIP OVER 95%

OFOURORDERSTHE

DAY WE RECEIVE THEM

1-800-343-5230

SEND 5.25 FOR OUR CATALOG FEATURING TRANSISTORS & RECTIFIERS. 145 HAMPSHIRE ST.. CAMBRIDGE. MASS. 02139

Each test subject is asked to make a pot of tea.

The engineer fills the kettle with water from the pitcher, puts it on the stove, brings the water to a boil, and makes the tea. When the physicist encounters the same situation, he thinks for a while, puts the tea into the cold water, etc, but eventually hits upon the solution. The mathematician takes a little longer, but finally he too solves the problem.

For the second part of the test, each subject is led into another room. In this room, again, there is a stove, a table with a pitcher of water, and a box of tea. The difference is that the tea kettle is now sitting on the floor.

When the engineer enters the room and is asked to make tea, he picks up the kettle, fills it with water, puts it on the stove to boil, and so on, as before. The physicist stops and thinks for a short time, then figures it out, and does essentially the same.

But the mathematician, as soon as he encounters the puzzle, simply takes the kettle from the floor and sets it on the table. Then he stops. He has reduced the problem to a previous case—one he has already solved. As far as he's concerned, nothing more need be done.

This trick of reducing a problem to a previous case may be funny or obvious, but it's also exceedingly valuable in computing, and in other fields. When calculating the factorial function n\ =n X (n-l)X(n-2)X ... X3X2XI, once you know how to calculate n\ you can easily get (« + l)I by reducing the calculation to a previous case. When trying to find the prime factorization of the numbers from 1 to n, once a single factor of a number is found, no more work need be done since the remaining number has already been factored, and is therefore a previous case. There are many other examples.

Music Generator uses this "reduction to a previous case" technique. After each transformation of a candidate bit pattern, the result is checked to see if it is smaller than the original candidate under consideration. If it is smaller, you know that it has been previously handled, and the program immediately skips on to the next candidate (specifically, it branches to line 1000 which is a NEXT I statement). By starting with the smallest candidate, 00000001, and working upward, the program produces a complete list of all the

82 February 1981 © BYTE Publications Inc

Circle 49 on Inquiry card.

Orange micro

'SPECIALIZING IN PRINTERS AND CRT'S"

CENTRONICS 737 (SSv)

NEC SPINWRITER

Word Processing Print Quality

• 18 x 9 dot matrix; suitable tor word processing • Underlining • proportional spacing • right margin justification • serif typeface • 50/80 CPS • 91/2" Pin Feed/Friction feed • Reverse Platen • 80/132 columns

High Speed Letter Quality

• 55 CPS • Typewriter quality ■ Bidirectional ■ Plotting • proportional spacing.

'■

CENTRONICS 737-1 (List $995) $780

CENTRONICS 737-3 (List $1045)

5510-5 RO, Serial, w/tractors (List $2995) $2625

5530-5 RO, Parallel, w/tractors (List$2970) $2599

EPSON MX80

Low-Priced Professional Print Quality

• 9 x 9 dot matrix • Lower case descenders

• 80 CPS • Bidirectional, Logic seeking • 40, 66, 80,132 columns per line • 64 special graphic characters: TRS-80 Compatible • Forms handling • Multi-pass printing • Adjustable tractors

EPSON MX80 (List $645)

SCall

OKIDATA MICROLINE SERIES

TRS-80 Graphics Compatibility

9 x 7 dot matrix • 80 CPS • 80, 132

1 columns — 64 shapes for charts, graphs &

diagrams • Double wide characters • 6/8

lines per inch • Up to 3 part copy • Friction

& pin feed • 200 M character head warranty

OKIDATA MICROLINE 80 (List $800) $599

OKIDATA M82 Bidirectional, Forms handling (List $960) $799

OKIDATA NI83 Wide carriage, 9 x 9 dot matrix (List $1260) SCall

^

BASE 2 850

The Micro Printer With The Most Features

• Graphics • Tractors/Friction Feed • 2K FIFO Buffer • RS-232 Serial, Centronics® Parallel, IEEE-488, 20 ma • TRS-80 Cable option • 100 CPS • Fast form feed • User programmable character set • 64, 72, 80, 96, 120, 132 Columns/line • Expanded characters • Automatic skip-over-perforation • Horizontal & Vertical tabs • Programmable vertical line spacing • Intel 8085 Microprocessor — over 40 software commands • Bidirectional, Logic-seek. (List $799) $749

BASE 2 850.

TOLL FREE (800) 854-8275

CA, AK, HI (714) 630-3322

At Orange Micro, we try to tit the right printer to your application. Call our printer specialists lor tree consultation.

ANACOM

Low Cost, High Speed, Wide Carriage

• 9 x 9 dot matrix • Lower case descenders • Wide carriage Adjustable tractors to 16" • 150 CPS, Bidirectional, Logic Seeking

ANACOM 150 (List $1350)

SCall

IDS PAPER TIGERS

Dot Resolution Graphics, quality print

• Up to 198 CPS • 8 character sizes • sophisticated dot resolution graphics • adjustable tractors to9V2".

IDS 445G 7 wire printhead, graphics (List $895) $ 795

IDS 460G9 wire printhead, graphics (List $1394) $1199

VISTA -'C^TOH dftllouMy

• 25 CPS (Optional 45 CPS) • Typewriter quality • Centronics parallel

• RS 232 Serial (Optional) • Proportional spacing • Bidirectional

• Programmable VFU • Self test • Diablo compatible • Friction feecf (Optional tractors) • 136 printable columns • Manufactured by C. ITOH. VISTA V300(C. ITOH) (List $1895) $1795

TELEVIDEO CRT'S

PRICES SLASHED!

TV|y12G I Please Call Toll Free TVI 920C f Prices are too low to ^■■^^ TVI Q^O I advertise

^^^k QUANTITY PRICING AVAILABLE ' v ' J^J'-' J

PRINTERS

CENTRONICS 730 RadioShack Line Printer II (List S795) $ 639

ANADEX 9500 wide carriage, graphics (List $1650) $ 1450

MALIBU 165 wide carriage, graphics, letter quality . . (List $2495) $ 2195

QUME 5/45 typewriter quality (List $2905) $ 2559 |

INTERFACE EQUIPMENT

APPLE II-BASE 2 parallel graphics interface boards cable $ %>■■

APPLE II- EPSON MX80

parallel graphics interface board & cable $ 110 I

SSM AIO BOARD Apple Serial/parallel interface (List $225)$ 175 |

MICROTRONICS Atari parallel interface $

ATARI 850 Interface module, serial/parallel $

TRS-80 CABLES to keyboard or Exp. interface *

NOVATION D-CAT direct connect modem $

CALL FOR FREE CATALOG

Phone orders WELCOME. Same day shipment for VISA, MASTER CHARGE, and AMERICAN EXPRESS. Personal checks require 2 weeks to clear. Add 3% for shipping and handling. California residents add 6%. Manufacturer's warranty Included. Prices subject to revision.

Orange fTlicro, mc

3148 E. La Palma, Suite E Anaheim, CA 92806

ORDERS FROM

CALIFORNIA, ALASKA, HAWAII AND

OUTSIDE OF U.S. (714) 698-8088

SAtSS INFORMATION, TECHNICAL, OR BACKORDERS, CALL {714} 698-0260

V'^334

'apple computer

Authorized Dealer

[CipplG//

ACCESSORY SPECIALS

DISK II DRIVE (add-on) 425

D.C. HAYES MICROMODEM II 319

GRAPHICS TABLET 655

INTEGER BASIC OR APPLESOFT II firmware card 149

SILENTYPE PRINTER with Interface card.. 515

APPLE II ACCESSORIES

CENTRONICS PRINTER

Int. card 185

PARALLEL PRINTER Int. card145 COMMUNICATION CARD

w/conn. cable 185

HI-SPEED SERIAL Int. card.. 145 DAN PAYMAR lower case kit. 55 MICROWORKS DS-65

DIGISECTOR 339

LAZER lower case adapter. ... 50 SSM AIO SERIAL/

PARALLEL kit 155

SSM AIO assembled & tested190 SYMTEC LIGHT PEN SYSTEM215 SYMTEC SUPER SOUND

GENERATOR 225

SVA 8 INCH DISK

CONTROLLER CARD 335

VERSA WRITER

DIGITIZER SYSTEM 215

VIDEX VIDEOTERM

80 COLUMN CARD 315

VIDEX VIDEOTERM

w/graphics ROM 335

LOBO DISK DRIVE ONLY... 385 LOBO DRIVE

w/cont. & DOS 3.3 4"

GPIB IEEE-488 (1978) Int 259

ARITHMETIC PROCESSOR

CARD 335

SPEECHLINK 2000

(64 Word Vocab.l 215

M&R SUPR-MOD

TV MODULATOR 30

CORVUS 10 MEGABYTE HARD

DISK DRIVE SYSTEM

w/pwr supply 4395

CORVUS CONSTELLATION.. 595 16K MEMORY UPGRADE KIT ITRS-80, APPLE II,

SORCERER 60

ABT NUMERIC INPUT KEYPAD

(specify old or new kybrd). 115 ALF MUSIC SYNTHISIZER.. . 235

BRIGHTPEN LIGHTPEN 32

M&R SUPER-TERMINAL

80 COLUMN CARD 335

SMARTERM 80 COL 335

Mountain Computer APPLE CLOCK/CALENDAR

card 225

SUPERTALKER SD200 SPEECH

SYNTHISIZER SYSTEM. . . . 245 ROMPLUS w/kybrd filter.... 165 INTROL/X-10 BSR REMOTE

CONTROL SYSTEM 245

INTROL/X-10 controller

card only 165

ROMWRITER SYSTEM 155

MUSIC SYSTEM

(16 voices/stereo) 465

A/D-D/A 16 CHANNELS 319

EXPANSION CHASSIS

(8 slotsl 555

APPLi II PLUS

OR APPLE II STANDARD

I6K0Fn°lV fW5 48K for *1049

DISK II DRIVE $.a9

w/controller & DOS 3.3 •»~~

*425

microsoft Z-80 SOFTCARD *199

APPLE II SOFTWARE

VISICALC 120

CCA DATA MANAGEMENT. 85

THE CONTROLLER General Business System 519

THE CASHIER Retail Management & Inventory system 199

APPLEWRITER Word Processor 65

APPLEPOST MAILING List system 45

DOW JONES PORTFOLIO

EVALUATOR 45

APPLE CONTRIBUTED

Volumes 1-5 w/manuals . . 30 -DESKTOP/PLAN by DESKTOP

COMPUTERS 85

APPLEBUG ASSEMBLER/

DISASSEMBLER 75

APPLE DOS TOOL KIT 65

PIMS Personal Information

Management System .... 23 ADVENTURE by

MICROSOFT 27

SUB-LOGIC FS-1

Flight Simulator 34

SARGON II Chess

by HAYDENICass.) 27

FORTRAN 165

DOS 3.3 49

APPLE PLOT.. .. 60

TAX PLANNER 65

SARGON II Chess

on Diskette 32

TRILOGY OF GAMES 27

SPACE GAME ALBUM 38

SPACE INVADER (Cass.). . . 18 SPACE INVADER (Disk.). . . 23 SYBEX APPLE-80

8080Simulator 17

FORTH MbyPROGRAMMA

SOFTWARE 45

SINGLE DISK COPY

ROUTINES 17

APPLEBUG DEBUGGER. . . 27 APPLESOFT UTILITY PROGRAMS BY HAYDEN ... . 27

The CORRESPONDENT 35

ASTEROIDS IN SPACE .... 19

HEAD-ON 25

3-D ANIMATION PACK. . . . 53 BATTLESHIP

COMMANDER 23

FASTGAMMON 26

STAR CRUISER 24

TRANQUILITY BASE 24

More software available Please write us for a list.

Circle 50 on Inquiry card.

i*5*

>■'.?.-A |

INTERNATIONAL CUSTOMERS:

T E

ANSWER "BETA" ATTENTION "CRUS' COMING SOON....

- * ; p/.: . W;

LONDON P4A/S BERLIN CAIRO RIYADH JOHANNESBURG

o / ;o c/ry

'(/c»

>£9

^

EXIDY

ATARI

OSI

Please

Call

For

Best

Price

SORCERER II COMPUTER

16.32K & 48K VERSIONS AVAILABLE

S-100 EXPANSION UNIT 37B

WORD PROCESSING PAC 179

DEVELOPMENT PAC 89

A

ATARI*

PMC-80

THE TRS-80 'WORK ALIKE' 16K LEVEL II ONLY $579

Completely compatible with Radio Shack TRS-80 Level II software and peripherals. Features include: Level II Basic, Video & Ch. 3 TV output. Built in Cassette, 40 pin interface conn., 16K User RAM memory, Expandable to 48K.

For more information, please call or write.

41095

WATANABE MIPLOT

for more info please call or write

16K FOR /5J5J

ATARI 800

PERSONAL COMPUTER SYSTEM

400 COMPUTER 479

820 PRINTER (40 col.l 459

810 DISK DRIVE 559

410 PROGRAM RECORDER 59

815 DUAL DISK DRIVE 1199

822 THERMAL PRINTER I40 col.l 369

825 PRINTER (SO col. imp.1 795

850 INTERFACE MODULE 175

ATARI 16K RAM MODULE 155

LIGHT PEN 65

ACOUSTIC MODEM ICAT) 169

COMPUTER CHESS 35

SPACE INVADERS 19

STAR RAIDERS 49

SUPER BREAKOUT 35

3-D TIC-TACTOE 35

VIDEO EASEL 35

MUSIC COMPOSER 49

VISICALC DISK 129

LEEDEX VIDEO 100 139

SANYO 9" B&W 165

SANYO 12" B&W 255

PANACOLOR 10" COLOR 329

NEC 12" HI-RES COLOR 875

NEC 12" LORES COLOR 399

NEC 12" GREEN PHOSPHER(P3il. . 239

TELEVIDEO 912B&C 698

TELEVIDEO 920B & C 745

C4PMF *1699

PLOTTERS VIDEO MONITORS PRINTERS

Cassette Disk

SPACE INVADERS 19 29

SARGONII 30 35

FORTH N/A 69

OS 65-D V3.3 N/A 79

MDMS PLANNER •■ N/A 100

GRAPHICS I N/A 35

daci N/A 45

ASSEMBLER/EDITOR 40 N/A

EXTENDED MONITOR 20. .... N/A

PASCAL & FORTRAN I4P & 8P only). N/A 450

When ordering please specify system.

ANADEX DP-8000 775

ANADEX DP-9500 1350

BASE 2 649

CENTRONICS 737 825

PAPER TIGER IDS-460 w/graphics 1195

PAPER TIGER IDS-440 wfgrophics 895

NEC SPIN WRITER 2550

TRENDCOM 200 519

SILENTYPE Wflnt 515

EPSON TX-80 w/graphics 729

EPSON MX-80 132 col 620

QUMESPRINT5 2560

ORDERING INFORMATION: Phone Orders invited using VISA, MASTERCARD. AMERICAN EXPRESS, or bank wire Iranslers VISA S MC credit card service charge of 2V AE credit card service charge ol 5% Mail orders may send charge card number (include expiration date) cashiers check, money order or personal check (allow 10 business days to clear} Please include a telephone number with all orders Foreign orders (excluding Military PO's) add l0°o lor shipping all funds must be in US dollars (letters ol credit permitted) Shipping, Handling and Insurance in U S add 3°o (minimum Sd 00) California residents add 6°0 sales tax Our low margins prohibit us to send COD or on purchase orders or open account (please send lor written quotation ) Alt equipment is subject to price change and availability Equipment is new and complete with the manufacturer warranty We do not guarantee merchantibihty of products sold All returned equipment is subject to a 1 5°o restocking fee We ship most orders within 2 days. WE ARE A MEMBER OF THE BETTER BUSINESS BUREAU AND THE CHAMBER OF COMMERCE. RETAILSTORE PRICES MAY DIFFER FROM MAIL ORDER PRICES.

PLEASE SEND ORDERS TO: CONSUMER COMPUTERS MAIL ORDER, 8314 PARKWAY DRIVE, GROSSMONT SHOPPING CENTER NORTH, LA MESA, CA. 92041

Circle 50 on Inquiry card.

Choices for actual locations:

P = 0

Q = 2 R=2 RNDPTR = DD (hexadecimal) RNDNUM = DE (hexadecimal) D = EC (hexadecimal) V = F3 (hexadecimal) N =F4 (hexadecimal

;P,Q,R occupy "USR(X)" storage area!

-.random numbers in PET's RND(X) location ;in PET's "EOT character" area

;V,N in tape buffer pointer area

Ml =033A (hexadecimal) = 826 (decimal)

M2 = 036C (hexadecimal) = 876 (decimal)

I =03D8 (hexadecimal) = 984 (decimal)

Music table occupies 03D9 thru 03E0 (hexadecimal) = 985 thru 992 (decimal).

INTR VLTAB = 03E1 = 993

Interval table occupies 03E1 thru 03E8 (hexadecimal) = 993 thru 1000 (decimal).

NOT ETA B = 03E8 = 1000

Note table occupies 03E8 thru 03FF (hexadecimal) = 1000 thru 1023 (decimal). Note overlap with interval table.

Contents of tables:

01234567 89ABCDEF

03E0: — 00 00 04 F9 07 F5 OC FB ED EO D3 C7 BC Bl A7

03F0: 9D 94 8C 84 7C 75 6E 68 62 5C 57 52 4D 49 45 41

Algorithm Description

Ml.(Initialize) Point PET hardware interrupt vector to M2. SET Q, R, and N to 8; zero

music table 1(1), 1(2) 1(8).

Set P, V, and D to 1.

M2. (Interrupt enters here) Decrement note duration counter D; if result is nonzero, go to PROCEED below.

M3.(Next note) Reset D to 4 (or other chosen length of note to be played, in units of y60 second). Look up interval I(P) and add that to note N, staying in allowed range (0 to 23). Decrement pointer P; if result is nonzero, go to step M6.

M4. (A measure of eight notes has been completed) Reset P to 8. Decrement voice V (bit pattern making sound) by 4 (or other choice), and if result is negative, reset V to maximum (=85). Change voice of note (POKE 59466, V). If counter Q is nonzero, invert interval I(Q) by negating value of I(Q), decrement Q and go to step M6.

M5.(All eight inversions have been completed) Reset Q to 8. Replace interval I(R) by another "randomly" chosen interval from the allowed table of intervals (in musical notation, table contains thirds, fifths, octaves, etc).

Decrement R, and if R becomes 0, reset R to 8.

M6. (Play next note) Play new note NOTETAB(N). looked up in notetable. (POKE 59464, NOTETAB(N).)

PROCEEDJump to PET's normal interrupt-handling routine (E685).

To use Tiny Timesharing Music give command SYS(826) to turn music on and off. (You must turn it off before tape operations, since the PET uses the same interface chip when reading/writing tapes )

distinct-tone-quality bit patterns. (Patterns 00000000 and 11111111 are not included, since they're inaudible.) When written as binary numbers, the legal (irreducible) bit patterns have some interesting resemblances to the set of prime numbers (numbers that have no positive factors except themselves and 1). They are quite dense at the lower end of the range of available numbers, but become fewer and farther between as the candidate numbers get larger. There's a simple reason for that: if a large number is chosen at random, it's likely that

some combination of the operations ROL, INV, and REV will be able to transform it into a smaller number, a previous case. (Similarly, there is a good chance that a large integer chosen at random has a factor among the many smaller integers between itself and 1, so the density of prime numbers decreases.) However, even as you go to higher numbers, an occasional pair of distinctive bit patterns appears, separated by a single even number. Among the 8-bit musical patterns, the pair 43 = 00101011 and 45 = 00101101 is a good example of

such a "musical-pair"; if you look at 16-bit patterns, which potentially range from 1 thru 65535, pairs such as 11059, 11061 can be found. Prime numbers can also come in such pairs; as far as I know, however, there is no proof that an infinite number of prime pairs exist. There may be other analogies between the theory of primes and the distinct-voice musical bit patterns—I'd be interested in hearing about your discoveries.

From Tones to Music

I began this discussion with a look

86 February 1981 © BYTE Publications Inc

Ml:

LOOP1:

M2: M3:

OVER1:

OVER2:

M4:

OVER3:

M5:

M6:

PROCEED:

SEI

LDA $0219

EOR #$E9

STA $0219

LDA $021A

EOR #$E5

STA $021A

LDA $E84B

EOR #$10

STA $E84B

LDY #8

STY Q

STYR

STYN

LDA #0

STA I,Y

DEY

BNE LOOP1

INY

STYP

STY V

STYD

CLI

RTS

DEC D

BNE PROCEED

LDA #8

STAD

LDXP

LDA I,X

CLC

ADC N

BPL OVER1

ADC #$0C

BPL OVER2

CMP #$18

BCC OVER2

SBC #$0C

STAN

DECP

BNEM6

LDY #$8

STYP

LDA V

SEC

SBC #4

BPL OVER3

LDA #$55

STA V

STA $E84A

LDXQ

BEQM5

SEC

LDA #0

SBC I,X

STAI.X

DEC Q

BPLM6

STYQ

INC RNDPTR

LDX RNDPTR

LDA 0,X

EORRNDNUM

STA RNDNUM

AND #$7

TAX

LDA INTRVLTAB.X

LDXR

STA I,X

DECR

BNEM6

STYR

LDXN

LDA NOTETAB.X

STA $E848

IMP $E685

.'disable interrupts during changeover

;PET hardware interrupt vectors thru $0219,021A

;changes normal contents, $85, to $6C, and vice versa

.'changes $E6 to $03, and vice versa

; = 59467, auxiliary control register

;change $00 to and from $10 (free-running shift out)

;now initialize page zero music counters

;clear out music table in 1+ 1 thru 1 + 8

; initialize more page zero counters

;re-enable interrupts

;this is where interrupt vector was changed to point to

;keep playing same note for duration D

;value may be changed to vary tempo.. .4 thru 16 is nice.

;fetch next interval from music table to be added to note N

;if displacement made N negative, add 12 to move up an

octave

;always take the branch (this could be omitted to save 2

bytes)

;make N less than 24

;subtract an octave to get in range

;move note pointer back one ;go to play note if nonzero

;reset pointer P

;change voice (tone quality, bit pattern shifted out) used ;change this number 4 if other patterns are desired

;reset to maximum interesting pattern ( = 85 decimal)

; = 59466, shift register

;branch if it's time to change an interval randomly

.'invert an interval (negate it) in music table

;always take branch

;reset Q to 8

;move pointer forward

;get a "random" number from page zero

;mix its bits with previous "random" ones

;save them for future mixing

;mask out bits to get a "random" # in range 0 thru 7

,'prepare to take an interval from INTRVLTAB table

;find out which music table entry to alter linsert new "random" interval

,'reset R to 8 if necessary ;find what note to play

; =59464, controls shift rate

;return to normal interrupt-handling chores

Listing 3: Tiny Timesharing Music. This interrupt-driven program runs concurrently with other PET programs, and uses their changing data to update its toneparameters (see the text box "Algorithm Description"). The interrupt occurs every y60 of a second to cause the PET to check the keyboard for closed keys.

at Fourier analysis, and have wandered through a bit of group theory in looking at shift-registergenerated tones and what they sound like. I'd like to close with a practical application of this material.

I often run fairly long programs, and it can be boring to stare at a static video screen, waiting for the results to appear. Then, too, I sometimes become paranoid and suspect that the machine has crashed, leaving me to wait forever. Well, I thought, why not put a little musical theory to work? Why not have music while I'm waiting for the programs to finish?

The more I thought about it, the better the proposal sounded. The PET is always interrupted sixty times per second, to scan the keyboard and update the internal clock. (This happens as long as the interrupt-disable flag hasn't been set in the 6502 microprocessor; the flag is rarely set during normal operation.) At each interrupt, the microprocessor branches to the address stored in memory locations 0219,021A. Normally, these addresses point to hexadecimal location E685, but by changing the address pointed to, I could take control once every V60 second—and play music!

The requirements that a good interrupt-driven music-generation program must meet are rather severe:

1. It must produce interesting musical patterns, neither too repetitious nor too chaotic.

2. It must be fast so that the main program does not slow down appreciably while music is playing.

3. It must be small; the main programs must not be squeezed out of memory or restricted by the music generator.

The program shown in listing 3 resulted. Tiny Timesharing Music meets the third requirement by occupying only the memory at locations 826 thru 1023 (second cassette buffer), plus five locations on page zero. It satisfies the second requirement by being fast; running at normal

February 1981 © BYTE Publications Inc 87

pppfc* ][

i6K lomputer

DISK with CONTROLLER NEW DOS 3.3 $535 without... $429 Nearly Everything for Apple

WE WILL BEAT

ANY ADVERTISED PRICES

ON MOST ITEMS IF MERCHANDISE

IN STOCK

APPLE SOFTWARE

Adventure by Microsoft 29

Apple Bowl 19

Apple Stellar Invaders 19

Assembler/Disassembler 69

Applebug Debugger 29

AppleGraph & Plot Sys 59

Applepost Mailing List Sys 44

Applesoft Cassette Demos 29

Applesoft Util. Prog. — Hayden 29

Applewriter Word Processor 65

Asteroids in Space 19

Autostart ROM Pkg 59

Battleship Commander 19

Bill Budges Space Game Album 39

Bill Budges 3-D Graphics/Tool 39

Bill Budges Trilogy of Games 29

Cashier Retail Mgmt. Sys 199

Checkbook Cassette 19

Contrib. Vols. 1-5 w/man 29

Controller Bus. Pkg 514

Cosmos Mission/Disk 25

CCA Data Mgmt. Sftwe 84

3-D Animation Pack 55

Desktop Plan Sftwe 79

DOS Tool Kit 65

DOS 3.3 Upgrade 49

Dow Jones Portfolio Evaluator 45

Fastgammon 23

Forth II by Programma 45

Fortran for Language Sys 159

Head-on 25

Integer Basic Cassette Demos 29

PASCAL Language Sys 459

Sargon II Chess Game disk 34

Shell Games 29

Single Disk Copy Routines 17

Space Invader 25

Star Cruiser 24

Stellar Trek 23

Sub-Logic FS-1 Fit. Sim./disk 34

Sybex Apple-80 8080 Sim 19

Tax Planner 99

The Correspondent 35

Tranquility Base 24

Visicalc by Personal Sftwe 119

Complete Peachtree Business Package for Apple

AND MUCH MORE . . .

CALL

PHONE ORDERS

MON. - SAT. 8 to 6 P.S.T.

APPLE COMPUTER INTERFACE CARDS

HiSpeed Serial Int. 7710A 145

Applesoft II Firmware Cd 149

Centronics Interface Cd 179

Apple Clock/Calendar Cd.

by Mtn. Comp 225

Comm. Cd. & DB25 Cable 179

Integer Basic Firmware Cd 149

Parallel Printer Cd 139

CCS Parallel Print Cd. 7720A 155

ROMPLUS w/keyboard filter 165

ROMPLUS (keyboard filter extra) ... 159 SSM AIO Serial/Parallel I/O

Assembled & Tested 189

Serial Interface Cd 139

ACCESSORIES

Apple Joystick 47

ABT Numer. Input Keyboard A or B 114

A/D D/A Board by Mtn. Comp 319

Arith. Processor 7811 A or B 339

Clear Cover for Apple Computer 25

COPYROM by Mtn. Comp 51

Corrus 10MByte Disk w/pwr. supp. 4395

Dan Paymar L.C. Kit 1 or 2 59

Extender Board 27

GPIB by CCS model 7490A 259

Graphics Input Tablet 649

Hayes Micromodem' 319

Introl X-10 Remote Control Sys 239

Introl X-10 Controller Only 169

M&R Sup-R-Term 80 column board . 329

Microsoft Z-80 Soft Card 295

Novation Cat Modem 159

Programmable Timer CCS 7440A ... 159

Prototyping Hobby Card 22

ROMWRITER by Mtn. Comp 149

Speechlink 2000/64 Word Vocab. ... 215 SuperTalker Speech Synthesizer.... 239

Symtec Light Pen 214

Versa-Writer Digitizer

Drawing System 209

Videx Videoterm 279

"BEST PRINTER VALUE IN THE WORLD' Check our prices on THE ULTIMATE IN QUALITY

Epson Rinters

APPLE & MOST OTHER COMPUTERS

NEW! MX80

40, 80, 132 columns

LIST $&45'

TX 80 w/Graph/cs

LIST p£3

Apple Controller & Card & Cable

LIST |M<T

OUR PRICE

CALL

• Most reliable small printers ever sold!

• Uses standard printed paper.

• Graphics option transfers screen image directly to paper.

IF

A

ATARI

MAKES

IT, WE

SELL IT

Assembler/Editor 45

Atari 400 Computer 439

Atari 820 Printer 429

Atari 810 Disk Drive 499

Atari 410 Program Recorder 69

Atari 16K RAM Module 149

Atari Basic ROM 45

Atari Visicalc 129

Basketball 30

Video Easel 30

Super Breakout 30

Music Composer 45

Computer Chess 30

Star Raiders 39

3D T ic-Tac-Toe 30

Joystick 19

Space Invaders 19

PRINTERS, MONITORS, DISCS

Anadex DP8000 795

Anadex DP8000AP 795

Color Monitor 375

Daisy Wheel Printer 1795

MPI 88T 595

NEC Spinwriter #5510 2595

Paper Tiger 440 w/Graphics 895

Paper Tiger 460 w/Graphics 1195

Silentype w/interface Cd 510

Sanyo 9" B&W 169

Sanyo 15" B&W 259

NEC Green Screen 12" 239

Dysan disks (pkg. 10) 50

Memorex disks (pkg. 10) 40

Opus disks (pkg. 10) 35

Televideo 912C 699

Televideo 920C 749

Verbatim disks (pkg. 10) 30

LEEDEX VIDEO 100 12" BlackS White $119

jfe MONTHLY jfc ^ SPECIALS *

CENTRONICS 737 $737

cable extra

OUR PRICE CALL

LARGE STOCK OF SOFTWARE & ACCESSORIES

(714) 579-0330 • MAIL TO: 1251 broadway, el cajon, ca. 92021

Circle 51 on inquiry card.

speed it uses about 18 /ts every %0 second—only 0.1% of the machine's time. (Changing notes at top speed uses less than 0.4% of the time.) As for whether or not it meets the first criterion, you'll have to judge for yourself: "interesting" is in the ear of the beholder. I enjoy it, although it's certainly nowhere near Bach's Art of Fugue...then again, nothing is.

The algorithm description which accompanies this listing (see the text box "Algorithm Description") should make its method of operation clear. The theory of music is beyond the scope of this article (and me!), but in brief, the program works as follows: first it generates eight intervals, chosen from a musically "nice" set of possibilities (see Arthur Benade's book, and other references, for more details). Beginning with a base note, eight notes are played, each related to the previous note by one of the chosen intervals. After a measure of eight notes is completed, the bit pattern (voice) being used by the shift register is changed, one of the eight intervals is inverted, and another measure is played. (Inversion simply amounts to a sign change: an interval

of +7 (a fifth) is inverted to —7.) After all eight intervals have been inverted, one is replaced by a new, randomly-chosen interval, and the whole process is repeated. The "random" numbers are influenced by the contents of page zero, so if the user is doing something, or running any program, the musical patterns produced will never repeat for long.

As always, I will be delighted to learn of any improvements that readers make in this musical program. The best way to test ideas for musical pattern generation is to run them as non-timeshared BASIC programs. Then they're easily modified and debugged, and if they sound good, they can be coded in assembly language. In Tiny Timesharing Music as presently written, it's easy to change the tempo of the notes: just POKE 881,X where X is the length of the notes in units of V60 second (values of X between 4 and 16 seem to work best). The contents of memory location 918 govern the changes between one voice and the next: the number there (and in location 922) may be changed to vary the sequence of bit patterns used. The table of

musical intervals in locations 993-1000 can be varied according to taste, as can the table of notes (1000-1023; note that one table entry is in common, to save space). I use a digital approximation to a welltempered scale, but you may prefer another choice.!

References

1 .Apel, Willi and Ralph T Daniel. The Harvard Brief Dictionary of Music. Pocket Books, 1960.

2.Benade, Arthur H. Horns, Strings and Harmony. Doubleday Anchor Books, 1960. 3.BYTE magazine, September 1977. Several interesting and useful articles, especially one by Hal Chamberlin, page 62. 4.Crawford, Frank S. Waves—Berkeley Physics Course, Volume 3. McGraw-Hill, 1968.

5.Feynman, Richard P. The Feynman Lectures on Physics, Volume 1, lecture 50. Addison-Wesley, 1963. 6.Foster, Caxton C. Programming a Microcomputer: 6502. Addison-Wesley, 1978.

7.Kinnard, J R. "Generating square waves with the PET," PET User Notes, Volume 1, Number 3. Published by Gene Beals, POB 371, Montgomeryville PA 18936. 8.Rabiner, Lawrence R and Charles M Rader, Editors. Digital Signal Processing. IEEE Press, 1972.

"^-^^ Anti-Static a j^~^

DustCcwers

Protect your computer and accessories.

• Anti-static vinyl helps prevent static from damaging sensitive components and causing faulty operation.

• Double-fold stitching will not rip out and is unmatched for strength and long life.

• Heavy gauge textured vinyl blends with any decor and folds easily for convenient storage.

• Over 1000 custom designs gua ranteed to fit precisely.

• 100% satisfaction guarantee means we stand behind our product.

Yes, there are differences ,«

in Dust Covers. Differences which can be vitally important to the proper ■ "^58

functioning of your system.

THE BEST DUST COVERS AT ANY PRICE

MOST PRICED

$7.95 to $11.95

PLUS POSTAGE AMD

HANDLING

VISA-MasterCharge

At Cover Craft we've manufactured the highest quality Dust Covers for the electronics industry for more than six years. We've been selected by major equipment manufacturers to make covers for their products. Our covers are in use in every state and in more than 50 countries. We know what it takes!

So visit your dealer or contact Cover Craft for our latest catalog and list of over 200 dealers.

C COVER CRAFT P.O. BOX 555 • AM H ERST, N H 03031 • (60:

(603)889-6811

90 February 19B1 © BYTE Publications Inc

Circle 52 on Inquiry card.

BASIC SOFTWARE LIBRARY

NOW • 10 • Volumes and Growing

For Homeowners, Businessmen, Engineers, Hobbyists, Doctors, Lawyers, Men and Women This month we will highlight some of the many extra assets contained in Volumes

"Volume I $24.95

Business & Personal Bookkeeping Programs

'Volume II $24.95

Math & Engineering

'Volume III $39.95

Advanced Business Programs

'Volume IV $9.95

General Purpose Programs

'Volume V $9.95

Experimenters Programs

'Volume VI $49.95

General Ledger Programs

"Volume VII $39.95

Professional Programs

"Volume VIII $19.95

Homeowner Programs

"Volume IX $19.95

Travelers Programs

"Volume X $69.95

Total Business Package

* See Dec. 80 Byte Ad for complete table of contents.

VOLUME III - ADVANCED BUSINESS PROGRAMS

Tens of thousands of satisfied customers have purchased this volume. It is one of our three most popular volumes and has been for the last four years. While containing only eight proprams with an average program length of 12K Bytes they have proven to be real winners! The Billing, Inventory and Payroll programs are designed to be used with non-disk computer systems and just as most such systems can be upgraded to disk operating, modification details are already included in this volume so that at the same time you upgrade your system you may convert these programs for disk usage. Sold for $1500 each, nationally, for several years before inclusion in our software library, these programs will print paychecks, customer bills, mailing labels, tabulated reports and allow over a dozen different modes of operation. To assist the businessman in making some costly decisions we have some very special programs that will help — schedule shipments of goods based on different demands, assign resources and people power efficiently; based on your priorities, analyze the risk factors for certain capital investments, compute the intrinsic value of stocks and lastly to compute the effects on bond yields when planning a switch. All of the programs contained in this volume are modular in structure (comprised of subroutines for each main function) allowing you to use the subroutines separately or to link them together to generate more highly specialized programs.

VOLUME X - A TOTAL BUSINESS SYSTEM

This program was sold for years for over $10,000, now yours for only $69.95.

This volume contains the most comprehensive business — accounting — financial program package available in the micro field. Set up to handle businesses using the accrual system and standard double entry ledgers it can also be used by cash system businesses. Computer system requirements are at least 24K Bytes of free memory, 100K Bytes minimum of disk storage, and a printer. The programs will operate under Microsoft Disk Extended Basic and also under "M Basic" on those systems equipped with CP/M. The programs in this volume will perform all necessary bookkeeping and accounting functions presently being handled by clerks and accountants. Besides providing routine business functions such as: A/R, Payroll accounting, Billing, Inventory control, etc.; there are sections for Fixed Asset accounting, maintenance of mailing lists, Taxes (both quarterly & annually), a comprehensive A/P section and a special Financial section that provides you with Profit & Loss statements and Balance Sheets — whenever you want them. It performs all check writing functions and the Check Register routine even allows for the addition of manually written checks. Eliminates the need for multiple recordings of the same transaction. Sales entries are made once, when the sale is made, the program will them update Cash on Hand or A/R, Inventory for Sale, and your Daily Sales Report — PLUS cut an immediate invoice; if desired. Another "special" feature of this package allows for FULL updating of all data files including customer and inventory data, daily sales, checks, assets, etc. on a daily basis, or weekly, or even hourly if you have specialized needs that can only be met in this way. Overall the program routines are about 80K Bytes long and automatic paging techniques are used to allow small systems to utilize the programs.

Almostevery single program included in these volumes will run in every Computer system that operates in Basic. A few changes may be required for some Basics but most of these changes are covered in one of the Tables and Appendices included in Volumes III, V, VI, VIII, and X.

Volume VI — Disk programs are compatible with TRS-80 disk basic

The disk programs in Volumes VI, VII and X are written in (CP/M) M Basic and Disk Extended Microsoft Basic. Other programs written in 8K Basic.

Unconditional Money Back Guarantee.

Add $1.50 per volume handling, all domestic shipments sent U.P.S. except APO and P.O. Box which go parcel post. Foreign orders add $6.00/volume for air shipment and makepayable in U.S. dollars only.

AVAILABLE AT MOST COMPUTER STORES

Master Charge and Bank Americard accepted.

Our Software is copyrighted and may not be reproduced or sold.

Unlike others we have NOT raised our prices in five years

KEMCO, LTD.

P.O. Box 2096 Ashland, VA 23005

Sales HOTLINE 804-798-1147

IN GERMANY

Ing. W. Hofacker, GmbH Holzkirchen, W. Germany

IN HOLLAND

Nanton Press B.V. Bilthoven, Holland

III

IN USE TODAY

COMPUTER FORMS KIT

with continuous business forms for small computer systems

Each kit contains samples, programming guides, flyers, prices and order forms for checks, invoices, statements, envelopes, stock paper and labels to fit almost every computer system.

• Available in quantities of 500, 1,000, 2,000 4,000, 6,000

• Low Prices (500 checks only $32.50)

INVOIBB

jzt

XT

itwy*,

ZET

Z3ZT

• PAST SERVICE — It is our policy to ship within 6 working days following our receipt of your order.

• MONEY BACK GUARANTEE — If for any reason you are not completely satisfied, your money will be promptly refunded.

Fasf Service by mail or. . .PHONE TOLL FREE 1 + 800-225-9550

Mass. residents 1 + 800-922-8560 8:30 a.m. to 5:00 p.m. Eastern Time Monday — Friday

Please Ship FREE Kit To: Name

CODE 460

Company

Street

City, State and Zip

Phone

Computer make & model

f '3 „ Nebs. _

*mm — — — — ■ Computer Ftnms-J

78 HoltisStreet, Groton,Mass. 01450

A division of New England Business Seivice, Inc. 92 February 1981 © BYTE Publications Inc Circle 53 On Inquiry Card.

Programming Quickies

Converting Pitch to Frequency

Robert Katz, 248 E 90th St, #3B, New York NY 10028

This program converts pitch to frequency and can use either the piano tuner's scale (based on a perfect fifth interval), or the scientific, or "just," scale (based on a perfect octave interval). The scales are equally tempered in either case.

The program is written in RPN (reverse Polish notation) for a Hewlett-Packard calculator. Step 8 includes a GTO instruction. If your calculator has labels instead of step numbers, use a label at steps 8, 10, 32, and 35.

To use the program, place a number from 1 to 7 in the x register. This represents one of the notes from C to B in the 12-note scale. To indicate the standard "whole" tones, use a whole number (such as 1 for C, 6 for A, etc). To indicate an accidental, use an integer plus 0.5 (6.5 for A#, 2.5 for D#). If the tones are to be in the octave of middle C, make sure a 0 is contained in the y register. Otherwise, the number in the y register should be an integer representing the number of octaves above or below middle C. For example, 5.5, —2 represents G§, two octaves below the octave of middle C. Once the pitch has been entered, all you have to do is press R/S. For example, enter (6, 0) and press R/S. This will display 440, which is the pitch of A in the octave of middle C.

The formula is:

261.25 X (-3T )Pl+P2

Listing 1: A program to convert pitch to frequency. This listing is in the RPN (reverse Polish notation) for a Hewlett-Packard calculator. If your calculator uses labels instead of step numbers, a label must be used at steps 8, 10, 32, and 35. In a calculator with continuous memory, steps 15 thru 21 and steps 24 thru 29 can be replaced with a constant recalled from memory.

1

f fixO

20.

q 1/x

?

1

21.

f r

a

22.

x~y

4

2

23.

f r

S

X

24.

2

6,

5

25.

6

7.

f x<y

26.

1

8

GTO 32

27.

q

i

28.

2

in.

x~y

29.

5

11.

1

30.

X

17

2

31.

GTO 00 (or q RTN)

13.

X

32.

1

14.

+

33.

1

IS.

1

34.

16.

35.

GTO 10

17.

5

18.

ENTER

19.

7

WHY CIS COBOL

LETS YOUR

MICROCOMPUTER

PERFORM LIKE A

MAINF

Now, you can use a microcomputer for sophisticated business applications ... because now there's CIS COBOL. Micro Focus developed this COBOL so your microcomputer can run the same programs as a minicomputer or a mainframe.

CIS COBOL is Micro Focus' Compact, Interactive, Standard COBOL which offers the advantages of COBOL... powerful data structure features, Englishlike language, existing programmer expertise... to provide you with a full commercial language. You won't be restricted by size either: a 64K byte microcomputer will compile up to 8000 lines of COBOL, more if the program's split into dynamically loaded modules.

Choose a Compact Compiler.

The Compact compiler runs on 32K byte microcomputer systems. Its powerful subset includes full support for random, indexed and sequential files.

Orchoose the Standard Compiler.

The Standard CIS COBOL compiler requires a minimum 48K of user RAM. A super-set of the Compact compiler, implementing ANSI 74 COBOL to Federal Low-intermediate Level.

The same CIS COBOL extensions for conversational working, screen control, interactive debugging, and special peripheral sup port are in both compilers. And there are more reasons to consider CIS COBOL:

• It conforms fully to the ANSI 74 standard, so programs are portable upwards and downwards to minis or mainframes.

• Its interactive features enable mainframe programmers to get results fast... working on inexpensive microcomputers.

Forms

The FORMS utility lets you build a screen layout online at the CRT. Then it automatically generates COBOL record descriptions for inclusion in your program.

Forms-2

A superset of FORMS, it eliminates the need to write simple data entry and inquiry programs, because the programs can be automatically generated from screen definitions.

Environment

CIS COBOL products run on the 8080 or Z80 microprocessors under the CP/M* operating system, and on the LSI-11 or PDP-11 processors under RT-11. They are distributed in a variety of disk formats and come with a utility that enables you to use any make of CRT.

OEMs

Intel has adopted CIS COBOL and offers it (as iCIS-COBOL) for their Intellec and

Intellec II systems. Ideal for OEM's or private label, CIS COBOL was developed entirely by Micro Focus. Send inquiries for CIS COBOL object packs and application vendor terms to MICRO FOCUS or its licensed distributors. Distributor terms also available from MICRO FOCUS.

Send me more information for: B2

□ Single Copy Users

□ Reseller and Distributor Licensing

Name

Title

Company

Address

City/State

Zip/Phone

Computer Model. Version of DOS_

MICRO FOCUS'

Micro Focus Inc. ■ 1601 Civic Center Drive ■ Santa Clara ■ CA 95050 • Tel: (408) 984-6961 • Telex: 171-135 MISSION SNTA

U.K. Office • 58 Acacia Road • St. Johns Wood • London NW8 6AG • Tel: 01 722 8843 ■ Telex: 228536 MICROF G

CIS COBOL distributors include: Vector Graphic, Onyx Systems, Altos Computer Systems, Lifeboat Associates, Research Machines, Telecomputing, Modular Business Systems, Rair, Midlectron, Rostronics and Johnson-Laird Inc. tlntellec is a trademark of Intel Corp. *CP/M is a trademark of Digital Research Inc.

BYTE February 1981 93

where Pi is a power within the octave of middle C. P2 is a power that will reach any octave above or below middle C. Steps 15 thru 21 compute the seventh root of 3/2, which is the relationship of a semitone within the pianotuner's scale, based on perfect fifths and stretched octaves. Replace steps 15 thru 21 with the twelfth root of 2 and you will have the standard, perfect octave scale. When using the perfect octave scale, you may have to change steps 24 thru 29 to 261.63 to obtain an A 440. Steps 24 thru 29 are the frequency of middle C, on which the program is based. Note also that steps 32 thru 35 are a correction factor based on the half step between E and F in the scale.!

BYTE's Bits

NSF Awards Education Grant

The NSF (National Science Foundation) has awarded Educational Solutions Inc a grant for the development of courseware that will demonstrate new ways to teach numeration,

$115.00 UNI QUANTITY

A handful of compact switching power St the incredibly low price of$115!

But don't be mislead by price. This is no stripped down, coverless pretender that tries to pass as a switcher.^

POWER-ONE'S new SD Series is a true high performance switching power supply in every sense of the word. It meets-impressive specifications while employing the absolute latest state-of-the-art power conversion techniques. Yet it's smaller, lighter, and more reliable than the rest.

All at a cost that combines affordability with the finest features of switching technology. The result is a dramatic new dimension in switching power supply value.

See for yourself. For fast action, write or phone for our new 1980 Catalog with complete details on the exciting new SD Series. ModelsChart

MODEL

VOLTAGE

CURRENT

SD5-10

5V

10A

SD12-4.2

12V

4.2A

SD15-3.4

15V

3.4A

SD24-2.1

24V

2.1A

SD28-1.8

28V

1.8A

mmwm°oi

d.c. power supplies

Power-One, Inc. (805) 484-2806

Power One Drive • Camarillo, CA 93010 (805)987-3891 • TWX 910-336-1297

addition, and subtraction. The New York City-based research and development organization's approach stresses learning through insight and practice rather than rote memorization. Feedback from the instructor helps guide and refine the student's growing insight. According to Educational Solutions's hypothesis, perceptual activities, feedback, and practice eventually teach the student practical skills.

Under the provisions of the grant, Educational Solutions must first produce a prototype of the courseware, then test it on public school students. After analysis, the courseware will be revised and prepared for distribution.

OSU's TABS Project

The College of Education at OSU (Ohio State University) is busily at work on project TABS. The purpose of this project is to develop and disseminate curricular materials in which high technologies are used to teach basic mathematical skills such as problem solving, estimation, and computer literacy. Funded by the US Department of Education, project TABS's goal is to collect and evaluate existing educational software for microcomputers and select the highest quality programs for distribution. The programs are to be field tested and distributed nationally.

Individuals or groups who have developed mathematics software for the upper elementary-school level are invited to submit their work for possible inclusion in the project. To have materials considered, send a cassette tape or floppy disk with a printout, machine documentation, and any related information to Dr Suzanne K Damarin, TABS Project, Arps Hall 202-A, 1945 N High St, Columbus OH 43210, (614) 422-1257. ■

94 February 1981 © BYTE Publications Inc

Circle 54 on Inquiry card.

Free software ($50-$120 worth). Plus a cash rebate when you buy the programmable.

B.E./

INVESTMENT

MODULE

□ $40

□ $40

□ $40

□ $40

Fluid

Dynamics

(Mm

□ $10

Lab Chemistry

r m )

D$io *

3D Graphics

f A 1

RPN SIMULATOR MODULE

□ $45

□ $10 *

□ $10

□ $10

Production/ Planning

>. ^ J

□ $10

□ $10

Electronic Engineering

<sSm

i

□ $io

Oil/Gas/ Energy

□ $10

Statistical Testing

□ $10

LD$io

2 FREE modules, 2 FREE Pakettes with a TI-59.

1 FREE module, 1 FREE Pakette

with a V^^m

TI-58C. - ^

Free software plus cash rebates.

A $10rebateon aTI-58C--$25rebateonaTI-59.

ip

The TI-58C. An exceptional value.

Up to 480 program steps or 60 memories. Plus Constant Memory™ that retains data when turned off. $130.

The TI-59. Top-of-the-Line.

Up to 960 program steps or 100 memories. Magnetic card read/ write capability. $300.

Modules turn a programmable into a dedicated calculator. Pakettes have selected programs you key in.

□ I've bought a TI-58C. Send me the one module and the one Packelte listed below, plus my $10 rebate.

□ I've bought a TI-59. Send me the two modules and two Packettes listed below, plus my $25 rebate. MODULES: PAKETTES

~P

Name

Address

ALTERNATE.

. ALTERNATE.

City

State

Zip

Send to: Texas Instruments Free Software Offer

P.O. Box 725, Oept. M, Lubbock, Texas 79491 Calculator Serial Number (from back ol unit)

Return this coupon with (1) Customer Information Card (packed with calculator), (2) Dated copy of proof of purchase between January 1,1981 — March 31,1981. Items must be postmarked by April 14,1981. Please allow 30 days lor delivery. Offer void where prohibited. Offer good in U.S.A. Tl reserves the right to substitute items. See your Tl Dealer lor complete details.

U.S. suggested retail prices. * For use with TI-59 only.

Texas Instruments

©1981 Texas Instruments Incorporated

INCORPORATED

45746A

Apple en castellano

Tercer Medio presenta su sistema administrativo

(T.M.A.) para Apple 11

Disenado de acuerdo con los principios contables aceptados en todos los pai'ses de habla hispana.

APLICACIONES COMERCIALES YCIENTIFICAS

• CONTABILIDAD GENERAL

Diario General Resumen del Diario Consulta parcial al Diario Mayor General Balance de Comprobacion Balance General Ganancias y Perdidas Catalogos de Cuentas Consultas por pantalla

• CUENTAS POR COBRAR

Catalogo de Cuentas Listado de Transacciones Antiguedad de Saldos Saldos por Veneer Relacion de Cobranzas Relacion de Pagos Estado de Cuentas Consultas varias por pantalla

INVENTARIO Y FACTURACION

CONTROL DE BANCOS

PERT/CPM

CUENTAS A PAGAR

CONTROL DE COSTO DE OBRAS

VENTAJAS DEL SISTEMA T.M.A.

Son completamentes conversacionales.

El chequeo de la informacion es instantaneo.

Los reportes impresos o por pantalla guardan

los formatos generalmente aceptados.

Estan pensados para adaptarse a cualquier

empresa.

Toda la informacion esta instantaneamente

disponible.

Precision Expandida.

Numeros de hasta ± 999.999.999.99

53

Tercer Medio

Sistema de Informacion C.A.

APARTADO DE CORREOS 62533 CARACAS 1060-A - VENEZUELA TELEX: 27.876 - CPBTH-VE. TELEFONOS: 283.60.88 - 284.74.68

'Apple es marco regisirada por APPLE COMPUTER INC

Software Review

Infinite BASIC and Infinite Business

Scott Mitchell, 346 S Taylor St, Manchester NH 03103

Infinite BASIC is a software-utility package for the Radio Shack TRS-80 sold by Racet Computes. The package has a suggested retail price of $49.95, with an optional Infinite Business package available for $29.95.

The purpose of these packages is to add extra commands to either your disk BASIC or Level II cassette system. Infinite BASIC adds eighty commands to your BASIC vocabulary, so if you thought the Level III add-on for your cassette system was a good deal, you'll consider this a steal for the same price. Level III BASIC (from Microsoft Consumer Products, Bellevue, Washington) always consumes 4 K bytes of memory, even if you use only one or two of its features in your program. Infinite BASIC lets you take only the features you want and put them on a system tape or disk file, thereby saving memory space. Also, you can place the resulting object code in memory anywhere you wish. These two features make Infinite BASIC a versatile package for both disk and tape users.

Infinite BASIC—Matrix and Strings

Infinite BASIC is the foundation of the program set.

Text continued on page 100

Name

Language

Infinite BASIC and

Z80 machine language

Infinite Business

Computer

Type

Radio Shack TRS-80

BASIC extension soft

with either disk BASIC

ware system with in

or Level II cassette

dependent application

system

modules

Documentation

Manufacturer

Printed booklets 14 by

Racet Computes

22 cm (5Vi by 8V2

702 Palmdale

inches); for Infinite

Orange CA 92665

BASIC, two booklets

(714) 637-5016

totaling 84 pages; for

Infinite Business, one

Price

booklet with 21 pages

Infinite BASIC:

$49.95; Infinite

Audience

Business: $29.95

Business, game, and

general programmers

Format

5-inch floppy disk or

tape cassette

96 February 1981 © BYTE Publications Inc

Circle 55 on Inquiry card.

But no matter what the size, they all give you increased sales, greater security, and lower costs.

Choose from the VIP (315K bytes with optional add-ons uptol.2M bytes), the Vector 2800 (2M bytes with 91 msec average access time), or the Vector 3030 (32M bytes with 34 msec average access time).

Each one gives you more disk speed and capacity than competitive models. So you can offer a less expensive system with more capacity than your competition, or one with much greater capacity for the same money.

Our multiple configurations with transportable software do not lock you into one level of system. For reliability, Vector builds industry standards into each Economy Sized Computer. Standard software and components include CP/M2® operating system, Microsoft BASIC-80? S-100 bus, 4 MHz, Z80A processor, RS-232C serial ports.

Our modular systems use common Vector 3 mainframes, boards, and printers. They save you time and money on inventory, service, staff, and training. Software transportability from one system to the next eliminates the cost of -,-. 0« j ^

rewriting or converting Economy Sized Computers

software and data. Our now Come in small,

advanced software develop- medium and large.

ment tools reduce development time dramatically. And since we have such a wide range of models, we hel p you make more sales.

All this goes to prove one thing.

That is, no matter what size system you're building, an Economy Sized Computer can be a big help.

For more information, write Vector, 31364 Via Col inas, Westlake Village, CA 91362. Or call 213/991-2302.

Economy Sized Computers

Circle 56 on inquiry card.

BYTE February 1981

97

Stack Work's

A full, extended FORTH interpreter/compiler produces COM PACT, ROM ABLE code. As fast as compiled FORTRAN, as easy to use as interactive BASIC.

SELF COMPILING

Includes every line of source necessary to recompile itself.

:: EXTENSIBLE §« Add functions at will.

CP/M* COMPATIBLE Z80or 8080 ASSEMBLER included

Single license

Supplied with extensive user manual and tutorial

$175.00

Documentation alone: $25.00

OEM's, we have a deal for you!

CP/M Formats: 8" soft sectored, 5" Northstar, 5" Micropolis Mod II, Vector MZ.TRS-80 Mod II

Please specify CPU type. Z80or8080

All Orders and General Information: SUPERSOFT ASSOCIATES P.O.BOX 1628 CHAMPAIGN, IL 61820 (217)359-2112

Technical Hot Line: (217) 359-2691 answered only when technician is available)

VfSA

SuperSoft

First in Software Technology

*CP/M registered trademark Digital Research

Listing 1: Sample string-manipulation program and run. Note that the commands are small and compact. The program initializes string AS, performs a function on it, and prints it out. After each printout of the modified string, AS is reset to its original contents and the next operation is performed. With each command that modifies AS, the modified string is stored in ]$. However, it could simply be put back into AS. The program runs quite fast.

I CLS

10 GOSUB1000

II PRINT:PRINT"A$ = (";:PRINTA$; :PRINT")"

20 J$ = &SLR$(A$,6):' LEFT ROTATION COMMAND

21 PRINT'XEFT ROTATE BY 6 = (";:PRINTJ$;:PRINT")" 30 GOSUB1000

40 J$ = &SRR$(A$,6):' RIGHT ROTATION COMMAND

50 PRINT"RIGHT ROTATE BY 6 = (";:PRINT]$;:PRINT")"

60 GOSUB 1000

70 J$ = &SLJ$(A$):'LEFT JUSTIFICATION COMMAND

80 PRINT"LEFT JUSTIFIED = (";:PRINTJ$;:PRINT")"

90 GOSUB1000

100 J$ = &SRJ$(A$):'RIGHT JUSTIFICATION COMMAND

110 PRINT"RIGHT JUSTIFIED = (";:PRINTJ$;:PRINT")"

120 GOSUB1000

130 J$ = &SLT$(A$):'LEFT TRUNCATION COMMAND

140 PRINP'LEFT TRUNCATED = (";:PRINTJ$;:PRINT")"

ISO GOSUB 1000

160 J$ = &SRT$(A$);'RIGHT TRUNCATION COMMAND

170 PRINT'RIGHT TRUNCATED = (";:PRINTJ$; :PRINT")"

180 GOSUB 1000

190 J$ = &SLS$(A$,4):' LEFT SHIFTING COMMAND

200 PRINT"LEFT SHIFTED BY 4= (";:PRINTJ$;:PRINT")"

210 GOSUB1000

220 J$ = &SRS$(A$,6):' RIGHT SHIFTING COMMAND

230 PRINT"RIGHT SHIFTED BY 6= (";:PRINTJ$;:PRINT")"

240 GOTO240

1000 A$ = " ABCD EF "

1010 RETURN

9999 END

RUN

A$ = ( ABCD EF )

LEFT ROTATE BY 6 = (D EF ABC)

RIGHT ROTATE BY 6 = ( EF ABCD) LEFT JUSTIFIED = (ABCD EF ) RIGHT JUSTIFIED = ( ABCD EF) LEFT TRUNCATED = (ABCD EF ) RIGHT TRUNCATED = ( ABCD EF) LEFTSHIFTEDBY 4 = (BCD EF ) RIGHT SHIFTED BY 6 = ( ABCD)

Listing 2: Program and run showing the packed-decimal mathematics function. The numbers must be saved into strings, then converted into packed decimal by the proper command. One may initialize precision up to 500 places; however, the more places you specify, the slower the operation will become. When the answer arrives, it is converted back to a string for printing or further normal mathematics functions. The precision of the exponent printed out in the answer is also initialized to either 10-" to 10" or I0"3276S to 10327".

10 CLS:DEFINTC

20 CLEAR2000

30 N$ = 'T':X$ = "3994949"

40 J = &BPRC(120,2):'SETS UP 120 DECIMAL PLACES PRECISION

50 ' + OR -32767 EXPONENT RANGE

60 N$ = &BCP$(N$):X$ = &BCP$(X$):'CONVERTS X$ + N$ PACKED

DECIMAL 70 A$ = &BDP$(N$,X$):' DIVIDES A$ BY X$ PACKED DECIMAL 80 N$ = &BPC$(A$):'CONVERT ANSWER TO PRINT 90 PRINT" 1/3994949= ";:PRINTN$:'PRINTS ANSWER 99 END

RUN

1A3994949 = 2.503160866384026429373691629104651899185696 7385566123622604443761359656906759009939801484324330548 3999920900116622264764D-00007

98 February 1981 © BYTE Publications Inc

wv

.Threaded Interpretive

Languages

R. G. Loeliger

Threaded languages (such as FORTH] are an exciting new class of languages. They are compact and fast, giving the speed of assembly language with the programming ease of BASIC, and combine features found in no other programming languages. An increasing number of people are using them, but few know much about how they work. Is a threaded language interpreted or compiled? How much memory overhead does it require? Just what is an "inner interpreter?" Threaded Interpretive Languages, by R. G. Loeliger, concentrates on the development of an interactive, extensible language with specific routines for the ZILOG Z80 microprocessor. With the core interpreter, assembler, and data type defining words covered in the text, it is possible to design and implement programs for almost any application imaginable. Since the language itself is highly segmented into very short routines, it is easy to design equivalent routines for different processors and produce an equivalent threaded interpretive language for other development systems. If you are interested in learning how to write better FORTH programs or you want to design your own powerful, but low-cost, threaded language specific to your needs, this book is for you.

Din i a

This and other BYTE/McGraw-Hill books are available from BYTE Books or your local computer store.

Please send

ISBN 0-07-038360-X Price $18.95

copies of Threaded Interpretive Languages

Company

Street

City

State/Province

Code

Call TOLL FREE: 800-258-5420 or Mail To:

Bill I'M 70MainSt

Peterborough, NH 03458

Check enclosed in the amount of $

_ Bill Visa G Bill Master Charge

Card No

Exp. Date

Add 75<r per book to cover postage and handling. Please remit in U.S. funds or draw on a U.S. Bank.

Text continued from page 96:

The extra commands available handle functions that, if done as a routine in standard BASIC, would take up to fifty times longer. The commands provide capabilities for matrix and string manipulation, graphics, and data compression.

There are twenty-three commands in the matrix category. Some of the many functions that they speed up are copying, scaling, solving simultaneous linear equations, matrix inversion, and operations on a matrix from constants or another matrix.

The speed of these commands is far superior to conventional BASIC. For instance, if you want to invert a 10 by 10 matrix, the command is J = &MINV(A,B,C), where A is the matrix to be inverted, B is the array where the inverted matrix is to be stored, and C is the size of the matrix to be inverted (default is the dimension of A), J is the return argument. J is 0 if a solution is found and —1 if not. The command A = &MINV(A,B,3) is certainly much faster to execute and requires less syntax than standard BASIC commands. For another example, suppose you want to multiply matrix A by matrix B. This is performed by the simple statement J = &MELM(A,B). All matrix commands are of similar format, execution time, and simplicity.

There are fourteen string-compression routines, which are extremely useful for compressing data for increased storage efficiency. However, you must know the type of data with which you are dealing and exactly what you intend to do to the data in the program. You can compress or expand in 4-, 5-, 6-, or 7-bit formats. You can use this

in random-file formats but not in sequential files (since some control characters may be in the data). You can also convert data to lowercase or uppercase and remove multiple characters.

There are fourteen string-manipulation commands provided, and they handle left and right character shifting and rotating, justifying, and truncating. You can also invert a string, sort a string (multiple-key sort), delete a substring, pack string text, and more. (See listing 1, page 98, for an example.)

The graphic commands allow drawing and erasing lines between any two coordinate points. Four commands allow scrolling of the screen up, down, left, or right. There is no wraparound feature, so scrolling up and down will result in a loss of what was at the top or bottom of the screen. These commands can best be used to improve screen presentation of data, and fast execution means little time is lost.

Other available commands include the writing of matrix data onto tape and the transfer of string and variable arguments to a subroutine in the program and back again. There are decimal-to-hexadecimal conversion commands.

Infinite Business

Infinite Business is an add-on package giving twenty commands that, among other things, control a printer, provide multiple-precision mathematics, search string arrays for matching elements, and provide hash number generation. (The package needs Infinite BASIC before it will work.)

ATTENTION ALPHA MICRO AND MPM USERS: WE HAVE THE MISSING LINK

Micro Pathways introduces the ZSIO, a four channel RS-232 interface and Real Time Clock board. Applications include Multi-User data processing and high speed telecommunications. The ZSIO board is capable of handling asychronous and sychronous byte oriented protocals such as IBM BISYNC and sychronous bit oriented protocals such as HDLC and IBM SDLC.

For Alpha Micro users it is an ideal high speed communicationsboard as well as a four channel RS-232 upgrade. MPM users can enjoy the convenience of having the Real Time Clock and four serial channels all on one board.

The ZSIO can be totally interrupt driven with no additional hardware to process restart instructions or interrupt vectors. Additional features include programmable baud rates from 75 to 19.2 k, solder less modem direction jumper areas and daisy chain capabilities to any number of boards. The ZSIO board conforms to the IEE-696 (S-100) standard bus interface. Full documentation includes users manual, theory of operation, schematic and extensive application notes.

ZSIO board complete with documentation, RS-232 cables and mounting hardware $599.00

ZSIO with Alpha Micro interface

drivers $899.00

ZSIO manual (credited upon board purchase) $ 25.00

Dealer inquiries welcome

Micro Pathways

21162 Lorain Road

Fairview Park, Ohio 44126

216-333-8864

100 February 1981 © BYTE Publications Inc

Circle 58 on inquiry card.

SYNCHRO-SOUND

The ORIGINAL Computer People

who KNOW Computers

and offer EVERYTHING you need

in Small Computer Systems

TERMINALS

ADDS Regent 25

T0^ JSSR

SYSTEM!

LEARSIEGLER

ADM3A ADM 31 ADM 42

'mP™ Printer

Printing rectl0nal

9r°memco Computer

ONLY $5?95

Hveitine ?,? Vi^o

&er& low*

SOROC Technology

IQ 120

IQ 140

HAZELTINE

Executive 80 Series

Model 20 Model 30

PRINTERS

QUME Sprint

5/45 KSR 5/55 ,

COMPUTERS

NORTHSTAR

HORIZON II HORIZON II Quad

CROMEMCO

System 3

DECwriter IV

LA 34

TELETYPE

43

MORE SPECIALS

OKIDATA

Microline 80 $570. Model SS1 for Atari 800 $695.

Integral Data Systems Model 445 Printer $695.00

Centronics 779-2 ... .775.00

Televideo Model 950 .. .1295.

Industrial Micro Systems 16 K static memory . .349.00

MANY OF OUR PRICES ARE TOO LOW TO ADVERTISE. PLEASE CALL OR WRITE

Livermore Accoustic Coupler $195.00

Centronics MicroPrinter 349.00

5"Scotch Diskette Box

8" Scotch Diskette Box

34.95 39.95

We carry a full line of Alpha-Micro Products.

We have a full staff of Programmers and Computer

Consultants to design, configure and deliver a Turnkey

Computer System to meet your specific requirements.

ENTERPRISES, INC

COMPUTER PEOPLE

193-25 Jamaica Ave., Jamaica. New York 11423 • TWX 710-582-5886

PHONE ORDERS CALL: New York 212/468-7067 Los Angeles 213/628-1808

Chicago 312/641-3010 Dallas 214/742-6090

The single board

microcomputer

that's perfect

for CP/Net"

Everything you need for a network slave is built in: Z-80 processor, 64K dynamic RAM, even the console serial port. The forthcoming expansion board will add additional ports, priority interrupt control, and IEEE S-100 bus master capability for the network master processor. And MuSYS delivers all the software support you need to take advantage of CP/NET™ and the advanced MP/M™ operating system. For your multiuser system, it's the ideal way to add stations, share common resources (peripherals, programs, data bases), and increase total throughput, while maintaining hardware isolation for each user.

Just $1,395 ea. Generous dealer and quantity discounts available. Call or write today for more details.

CP Net and MP/M are trademarks of Digital Res

Multi-user Microsystems

1451 Irvine Blvd., Suite 11, Tustin, CA 92680

(714) 730-5692. TWX: 910-595-1967

CABLE: MUSYSTSTN

Circle 59 on Inquiry card.

I found the automatic page headings and pagination to be the most helpful feature in the printer category—just define the header or footer and run the program. This feature can be turned on or off and reset within the program.

I have found that packed-decimal mathematics is very interesting to most people who have Infinite Business. With it, they can add, subtract, multiply, and divide with up to 500 significant places of precision. I would have liked to have seen some more mathematics functions here such as squares, square roots, logarithms, and other technical-mathematics functions. (See listing 2, page 98, for an example.)

Conclusions

• In checking over these packages, I saw two problems. In trying to assemble an Infinite BASIC module for use in low memory on tape, I set an upper limit of hexadecimal 7FFF and the assembler bombed out. I assume this is a result of the assembler placing its code in the same memory that I had specified during the assembly process, thus clobbering the disk operating system. It is unfortunate that the assembler cannot make the object modules in high memory and save them on tape or disk. If this were so, the object modules could then be loaded into the memory locations the user specified. As it is, the assembler will save the object code to tape, but saving to disk requires typing in a cumbersome dump command. The assembler gives everything needed to type for this dump, but it would be much easier if the user did not have to intervene (and if the disk operating system clobbering were eliminated).

• The second problem is that the setting of memory size is difficult for those BASIC programmers who are not especially familiar with machine language. The Infinite BASIC documentation spends little time with examples of how to do this with user-created object modules.

•The Infinite BASIC documentation is about as difficult to understand as the Radio Shack Level II manual. There are three manuals. Two are for Infinite BASIC—one being a general description with lots of examples, the other a definition of the command formats. The Infinite Business manual has both of these elements incorporated into one volume. All the information is there, but there are not enough examples to cover every case, so the result may be that the 100 available commands will be hard for the less experienced programmer to understand. As the command statements are fairly involved, frequent references to the manuals are necessary.

• These packages would be of great help to the more skilled business, game, and general programmer who could best understand and make use of the available power. However, in comparing these to other similar packages, almost anyone would find enough of the 100 commands useful to make it worth the price. ■

Give to the college of Your choice.

OF

Councillor Financial A.dloErlucalion inc BSQKiim Avenue New York ny i00'9

A Public Service ol This Maqa/ine & The Advernsing Council

The Perfect Fit

The Micromodem II data communications system and the Apple II* computer. What better combination to maximize the capabilities of your personal computer!

This popular direct connect modem can transmit data between an Apple II and another Apple II, a terminal, another microcomputer, minicomputer or even a large time-sharing computer anywhere in North America. The Micromodem II has unique automatic dialing and answer capabilities which further increases the communications possibilities between the Apple II and another computer or terminal.

You can send and/or receive messages or data when you are out of your office, home or out of town. Your branch business locations can communicate with each other regarding inventory and other matters over the phone. Or you can communicate with friends across the country. And you can access information utilities like the SOURCE for various business and personal applications.

The Micromodem II consists of two parts. One part includes the printed circuit board which holds the Micromodem II, ROM firmware and the serial interface. The board plugs directly into the Apple II providing all the functions of a serial interface card plus programmable auto dialing and auto answer capabilities. The on-board ROM firmware enables the Micromodem II to operate in any of three modes to perform different tasks-terminal mode, remote console and program control mode.

The other part of the Micromodem II datacomm system is a Microcoupler which connects the Micromodem board and Apple II to a telephone line. The Microcoupler gets a dial tone, dials numbers, answers the phone and hangs up when a transmission is over. There are none of the losses or distortions associated with acoustic couplers. The Microcoupler is compatible with any North American standard telephone lines and is FCC-approved for direct connection in the U.S. It works with standard dial phone service or Touch-tone service.

The Micromodem II is completely compatible with Bell 103-type modems. Full and half-duplex operating modes are available as well as speed selectable transmission rates of 110 and 300 bps.

Why not increase your Apple ll's capabilities by outfitting it with the sophisticated Micromodem II data communications system? The Micromodem II is available at retail computer stores nationwide. For the store nearest you, call or write:

Circle 60 on inquiry card.

©Hayes

Hayes Microcomputer Products Inc.

5835 Peachtree Corners East, Norcross, Georgia 30092 (404) 449-8791

TU Micromodem II is a trademark of Hayes Microcomputer Products, Inc.

'Apple II is a registered trademark of Apple Computer Inc.

The Micromodem II can also be used with the Bell & Howellcomputer.

And one that costs you a buck.

One: Buy a new TeleLink® I cartridge for your ATARI 400® or ATARI 800® computer and get one free hour of CompuServe Information Service time.

Two: Visit a Radio Shack® computer center. Most are equipped to access the CompuServe Information Service now. Log in and see what you can get. The service is compatible with any TRS-80® including the new VIDEOTEX® unit.

Three: Send $1.00 to us and we'll send you the current "menu" of services, including the sophisticated big mainframe power of MicroNET. Send $1.00, name and address to: CompuServe, Information Service Division, 5000 Arlington Centre Boulevard, Columbus, Ohio 43220.

Radio Shack, TRS-80 and Videotex are trademarks of Tandy Corporation. ATARI 400 and ATARI 800 are trademarks of ATARI, Inc.

All this is yours to command.

Access to news and entertainment databases, computer games and art, regional newspapers, newsletters, programs, languages, storage (up to 128k free!) and lots more is yours for 8V3 cents per minute (between the hours of 6 pm and 5 am weekdays and all day weekends), billed to your charge card. It's

a local phone hook-up in more than 260 U.S. cities.

CompuServe is working with 11 major regional newspapers to bring you their electronic editions, as well as the Associated Press news and sports wires.

Simple games and graphics for the beginner. And, when you're ready—try the really tough ones on MicroNET(see MicroNET service). You haven't lived

until you discover a player from Los Angeles

in your dungeon!

CompuServe is continually adding new on-line information resources. So, order our current menu and watch for new features such as an electronic encyclopedia, travel information, food preparation and gardening tips, government publication data— and much more!

MicroQuote has historical and statistical data on almost every stock, bond or option you can buy. Corporate financial information, commodity prices and financial newsletters are also available.

And, when you're ready for big-time computer action.

You need a

computer to

use all the

MicroNET

services which

put you in

command of

our big, fast

mainframe

computers.

But even with

the simplest

terminal you can send electronic mail to any other user,

use the CB simulator, and try to zap the enemy's

spaceships in real—and very fast—time. Many

networking multi-player games available.

See for yourself what a

state-of-the-art electronic information ^ service can do.Get I a demonstration at a Radio Shack® computer center or send$1.00for a current menu today.

Not 1985.

NOW!

CompuServe

Information Service Division 5000 Arlington Centre Blvd. Columbus, Ohio 43220 (614) 457-8600

Circle 61 on inquiry card.

A Pascal Library Unit for the Micromodem II

Thomas H Woteki

814 D Street NE

Washington DC 20002

(MicroNet 70220,165)

The Micromodem

The Hayes Microcomputer Products Micromodem II is a powerful combination of hardware and firmware that facilitates computer-tocomputer communication. The onboard ROM (read-only memory) contains programs for originating and answering calls (including dialing the telephone) and an ACIA (asynchronous communications interface adapter) device for parallel-to-serial conversion. In addition, the accompanying owner's manual provides a wealth of information on how to custom program the modem for such applications as repertoire dialing, modifying hardware defaults, and dumb terminal communications. All of the examples given are in BASIC.

At the time I purchased a Micromodem for my Apple II computer, Pascal software for driving it was not available. In fact, certain parts of the modem's firmware refer to locations and routines used by the old Apple monitor; these routines are accessible from BASIC but don't exist under Pascal. Having forsworn BASIC and being faced with the modem as my only non-Pascal application, I was determined to develop a suitable library of Pascal programs. With a little help from the friendly folks at Hayes Microcomputer Products (who are about to release their own Pascal

About the Author: Thomas H Woteki has a PhD in statistics and is currently developing an interactive statistics package for the Apple II. His interests include applications programming in Pascal and systems development for the Apple II.

software), and through close study of the manual, I was able to do just that.

The Library Unit

The routines are housed in an intrinsic unit dubbed "micromodem" (see listing 1). Library units are a UCSD addition to Pascal; commonly used routines can be stored in a library unit that can be called by any Pascal program. Intrinsic units have the advantage that the object code of the unit is never entered into the code file of the host program, thereby maximizing disk storage space. A slight disadvantage is that the library containing the unit must be on-line (available for access) whenever the host program is executed. I have the unit stored in my system library on the boot disk.

UCSD Pascal units consist of two major syntactical components: an "interface" block and an "implementation" block. The interface block contains the declarations for all the structures available to the calling program, just as if they were declared in the global-data segment of that program. The implementation portion contains declarations used by the unit but not available to the host, as well as definitions of all the procedures declared in the interface. All "external" procedures (the independently assembled machine-language programs used by the unit) must be declared at this point and linked in later.

Our interface block begins with the declaration of several constants which correspond to the addresses of certain locations in the modem's ROM and the Apple's memory. The

constants are appropriate to having the modem card in slot 2 on the Apple's motherboard. This is the set-up expected by the Apple's low-level I/O (input/output) drivers, the BASIC I/O Subsystem, or BIOS. If you wish to install the card in another slot you will have to modify the addresses and the BIOS accordingly.

The values "acia" and "modem" are the addresses of the ACIA and the modem control and status words, respectively. Both of these registers (actually pairs of registers) have the property that what is written to them (the control word) is not what may be read from them (the status word). Since it is important to know what was last written as the modem control word, a copy of this data is stored in location "modemcopy" in a portion of the Apple's memory.

The value "keybde" is the address of the Apple's keyboard, and "datain" is the address where characters received by the modem can be found. The value for "outa" is the address of a routine in the modem's firmware which transmits characters; this routine expects to find the characters in "dataout". Fortunately, the output routine does not reference any "old" monitor locations.

The constants "resetflag" and "selftest" correspond to two special bits in the modem control word. Setting bit 3 of the word puts the modem into the self-test mode, wherein the modem communicates with itself. Setting bit 4 prevents the ROM from automatically applying default settings to the ACIA.

The next two sets of declarations establish two variables, "br" and

106 February 1981 © BYTE Publications Inc

Circle 62 on inquiry card.

Order out of Chaos

The International Microcomputer Software Directory

At last! Your Software needs

answered by One single

comprehensive source. Essential for everyone concerned with microcomputers

The Directory

The International Microcomputer Software Directory has three sections:

1 Lists software according to specific subjects organised within seven major categories, Commerce, Education, Home, Industry, Professions, Sciences, Systems. Within the categories programs are listed with: • Name • A unique ISPN (international standard program number) • A short description

• Systems with which it is compatible (machine and operating system) • Software house • Price.

2 Lists in ISPN order (thus in Software House order) the programs with a full description of: • Features • Special requirements • Method of distribution.

3 Lists by machine (make and model), then within general categories and subjects the names and ISPNs of compatible programs.

Appendices include details of compatibility between machines and operating systems, plus a glossary of computer terms. Also included is a special consumers' guide to buying software.

Comprehensive

Every effort has been made to obtain full details from every reliable supplier of microcomputer software. International

With offices in Britain, America, and Hong Kong, we are well placed to keep in touch with developments in these major centres. We also employ a team of translators to obtain up-todate information from software centres throughout the world. Independent

The publishers have no affiliation with any of the software houses whose programs are listed in the directory. Easily-accessed

The clear cross-referencing system outlined above enables the reader to select programs by specific applications, operating systems, and price. Up-to-date

Information is stored immediately it becomes available in a large computer database which generates fully indexed and cross-referenced camera ready copy. Thus we are able to include software made available immediately prior to publication.

INTERNATmiML

SOFTWARE

Uggri^ mm

po fgfi* [p/^ mm 3>l.z.oo piusp&psi.os

Also Available

The International Microcomputer Software Directory Supplements

Available for individual machines or operating systems the Supplements contain listings of software compatible only with particular machines or operating systems. Supplements are organised as in the first two sections of the Directory section above.

_ copies of the International Microcomputer Software Directory,

Please send me

and/or copies of Software Directory Supplements, state which

Name (Block letters Please) Address

OR phone yourorderthrough now (24 hr. service) giving yourcreditcard number, and oddress (800) 525 5992

Imprint Software

420 South Howes St.

Fort Collins. CO 80521 (303) 493 2710

Circle 63 on inquiry card.

Z8000

The System X8000 MICRO-MINI,M based on the 16-bit Zilog Z8000 processor is available for Immediate delivery.

FEATURES (partial list)

• Zilog Z8000 CPU

• Intel Multibus compatible

• Unique memory management system allows up to 16 megabytes of memory

• Optional 9511 arithmetic processor

• 8-level vectored + non-maskable interrupts

• Two programable timers

• On-board monitor ROM option

• Full "Multimaster" capabilities allow multiple processors and/or DMA devices on the same bus

• Flexible and/or hard disk controller

• Powerful disk-based operating system

• Memory boards: 16K, 32K, 48K, 64K, 96K, 128K

• 15-slot backplane

• Heavy-duty switching power supply

• Industrial quality throughout

Prices start from $998. System discounts. Call for prices on complete custom systems.

SYSTEM X9020

(CPU Manual $19.95}

*4195

W The SUPER-MICRO'" READY TO RUN

SYSTEM FEATURES (partial lilt) Pascal MICROENGINE"X9000

■ 16 bil P-code CPU

• 64KbytesRAM/Full DMA

• Floppydisk controller (SSor DS)

■ Floating poinl hardware (IEEE standard)

• Syslem solt.ware with enhancements

■ 2 serial, 2 parallel ports

■ Pascal compiler,texleditors. lile manager,

CPU & memory diagnostics, symbolic Pascal debugger.

. utililie

andn

Floppy Dlih Drives (2)

• 1M combined memory

• Double density, single sided ■ Standard 8" diskettes

• 6 ms track to track

$900*

With CPU

MODEL X-920

DISPLAY/EDIT TERMINAL

•LIMITED TIMF cash price. 10%DOWN guarantees

priority. Master Charge & VISA cards accepted. System discounts

ADM3A+ plus RG graphics (512x256) ...$1995

NEC Spinwriter 5510 or5530w/trac 2895

Anadex D P-9500 printer (60dpi) 1595

X-912 CRT (less 18 function keys) 799

P-E550 CRT ("Bantam") 740

Siemens standard 8" drive (ss/sd-dd) .... 399

t—^ 312 684-3183

y«f™COMPUTEX

jijlV \ Microcomputer Syst«mi %

' ^\ V 5710 Dreiel. Chicago, It. 60637

"md", that may assume the values "low" (corresponding to 110 bps [bits per second]) and "high" (300 bps), and "answer" and "originate" respectively. Following this is a set of declarations for boolean-valued functions that report on various aspects of ACIA and modem status. The integer-valued functions "aciastatus" and "modemstatus" return a complete status report. The interface block concludes with a series of procedure declarations for setting the ACIA and modem control words and for performing such chores as dialing the phone, waiting for the other system to turn on its carrier, and sending and receiving characters. Several of these routines call external procedures declared in the implementation block. The implementation block begins with a set of declarations that facilitate direct-money accessing from Pascal. The declarations

establish the type "freeunion", a variant record, and a variable ("memory") of that type. The variable has two names (it is a free union; see Peter Grogono's Programming in Pascal, listed in the references) and will be interpreted differently depending on the name used. When referred to as "memory .addrs" it will be treated as an integer, but when referred to as "memory .pntr" it will be treated as a pointer to an array of the type "word". Thus, both the location pointed to and its contents can be manipulated from Pascal as indicated in the following fragment:

VAR x:0..255; (x takes values from 0 to 255)

integer

memory .addrs: = acia; (point to

location acia)

x: =memory.pntr[0]; (read the

Text continued on page 124

Listing 1: Library unit "micromodem" for Apple Pascal system. These routines can be called for use by any Pascal program, but they are intended to drive the Hayes Microcomputer Products Micromodem II.

c*$lprinter:*)

u$s+*)(* swapping requirci: for units *)

UNIT micromodecirINTRINSIC CODE 23 DATA 245

INTERFACE

CONST d3t3in= -16217) C JC0A7 3 3ci3= -16218.' { SC0A6 } B0dem= -1621?; £ $C0A5 3 Keabde= -16384; C JC000 3 outs*

d3t,30ut= 1912J nodeiiiCOpy=1658;

-15870)' C $C202 { $0778 C I067A

TYPE

resetfl33= 9; selftest= 16)

b3udr3te=( lowfhi^h)i

oode= ( 3nswer)0ri3in3te )J

vAR ad:mode?

br Jb3udr3te;

FUNCTION rin^inSIBOOLEAN)

FUNCTION csrrier:BOOLEAN)

FUNCTION rcvrfullIBOOLEANJ

FUNCTION trsnseffiptyrBOOLEAN)

FUNCTION 3Ci3error:B00LEAN)

FUNCTION 3Ci3ststus:iNTEGER)

FUNCTION modemststus:INTEGER)

PROCEDURE init3ci3(word!INTEGER)) PROCEDURE en3bletr3nsmit) PROCEDURE setmode(md:node)br:b3udr3te)) PROCEDURE picKuP)

Listing 1 continued on page 110

108 Febmary 1981 © BYTE Publications Inc

Circle 64 on inquiry card.

TOLL FREE 1-800-528-1418

ZENITH-HEATH Z-89 ALL-IN-ONE COMPUTER

FREE HDOS and 48K RAM included! Built-in minifloppy drive, smart terminal with 25 x 80 display!

CALL FOR PRICE!

"

LEXICON LX-11

Priced lower than Novation, lower than Livermore! New Bell 103A compatible, RS-232 compatible modem has special battery-powered option!

CALL FOR PRICE!

ATARI 800 SYSTEM

MicroWorld now offers complete systems based around the Atari 800 Personal computer... choose from a selection

of printers, disk drives, and Atari's comprehensive software library! Program recorder, modem, joysticks, and

more! CALL FOR PRICE!

OKI DATA

MICROLINE 80

MicroWorld is now featuring the Okidata Microline 80 printer, an ideal choice for small micro-system applications—business systems, personal systems, CRT hardcopy, manufacturing work stations, telecommunications applications, and distributed processing applications! The reliable M-80 is a compact printer capable of printing 80 characters per second in a 9 x 7 dot matrix format. In addition to normal upper and lowercase printing,the M-80 prints both double width characters (80 columns per line) and condensed characters, (132 columns per line) at six or eight lines per inch. Font selection, character spacing and line spacing are all under program control. Okidata warrants the M-80 print head for 200,000,000 characters or one year's normal operation! *„._-.-.

$569.00

miCRQ SHOPPER

MICROSHOPPER

New edition of the best-selling computer consumer guide! Includes more than 100 photos, dozens of product reviews ... feature articles, glossary, and

more! $10.00 post paid

DIABLO 630 RO

Letter-quality, up to 40 cps printer offers complete interchangeability between metal and plastic print wheels! Universal interface, baud rates to 9600, optional forms tractor. $2,499.00

MICROWORLD SPECIALS

Atari 400 $460.00

Atari 825 $745.00

Atari 820 $509.97

Atari 830 $149.33

Atari 850 $164.00

BASF Diskettes $ 4.25

Centronics 730 Parallel . $599.00 DEC LA-120 KSR ... Call For Price

Hazeltine 1500 $999.00

Hazeltine 1421 $810.00

ADM 3A+ $860.00

Visicalc for Atari . Call For Price Visicalc lor Apple . Call For Price Perkin Elmer Bantam CRT $499.00

SoroclQ 120 $750.00

Soroc IQ 140 Call For Price

Tl 810 BASIC $1,643.00

Tl 820 RO BASIC ... Call For Price Tl 810 With FLC and CP $1,816.00

Zenith Z-89 $2,399.00

Televideo 912B ... Call For Price Televideo 912C ... Call For Price

Prices are subject to change and offers subject to withdrawal without notice.

MOQWOnD

1425 W. 12th Place, Tempe, AZ 85281 Master Card and Visa orders welcomed!

Circle 65 on inquiry card.

64K Horizon II $26691

Don't be fooled byourlow prices.These aren'tjustany I 64K Horizon It's. They're Thoroughly rested, enhanced, and backed by fasrworraniy service. Also, we discount I the total system from game disks to hard disks. Call for I our price on your system.

Horizon II 64K Quod $3069 I

Horizon II 32K DD $2339

Horizon II 32K Quad $2689 |

PRINTERS

Okidata

Microline 80

y 5519

Epson MX-60

Centronics 737 $769

C-lroh 1540 (150 cps./132 col.) .... $899 |

Paper Tiger 460G $11491

Anadex 9500. 9501 $1299

TI-81 0 Dasic $1489

NEC 5510 $2589 j

COMPUTERS

Atari 800 $747

Zenith (Heath) Z-89 48K $2149 j

Industrial Micro 5000 DD $2499

Altos ACS-8000-5 $4995

Onyx C 8000 2 (4-user) $12995 |

TERMINALS

I P.E. Bantam (while they lost) $599

SoroclQ 120 $729

Zenith Z-19 $769

Televideo 920C $769 i

| Televideo 950C $989 |

HOW TO ORDER

Mail Older Only I 2% cash discount incl. Prices subject to change. Product I subject to avail. Az. residents add 5%. F.O.B. Scottsdale. 10-20% restocking fee for returned merchandise. I Warranties included on all products. We Export.

Scottsdale Systems

6730 E.McDowell Rood #100 t Scottsdale. Az. SS257

™ Open 6 ID 6 PM - M-Sot.

(602)941-5856

Listing 1 continued:

PROCEDURE dial( number !STRING)J

PROCEDURE waitforcarrier?

PROCEDURE hangup.*

PROCEDURE seU.odem<word:INTEGER).

PROCEDURE sendchsr?

PROCEDURE getchsKUAR ch'CHAR)!

IMPLEMENTATION

TYPE uord=PACKED ARRAYC0..13 OF 0..255J

freeunion=RECORD CASE BOOLEAN OF TRUEK addrs"INTEGER).

FALSE'Cvslue'tword)!

end;

VAR »emory*freeunionJ

FUNCTION ringing.*

C Determine whether the phone is rinsing } BEGIN

Beisor y. addr s! =M0DEM J

ringing !=meisory.v3luet[0K128»

end;

FUNCTION carrier;

( Test for presence of carrier } BEGIN

memory.addrs!=acia;

carrier!=memory.valuetCO] MOD 8'Ai

end;

FUNCTION rcvrfuli;

C ChecK if ACIA receiver register is full }

BEGIN memory.sddr s *=3 c i s! rcvrfull*=ODD( memory.vsluetCO]);

end;

FUNCTION transempta;

C ChecK if ACIA transmitter register is empty 3 BEGIN

memory.3ddrs!=3cia;

tr3nsempty!=0DD( memory.vslueKOJ DIV 2)J

end;

FUNCTION sciserror?

C ChecK for ACIA error } BEGIN

memory.sddrs!=3ci3j

sciserror !=isemory. valuet[0]>3i

end;

FUNCTION aciastatus;

C Determine ACIA status } BEGIN Bemory.addrs!=3cia; aciastatus!=memory.valuetCOIi

end;

FUNCTION modemstatus!

C Determine last value written to models 3 BEGIN

semory.addrs!=modemcopy;

Bodemstatus!=memory.valuet[03;

end;

Listing 1 continued on page 112

110 February 1981 © BYTE Publications Inc

Circle 66 on inquiry card.

from

•Dfaruiici!

♦ ♦ ♦

DISCOS

USER'S e

r

illU

DISCOVERY n._ • " V fi[

MULTIPROCESSOR

giJarnifo

o/sco

"<e*y

iftulti oou

*,*«««•«•'""•'■

THE World Class Multiprocessor

* From Guangzhou, China to Norwich. England. From Banphai. Thailand to Pasadena. California. A proven record of performance and reliability in installations throughout the World makes the DISCOVERY MULTIPROCESSOR the international choice in multiuser microcomputer systems.

WORLD CLASS SOFTWARE WORLD CLASS HARDWARE

Our Distributed Processing Operating System, dpos/2", resides in the Service Processor, establishing a CP/Mt environment for each user and managing access to the shared system resources. Multiuser facilities are provided for print spooling, for interprocessor communication and forprivate, public and shared-update files. Several processors can be employed concurrently by a single user via the enhanced batch submit facilities. And with DISCOVERY all CP/M compatible programs will execute without modification, thus protecting your software investment.

The ACE 64K Distributed Processing single board Computer, the dpc-180 " gives the DISCOVERY MULTIPROCESSOR its unique architecture. One DPC is dedicated to each user providing exclusive use of the onboard Z-80, 64K ram and serial I/O. Shared storage is provided by an expanded DPC used as the Service Processor. Additional users can be added at any time by simply inserting additional DPC's into the standard S-100 bus — up to 16 in a single chassis!

"f CP/M is a registered TM of Digital Research. Inc.

Whatever your requirements, Whatever your language. No matter how you say it — DISCOVERY is THE World Class Multiprocessor.

Se<

J

The ACE DISCOVERY MULTIPROCESSOR dedicates a complete. 64K Z-80 Distributed Processing single board Computer, the dpc-180'" to each user. An expanded DPC coordinates all of the system activities.

Multiuser mainframes with 192K ram start at under $6000. The 64K dpc-180" is priced at $1395. Immediate delivery. A complete line of standard peripherals including a 26Mbyte hard disk subsystem can be supplied on request. Dealer and OEM inquiries are invited.

Action Computer Enterprise, Inc.

55 West Del Mar Boulevard, Pasadena, California 91105 USA • Cable ACEPAS Pasadena • (213) 793-2440

NO FRILLS!

NO GIMMICKS!

JUST GREAT

DISCOUNTS

MAIL ORDER ONLY

ATARI 800

Personal Computer

System $79900

NORTHSTAR

Horizon II 32K 234900

Horizon II Quad 279900

Horizon II64K 299900

Horizon Quad 64K 339900

TELEVIDE0

912 74900

920 79900

HAZELTINE

1420 79500

1500 84900

1510 104900

1520 122900

0KIDATA

Microline80 55900

S0R0C Technology

IQ 120 69900

iq 140 99900

CR0MEMC0

System 3 569500

Z2H 799500

TELETYPE

43 94900

Acoustic Coupler 17900

DECwriter IV

LA34 97900

TEXAS INSTRUMENT

810 Multi Copy Impact Printer 149900

We'll meetor beat any advertised prices!

Most ilems in slock lor immediate delivery. Factory sealed canons Full manulacturer's guarantee.

DATA DISCOUNT CENTER

135-53 Northern Blvd.. Flushing, NY. 11354

Visa-Master Charge- N.Y S residents add SalesTax

Shipping F.O.FJ. N Y.

Phone Orders Call 212-465-6609

Listing 1 continued:

PROCEDURE initacia; C Unitialize ACIA 3 UAR dummy?INTEGER? BEGIN

senior y. addr s ?=bc i 3 i

■e(6ory.v3luetC0]!=3f

ttemory.v3luet[0j;=word;

REPEAT dummy!=0 UNTIL NOT carrier5

end;

PROCEDURE newmodemv3lue(newbits?INTEGER)?

external;

C Logical or the value last written to location modem (stored in modemcopy) with the argument? store the result in modemcopy and write it to models» 3

PROCEDURE enabletransmit;

C Turn on the modem transmitter 3 BEGIN newmodemvalue(2 )i

end;

PROCEDURE setmodeJ

C Set the mode and baud rate 3 BEGIN newmodemvalue( 4*ord( md )+ord( br ) )i

end;

PROCEDURE picKu^;

C PicK up the phone? wait for dial tone }

UAR dummy?wait?INTEGER;

BEGIN

newmodemvalue( 128 )r

C wait for dial tone3

FOR waitt=0 TO 3000 DO dummy:=0i

end;

PROCEDURE dialit(number!STRING);EXTERNAL?

C Dial the indicated numberi display the dibits as they are dialed 3

PROCEDURE dial!

C Dial the indicated number 3 BEGIN

URITE('Dialing...' )!

dialit( number )i

writeln?

end;

PROCEDURE waitforcarrierJ

C Wait for carrier after dialing 3 VAR datajwaitJINTEGER; BEGIN wait:=0>

WHILE NOT csrrier AND (waiUlOOOO) DO BEGIN

wait!=wait+i; memory.3ddrs!=datain; dat3!=memory.v3luetC0];

end; end;

PROCEDURE setmodemJ

C Urite 3 new vslue to the modem control word 3

112 February 1981 © BYTE Publications Inc

Listing 1 continued on page 114 Circle 68 on Inquiry card. *

SayAhh...

Our New graf ixPLUS™ 80-column printer opens wide for easy servicing.

Introducing the newest members of our grafixPLUS™ family—the DP-9000 Series 80/132 column printers—built on the same tradition of quality printout, solid design and low cost of ownership established by our 132/220 column DP-9500 Series.

A Case for Serviceability

Not that is comes up often, but want to get inside? Simple. Just remove a few screws and the clamshell case swings open exposing all major components. This easy access plus built-in self-test and minimum component count yields an MTTR of onehalf hour. The 9-wire print head replacement's even simpler... two screws and it's out. Without opening the case. And without a service call.

Performance Plus

The DP-9000 Series prints the full ASCII 96 character set, including descenders and underlining, bidirectionally, at up to 200 CPS. Number of columns can go up to 80 or 132, depending on character density—switch or data source selectable from 10 to 16.7 characters per inch. And all characters can be printed double width. The print head produces . razor-sharp characters and high-density graphics with dot resolutions of 72X75 dots/inch under direct data source control.

Interface Flexibility

The three ASCII compatible interfaces (parallel, RS-232-C and current loop) are standard, so connecting your computer is usually a matter of plug

it-in and print. Also standard are: a sophisticated communications interface for printer control and full point-to-point communications, DEC PROTOCOL, and a 700 character FIFO buffer. An additional 2K buffer is optional. When you're ready for a printer (or several thousand), look into the grafixPLUS DP-9000 Series from Anadex—you'll find an open and shut case for quality. Contact us today for details, discounts and demonstrations.

nnadex

k ...the plus in printers

...close please

SALES OFFICES: San Jose, CA (408) 247-3933

Fullerton, CA (714) 871-0501 •Wakefield, MA (617)245-9160 • Austin, TX (512) 32V -„

ANADEX, INC. • 9825 DeSoto Avenue • Chatsworth, California 91311 U.S.A. • Telephone; (213) 998

ANADEX, LTD. • Dorna House, Guildford Road • West End, Woking, Surrey GU249PW, England • Tel: Chobham(09905)6333 • Telex: 858762 ANADEX <

CROSS-COMPILE

FORTH !

Nautilus Systems' Forth Cross-compiler is now in use by individuals, universities, and major companies around the world.

OSES:

• To produce a modified or tailored version of Forth on a host computer.

• To produce Forth systems for computers that have none.

• To produce applications that use the minimum required nucleus code.

• To do all the above in a RDM/RAM environment.

FEATURES:

Written entirely in high level fig-Forth.

Automatic forward reference to any word or label.

Cross-compiles to any location in the host for any

base address in the target.

Cross-canpiles to any screen in the host for any

base address in the target.

Cross-canpiles vocabularies.

Can produce headerless code.

Can produce ramble code.

Load map that shows address, type of symbol and

name. The map appears in readable column format, and

page width and length are selectable.

A comprehensive list of undefined symbols is

produced showing undefined CFAs, DOES? pointers,

labels and words on a vocabulary-by-vocabulary

basis.

MACHINE READABLE VERSIONS FOR THE FOLLOWING SYSTEMS:

TRS-80 NORTHSTAR

APPLE CP/M

H-89 LSI-11

Each includes an executable version of fig-FORTH model 1.0, Cross-canpiler, cross-canpilable source, utilities, and documentation. (This program is not intended for newcaners to FORTH)

Price $150.00 (Includes shipping). Calif, residents please add sales tax.

NAUTILUS SYSTEMS

P.O. BOX 1098 SANTA CRUZ, CA. 95061

FOR THE SERIOUS FORTH USER

TRS-80 is a trademark of Radio Shack, a division of Tandy Corp.

APPLE is a trademark of Apple Computers Inc.

CP/M is a trademark of Digital Research.

LSI-11 is a trademark of Digital Equiptment Corp.

COPYRIGHT ° 1981 NAUTILUS SYSTEMS

HOST — TARGET

off the modem 3

Listing 1 continued:

BEGIN •emor y. addr 5!=modemcop y > »enora.v3luetC0!It=0; newniodemvalue( word )>

end;

PROCEDURE hangup;

C Hang up the phone? turn BEGIN seUiodent 0 )J

end;

PROCEDURE sndcharJ EXTERNAL;

C Get a character from the Keaboard> transfer it to the modem output location dataout» and transmit the character via the modem routine located at ouLs } PROCEDURE sendcharJ BEGIN sndchar;

end;

FUNCTION StchartCHARJEXTERNAL;

C Fetch the character stored in the inodea input location datain and send it to the screen. Pass the character as a function result. 3 PROCEDURE Setchar; BEGIN ch! = 3tchar J

end;

BEGIN setitiodem( resetflaS); END.

Listing 2: The assembly-language programs called in the implementation block of listing 1. These low-level utility routines are stored as part of a file called NAT1VECODE in a library unit, and may be accessed from any Pascal program.

I I 'I I "l I V i I i i I '( I 11 I 1 i I I

these routines are stored in the system library!

f'0ke( value, addrs: integer)!

f'eek( addrsi integer )t integer?

call(addrs: integer)!

dialit(numeer:string);

neumodehvaluef uordtinteger);

sndchar;

gtchar;

THOMAS H.U0TEKI LAST UPDATE HAY 1980

.MACRO pop pla

3TA %1

PLA

STA £111

Listing 2 continued on page 116

Hi February 1981 © BYTE Publications Ire

Circle 69 on inquiry card.

Circle 70 on inquiry card.

BYTE February 1981 115

TOLL FREE OUTSIDE CAL 1(800) 421-0347

ocommodore

Call for latest price on:

8000

iness computer CBM 2001 3usiness computer CBM 2001 PET

CBM 2022 Printer CBM 2023 Printer CBM2040 Dual Drive Floppy Disk CBM 8050 Dual Drive Floppy Disk

apple II & II plus

Here is THE computer from NEC. Centronics and RS232 interfaces are standard. Up to 64 K (RAM). SEND FOR PRICE AND INFO., OR CALL TOLL FREE

16K-Call 32K-Call 48K-Call toll Iree

monitors

9" Black and white. Only $185.

Also available In Sanyo

12" Black and white 15" Black and white.

TRS-80

All TRS-80 Compatible Hardware and Software. Call us and tell uswhal you need! y\^ ao is a lr;»Uniark til" Tiimlv (irfi

print wheels and thimbles

Huge selection for Qume, Diablo, NEC. Plastic or metal. Call 1-800-421-0347.

illATARI 825 yiK Printer..$799

apple cards

m>

Hi-Speed Serial Interface Communications Interface Parallel Prtnter Interface Centronics Printer Interface Hobby/Prototype Integer Basic Firmware Applesoft Firmware

Call Call Call Call Call Call

NEC

Letter quality high speed printer, bidirectional, high resolution plotting, graphics.

RO with Tractor Feed $2865. KSR with Tractor Feed $2995.

Paper Tiger (1P440) $949. With Graphics Anadex DP9500 $1449 DP8000 $849. Epson MX 80 $645.

CALL FOR EE CATALOG

Everything that 400 has plus Basic Language Cartridge. 16K memory (expandable to 4BK) Only $798.

4^ Bonus 8K Memory Module good till

t" 12/31/80.

Atari Program Recorder. Only $68.95

Atari Expansion Memory 8K $89.95 16K $159.

% apple II inventory control system

The first truly professional system that can tackle up to 8,100 items, transaction register/audit trail, inventory status report, re-order report, keeps track of purchase orders automatically, will handle multiple departments or divisions, fast data retrieval. Minimum hardware requirements: Apple II Plus with 48K. one disk drive and 80 column printer. Available also for the new DOS 3.3.

j[ysan diskettes

8" (Box of 10)

3740/1 sgl sibe/sgl density $4.50 on. 3740/1D sgl side/dbl den

$6.65 •■ 5" (Box ol 5) 104/1 soft sector. 107/1 10 sectors, 105/1 16sectors $4.50 M.

The HP-85 is a powerful BASIC language computer alete with keyboard, CRT display, printer, and tape drive -all in one compact unit.

I CalH

Prices subject to change without notice. Please allow ample time tor checks t o clear. Please add 2% for shipping and handling. California residents please add 6% sales tax. Sorry, no COD.

£&

m

Micromodem 100 Ca Micromodem II OnlyS325

In California Call (213) 371-1660

/MICRO

BUSINESS WORLD

15818 Hawthorne Blvd., Lawndale. CA 90260

Immediate response to your orders

U.S. and International Dealer] uiries Invited.

Listing 2 continued:

.ENDM

•MACRO PUSH

LDA n+i

FHA

LDA XI PHA .ENDM

.GLOBAL EQUATES

PASCAL .EQU 00

PASCALHI .EQU 01

BI0SIN ' .EQU 0COS3

PICSOUT .EQU 0C08B

CONCHECK .EQU 0D681

VIIiQUT .EQU 0D7E7

.PR0C POKE.2 i2 PARAMETER WORDS

?

5PROCEDURE'. VALUE.ADDRS: INTEGER)

i effect:

V

i VALUE IS STORED AT ADDRS

ADDRS .EQU 02

ADDRSHI .EQU 03

FOP PASCAL

LDY *00

POP ADDRS

."INITIALIZE Y-REG

.SAVE ADDRESS ,'ARGUEMENT

PL A ,'LSB OF VALUE

STA 8ADDRS.Y ,'STORE VALUE AT

.ADDRS F1A ."DISCARD MSB VALUE

PUSH PASCAL RTS

,'BACK TO PASCAL

.FUNC PEEK.l ,'1 PARAMETER WORD

FUNCTION PEEK(ADDRSI INTEGER )!INTEGER 5

; effect:

5

5 THE CONTENTS OF ADDRS ARE

i RETURNED BY PEEK

ADDRS

.EQU 02

ADDRSHI

•EQU 03

POP PASCAL

PLA

PLA

PLA

PLA

F0F ADDRS

.DISCARD 4 BYTES .OF STACK BIAS fASSOCIATED WITH FUNCTIONS

.SAVE ADDRESS TO iPEEK

Listing 2 continued on page 118

116 February 1981 © BYTE Publications Inc

Circle 71 on inquiry card.

The best news since CP M... customizable full screen editing

As a serious computer user you spend much of your time editing, whether it be for program development or word processing. Make the best use of your time with the help of VEDIT, an exceptionally fast and easy to use full screen editor. VEDIT is a highly refined and proven editor which is easy enough for novices to learn and use. Yet its unequalled set of features also makes it the choice of computer professionals. And because VEDIT is user customizable, it adapts to your keyboard, hardware, applications and preferences.

In VEDIT, the screen continuously displays the region of the file being edited, a status line and cursor. Changes are made by first moving the cursor to the text you wish to change. You can then overtype, insert any amount of new text or hit a function key. These changes are immediately reflected on the screen and become the changes to the file.

VEDIT has the features you need, including searching, file handling, text move and macros, plus it has many special features. Like an 'UNDO' key which undoes the changes you mistakenly made to a screen line. And a mode which allows a programmer to enter all text in lower case and let VEDIT convert the labels, opcodes and operands, but not the comments, to upper case. The screen writing is almost instantaneous on a memory mapped display or can use your CRT terminal's editing capabilities. Disk access is very fast too, and VEDIT uses less than 12K of memory. The extensive 70 page, clearly written manual has sections for both the beginning and experienced user.

Totally User Customizable

Included is a setup program which allows you to easily customize many parameters in VEDIT, including

the keyboard layout for all cursor and function keys, screen size (up to 70 lines, 200 columns), default tab positions, scrolling methods and much more. This setup program requires no programming knowledge or 'patches', but simply prompts you to press a key or enter a parameter.

The CRT version supports all terminals by allowing you to select during setup which terminal VEDIT will run on. Features such as line insert and delete, reverse scroll and reverse video are used on 'smart' terminals. Special function keys on terminals such as the HI9, Televideo 920C and IBM 3101, and keyboards producing 8 bit codes or escape sequences are also supported.

New Features and Support

The new release includes disk write error recovery, indent and undent keys for structured programming, and the ability to insert a specified line range of another file at the cursor position. Versions for MP/M and the Apple 11R SoftCardRare now also available.

Ordering

Specify the CRT version, your video board or microcomputer, the 8080/Z80 or Z80 code version, and disk format required.

Standard Package: Disk and manual $110

Manual: Price refunded with software purchase 15

VISA and MASTER CARD Welcomed. Attractive Dealer Terms.

CP/M and MP/M are registered trademarks of Digital Research, Inc. Apple 11 is a registered trademark of Apple Computer, Inc. SoftCard is a trademark of Microsoft.

North Star • Heath H8/H89 • SuperBrain • Apple 11 SoftCard • Sorcerer • TRS-80 Model I TRS-80 Model 11 • MP/M • Most other CP/MRSystems with CRT or Memory Mapped Displays

CompuView Products Inc.

618 Louise, Ann Arbor, Michigan 48103 • Telephone (313) 996-1299

Circle 72 on inquiry card.

BYTE February 1981

117

OS-9™ MULTIPROGRAMMING OPERATING SYSTEM

/•true multitasking, real time operating system for / M timesharing, software development, database, L m process control, and other general applications. This versatile OS runs on almost any 6809-based computer.

■ UNIX™ -like file system with hierarchical directories, byte-addressable random-access files, and full file security. Versatile, easy-to-use input/output system is hardware independent and expandable.

■ Powerful "shell" command interpreter features: I/O redirection, multiple job stream processing, and more. Includes a complete set of utility commands.

■ OS-9 Level Two uses hardware memory management and can address over one megabyte of memory. Also includes pipes and filters for inter-process data transfers.

■ OS-9 Level One runs on systems without memory management hardware having up to 56K memory. DOS-9 Level Two $495* □ Level One $195

BASIC09™ PROGRAMMING LANGUAGE SYSTEM

Extended BASIC language compiler/interpreter with integrated text editor and debug package. Runs standard BASIC programs or minimally-modified PASCAL programs.

■ Permits multiple named program modules having local variables and identifiers. Modules are reentrant, position independent and ROMable.

■ Additional control statements for structured programming: IF ... THEN ... ELSE, FOR ... NEXT, REPEAT . .. UNTIL, WHILE ... DO, LOOP . . . ENDLOOP, EX1T1F . . . ENDEXIT.

■ Allows user-defined data types and complex data structures. Five built-in data types: byte, integer,

9 digit floating-point, string and boolean.

■ Runs under OS-9'" Level One or Level Two. D$195*

OTHER OS-9™ FAMILY SOFTWARE

■ Stylograph1" Screen-Oriented Word Processor

■ Interactive Assembler ■ Macro Text Editor

■ Interactive Debugger

BASIC09 and OS-9 are trademarks of Microware® and Motorola. UMX is a trademark of Bell Laboratories.* Most software is available on ROM or diskette in versions for many popular 6809 computers. Contact Microware® for specific availability.

MICROWARG®

Microware Systems Corp., Dept. B2

5835 Grand Avenue, Des Moines, Iowa 50304

(515) 279-8844 • TWX 910-520-2535

Listing 2 continued:

LDA *00

.INITIALIZE

TftY

JY-REG

PHA

.PUSH MSB OF

JRETURNED VALUE*.

JZER0

LDA 8ADDRS.Y

.LOAD A WITH LSB

5 OF RETURN VALUE

PHA

.PUSH ON STACK

PUSH PASCAL

RTS

J BACK TO PASCAL

.PR0C CALL.l

! 1 PARAMETER WORD

PROCEDURE CALLtADDRS)?

EFFECT t

CALLS THE ROUTINE LOCATED AT ADDRS AND RETURNS TO PASCAL

USES A FORM OF INDIRECT ADDRESSING SUGGESTED BY KENNETH SKIER IN THE JAN 19S0 OF BYTE. P. 118.:

A JSR INSTRUCTION FOLLOWED BY "ADDRS" ARE LOADED INTO CONSECUTIVE LOCATIONS

^BEGINNING AT LOCATION "JUMP". CALL THEN JEXECUTES A JSR TO THAT LOCATION THEREBY JTRANSFERRING CONTROL TO THE ROUTINE "LOCATED AT "ADDRS". 5

JUHEN THE RTS IN THE DESTINATION ROUTINE "IS ENCOUNTERED. CONTROL IS RETURNED TO ^LOCATION "DONE". THEN TO THE MAIN BODY 50F CALL, THEN TO PASCAL.

JUMP

.EQU 02

ADDRS

.EQU 03

ADDRSHI

.EQU 04

DONE

•EQU 05

POP PASCAL

LDA *20

STA JUHP

LDA *60

STA DONE

POP ADDRS 5SAVES ADDRESS OF

J DESTINATION ROU

TINE

JSR JUHP

PUSH PASCAL

RTS

,PR0C DIALIT.l » » A PROCEDURE TO DIAL THE PHONE USING

Listing 2 continued on page 120

118 February 1981 © BYTE Publications Inc

Circle 73 on inquiry card.

MULTIUSER

III

iiimmimim

L

COMPUTER

ON S- 1 DO BUS DESIGNEO TO SATISFY A WIDE VARIETY OF '

APPLICATIONS.

STANDARD FEATURES

INCLUDE: CP/M . OPERATING SYSTEM, E4K EXPANDABLE, BANKSEMEMORY,4MHZ ZSDA CPU WITH 4 SERIAL AND 3 PARALLEL PORTS, RELIABLE B" FLOPPY DISK DRIVES IN A STURDY ALL METAL CABINET.

$ 49DO

MP M OPTIONAL.

;? - tii m» u registered trade marks oh t gum ke

fpl

r~

WM

. .O.BOX 1847 SAN DIEGO, CA. 32112 333 MISSION CENTER RD SAN DIEGO.CA. 321QB

(714] 296-9183

Listing 2 continued: THE D.C. HAYES MICROMDEM II.

THIS ROUTINE IS CALLED BY THE PROCEDURE

DIAL(NUMBERISTRING)

IN THE LIBRARY UNIT MICROMDEM.

THIS ROUTIINE ASSUMES THE MICROMDEM IS IN SLOT 2 ON THE MOTHER BOARD. IT SHARES "MODEMCOPY". WHICH CONTAINS A COPY OF THE MODEM CONTROL WORD* WITH THE LIBRARY UNIT.

hODEh .EQU OCOA5 MODEMCOPY.EQU 067A

WAIT61 .EQU 9?

UAIT3? .EQU 7A

LOCATION .EQU 02

LENGTH .EQU 04

HANGUP .EQU 06

PICKUP .EQU 07

."SAVE THE PASCAL RETURN ADDRESS POP PASCAL

.POP THE HEhORY ADDRESS OF THE (TELEPHONE NUMBER POP LOCATION

.'INITIALIZE LOCATIONS HANGUP

MODEL PC-10: Finger Controlled

Desoldering Systems

REMOVE ANY COMPONENT

FROM ANY PCB

... QUICKLY AND SAFELY

MODEL PC-20: Footpedal Controlled

STANDARD SYSTEM FEATURES

■ Lightweight and Portable

■ Internal Vacuum Pump

■ Sodr-X-Tractor Handpiece

■ Variable Temperature Control

INCORPORATED

9893 Brewers Court ■ Laurel, Md. 20810 ■ phone (301) 490-9860

(AND PICKUP FOR

PROPER

DIALING

LDA

MODEMCOPY

AND

♦7F

STA

HANGUP

LDA

MODEMCOPY

ORA

#80

STA

PICKUP

i REMEMBER HOW MANY

DIGITS IN

;the

TELEPHONE

NUMBER

LDY

♦00

LDA

0LOCATION.Y

STA

LENGTH

(INITIALIZE TO

GET

THE

FIRST

(DIGIT

LDY

♦ 01

NXTDIGIT TYA

PHA

(SAVE DIGIT

NUMBER

ON STACI

LDA BIOSIN iSWTICH TO BIOS

LDA SLOCATION.Y (DISPLAY DIGIT

JSR VIDOUT >0N CONSOLE

LDA BIOSOUT .'BACK TO PASCAL

PLA (RECOVER DIGIT NUMBER

TAY

LDA @LOCATION,Y (GET DIGIT AGAIN

START

PULSE

(CONVERT DIGIT FROM CHARATER FORM

SEC

SBC

*30

BNE

START

LDA

*0A (IN CASE

DIGIT

IS 0

(INITIALIZE X TO

COUNT

PULSES

TAX

(DIAL THE DIGIT

LDA

HANGUP

STA

MODEM

LDA

♦UAIT61

JSR

WAIT

LDA

PICKUP

STA

MODEM

LDA

♦WAIT39

JSR

WAIT

DEX

BNE

PULSE

(WHEN DONE WITH A DIGIT CHECK (TO SEE IF DONE WITH NUMBER

CPY

LENGTH

BEQ

DONE

(IF

NOT. WAIT A

WHILE

THEN

GET

(THE

NEXT DIGIT

JSR

LONGWAIT

INY

BPL

NXTDIGIT

DONE

PUSr

1 PASCAL

RTS

LONGWAIT

LDX

♦05

AGAIN

LDA JSR DEX BNE RTS

♦OFF WAIT

AGAIN

Listing 2 continued on page 122

120 February 1981 © BYTE Publications lnc

Circle 75 on Inquiry card.

WHY GROWING CONCERNS PICK OUR FLOPPY BASED SYSTEMS

Growing concerns require fresh ideas. Ideas that stimulate growth. Ideas that manage growth. Ideas that are designed to grow with the business.

Altos Computer Systems, a world leader in single board microcomputer technology, cultivates these ideas and delivers them in an attractive assortment of economical floppy disk based systems.

Take the compact, portable ACS8000-2 family, for example. This dual floppy system with 64 KBytes of RAM is perfect for inexpensive work station applications such as business accounting and word processing.

Altos' versatile and upgradable ACS8000-5 system is the solution for growing storage capacities. Simply add chips to Altos' reliable, fully socketed single board computer to upgrade to any of Altos' ACS8000-6 hard disk or multi-user systems. Choose up to 208 KBytes of onboard RAM storage which can be accessed in 48 KByte banks—one bank for each of four users. Like all Altos family members, the ACS8000-5 has full asynchronous, bisynchronous, and networking communications capabilities.

All Altos systems are packaged with the most select features, such as the single board Z80A* CPU,

quality Shugart drives, and optional DMA and floating point processors. And every Altos system must endure extensive reliability testing including 48 hours of in-process burn-ins.

Altos supports three industry standard operating systems: single/ multi-user CP/M,** OASIS} and Altos' proprietary AMEX.'" Seven high level programming languages are offered which are CP/M or AMEX compatible.

Weed through the microcomputer system alternatives. No matter what your application, you'll pick Altos.

For specific details about pricing or performance, call or write-. Altos Computer Systems, 2360 Bering Drive, San Jose, CA, 95131, (408) 946-6700, Telex 171562 ALTOS SNJ.

1-4 Users

System Software

Floppy Disks: .5Mb-2Mb And Cartridge Tape Back-Up

Packed with Fresh Ideas

COMPUTER SYSTEMS

*ZB0A is a registered trademark of Zilog. Inc.

'CP/M is a registered trademark of Digital Research. Inc. 10ASIS is a registered trademark of Phase One Systems. Inc. © I980 Altos Computer Systems

Circle 76 on inquiry card.

BVTE February 1981

121

Listing 2 continued:

WAIT

SEC

WAIT2

PHA

UAIT3

SBC #01

BNE UAIT3

PLA

SBC #01

BNE UAIT2

RTS

;bits to be set and update

(MODEM

PLA

ORA MODEMCOPY

STA MODEMCOPY

STA MODEM

PLA (DISCARD MSB OF JNEUBITS

.PROC NEWM0DEMVALUE,1

A PROCEDURE TO CHANGE THE CONTENTS OF LOCATION «0A5 UHICH IS THE (SLOT 2) LOCATION OF THE MICROMODEM CONTROL WORD. THIS IS A ROUTINE WRITTEN ESPECIALLY FOR USE BY THE LIBRARY UNIT MICROMODEM.

THE ROUTINE LOGOCAL ORS ITS ARGUMENT WITH THE CONTENTS OF MODEMCOPY. J067A, SAVES THE RESULT IN MODEMCOPY AND WRITES IT TO MODEM. *C0A5.

MODEMCOPY ,EQU 067A MODEM .EQU 0C0A5

POP PASCAL

iPULL THE VALUE OF THE NEW

TERMINALS FROM TRANSNET

PURCHASE PLAN • 12-24 MONTH FULL OWNERSHIP PLAN • 36 MONTH LEASE PLAN

PURCHASE PER MONTH

DESCRIPTION PRICE 12M0S 24MDS 36MDS

LA36 DECwriter II $1,695 S162 S 90 S 61

LA34 DECwriter IV 1,095 105 58 40

LA34 DECwriter IV Forms Ctrl. .. 1,295 124 68 46

LA120 DECwriler III KSR 2,495 239 140 90

LA120 DECwriler III RD 2.295 220 122 83

VTIOOCRTDECscope 1,895 182 102 69

VT132 CRT DECscope 2,295 220 122 83

TI745 Portable Terminal 1,595 153 85 58

TI765 Bubble Memory Terminal . 2,595 249 138 93

TI783 Portable KSR, 120 CPS ... 1,745 167 93 63

TI785 Portable KSR, 120 CPS ... 2,395 230 128 86

TI787 Portable KSR, 120CPS... 2,845 273 152 102

TI810 ROPrinler 1,895 182 102 69

TI820 KSR Printer 2,195 211 117 80

730 Desk Top Printer 715 69 39 26

737 W/P Desk Top Printer 895 86 48 32

704 RS232-C Printer 1,795 172 96 65

6081 High Speed Band Printer .. 5.495 527 293 198

DT80/1 CRTTerminal 1,795 172 96 65

DT80/1L15'Screen CRT 2,295 220 122 83

DT80/5APLCRT 2,095 200 112 75

DT80/5LAPL15';CRT 2.595 249 138 94

ADM3A CRTTerminal 875 84 47 32

ADM31CRT Terminal 1,450 139 78 53

AOM42 CRT Terminal 2,195 211 117 79

1420 CRT Terminal 945 91 51 34

1500 CRTTerminal 1,095 105 58 40

1552 CRT Terminal 1,295 125 70 48

'.nm- _ Letter Duality KSR, 55 CPS 3,395 326 181 123

' iiJi'jl- ■ Letter Duality RO, 55 CPS 2,895 278 154 104

2621A CRT Terminal 1,495 144 80 54

2621PCRTTerminal 2,650 255 142 96

DEC

TEXAS INSTRUMENTS

CENTRONICS

DATAMEDIA

LEAR SIEGLER

HAZELTINE

HEWLETT PACKARD

FULL OWNERSHIP AFTER 12 OR 24 MONTHS • 10% PURCHASE OPTION AFTER 36 MONTHS

ACCESSORIES AND PERIPHERAL EQUIPMENT

ACOUSTIC COUPLERS • MODEMS ■ THERMAL PAPER ■ RIBBONS • INTERFACE MODULES • FLOPPY DISK UNITS

OTHER POPULAR TERMINALS, COMPUTER PERIPHERALS AND COMPUTERS AVAILABLE.

RA NSiXETcorporation

1945 ROUTE 22 • UNION, N.J. 07083 • (201) 688-7800

TWX 710-985-5485

.BACK TO PASCAL PUSH PASCAL RTS

.PROC SNDCHAR

i APROCEDURE TO OUTPUT ONE CHARACTER

i THROUGH THE MICROMODEM LOCATED IN

> SLOT 2.

i

r ROUTINE IS CALLED FROM THE LIBRARY

5 UNIT MICROMODEM.

RPTR

.EQU

0BF18

WPTR

.EQU

0BF19

CONBUF

.EQU

03B1

BUMP

.EQU

0D72C

DATAOUT

• EQU

0778

OUTA

.EQU

0C202

LDA

BIOSIN

JSR

CONCHECK

LDX

RPTR

CPX

WPTR

BEG

HOME

JSR

BUMP

STX

RPTR

LDA

CONBUF»X

STA

DATAOUT

JSR

OUTA

HOME

LDA RTS

BIOSOUT

.FUNC GTCHAR

A ROUTINE TO GET ONE CHARACTER FROM THE MICROMODEM DATA INPUT LOCATION DATAIN. THE ROUTINE ASSUMES THE RECEIVER REGISTER IS FULL.

AFTER FETCHING THE CHARACTER THE ROUTINE OUTPUTS IT TO THE CONSOLE SCREEN AND RETURNS THE VALUE TO THE CALLING PROGRAM AS A FUNCTION RESULT.

THIS ROUTINE IS PART OF THE LIBRARY UNIT MICROMODEM.

DATAIN

.EQU 0COA7 POP PASCAL

Listing 2 continued on page 124

122 February 1981 © BYTE Publications Inc

Circle 77 on inquiry card.

Moke

Vour

Dreams

Come True

Imagine sitting down ot Your computer system and developing that specialized application you've always dreamed about — with absolutely no programming!

Now you can with PRISM™ — the First Data Base Management System that provides the Total Solution to your information management needs. UJith PRISM™, you can have your application up and running in a matter of minutes not months.

PRISM requires CP/M and C6P.SIC. (CP/M is a registered trademark of Digital Research. CSRSIC is a trademark of Complier Systems.)

PRISM's flexibility and ease of use are combined with its full spectrum of features and capabilities to make it the ideal DBMS for a wide range of business applications. Mailing Lists, Patient Records, Real (Estate Listings, and Client Billings are just a few of the possibilities. And PRISM™ provides the quality, performance, and affordability you have come to expect from MAG software products.

To find out how your dreams can

become realities, see your PRISM™

dealer today.

Micro Applications Group, 7300 Caldus

Avenue, Van Nuys, California 91406,

(213)881-8076.

PRisnn

TM

"The Total Solution" fUlMB

£ MAG 1980

Circle 78 on inquiry card.

BYTE February 19B1 123

Text continued from page 108:

status of the acia)

memory.pntr[0]:=x; (write the

acia control word)

This technique is used in the code for several of the listed routines. Implementation of the technique may be machine dependent. The alternative is to link externally assembled machine-language programs to perform the work of BASIC'S PEEK and POKE. Such programs are illustrated below.

The procedure "initacia" performs initialization of the ACIA by setting it up for characters of the length specified by the parameter value. It then waits for a no-carrier-detected signal before returning.

Several of the procedures call the external procedure "newmodemvalue" which is used to set selected bits in the modem control word to logical 1 without affecting the status of any other bits. By contrast, "setmodem" sets all bits (except the selected ones) to logical 0.

Procedure "waitforcarrier" waits a period of time to detect a carrier after dialing the phone. Unloading the location "datain" in the WHILE...DO loop is necessary to satisfy the ACIA, as suggested on pages 38 and 39 of the owner's manual.

The procedures "sendchar" and "getchar" are Pascal hosts for calling the external procedures "sndchar" and "gtchar" which are the workhorses for simple modem I/O. "Getchar" passes the character it gets to the calling program via the variable parameter "ch" in case the user wishes to process "ch" further (say, by sending it to the system printer). I have done this to retain printed copy of terminal sessions.

The statement "setmodem (resetflag);" in the body of the unit will be executed as an initialization step when the host program is executed. Setting the reset flag informs the ACIA that default initializations are not to be applied when the ACIA is first called for input or output.

The External Procedures

The assembly-language programs called in the implementation block of the unit (see listing 2) are part of a file called NATIVECODE. I have stored these and other low-level utility routines, such as the PEEK and POKE routines, in a library unit. Therefore they can be called from any of my

Listing 2 continued

I;

PLA

(DISCARD 4

BYTES OF FUNC

FLA

;tion BIAS

PLA

PLA

LDA

BIOSIN

JSR

CONCHECK

;get

' CHARACTER

AND

,'PUSH FUNCTION

RESULT

LDA

♦00

PHA

LDA

DATAIN

PHA

fOUTPUT TO CONSOLE

JSR

VIDOUT

LDA

BI0S0UT

PUSH

PASCAL

RTS

.END

Listing 3: The Pascal program called "fullduplex". This program makes use of the compiled code of the unit, linked with the assembled code of NATIVECODE.

PROGRAM full duplex;

USES Oiicromodenij

FUNCTION peeKC Iocs t ion! INTEGER it INTEGER,' EXTERNAL?

PROCEDURE dialupj VAR number'STRING) wordHNTEGER;

PROCEDURE sSetaeiacntrKVAR

word

I INTEGER)!

BEGIN

REPEAT

P33e( output )>

3oto>;y( 0 r 3 )»

wri teln( ' Select

the ACIA

control word!' ) >

writelnfwriteln

1

wntelnC'CHAR

PARITY :

3T0P

CONTROL-' )»

writeln< 'LENGTH

BIT

BITS

WORD ' )»

■. * , /

- — ' i:

uritelnC' 7

EVEN

4

r);

uritelnC' 7

ODD

-1

5' );

uritelnC' 7

EVEN

1

9');

uritelnC' 7

ODD

1

13' ),'

uritelnC' 8

NONE

0

17' j;

writelnC ' 8

NONE

1

2i');

uritelnC 8

EVEN

1

25';;

uritelnC' 8

ODD

1

29');

writeln)

unteC 'ACIA con

trol word

~"*V

>;

readlnC word )>

UNTIL word IN CI

,5,9,13,1

7,21,25,29];

END) C Setcntrlword 3

BEGIN C dislup 3 setroodenK resetf ls£);

Listing 3 continued on page 126

124 February 1981 © BYTE Publications Inc

GOmPUTER WAREHOUSE

CALL TOLL FREE 1-800-528-1054

ATARI

800 (16K) S775

400 S440

810 Disk Drive $520

825 Printer $750

850 Interface $160

16K Memory $110

410 Recorder $ 70

830 Modern $145

Star Raiders $ 45

Software From $ 10

Special 32K 800 System

800 w/32K, recorder

star raiders, joystick $970

MODEMS

Lexicon LEX-II $115

Novation

CAT $ 150

D-CAT $160

MONITORS

APF-9" Monitor $123

Sanyo - 9" Monitor $147

VIDEO TERMINALS

Hazeltine

1500 $848

1420 $795

Soroc

iq 120 $693

IQ 140 $1099

Televideo

912 B $724

912 C $724

920 B $773

920 C $773

Zenith - Z - 19 $789

PRINTERS

Centronics

730 Serial $650

730 Parallel $598

737 Serial $854

737 Parallel $765

Diablo

1640 630 $2400

1650 Call

Epson-MX-80 Call

NEC

5510 Call

5520 Call

Okidata - Microline 80 $524

Qume

5/45 Call

5/55 Call

Teletype

Model 40 Call

Model 43 w/Pinfeed . . Texas Instruments

810 Basic. . .'

810 Loaded

820 KSR Basic

820 KSR Package . . .

$1005

$1516 $1739 $1732 $1916

COMPUTERS

Altos Call

Dynabyte Call

Northstar

HRZ II-32K D (Assm) $2300

HRZ II-32K Q (Assm) $2665

Zenith

Z-89 48K $2210

DISKETTES

BASF

5V4-0 Sector S/S D/D (Qty 10) $33 5/4-10 Sector S/S D/D (Qty 10) $33 5V4-10 Sector D/S D/D (Qty 10) $37

Memorex 57.-10 Sector S/S D/D (Qty 10) $27

Dysan

574-10 Sector S/S D/D (Qty 10) $37 574-10 Sector D/S D/D (Qty 10) $42

Scotch

574-0, 10, 16 Sector (Qty 100) $275 8"-0, 32 Sector (Qty 100) $275

(BUY, SELL, TRADE

Experienced Equipments

Soroc IQ 120 ..$500 Centronics 779 Tl 810 Basic . . $1200

TVI 912 $550

TVI 920 $600

Qume Call

Diablo Call

Centronics 730 Teletype 40 $3400 NEW |

Comprint $400

Z-89 Call

Sanyo15"Monitor $195

Prices reflect 3% cash discount. Product shipped in factory cartons with manufactures warranty. Add 2%, a minimum of $5, for shipping and handling.

|UJ

GOmPLTTER _^_ uJRRjHOUg £$

2222 E. Indian School Rd. • Phoenix, Arizona 85016 (602) 954-6109

Store Hours:Tues.- Friday 10-6 MST Saturday 10-5 MST

Pascal programs. As mentioned above, when appropriate, POKE and PEEK can be substituted whenever the variable "memory" is used to address memory.

When a call-by-value is made to an external procedure using scalar parameters, the Pascal interpreter places the values of the parameters on the stack in reverse order of declaration in the procedure, followed by the Pascal return address. External functions have 4 additional bytes added to the stack before the Pascal address. When a call-by-variable (or a call-byvalue using nonscalar parameters) is made, a pointer to the variable is loaded on the stack. The difference in these calls is illustrated in the definitions of POKE, PEEK, and DIALIT.

The declarations for NATIVECODE start with the definitions for two macros and several global equates; these declarations are available to all the routines in the file. One macro pops (removes) 2 bytes from the stack (this implementation of Pascal is 2-bytes-per-word oriented) and saves them in successive locations specified by the parameters in the call; the other macro reverses this.

The global equates BIOSIN and BIOSOUT establish the addresses of two soft switches for gaining access to the Apple's BIOS. One reference to BIOSIN switches it into programmable memory while two successive references enable writing to the BIOS section of memory; a reference to BIOSOUT switches the BIOS out and the Pascal interpreter in. The declaration for CONCHECK establishes it as the starting address in the BIOS for the routine that polls the Apple's keyboard. VIDOUT is the address of the routine for displaying characters on the video monitor.

The procedure DIALIT illustrates call-by-value with a nonscalar value: a pointer to the number to be dialed is passed to the program. After storing the pointer, the routine prepares to dial by setting the temporary locations HANGUP and PICKUP and finding the length of the number. Dialing is accomplished by alternating the phone between the onhook and offhook states. (We assume the phone is off the hook when the routine is called.) The recommended dialing protocol is 61 ms onhook followed by 39 ms offhook with an interdigit delay of at least 600 ms.

The procedure SNDCHAR is used

Listing 3 continued:

P32e( output )i

2oto;;y( 0»5 )»

writeln1;'Enter the Fhone number.');

writeln i

write* ' —> ' )r

re3dln'! number )r

2et3ci3cntrl( word)i

P32e(output)»'

2oto>;yi Of5 )■

writei'Preparing to di3l» pie3se wait...' )r

init3cis( word)?

picKupJ

setniode( originate»hiah )>

writeln('OK' )i

disl( number )i

writeln >

writeln('U3itir,a for carrier..»')>

w3itforc3rrier»

end;

PROCEDURE terminal? VAR chrCHARi

error{INTEGER;

1 BEGIN p3Se(output )i 2oto>;y(0i5)i'

writelnt'C3rrier OK. Begin coBaunic3tions.')> en3bletr3nsnii t j REPEAT IF sci3error THEN IF NOT C3rrier THEN BEGIN

unitcle3r( 1 )> exit(terminal)i END ELSE BEGIN

write( '*' )i error i=peek( d3t3in )i END ELSE IF rcvrfull

THEN 2etch3r(ch) ELSE sendch3r; UNTIL NOT C3rrierr

end;

FUNCTION tryssSsmtBOOLEAN; YAR snswrtCHARi BEGIN REPEAT

P32e( output);

2oto>:y(0>5)i'

write('No C3rrier. Try 333in? (Y/N )->')>

re3d( 3nswr )!

writeln?

try323inl=3nswr IN C'Y'r'y']; UNTIL 3nswr IN L'V ,'N','y'.'n' li

end;

BEGIN C fullduple;-: 3 REPEAT di3lup; IF C3rrier THEN termin3i; UNTIL NOT try3=J3in; h3naup; END.

126 February 1981 © BYTE Publications Inc

Circle 79 on inquiry card.

STOP PLAYING GAMES

ilFHiliMJiriKM i

Corvus Transforms the Personal Computer into a Powerful Business Tool.

In business, professional offices, and schools throughout the world, thousands of Corvus intelligent peripherals bring mass storage, increased speed, and multi-user capability to a variety of microcomputers. Current applications include accounts receivable and payable, medical records, mailing lists, inventories, word processing, insurance, mathematics and science, and other large and complex files.

Corvus proven Winchester disk technology provides 10 to 80 million bytes of capacity, fully compatible with your current operating system. This is up to 500 times the capacity of a floppy disk.

The Corvus CONSTELLATION links up to 64 computers in a state-of-the-art multi-processor network. It provides shared mass storage, pipes for inter-computer communication, and system spooling for sharing of peripherals such as printers. Performance far exceeds that of larger and more expensive networks.

Backup data protection and archival storage are provided by the Corvus MIRROR (Patent Pending), a lowcost backup using standard video cassette recorders.

Contact your local Corvus dealer for the full story about these innovative new products. .

CORVUS SYSTEMS

., • 2029 OToole Avenue : * San Jose, California 95131 t (408) 946-7700/TWX 910-338-0226

&

Circle 80 on inquiry card.

Texas Instruments

INCORPORATED

Stock market programs, oil field calculations, real estate software, and data for insurance rates are some of the many programs originally written for the Tl 59/58 calculator and then converted to a custom Solid State Software" module. Companies or individuals can permanently store up to 5000 program steps of their unique software in this nonerasable module.

The services at American Micro range from shipping finished modules created from submitted formulas or programs to renting and selling the emulator software system that enables onsite development.

COSTS

Programs less than

1000 steps ........ $16/module

Programs between 1000 and

2000 steps $30/module

Programs between 2000 and

5000 steps $50/module

Minimum order is 250 modules

705 Bowser

Richardson, Texas 75080

(214) 238-1815

Here is a complete package of building blocks for developing remote communications systems.

to transmit characters through the modem. It does not check to see if the ACIA transmitter register is empty; this should be done in the calling program using "transempty". Location CONBUF is the start address for the BIOS's console keyboard buffer, and WPTR and RPTR indicate the number of characters written to and read from the buffer. BUMP is the address of a routine that updates these numbers.

SNDCHAR first polls the console keyboard. If there is a character in the buffer, it loads it into DATAOUT, then calls the output routine on the modem. At the end of all this, the address for returning to Pascal is still on the top of the stack, so an RTS (return from subroutine) instruction transfers control to the calling program.

In GTCHAR, VIDOUT is the address of the BIOS routine for sending characters to the video monitor. GTCHAR (analogous to SNDCHAR) assumes the ACIA's receiver register is full, a condition that should be checked in the calling program. The routine starts by saving the Pascal return address, discarding 4 bytes of stack bias, and polling the Apple's keyboard. It then fetches the character from the input location DATAIN, pushes it on the stack as the function result, and jumps to VIDOUT to display the character.

Using the Unit

At this point, we need only compile the unit, assemble the file NATIVECODE, link the two, and store the resulting final code in a library in order to use the unit. The program "fullduplex" (see listing 3) illustrates the use of the unit. The program also makes a call to the external function PEEK.

The main body of "fullduplex" and the procedure "dialup" are selfdocumenting. As for "terminal", the procedure continues sending and receiving characters until an ACIA error is found. If the error is the lack of a carrier, the program hangs up the

phone, clears the keyboard buffer of any junk, and exits "terminal" to "tryagain". If any other error is encountered, the character "§" is written to the video display and the receiver register is emptied to clear the error condition. I have used this program to communicate with several time-sharing systems and it has no problem keeping up at 300 bps.

Modifying the Apple's BIOS

The procedures presented thus far are quite adequate for a variety of dumb terminal applications, but they are not particularly well suited to mass-data transfer applications such as transmitting preprocessed files or whole volumes. For the latter, we would like to make use of the repertoire of UCSD Pascal intrinsic procedures for processing files. The key to using these procedures is an understanding of the BIOS (basic input/output system).

Each implementaton of UCSD Pascal, such as Apple's, requires an interpreter and a BIOS to support it. Roughly speaking, the interpreter translates p-code (the code emitted by the Pascal compiler) into machine language, and the BIOS handles the physical I/O to system devices. The BIOS modifications discussed below apply only to the Apple and may require revision if new versions of the BIOS are released. Hints on modifying another system's BIOS may perhaps be found in the UCSD Pascal User's Manual published by SofTech Microsystems. However, it is likely you will need a commented listing of your BIOS; I obtained a copy of the Apple BIOS from Apple in the form "The Preliminary Guide to Interfacing Foreign Hardware."

To fully explain the operation of the BIOS and the options the programmer has for modifying it would require a great deal of discussion. Instead I will provide a summary of its operation and offer a set of modifications that have worked for me.

Whenever a call for input or output is made from a Pascal program, the interpreter formats the data and determines which device is being called. Following this, the BIOS is switched in and then determines how the device is interfaced with the system. As currently configured, the Apple's interpreter and BIOS can recognize four types of external

Text continued on page 136

128 February 1981 © BYTE Publications Inc

THE UNBEATABLE S-100

MEMORY

?,,*

That's the MEASUREMENT systems & controls DMB Series of S-100 bus memory modules, fully compatible with ALPHA MICRO, CROMEMCO, DYNABYTE, NORTH STAR, MP/M, and most other S-100 systems.

Definitely a winner, the DMB Series is available with Bank Select (DMB6400) or without (DM6400) and utilizes industrial quality construction, provides outstanding reliability, and is backed by dedicated customer service and a one year guarantee.

The DMB6400 uses I/O port addressing for the bank select feature. A switch provides the ability to select any one of the 256 I/O ports for addressing the memory banks. The memory is configured as four totally independent 16K software selectable banks, with each bank addressable on any 16K boundary.

Systems

Group

a Division of MEASUREMENT systems &. controls

incorporated

Outstanding features such as those listed below make the DMB series the UNBEATABLE S-100 Memory:

• Four independent 16K software selectable banks.

• Each bank is independently addressable on any 16K boundary.

• Switch selectable bank sizes — from 16K to 64K in 16K increments.

• Eight banks (512K) per I/O port for each of the 256 ports.

• Z-80 4MHz operation with no wait states using transparent refresh.

• On-board diagnostic LED's.

• Low power — 8 watts maximum.

• Reliable, tested and burned-in memory.

• IEEE S-100 compatible timing.

• One year guarantee.

• Attractive Dealer & OEM Prices.

See your nearest computer dealer, or contact us for the complete story on the UNBEATABLE S-100 Memory.

867 North Main St. / Orange, Calif. 92668 / (714) 633-4460 TWX/TELEX: 678 401 TAB IRIN

Libraries everywhere have found the easy way to fill photocopy requests legally and instantly, without the need to seek permissions, from this and over 3000 other key publications in business, science, humanities, and social science.

Participation in the Copyright Clearance Center (CCC) assures you of legal photocopying at the moment of need. You can:

Fill requests lor multiple copies, intertibrary loan (beyond the CONTU guidelines), and reserve desk without fear of copyright infringement.

Supply copies simply and easily from registered publications. The CCC's flexible reporting system accepts photocopying reports and returns an itemized invoice. You need not keep any records, our computer will do it for you.

The Copyright Clearance Center is your one-stop place for on-the-spot clearance to photocopy for internal use. You will never have to decline a photocopy request or wonder about compliance with the law for any publication registered with the CCC.

For more information, just contact:

"1

Copyright Clearance Center

21 Congress Street

Salem, Massachusetts 01970

(617) 744-3350

a not-for-profit corporation

NAME

TITLE

ORGANIZATION

ADDRESS

CITY

STATE

ZIP

COUNTRY

TELEPHONE

Listing 4: External procedure that modifies Apple BIOS for use with the Micromodem II. This expands the Apple's utility beyond that of a dumb terminal, allowing mass transfer (and processing) of whole files via the Micromodem II.

.PR0C SYSGEN

BIOSIN

.EQU 0C083

BI0S0UT

.EQU 0C08B

C0NCHECK

.EQU 0D681

ACIA

.EQU 0C0A6

DATAOUT

.EQU 0778

DATAIN

.EQU 0C0A7

M0DEH

•EQU 0C0A5

0UTA

.EQU 0C202

IC0M

.EQU 0D7A3

RINIT

•EQU 0D79C

RWRITE

.EQU 0D80?

UC0H

.EQU 0D81F

RC0M

.EQU 0D85D

RREAD

.EQU 0D84E

LDA BIOSIN

LDA BIOSIN

LDY #00

XRINIT

LDA PRG2,Y

STA RINITfY

INY

CPY #03

BCC XRINIT

LDY #00

XlCOtt

LDA PRG3,Y

STA ICOhSY

INY

CPY #0A

BCC XIC0M

LDY #00

XRWRITE

LDA PRG4,Y

STA RURITErY

INY

CPY #06

BCC XRWRITE

LDY #00

XUCOM

LDA PRG5,Y

STA WCOMfY

INY

CPY #11

BCC XWC0M

LDY #00

XRREAD

LDA PRG6,Y

STA RREAD»Y

INY

CPY #03

BCC XRREAD

130 February 1961 © BYTE Publications Inc

Listing 4 continued on page 132 Circle 82 on Inquiry card. >

o

c

V

>

>s =

.o r rt c

z

o c

»t <"

ib +,

i/i

>s CO

>s l. I. V

•O

>s

o o- o co in 03 '

El

+: CD Q. .

E^

O -Q >. 03

^ b

?co i'i

O CD " >

CO *0) IS

+-r CD

CD 2 O -_. 03-^

o <" S

51.1

g CO T3

"5

CD ^3 O 05

5 5

CO £ > cc

CD

CD

ca c ^ Q)

CO

E

CO _

b) QJ 25

a.- .

Q CD Q) O

go

o

o 5 E~

82

•£3o

T3 CD

t X 03 CO

>

co

CD

03

§t£

CD

0

CO

gO-E

a 5 c o

o <"

i 03

O -C

3

a.

03 CO -^ CO > c <S CO ^, O

CO

E <D

Q3 ^ C % 03 O

>Oco

co

03

E-c

-4= o

03"°?^

n as O > £00 4g ccO

S 03Q

S o ca

ES

5g

co . co CD C .i= CO O " Q3 CO— CO

3

o 5.5

s= o

03 C

03 03 co o a?

X rn -i '.

en

CO ^

co

1°

CC

h- _o ^;

o^EO

« ,- CD

^ CO 0) O

D- i —•

D 6 > «'

W — m S fc

>co IS ti o

c < w ™ S cc

o = C5 5 ^O 00 — cc •" ,„ (/J j, a> uj .E J° ^

O £so^S

o 5 § § « o

awES£

CD

CO

CO

d o in id

w> o.

Ifil s

OE |2 O

S3 §S jo

T3

C <0

w o

JO 0)

w

Circle 83 on Inquiry card.

WHAT'S

BETTER

THAN AN

ISAM

And Will Turn

MICROSOFT'S

BASIC

COBOL

FORTRAN

DIGITAL'S PL/1-80

CBASIC

PASCAL/MT+

S-BASIC

CROMEMC0 16K BASIC

info first class application languages?

MICRO B+

The first and most complete implementation of B-TREE index structures for microcomputers. B-TREES eliminate index file reorganization.

Search

An index of over

10,000 Key

Values In Less

Than One

Second

On A Floppy Disk System for only

$260.00!

System Houses: MICRO B+™

Available in Language C

Fair Com

2606 Johnson Owe Columbia. MO 65201 (314)445-3304

^'1980 Fair Com

Shipping $4 USA / $8 Foreign We accept VISA and MASTERCARD

PL/l-80 is o trademark of Digital Research C8ASIC is a trademark of Compiler Systems. Inc. S-BASIC is a trademark of Topaz Programming PASCAL/MT- Is a trademark of MT Micro Systems

Listing

4 continued: LDY #00

XRCOH

LDA PRG7,Y STA RCOMfY INY

CPY *0F BCC XRCOM

LDA BIOSOUT • RTS

PRG2

•BYTE 4Cf0A3f0D7

JJMP

ICOM

PRG3

.BYTE 0A9f03

jlda

♦03

• BYTE 8DfOA6fOC0

J STA

ACIA

•BYTE 0A9f 15

JLDA

♦ 15

.BYTE 8Df0A6f0C0

JSTA

ACIA

PRG4

.BYTE 0A8

JTAY

•BYTE 0A2f00

JLDX

♦00

.BYTE 4CflFfOD8

JJMP

WCOM

rRG;

•BYTE 20f81»0D6 JJSR CONCHECK .BYTE OADfOA6fOC0JLDA ACIA .BYTE 29f02 •BYTE 0F0f0F6 .BYTE 8Cf78f07

.BYTE 20f02»0C2 .BYTE 60

JAND #02

JBEQ WCOM

JSTY DATAOUT

JJSR OUTA JRTS

PRG6 PRG7

.BYTE 4C»5DfOD8 JJMP RCOM

.BYTE 20f81f0D6 JJSR CONCHECK .BYTE OADfOA6fOC0JLDA ACIA .BYTE 4A JLSR A .BYTE 90,0F7 JBCC RCOM .BYTE OADfOA7,OC0JLDA DATAIN .BYTE 0A2»00 JLDX ♦OO .BYTE 60 JRTS

.END

PROGRAM startupJ

PROCEDURE sysSenJEXTERNALJ

BEGIN suss^en J

3oto>;y(0f5)J

writeln*'Welcoee to Dr. Wo's Apple Pascal!' )J writelnJ

writeln('The satem has Just been modified to')J writeln<' enable communications through the' )f writeln('Hicrotodem II in slot 2.')J writelnJ

writeln('Please set the DATE usins1 the Filer.')J END.

Listing 5: A program to test the Micromodem II system. The program prompts the operator, then puts the modem through its various modes of operation.

PROGRAM tesUodem!

(This program tests the transmission and reception of the printing characters through the Micromodem II installed in slot 2 on the Apple's board. The program uses the Library Unit '»icromodem' and custom 1/0 drivers installed as modifications in the Apple's BIOS.}

Listing 5 continued on page 134

132 February 1981 © BYTE Publications Inc

Time is precious

let,

y lose it?

tATTERY SUPPORTED CALENDAR CLOCKS

PDP-111 ...........TCU-100-$495 w

,rTffft TCU-150«$460 LSI-11/21 TCU-50D • $325

Multi-Bus2 TCU-410 • $325

EXORcisor; , TCU-68 • $325

HP 2100 TCU-2100 • $395 Serial Line Clock . SLC-1 • $640

Lockheed SUE TCU-200 *$550 (RS 232 or 20mA) Microprocessor controlled. *■ ■ -i»«- -a "-i-^i i ^^ Znnr- Auto message intercept and response. Naked Mini 4 TCU-310 • $385 10 Digit display option $190.

If automatic and accurate date and time entry three months). Timing is provided by a crystal is important to your system on power-up — controlled oscillator. Prices are U.S. domestic you need a Digital Pathways battery sup- single piece. Quantity discounts available. ported calendar clock. All Digital Pathways'

TCUs have on board NICAD batteries to maintain For more information on these timely products, date and time during power down (typically up to contact:

j. ill

^~" ff^v Digital Pathways Inc.

[Trademark of Digital Equipment Corp. S ll^m^\ 1260 L'Avenida

trademark of Intel Corp. ( ^^w-Zr-^^ I ««_ * ■ \r ^* „.«„..«

^Trademark of Motorola Inc. \f^Kli J Mountain View, CA 94043

4 Trademark of Computer Automation Inc. >>>s^## ^^ Phone: (415) 969-7600

DIGITAL PATHWAYS

Circle 84 on inquiry card. . byte February i98i 133

Circle 85 on inquiry card.

^TV eystems, inc.

No. P7 Zenith Data Systems Z89F Microcomputer with Z47 8" Dual Disk Drive

ZENITH DATA SYSTEMS LIST OUR PRICE

Z89-FA Microcomputer System $2,895 $2,495

48KB, 5.25' Disk, HDOS Z89-G A Microcomputer System $2,595 $2,259

48KB, HDOS (No Disk)

Z19 CRT Terminal SPECIAL $ 950 $ 795

Z87 Dual 5.25" Disk Unit (200 KB) $1,195 $1,095

Z47-BA Dual 8" Disk Unit (2MB) NEW $3,695 $3,295

CP/M V.2.2 for Z89 $ 150 $ 140

HDOS Operating System (with BASIC) $ 150 $ 140

Microsoft BASIC V5.1 for CP/M $ 175 $ 160

Microsoft BASIC V5.1 for HDOS $ 150 $ 140

Microsoft FORTRAN $ 195 $ 180

Microsoft COBOL $ 395 $ 350

Word Processing for Z89 $ 395 $ 375

To Order: Send Check or Money Order to: PK Systems, Inc., 113 North

Center, Bloomington, IL 61701. Allow two weeks for personal checks to clear.

For COD Orders, add 5% for handling and service charge. Rush orders, add

$50.00.

Shipping: Freight collect, FOB Bloomington. We ship UPS, atr freight, or

motor freight.

PK Systems is an Authorized Zenith Data Systems Dealer and Zenith Seivice

Center PE^^SBW < B^MalrfVr-'iiHllKl CP/M is a trademark of Digital Research

SPECTACULAR

Offers*

BASF"FL£XYD1SK" Superior quality data storage medium, certified and guaranteed 100% error free.

5V4" or 8"* . _ .

Diskettes 10/524

5V4" or 8" Vinyl Storage Pages

10/$5

Write for quantity discounts "Single sided / Single Density

SFD CASSETTES "Super Ferro Dynamic" Using the finest Agfa PE 611 tape in a professional quality housing.

C-10 Cassette

Sonic Weld ._

Housing 10/$ /

Add 10C p/cassette for 5 screw housing

Cassette Album , . __

Page $1.89

Write lor quantity discounts

■•" •rX7

LIBRARY CASE 3-ring binder album, Protects your valuable programs on disks or cassettes. Fully enclosed and protected on all sides similar to Kas-sette storage box.

Library 3-ring binder $6.50

5'/«'miniKas-sette/10 $2.49 8" Kas-sette/10 $2.99

Write for quantity discounts

DISKETTE DRIVE head cleaning kits prevent head crashes and insure efficient errorfree operation.

5V4" or 8" KIT

INTRODUCTORY PRICE $19.50

HARDHOLE 8" applicator $4.00

reinforcing ring of 51/,- applicator S3.00

tough mylar protects g., ,„ hardho|es ,s0, . s8.00 your disks from Lrf., h.,Hhnl.. ,Bni aft nn

damage.

5V<" mylar hardholes (50) SB.00

ABM

PRODUCTS 631 "B" St San Diego, CA 92101 (714) 235-6602

VISA • MASTERCHARGE • MONEY ORDERS CERTIFIED CHECK* FOR PERSONAL CHECKS ALLOW2 WEEKS • COD. REQUIRES A 10%

DEPOSIT • CAL RES. ADD 6% SALES TAX

MIN. $2 SHIPPING & HANDLING • MINIMUM

|ORDER $10 • SATISFACTION GUARANTEED

OR FULL REFUND.

Listing 5 continued:

USES roicroniodeniT

CONST lowch3r= ' 'i C blank 3 hi5hch,3r = 'z' J

VAR choutrchin.CHAR; error count! INTEGER? «!ARRAYlmode] OF STRINGC10], bJARRAYCbsudrste] OF STRINGC103J remin»remout!INTERACTIVE,

BEGIN C main 3

reset( reminr renin!' )> rewrite( remout.'remout!' )>

m[answer]!='answer'J ni[ori5in3te]! = 'oris:in3te' 5 b[low]! = '110 baud', b[hiah]! = '300 baud' i

FOR nid! = 3nswer TO originate DO FOR br.=low TO hish DO BEGIN FBSeC output )> 5oto>;a(0»5),

writeln(' Testing ' rraCnid]?' mode> '»b[br])» writelnJwriteln?

writeln(' Resetting modem and ACIA.')» write('Please wait...' )> setmodemf self test-fr-esetf 135 )> initsci3(21 )i picKupj

setmode(mdfbr )5 writelnCOK' )i writeln?

write('Please wait for carrier...'); enabletransaitJ waitforcarrierJ writelnC'OK' )>

writeln?

writeln(' Beeir; test*..')? errorcount!=OJ

FOR chout!=lowchsr TO hishchar DO BEGIN

write( remoutfchout )>

resdf remin»chin )>

IF (ord(chout )-ord( lowchar )) HOD 40<39 THEN write(chout) ELSE writeln(chout )J

IF choutOchin THEN BEGIN

errorcount.=errorcount+l5

writelnC'Error in sending '»chout)i

end; end;

writelnJwriteln;

writeln('Total errors this test= '»errorcount)»

writelnj

write('T«pe <ret> to continue...')>readln;

end;

134 February 1981 © BYTE Publications Inc

Circle 86 on inquiry card.

Circle 87 on inquiry card.

i^c

NEW DISK SYSTEM POLISHES APPLE

I

I

Micro-Sci's new disk drive family really makes your Apple shine.

Both the A-40 and A-70 offer extra performance plus the ability to read existing diskettes written on Apple Disk II systems.

And a jumper selectable boot prom for 13 and 16 sector interger Basic or 8 sector Pascal comes standard.

The Model A-40 actualy costs a lot less than Apple Disk II drives. Yet it provides 40 tracks instead of

35, along with up to 20K increase in capacity. Maybe an extra 20K isn't anything to write home about, but the speed sure is—5 ms track to track vs. Apple's 15 ms.

The Model A-70, on the other hand, features twice the tracks and capacity of the Apple Disk II, but it costs only a few dollars more.

The secret of outstanding performance and reliability is a stateof-the-art design incorporating a band positioner, instead of a plastic

fj-sa

cam, plus an improved media centering system.

SPECIAL DISCOUNT.

One A-40 plus controller is priced at only $495 and the second drive isjust$395.You can save up to $200 per system over Apple II drive prices.

And you can save even more if you act now. Contact us today for a special $50 introductory discount on your Micro-Sci A-40 or A-70 system order.

MICRO-SCI 1405 E. CHAPMAN AVENUE ■ SUITE E • ORANGE, CALIFORNIA 92666

MICRO-SCI IS A DIVISION OF STANDUN CONTROLS, INC. Apple and Apple II are registered trademarks of APPLE COMPUTERS INC., SAN JOSE, CALIFORNIA

714/997-9260

Text continued from page 128:

physical devices—consoles, printers, disks, and remote input/output devices (such as modems)—provided these devices are interfaced via an Apple-brand card. For nondisk I/O, the Apple's BIOS recognizes the Apple communications, serial, and parallel-printer cards. If a foreign card is plugged into a slot, the Apple will know that something is there, but will not know how to communicate with it unless the card's setup happens to coincide with one of the Apple cards. Such is the case for the Micromodem interface: the Apple thinks it is communicating with a remote device via an Apple communications card, but it can't do I/O because of an address mismatch. The solution is to insert the correct addresses.

The Apple's BIOS is set up to do three things with the modem: initialize it, read from it, and write to it. In each case, the BIOS receives control from the interpreter, jumps to a location reserved for the appropriate operation with the remote I/O device, determines which type of card it is dealing with, then jumps to a location reserved for that combination of

card and operation. After completing I/O, it returns control to the interpreter. This combination of jumps was observed in my modifications. Since I have no Apple communications cards connected to my system, I customized the locations to suit the requirements of the Micromodem. These modifications are applied at system startup time via an external procedure SYSGEN hosted by the program "startup".

The procedure SYSGEN (see listing 4) first enables writing the BIOS. Then it modifies the routine located at RINIT so that a JMP to location ICOM is made. In the unmodified BIOS, RINIT is the name of a routine for initializing the remote device: it first determines what type of card is in slot 2; after finding a communications card it jumps to ICOM to initialize the card. Under these modifications, control is transferred to ICOM immediately. SYSGEN next modifies RWRITE, the "write-to-remote" routine, and WCOM, the "write-to-comm-card" routine. Similar to the unmodified initialization routines, the interpreter passes control to RWRITE, which determines the type of card occupying slot 2.

DIGITAL

SPEECH is now a way street.

p(Jt/Output Speech Digitizer. Permits talking p'rograms. I/O capability allows interactive teaching programs and speech-prompted data input formats. Use output for speech directed activities in business systems, announcements in a control-room, or sound effects in entertainment programs. Easy to use because input as well as output is under user control with special software operating system. Available at Apple Dealers worldwide.

ma

mntain Computer

Incorporatkd"

300 Harvey West Blvd., Santa Cruz, CA 95060 (408) 429-8600 TWX 910 598-4504

Upon finding a communications card, it transfers control to WCOM. SYSGEN closes with modifications to RREAD and RCOM.

One can implement the modifications, as I have, in a program that is executed each time the system is booted up. First assemble SYSGEN, then link it to a Pascal host "startup", and then store the final code in the file SYSTEM.STARTUP on the boot disk. The program will be executed automatically at boot time.

A Test Program

The program "testmodem" tests the modem and the BIOS modifications. It starts by opening the files "remin" and "remout" and associating them with the volumes "remin:" and "remout:" respectively. The latter are the names given to remote I/O devices under Apple UCSD Pascal. Following this procedure, the program sets up some strings to prompt the operator, and the nested FOR...DO loops put the modem through its various operating modes.

When the statement "write (remout,chout);" is encountered, the interpreter determines that a call for output to slot 2 is being made. At this time control is transferred to the BIOS location RWRITE. In order for execution to proceed satisfactorily from there, the system must recognize the card in slot 2. The situation is similar for the statement "read (remin,chin);". Thus, the program serves as a test of the BIOS modifications as well as the modem.

Summary

The library unit "micromodem" and the BIOS modifications presented here are a complete package of building blocks for developing remote communications programs using the Micromodem running under the Apple implementation of UCSD Pascal. Techniques similar to those described here should enable operators of other systems to enjoy the same advantages. ■

References

1. Grogono, P. Programming in Pascal. Addison-Wesley, 1978.

2. Hyde, D J. Micromodem II Owner's Manual, 2nd edition. Norcross GA: Hayes Microcomputer Products Inc, May 1979.

3. "The Preliminary Apple Pascal Guide to Interfacing Foreign Hardware." Cupertino CA: Apple Computer Co, Dec 1979.

4. UCSD Pascal User's Manual. San Diego CA: SofTech Microsystems, 1978.

136 February 1981 © BYTE Publications Inc

Circle 88 on inquiry card.

Circle 89 on inquiry card.

LOBO'S NEW LDOS

Puts muscle in your

TRS-80*

LOBO DRIVES' new LDOS™ Disk Operating System is loaded with outstanding features that will enable you to realize the full power and potential of your TRS-80r With LDOS, you can support up to eight drives (51/4 and 8-inch drives, double-sided drives, double-density drives, 80-track drives), including the new 8-inch and 51/t-inch Winchester fixed disk drives, in any combination.

Other LDOS muscle building features include: ISAM accessing techniques; keyboard typeahead; Graphic string packer; Dated files, Marked files; File transfer by class; Built-in

•TRS-80 is a registered trademark of Radio Shack, a Tandy Company.

drii/esr^

I

INTERNATIONAL

LOBO DRIVES, INT'L 354 South Fairview Ave. Goleta, CA 93117 (805) 683-1 576

lower case display drivers; Non-breakable AUTO and DO commands, and many, many more.

LDOS is the perfect operating system to use with your LOBO DRIVES LX-50 or LX-80 expansion interface and disk drive subsystems. There's even an 800 number for instant service. To find out how you can put more muscle into your TRS-80, contact your nearest LOBO Drives dealer or call or write. ~7~,

LDOS is available:

A. Operating System Diskette with Master Reference Manual $139

B. Master Reference Manual ' Only $25

Circle 90 on inquiry card.

8" DISK CONTROLLER

NOW-DOUBLE SIDED OPTION!

• DOUBLES APPLE ][ STORAGE

• APPLE DOS COMPATIBLE

• SHUGART 800 OR 850 COMPATIBLE

• IBM 3740 DATA ENTRY CAPABILITY

• CP/M, UCSD PASCAL CAPABILITY Available at your local APPLE Dealer: $400.

SORRENTO VALLEY ASSOCIATES

11722 SORRENTO VALLEY RD. SAN DIEGO, CA 92121

FEBRUARY

ALL ITHACA

INTERSYSTEMS

HARDWARE

20

%

OFF LIST

We carry the largest variety of S-100 products in theworld. For a special cash price please call.

For our 1981 Catalog, please write

Subject to available quantities. Shipping and insurance extra. VISA and Master Charge accepted at no additional charge lor orders over $500.00.

S-IDD,inc.

7 White Place Clark, N.J. 07066 TQ1 201-382-1318

Hours: Mon. - Fri. — 10 a.m. to 6 p.m.

Technical Forum

Recording with Current Instead of Voltage

David Hein 2821 Chariot Lane Garland TX 75042

Most of the articles I have seen on the theory of mass storage using cassettes begin with a discussion of how the magnetization of the tape depends on current flow, and how changing the head-drive current creates cells of different magnetization. During a read, it is normally assumed that the sharper the transitions between current and lack of current, the higher the output and the greater the density (or speed) that can be used.

Yet after all this discussion on current, head drive is most often performed by a voltage amplifier driven to saturation. Current devices should be driven with current rather than voltage.

The circuit I use for this is simple. It consists of two current drivers, some control gates for writing, an RS flip-flop for reading, and an amplifier with a gain of 200, capacitively coupled to a differential sense amplifier (see figure 1 on page 140).

Four channels along with voltage amplifiers easily fit on a two-sided, 4- by 6-inch card with standard 22-pin connectors (see photo 1). That's enough circuitry for two tracks each on twin transports.

My tape deck, which has digital (narrow-gap) heads is capable of 8 K bps (bits per second) at 5 ips (inches per second). My neighbor's standard cassette deck is capable of 2400 bps at 1% ips. ■

Photo 1: Finished version of the circuit shown in figure 1. This 4- by 6-inch board with 22-pin connector has enough room for the circuitry of two tracks each on dual recorders.

138 February 1981 © BYTE Publications Inc

Circle 91 on inquiry card.

Thinking of Data Base for Your Micro?

Check these results from MDBS:

Leonard Overton, President of LS Business Systems, reports:

"The MDBS data base system is now the foundation for our future application products. This is because MDBS helps us to produce more flexible applications... quicker. System design changes are made easily. Time required for loading and debugging is greatly reduced."

Check these features and support:

•MDBS is more complete—

j Network and hierarchical data structures

J Non-procedural query language

J Host language support including: BASIC, COBOL, FORTRAN, PASCAL, PL/I

■j Data base recovery

v/Data base restructure utility

</ Available for popular Z-80, 8080, 6502, 8086 and Z-8000 based systems

• MDBS has complete documentation

■J DBMS Guide and Primer for fundamentals

yMDBS systems documentation

• MDBS has complete service and support, including—

•j System updates and enhancements

/Training

J Phone consultation

-/ Newsletter

So if you're thinking of data base, check with us.

Use the coupon below.. .or better yet, give us a call today.

Setting standards of excellence (or data base software.. .worldwide.

Micro Data Base Systems, inc.

Market Square, Box 248 Lafayette, Indiana 47902 317-448-1616

Dealer/distributor/OEM inquiries invited.

YES, please send me more information on the remarkably flexible MDBS Data Base System.

Name

(Please print)

Title

Company Address _ City

(State)

(Zip)

Phone

MAIL TO: Micro Data Base Systems, Inc. Dept. B P. O. Box 248 Lafayette, IN 47902

Circle 92 on Inquiry card.

BYTE February 1981 139

lA m

ia |6

Figure 1: /4 circuit for driving record heads with current rather than voltage. This simple circuit enables data transfer rates of up to 2400 bps (bits per second) on a standard cassette tape recorder.

140 February 1981 © BYTE Publications Inc

anew

is Dorn!

a better computer system any way you look at it.

The facts speak for themselves. The QUAY 500 SERIES offers more for the money than North Star Horizon® computers.

MORE TECHNICAL FEATURES. A single board computer instead of a backplane with multiple boards, means fewer parts, fewer interconnections and fewer problems □ additional disk capacity for more program storage □ DMA controlled disk transfers for increased system performance o on-board expansion capabilities for additional parallel and serial ports, and EPROM □ AC convenience outlets □ a more compact design. IMMEDIATE DELIVERY. The 500 SERIES is available off the shelf for virtually immediate delivery. No waiting for far off delivery dates for this one.

LOWER PRICE. The advanced technology engineered into Quay computers actually lowers our cost to manufacture. The price of the 500 SERIES is about 20% lower than the

Horizon-2-32K-D — and our 520 SERIES also offers significant savings over the Horizon-2-32K-Q. The bottom line is simple. There is a new star in the computer field. The 500 SERIES by Quay. It outshines all of the competition.

COMPARE FOR YOURSELF:

SPECIFICATION

QUAY 500

HORIZON-2-32K-D

Architecture

Single Board

S100 bus

CPU

Z80A, 4MHz.

Same

Dynamic RAM(std)

64Kb.

32Kb.

Disk drive type

Doubledensity

Same

No. of drives (std/max)

2/4

Same

Capacity per drive (on-line)

200 Kb.

180 Kb.

Direct Memory Access (DMA)

Yes

No

CP/M® disk operating system

Standard

Optional

Unit Price

$2,995.

$3,095.

Advanced single board modular design.

SPECIFICATIONS

QUAY 520

HORIZON-2-32K-Q

Disk drive type

Quad density

Same

Capacity per drive (on-line)

400 Kb.

360 Kb.

Unit Price

$3,495.

$3,595.

The QUAY 500 offers technical superiority—availability—a $2,500 price!

CP/M ^ is a registered trademark ol Digital Research

Horizon is a registered trademark ol North Star Computers, Inc.

ouAa

CORPORATION

P.O. Box 386, Freehold, New Jersey 07728 ■ (201) 681-8700 Factory: Route 34, Wall Township, New Jersey 07719

DISTRIBUTOR AND REPRESENTATIVE INQUIRIES WELCOME

Circle 93 on inquiry card.

BYTE February 1981 141

Dynamic Memory: Making an Intelligent Decision

Larry Malakoff

Measurement Systems and Controls

867 N Main St

Orange CA 92668

Mention the words dynamic memory to an S-100 bus user and the responses will vary from one end of the spectrum to the other. In the early days of the S-100 bus, many users had bad experiences with poorly designed dynamic-memory boards. The problems varied from inadequate memory refreshing to designs that worked with only a particular processor board. However, things have come a long way since then. For the vast majority of today's applications, dynamic memory offers the best cost/performance ratio available. With so many of the large S-100 computer manufacturers such as Cromemco, North Star, Vector Graphic, and others using dynamic memory in their systems, all users should seriously consider the advantages of including dynamic memory in their next system design.

Dynamic vs Static

In the S-100 world, static memory is the alternative to dynamic memory. When comparing the two types, three major advantages of dynamic memory are apparent. First, dynamic boards contain more memory than static boards. Even with the supporting control logic that dynamic memory requires, today's largest available S-100 memoryboard sizes are 64 K bytes for

About the Author

Larry Malakoff is the Marketing Director of Measurement Systems and Controls Inc, located in Orange, California. He has been involved in the design of 5-100 dynamic-memory boards and is currently working with customers to solve their application requirements for system memory. Larry received his Master of Science in Engineering from UCLA and has been involved in electronic design for over eight years.

dynamic memory and 32 K bytes for static memory. For those systems that require large amounts of memory, such as the Cromemco and Alpha Micro multi-user systems, the increased density of dynamic memory can mean the difference between having enough available slots on the motherboard for all the cards necessary to complete the system or not being able to fit all of the required cards into a given chassis.

The second and probably most important advantage of dynamic memory is the low level of power dissipated. This not only reduces the amount of heat generated, but also reduces the current requirements from the power supply. A typical 64 K-byte dynamic-memory board dissipates approximately 8 watts of total power compared to as much as 50 watts for 64 K bytes of static memory. This decrease in power dissipation of more than sixfold can make a big difference in the reliability of the entire system. This is especially true when the system contains more than 64 K bytes of memory, as in a multi-user application. Since the reliability factor for electronic equipment decreases exponentially as the operating temperature increases, the mean time between failures can be drastically improved by using dynamic memories in the larger memory-intensive systems.

The third major advantage of dynamic memory is cost. Historically, its cost has always been lower, and this will continue to be so due to the increased density of dynamicmemory circuits. Once an integratedcircuit manufacturer has regained the initial development investment (assuming the yields are about equal), the price for higher-density dynamicmemory circuits can be about the

same as for lower-density staticmemory devices. Since it takes sixtyfour of the 4 K-by-1-bit staticmemory devices to build a 32 K-byte memory board as compared to thirtytwo of the 16 K-by-1-bit dynamicmemory circuits to build a 64 K-byte dynamic-memory board, it becomes apparent, even when the control logic is taken into account, that a dynamicmemory board costs less to build than the corresponding static-memory board.

In comparing the two types of memory, there is one application where static memory may be a better choice. Not all types of DMA (direct memory access) controllers will correctly interface with all types of dynamic-memory boards. Depending on the particular DMA controller, static memory may be the only type that will work correctly. More will be said about this later.

Memory Features to Look For

Now that the general merits of dynamic-memory boards have been brought to light, it is important to discuss some of the differences between the commercially available designs, and what features in particular to look for when choosing a dynamic-memory board for your system. This discussion will be separated into two application areas —those requiring a maximum of 64 K bytes of memory and those requiring more than 64 K bytes of memory (for multi-user and multitasking applications incorporating software-controlled, bankselectable memory).

Many manufacturers make only one memory-board product that tries to bridge the gap between the two types of applications. However, these two applications require that the

142 February 1981 © BYTE Publications Inc

rhen you pick a Daisy. Pick Vista's V300 Printer

Vi/ta

Computer Company

$1895.

There are Daisies!... And, There are Daisies!... But Vista has a Peach!

The Vista V300 is exactly that, a "peach" of a daisy wheel printer both from the standpoint of price and performance.

Think of it, a printer at nearly half the price (when compared to models even remotely competitive in quality) combined with the ultimate in reliability, print quality, and flexibility.

Typical Comments: "Superb print quality!", "Highly reliable.", "Definitely letter quality. . . I can't believe the price tag.", "Best use I've seen yet of LSI Technology."

But judge for yourself — look at the V300 features and keep in mind this is a letter quality printer at dot matrix prices.

• Tractor option available

• Print Speed — 25 CPS (Optional 45 CPS for $2,195)

• Print Wheel — Industry standard 96-character Daisy Wheel (including the extended-life dual plastic wheels)

• Service — Prompt maintenance/service agreements available nationwide

• Interface — Industry standard parallel (RS232-C optional)

• Printable Columns — 136

• Warranty — 90 days parts and labor, one year parts only

• Proportional, bi-directional printing • Programmable VFU

• Extensive self-test functions • Hardware and software compatible

Vista does it again! Quality, Price and Performance with a peach of a daisy wheel printer.

nsff

IMMEDIATE DELIVERY

For Further Information Call Toll Free (800) 854-8017

AND, Vista Has a Complete V100 Word Processing System for Only $4995!

The Vista V100 is a complete word processing system that includes:

Exidy Sorcerer

Computer, 48K

V200E20 Disc Drive

System, Double

Density

Sanyo Data Display

Monitor

Vista V300 Printer

Full Character Daisy

Wheel

Wordstar, CPM 1.4

(Includes E Basic)

Can also be used for

Data Processing

The Vista Computer Company 1401 Borchard Street* Santa Ana, California 92705"

™CPM Is a trademark of Digital Research

714/953-0523

Circle 94 on inquiry card.

BYTE February 1981 143

memory used have different features, often resulting in a compromise where one or both of the application areas lacks the necessary hardware for a truly cost-effective solution.

Single-User Features

In a single-user system that requires 64 K bytes or less of memory, the most important feature to have is the ability to deselect memory in as small an increment as possible. For the majority of 64 K-byte dynamic-memory boards that offer this feature, 4 K bytes is usually the smallest block of memory that can be turned off.

la

(Some of the older 16 K-byte memory boards allow deselection to 1 K bytes.) This feature is necessary to allow the system monitor in readonly memory and memory-mapped controller cards to reside in the memory-address space without interfering with normal memory operations.

Another useful feature is the ability to buy a memory board in either a 16, 32, 48, or 64 K-byte size, with those boards containing less than 64 K bytes able to be expanded to 64 K bytes by inserting the necessary integrated circuits into empty sockets.

Photo 1: Different kinds of memory boards. These two 64 K-byte memory boards have fundamental differences that tailor them for specific types of systems. The Measurement Systems and Controls DMB6400 (photo la) is intended for multi-user and multitasking systems and provides a bank-select feature so that memory addresses may be shared by users. The DM6400 (photo lb) is produced specifically for single-user systems and has a deselect feature that allows memory-mapped peripherals to occupy any 4 K address block. Both boards are manufactured by Measurement Systems and Controls of Orange, California. Prices are $1195 and $895 respectively.

This gives the small user the ability to expand as necessary. It is important that the manufacturer test these boards as full 64 K-byte boards even though they may be sold as 16 K-byte boards. This is the only way the end user can be assured that the board will work when the extra devices are plugged in to increase the memory size.

Multi-User Features

Most multi-user and multitasking S-100 systems require bank-selectable memory boards. The requirements placed on the memory board for these applications are quite different from those placed on the single-user applications. A typical multi-user system might have an operating system of 48 K bytes and five user banks of 16 K bytes each. The operating system might occupy the upper 48 K-byte address space and be on all the time, while the five users might share the lower 16 K-byte address space. Only one user can be on at a time (there can never be more than 64 K bytes of memory on at any one time), but the operating system allows all five users to access the computer on a rotating timeshared basis. Through software control, each of the 16 K-byte banks of memory is turned on or off as required. This is usually accomplished by doing an OUT instruction to a particular I/O (input/output) port that the memory board is set to decode. The data on the bus then determines which banks are to be on or off.

A 64 K-byte dynamic-memory board optimized for this type of application would allow the user to implement the above example with only two memory boards. Other 64 K-byte dynamic-memory boards that compromise on the hardware design would require one 48 K-byte memory board and five 16 K-byte memory boards. In this case, the number of motherboard slots required increases, the total power dissipation increases, and the total cost of memory increases.

The difference between the two memory boards in the above example is in how the 64 K bytes of memory are partitioned into softwareselectable banks. The optimal design, considering the limitations of board "real estate," is to have four totally independent 16 K-byte banks of memory. This allows the user to have

144 February 1981 © BYTE Publications Inc

Circle 95 on inquiry card.

Multi-User

UniFLEX is the first full capability multi-user operating system available for microprocessors. Designed for the 6809 and 68000, it offers its users a very friendly computing environment. After a user 'logs-in' with his user name and password, any of the system programs may be run at will. One user may run the text editor while another runs BASIC and still another runs the C compiler. Each user operates in his own system environment, unaware of other user activity. The total number of users is only restricted by the resources and efficiency of the hardware in use.

The design of UniFLEX, with its hierarchical file system and device independent I/O, allows the creation of a variety of complex support programs. There is currently a wide variety of software available and under development. Included in this list is a Text Processing System for word processing functions, BASIC interpreter and precompiler for general programming and educational use, native C and Pascal compilers for more advanced programming, sort/merge for business applications, and a variety of debug packages. The standard system includes a text editor, assembler, and about forty utility programs. UniFLEX for 6809 is sold with a single CPU license and one years maintenance for $450.00. Additional yearly maintenance is available for $100.00. OEM licenses are also available.

FLEX

TM

Multi-Tasking

UniFLEX is a true multi-tasking operating system. Not only may several users run different programs, but one user may run several programs at a time. For example, a compilation of one file could be initiated while simultaneously making changes to another file using the text editor. New tasks are generated in the system by the 'fork1 operation. Tasks may be run in the background or 'locked' in main memory to assist critical response times. Intertask communication is also supported through the 'pipe' mechanism.

UniFLEX is offered for the advanced microprocessor systems. FLEX, the industry standard for 6800 and 6809 systems, is offered for smaller, single user systems. A full line of FLEX support software and OEM licenses are also available.

Box 2570, West Lafayette, IN 47906 (317) 463-2502 Telex 276143

'"UniFLEX and FLEX are trademarks of Technical Systems Consultants, Inc.

bank sizes that are any multiple of 16 K, such as four 16 K-byte banks or two 32 K-byte banks or one 16 K-byte bank and one 48 K-byte bank, etc, all of which are software selectable. In addition, the four banks should be independently addressable on the four 16 K boundaries: hexadecimal 0000, 4000, 8000, and C000. A much more simplistic approach is to bank-select the entire memory board, the bank size then being determined by the size of the memory on the board.

Other important features that a bank-selectable memory board

should have include the ability to decode any of the possible 256 I/O port addresses and have up to eight banks of memory for each port address. In addition, the user should be able to turn on or off any of the switchable banks when a system reset occurs. One last feature, which can be very valuable when troubleshooting a system with more than one 64 K-byte bank-selectable memory board, is an LED (light-emitting diode) indicator for each bank of memory that is being accessed. The flashing pattern of the LEDs can indicate where a problem is.

Waiting On Delivery of ADECLA120?

Avoid the hassle by upgrading your LA36 for 1200 baud operation with a DS120 Terminal Controller.

The Datasouth DS120 gives your DECwriter® II the high speed printing and versatile performance features of the DECwriter® III at only a fraction of the cost. The DS120 is a plug compatible replacement for your LA36 logic board which can be installed in minutes. Standard features include:

•RS232 interface

• 165 cps bidirectional printing •Horizontal & Vertical Tabs •Page Length Selection •110-4800 baud operation •1000 character print buffer •X-on, X-off protocol •Self Test

•20 mA Current Loop interface

•Top of Form

•Adjustable Margins

•Double wide characters

•Parity selection

•Optional APL character set

ti b-S J» *•§#

Over 4000 DS120 units are now being used by customers ranging from the Fortune 500 to personal computing enthusiasts. In numerous installations, entire networks of terminals have been upgraded to take advantage of today's higher speed data com-_ munications services. LSI microprocessor electronics and strict quality control ensure dependable performance for years to come. When service is required, we will respond promptly and effectively. Best of all, we can deliver immediately through our nationwide network of distributors. Just give us a call for all the details.

DATASOUTH COMPUTER CORPORATION

4740 Dwight Evans Road • Charlotte, North Carolina 2S210 • 704(5236500

jjgUiffij^M^Q1

One last word on bank-selectable memory is that a well-designed board will allow the user to work correctly with the slightly different approaches taken by the main manufacturers of multi-user systems: Alpha Micro, Cromemco, North Star, and Digital Research. (Digital Research only supplies the multi-user operating system, MP/M.)

Common Features

There are several other important features that are common to both single-user- and multi-user-optimized memory boards that the system designer should look for. The most important feature is the ability of the memory board to work with as many different processor boards as possible. This includes the standard 8080A-, Z80A-, and 8085-based boards, as well as the more advanced 16-bit machines (such as Alpha Micro and Marinchip's M9900).

This would not seem to be a major problem since all products manufactured for the S-100 bus should work with one another. However, in the real world this is not always the case. The S-100 bus started with and was defined around the 8080 microprocessor. As other microprocessors made their way onto the S-100 bus, they had to emulate the timing of the 8080. Each company came up with its own version for this timing. As a result, it is difficult to find two Z80A boards that generate their S-100 signals alike.

This creates a challenge to the dynamic-memory board manufacturers to come up with a flexible internal-timing scheme that allows the memory-timing circuits to adjust to the differences in the processor boards. The best way to achieve this is to use a minimum number of the S-100 bus-timing signals and, if at all possible, to avoid the use of the pSYNC signal. This one signal has created more problems than any other due to the many different processor-board designs manufacturers have come up with. The best designed dynamic-memory boards will correctly interface with the vast majority of the different board types available today, but no single dynamic-memory board can claim to work with them all.

Most of today's dynamic-memory boards use transparent (or invisible) refresh. A window in the processor timing is found where the memory

146 February 1981 © BYTE Publications Inc

Circle 96 on inquiry card.

MICROBYTE INTRODUCES

PROFIT FOR YOUR BOTTOM LINE

4 PORT I/O

•Quad RS-232C Serial Ports, One 20mA Current Loop Port

• Fully IEEE S-100 Bus Compatible

•Asynchronous Communications with Z80A-Dart(TM) or

Synchronous Communications with Z80A-SIO/0(TM) •Full Set of Modem Control Signals, including Rl (Ring Indicator) •Easily Configurable to Any Type of Terminal Interface •I/O Servicing Environments: (1) Polled; (2) Bus Vector;

(3)Z80 Mode 2 Vector

•Off-Board Interrupt Daisy Chain Capability •Special Receive Conditions: (1) Framing Error; (2) Parity

Error; (3) Receiver Overrun Error

•Baud Rates Selected Individually from 50 Baud to 300K Baud •72 Hour Burn-In

imimimiiiiiiiiiiHiiiiimiimmmigmii

Z-80A/I-0

•A complete single board Z-80A CPU with serial/parallel interface •Fully compatible with the proposed IEEE S-100 Bus Standard •Z-80A CPU (4MHz version of the Z-80) •158 instructions—superset of and upward compatible from the

8080's 78 instructions •Up to 4K of on board Eprom with optional Z-80 monitor program —

1K(2708), 2K(2716) or 4K(2732) •Full vectored interrupt capability •2MHz or 4MHz operation is jumper selectable •Selectable auto-wait state insertion for extending M1", MREQ*,

IORQ* and/or on board ROM •Dual RS-232 serial I/O ports using the Z80A-DART with individual

baud rate selection (16 baud rates from 50-19,200 baud) •Up to 24 bit parallel I/O port—fully programmable Intel 8255A •Up to 8 separate counter/timers using 2 Z-80A CTC i n

MICROBYTE

1198 E. Willow St., Signal Hill, CA 90806 • (213) 595-8571

D Please send me information on becoming a Microbyte dealer.

I

. DPIease send info on the Microbyte

I

I

I Name

Address. City

DISK CONTROLLER

•DMA to within 16M byte of memory

•State-of-the-art NEC765 LSI Controller

•IEEE-S100 compatible

•DMA arbitration allows use of multiple boards within a system

•PLL data recovery for totally reliable operation

•Write pre-comp switched at mid-disc for reliable double density

operation

•Supports up to four (4) drives •Power On, Power Off or Reset deselects drives to avoid

damaging files

•Drive deselect Time Out, deselect drives not in use •Single or double sided operation •Single density/double density operation •8" standard drives •Separate Vcc supply for data recovery to eliminate possible noise

problems

.State.

Zip.

i

64K DYNAMIC RAM BOARD

•Fully S-100 bus compatible/Alpha Micro compatible

•64K x 8 bit dynamic RAM

•Low power: + 8VDC @ 700 ma

4- 16VDC @ 100 ma

- 16VDC @ 25 ma •Built-in-parity with LED indicator and vector interrupt •Memory addressable in four 16K banks •Hidden refresh

•Gold contacts for high reliability •72-hour Burn-in

•Memory mapped via DIP switch •Built-in programmable write-protect •Programmable control port for parity and bank control

It takes more than an initial low price to make an S-100 board a profit generator for a dealer. It takes a total value cluster from the manufacturer — a value cluster that includes:

• Products •

• Price *

• Quality •

• Pre-sale Service •

• Post-sale Service •

• Commitment • MICROBYTE has the products — from memory boards to complete S-100 systems, and weoffer the rest of the value cluster — call today for the whole story on how you can become a Microbyte dealer.

Circle 97 on inquiry card.

BYTE February 1981 147

read and write operations are not being executed, thus allowing a refresh operation to take place without requiring the processor to wait. The result is that the system is not slowed down by the necessary refresh cycles. A different type of refresh must be done whenever the RESET or pWAIT (S-100 bus) signals are active for any extended period of time (more than several tens of microseconds). These conditions occur whenever the system-reset switch is activated or whenever a disk access to certain disk controllers is being performed using a programmed I/O interface. Either of these conditions stops the processor

generated timing that is required by the memory board for transparent refresh. Thus, the occurrence of either of these conditions must cause the memory board to enter an automatic refresh mode that continues until the processor again starts its generation of the timing signals.

Another feature that most memory boards incorporate is the use of the PHANTOM signal from the S-100 bus. This allows read-only memory on the disk controller or other board to overlay the system programmable memory to load an initial program from disk.

Other features to look for include

input filters on the address and control lines followed by Schmitttriggered input gates. This minimizes the false starting of memory cycles due to noise on the bus signals. Good logic design also dictates the use of clocked-logic or precision-delay lines for the generation of internalmemory timing, but under no circumstances should RC (resistor/ capacitor network) circuits be used between logic gates to generate delays. Products using this technique are unstable under many operating and manufacturing conditions and can only cause eventual trouble. One other important requirement

INTRODUCING 24-HOUR

When you need a program and you need it II The Software Express Service.

WEsnco

Where can you get the mostwanted microcomputer programs? How can you tell which ones are best for you? How can you get instant service on programs for word processing, accounting, budgeting, engineering, inventory control, patient management... and more?

You can place an order right now. Simply dial-up Westico's 24-hour computer (300 baud). Ask for a quick review of program descriptions and place your order immediately.

We're a new, high speed service staffed with technical experts who can provide programs for individuals and companies who are serious about the business of microcomputing. After you've acquired your program, our technical service and support team will remain just a phone call away.

searching for programs and still not find the one that's right for your particular needs. Or, you can order the perfect program from The Software Express Service. We've tried and tested hundreds of programs. We have what will work for you — whether you're a doctor, lawyer, accountant, engineer, scientist, surveyor, store owner, manufacturer, dealer, consultant or programmer.

Take advantage of Westico's 24Hour Software Express Service to any town or city covered by Federal Express, U.S. Express Mail, or other 24-hour delivery service. Simply dial-up our computer, call us or send a Telex and your program will be sped to you overnight. For regular service, you'll receive your program promptly by UPS. In the age of the computer, it shouldn't take ages to

get what you want.

WESTICO

You could lose valuable time

The Software Express Service

25 Van Zant Street ■ Nonualk, Connecticut 06855 (203) 853-6880

of dynamic-memory boards is good documentation. This should include board set-up documentation, detailed theory of operation, schematics, timing diagrams for the different processor-board types, a parts list, a board-layout drawing, and applications notes.

Finally, the dynamic-memory board should be backed up by the manufacturer through both guarantee and applications support. Several of the available memory boards come with a full one-year guarantee. The manufacturer should also be able to support the product with the necessary applications information to

determine if it will work in your particular system.

Limitations of Dynamic Memories

Although dynamic memory usually represents the best cost/performance ratio, there are several limitations that may prevent it from functioning correctly. The system designer should investigate these cases with the memory-board manufacturer before deciding to use a product.

It should be apparent from the above discussion that not all dynamic-memory boards will work with all processor boards. Only the

manufacturer can tell you if the memory board has been tested with the particular processor board you are planning to use.

Another troublesome area is in interfacing with DMA controllers. Generally, the problems arise from two different sources. First, the actual timing required from the DMA controller will vary depending on the particular memory board used. Not all memory boards use the same S-100 bus signals, thus complicating the DMA interface. If this timing is not compatible, then the memory read or write cycles will not function correctly.

SOFTWARE EXPRESS SERVIC

CP/MJ" programs tor TRS-80 Model II, Vector Graphic, iCom, Cromemco, North Star, Mlcropolls, Ohio Scientific and more.

Irelone* menls

GENERAL LEDGER Peachlree ACCOUNTS RECEIVABLE Peachlree ACCOUNTS PAYABLE Peachlree INVENTORY CONTROL Peachlree PAYROLL Peachlree CLIENT WRITE-UP Peachlree PAS-3 MEDICAL Artificial Int. PAS-3 DENTAL Artificial Int. PROPERTY MANAGEMENT Peachlree

PTA Asyst Design ESQ-1 Legal Micro Info. ESQ-1 Legal Demo Micro Info. DATEBOOK Organic

WORDMASTER MicroPro WORDSTAR MicroPro WORDSTAR MAIL-MERGE MicroPro WORDSEARCH Keybits TEXTWRITER Organic

MINIMODEL Financial Plan. STATPAK NW Analytical

ASCOM DMA

CBS DMA

MAGSAM IV Micro Appl. SELECTOR IV Micro Ap. Inc. PRISM/IMS Micro Appl.

BASIC-80 Microsoft BASIC COMPILER Microsoft S-BASIC Micro Ap, Inc. NEVADA COBOL Ellis PL/l-80 Digital Research CBASIC Compiler Systems PASCAL/M Sorcim PASCAL/MT+ MT Microsystems

$550

$40

A.D.I.L

550

40

A,D,I,L

550

40

A.D.I.L

650

40

A,D,I,L

550

40

A,D,I,L

990

40

A.D.I.L

500

40

A,C,I

500

40

A.C.I

990

40

A.D.I.L

595

40

A,C.I

1495

50

A.C.I.L

75

50

A.C.I.L

295

25

A.I.O

145

25

A.K.L

450

40

A.F.K.L

575

40

A.F.K.L

195

40

A.F

125

20

A,F

495

50

A.C.I.L

500

40

A.D.I

125

10

A.T

395

40

A.F.K

295

25

A.C.F.K

395

25

A.C.G.K

495

55

A.C.F.K

325

25

A.F.L

350

25

A.F.L

295

25

A.F

150

25

A

500

35

B.F.L.P

120

15

A

175

20

A.G

250

30

A

SUPERSORT I MicroPro SURVEYOR Peachlree

$225 550

$25 40

A.L A.D.I.L

All software has specific requirements for proper operation such as computer type, equipment configuration and support software.

Check the following codes for system requirements to be certain yoursystem will accept the software offered.

(A) CP/M version 1.4 or higher.

(B) CP/M version 2.0 or higher

(C) CBASIC-2.

(D) MBASIC version 4.51.

(E) BASIC-80 version 5.0 or higher.

(F) 48K memory or greater.

(G) 56K memory or greater. (H) 64K memory

(I) Business system: 48K memory. 200K dual disk drives, cursor addressable terminal, and 132 column printer. (K) Cursor addressable terminal. (L) signed license required for shipment. (O) specify 8080. Z80, or CDOS. (P) give CP/M serial number. (T) serial port and modem. (Z) Z80CPU.

Choose any of 4 ways to order:

• Write Westico, Inc., 25 Van Zant Street, Norwalk, CT 06855.

• Call (203) 853-6880.

• Telex 643-788.

• Dial-up our 24-hour computer (300 baud) (203) 853-0816.

Specify prepaid, COD., Master Charge, or VISA. (Please give credit card number and expiration date.)

Specify disk format: North Star Single or Double. Micropolis Mod I or Mod II; 8" single density, or Ohio Scientific.

Prices do not include shipping and COD. In CT add 7%% sales tax.

'Manual price will be credited against later purchase ol software.

CP/M is a trademark ol Digital Research 280 is a trademark ol Zilog, Inc. PASCAL/M is a trademark of Sorcim PASCAL/MT+ is a trademark of MT Micro Systems PEACHTREE is a trademark ol Retail Sciences. Inc. S-BASIC is a trademark ot Topaz Computing SELECTOR IV is a trademark ol Micro-Ap. Inc.

Copyright * 1981 Westico. Inc.

Data Terminals Fast ...from MICRON!AIL

DIABLO

630

The Diablo Model 630 is a reliable, high quality, fullcharacter serial printer (or anyone who is seeking superior print quality at a low cost. This is the first Diablo printer to offer complete interchangeability between metal and plastic print wheels. And the sophisticated and discerning user does not sacrifice printquality to obtainthis versatility. Every aspect of the Diablo 630 design has been focused on maintaining outstanding print quality. Terminals also have self-test extensive internal diagnostics and automatic bidirectional printing.

$1,999.00

Adjustable Forms Tractor — S200.00

ANADEX

DP-9500/9501

The Anadex Models DP-9500 and DP-9501 Alphanumeric Line Printers are designed for all printer applications, including those requiring high density graphics. Standard features include three standard interfaces (RS 232C, Centronics Parallel, and Current Loop), software selectable print sizes including compressed and expanded print, heavy-duty nine-wire printhead (permits true underlining and descending lower case letters), and fast bi-directional printing. The model 9501 oilers slightly higher graphics resolution and a slightly slower print speed than the model 9500.

$1,399.00

PRINTERS

C.RT/S

TELEPRINTERS

ANADEX

DP9000 T.I.

$1299

810/2 DIABLO

$1599

TeleVideo

912C

920C

950

SOROC

$ 725 $ 795 $ 995

DEC

LA 34 LA34AA

DIABLO

$ 969 $1099

1640RO 1650RO

$2525 $2675

IGL120 10.140 IQ.135

$ 689 $1099 $ 895

1640KSR 1650KSR

$2830 $2940

TELETYPE

43

Quiet, compact and lightweight, this 30 character-persecond matrix teleprinter belongs wherever reliable performance and quality print-out are required—in the office, factory, classroom, or laboratory. Print quality is exceptionally crisp and easy to read. What makes the model 43 so outstanding is its total economy—it costs less to own because of reliable low-cost LSI (Large Scale Integration) circuitry used to carry out functions rather than more expensive, less reliable mechanicalhardware.Buy now at this special price and beat the announced Teletype price increase.

Price good throughMarch 3L 1981

$989.00

cMICRDMfl.L.,

MICROMAIL • BOX 3297 • SANTA ANA, CA 92703 (714) 731-4338

To Order: Send check to MICROMAIL. P.O. Box 3297, Santa Ana, C A 92703. Personal or company checks require two weeks to clear. Visa/MasterCard accepted. C.O.D. requires a 15% deposit. Handling: Add 3% to orders less than S750. 2% to orders S751 ■ S2.000. 1% to orders over S2.000. NOTE, Handling charges are waived on orders prepaid in advance by check. Shipping: We ship FREIGHT COLLECT via UPS or Motor Freight. Air and Expressdelivery is available.

The second trouble area involves the correct refreshing of the memory. The majority of the dynamic-memory devices used today are the 4116-type, which require 128 refresh cycles every two milliseconds. This requirement is easily met when the processor controls the bus and the memory board uses transparent refresh. However, when the DMA controller takes over the bus, most memory boards will cease to do refresh cycles. If the DMA controller has access to the bus for a small number of byte transfers, this does not present a problem.

A problem may exist, however, when the DMA controller does a burst sector or track transfer. This may prevent refresh from occurring for too long a time interval, causing the memory to lose data. Some DMA controllers, particularly hard-disk controllers, avoid this problem by doing the DMA transfer to an onboard sector buffer consisting of static memory. Memory or I/O move instructions are then used to transfer the data in this memory to the system memory. Again, it is important to check with the memory-board manufacturer for compatibility with the DMA controller you plan on using.

One last area of concern involves interfacing with a front-panel type of system. Extra circuitry is required for a dynamic-memory board to correctly work with the front-panel functions such as examine, deposit, and run. Many memory-board manufacturers do not include this necessary circuitry so that they may add other functions that they think are more valuable in their intended marketplace. If you need this function, check with the memory-board manufacturer.

In summary, the dynamic-memory board represents a superior cost/performance ratio when compared to static memories. When looking at dynamic-memory boards, choose one that is optimized for your particular application, whether it be a singleuser or multi-user system. It is also a good policy to check with the memory-board manufacturer before your purchase to verify that the board will work correctly in your particular system. You are best protected by a good return policy in case you experience any problems after testing the memory board. ■

150 February 1981 © BYTE Publications lnc

Circle 98 on inquiry card.

The first personal computer far under $200.

The Sinclair ZX80. A complete computeronly $199. 95 plus $5.00 shipping.

Now, for just $199.95, you can get a complete, powerful, full-function computer, matching or surpassing other personal computers costing several times more.

It's the Sinclair ZX80. The computer that "Personal Computer World" gave 5 stars for 'excellent value.'

The ZX80 cuts away computer jargon and mystique. It takes you straight into BASIC, the most common, easy-to-use computer language.

You simply take it out of the box, connect it to your TV, and turn it on. And if you want, you can use an ordinary cassette recorder to store programs. With the manual in your hand, you'll be running programs in an hour. Within a week, you'll be writing complex programs with confidence.

All for under $200.

Sophisticated design makes the ZX80 easy to learn, easy to use.

We've packed the conventional computer onto fewer, more powerful LSI chipsincluding the Z80A microprocessor, the faster version of the famous Z80. This makes the ZX80 the world's first truly portable computer (6V2" x 8V2" x \W and a mere 12 oz.). The ZX80 also features a touch sensitive, wipe-clean keyboard and a 32-character by 24-line display.

Yet, with all this power, the ZX80 is easy to use, even for beginners.

""••AaCft^m

Your course in computing.

The ZX80 comes complete with its own 128-page guide to computing. The manual is perfect for both novice and expert. For every chapter of theory, there's a chapter of practice. So you learn by doing—notjust by reading. It makes learning easy, exciting and enjoyable.

You'll also receive a catalog packed with items that can make your ZX80 even more useful. Including 27 program cassettes, from games and home budgeting for just $6.95, to Sinclair's unique Computer Learning Lab. And books, hardware options and other accessories.

ZX80's advanced design features.

Sinclair's 4K integer BASIC has performance features you'd expect only on much larger and more expensive computers. ■ Unique'one touch'entry. Keywords

(RUN, PRINT, LIST, etc.) have their

own single-key entry to reduce typing

and save memory space.

■ Automatic error detection, A cursor identifies errors immediately to prevent entering programs with faults.

■ Powerful text editing facilities.

■ Also programmable in machine code.

■ Excellent string handling capability—up to 26 string variables of any length.

■ Graphics, with 22 standard symbols.

■ Built-in random number generator for games and simulations.

Sinclair's BASIC places no arbitrary restrictions on you—with many other flexible features, such as variable names of any length.

And the computer that can do so much for you now will do even more in the future. Options will include expansion of IK user memory to 16K, a plug-in 8K floatingpoint BASIC chip, applications software, and other peripherals.

Order your ZX80 now!

The ZX80 is available only by mail from Sinclair, a leading manufacturer of consumer electronics worldwide.

To order by mail, use the coupon below. But for fastest delivery, order by phone and charge to your Master Charge or VISA. The ZX80 is backed by a 30-day moneyback guarantee, a 90-day limited warranty with a national service-by-mail facility, and extended service contracts are available for a minimal charge.

Price includes TV and cassette connectors, AC adaptor, and 128-page manual.

All you need to use your ZX80 is a standard TV (color or black and white). The ZX80 comes complete with connectors that easily hook up to the antenna terminals of your TV. Also included is a connector for a portable cassette recorder, if you choose to store programs. (You use an ordinary blank cassette.)

The ZX80isa family learning aid. ChildrenlOand above will quickly understand the principles of computing—and have fun learning.

Master Charge or VISA orders call:

(203) 265-9171. We'll refund the cost of your call. Information: General and technical—(617) 367-1988, 367-1909, 367-1898, 367-2555. Phones open Monday-Friday from 8 AM to 8 PM EST.

Sinclair Research Ltd., 475 Main St., P.O. Box 3027, Wallingford, CT 06492.

To: Sinclair Research Ltd., 475 Main St., P.O. Box 3027, Wallingford, CT 06492.

Please send me ZX80 personal computer(s) at $199.95* each (US dollars), plus $5

shipping. (Your ZX80 may be tax deductible.)

I enclose a check/money order payable to Sinclair Research Ltd. for $

Name_

Address _ City

.State.

_Zip_

Occupation:

Intended use of ZX80:.

-Age:

L

Have you ever used a computer? □ Yes □ No. *For Conn, deliveries, add sales tax.

Do you own another personal computer? □ Yes □ No.

BY-2-1

Stacking Strings in FORTH

John ) Cassady

339 15th St

Oakland CA 94612

Anyone who is familiar with writing programs in BASIC and who later switches to writing in FORTH surely misses the convenience and ease of BASIC string handling. Fortunately, there is no need to deprive yourself all these features: they can be implemented in FORTH with the additional bonus of not being tied to the preconceived ideas of your software vendor. If you do not like the way the string operators work, you can change them: you control the source code.

Adding Strings to FORTH

Tools for manipulating strings of characters and other data items are useful to the personal computer programmer. The routines presented here are an extension to FORTH. They run in fig-FORTH (the versions of FORTH for various microprocessors written by the FORTH Interest Group) and should run with little adaptation in any standard FORTH.

String implementations abound in FORTH. Some, like the one presented here, use stacks. The use of stacks seems appropriate in FORTH. Most of FORTH programming consists of manipulating entities on various stacks.

A stack is a LIFO (last in, first out) list. Stacks usually have a fixed width; that is, the number of bits that are simultaneously pushed (ie: put onto the stack) or popped (ie: taken off the stack) does not vary. An item on the stack is usually limited to some maximum size (eg: 16 bits) that can

represent numbers up to decimal 65,535. The FORTH parameter and return stacks both have fixed widths. The string stack is like the parameter stack and the return stack, but it is not restricted in width. Stringstack items can be any width and any combination of widths. However, item size and total stack size are limited only by the amount of memory devoted to them. As a rule of thumb, a few hundred bytes are more

than enough.

Figures 1 and 2 and listing 1 illustrate two ways of visualizing string stacks. They show the stacks growing downward from high memory. This is typical in FORTH. Even though the string stack grows downward, we will refer to the most recent entry on the stack as the top of the stack. The unchanging end of the stack (hexadecimal 2000 in figure 2) will be called the base. When something is popped

r~

0

6

W

1

N

T

E

R

r -1

(

GROWS DOWN

N

\

FIXED BASE OF STRING STACK $0

0

4

F

A

L

L

(

^

r~

0

6

s

U

M

M

E

R

-J

(_

/■

0

6

s

P

R

1

N

'

\

HED

E.

\ \

1

<

1 L

NEXT ITEM PUS WOULD GO HER

ON

ST*

-J

;

CK

THIS ITEM WOULD BE PRINTED BY THE FORTH WORD {$.}

Figure 1: One implementation of a string stack in FORTH. As the name implies, a string stack is a stack of variable-length strings (as opposed to fixed-length numbers) organized such that only the string most recently put on top of the stack can be removed from the stack. Each stack entry consists of the length of the string, expressed in 2 bytes, followed by the characters of the string itself. Due to an initial design decision, this string grows toward low memory locations (ie: down) rather than toward high memory locations (ie: up). Despite this physical orientation, the most recently placed string is located at the top of the stack — at the lowest address in the stack.

152 February 1981 © BYTE Publications Inc

"My computer helped me write

The Final Encyclopedia. I wouldn't trust

anything less than Scotch" Brand Diskettes

to make a long story short!'

Gordon R. Dickson, Science Fiction Author, Minneapolis, Minnesota

Gordon Dickson: a small businessman whose product is his own imagination. He's written more than 40 novels and 150 short stories; his newest work is The Final Encyclopedia. He uses his personal computer and word processing software to maximize his production. All his words-his productare stored on diskettes. He calls up sentences and paragraphs on demand, and gets more rewrite out of the time available. So he depends on Scotch diskettes to save himself production time. Dependable Scotch media can work just as hard foryou. Each Scotch diskette is tested before it leaves our factory, and certified error-free. So you can expect it to perform exactly right. Scotch 8" and 5Va" diskettes are compatible with computer/diskette systems like TRS-80, Apple, PET, Wang and many others. Get them from your local 3M distributor. For the one nearest you, call toll-free: 800/328-1300. (In Minnesota, call collect: 612/736-9625.) Ask forthe Data Recording Products Division. In Canada, contact 3M Canada, Inc., Ontario.

If it'sworth remembering,

it's worth Scotch

Data Recording Products.

cfete

3M Hears You...

3M

Circle 99 on inquiry card.

BYTE February 1981 153

Circle 100 on inquiry card.

from the stack, it is the top item (as defined above) that is removed.

A string consists of a 2-byte length word followed by the text of the string, as you are moving upward in memory. Since the length is explicitly stated, there is no need for a separator or delimiter. Any of the 256 possible 8-bit quantities, for example, can appear in the string. Strings can

include binary numbers, floatingpoint numbers, encrypted messages: in short, anything that can be stored in a byte.

Before considering routines any further, heed the caution that this article presents an example of an extension to FORTH. It's not the only way to implement strings nor, perhaps, the best way. The article

7 7

$0 ►

TEXT <

LENGTH

TEXT I

LENGTH

TEXT (

LENGTH

TEXT I

LENGTH

(2 BYTES OR 1 FORTH WORD)

ASSUME MEMORY ADDRESS 2000

//

-MEMORY ADDRESS 19E2

Figure 2: Another view of the string stack of figure 1. $0isa constant that points to the address of the base of the string stack. Here it has the value of hexadecimal 2000. See listing 1 for the FORTH dialogue that uses the string stack shown here.

154 February 1981 © BYTE Publications Inc

ITION

VERS

MM

:

'■

The Byte Covers shown at left are available as Collector Edition Prints. Each full color print is:

• 11" X 14" including a 1Vz" border.

■ Part of an edition strictly limited to only 100 prints.

• Personally inspected, signed and numbered by the artist, Robert Tinney.

• Accompanied by a Certificate of Authenticity.

• Carefully packed and shipped first class.

• Priced at $20, plus $3 ($6 overseas) for postage and handling. If Set 1-4 or Set 5-8 is ordered, the price for all 4 prints is only $70.

To order, use the coupon below. Visa or MasterCharge orders may call Toll Free.

Please send me the following Collector Edi tion Byte Covers and Certificates of Authen ticity.

Qty. Cover Amount

#1-7 Bridges of Konigsberg $20

#2-Fun and Games $20

#3-Homebrev» $20

#4-Sottv»are Mirage $20

#5-Computer Engineering $20

#6-Total Eclipse $20

#7-Computer Hardware $20

#8-Perspectives $20

No.s 1-4 $70

No.s 5-8 .$70

Post. & hand. ($3 in US . $6 overseas) S

Total

D I have enclosed check or money order

□ Visa □ MasterCharge

Card #

Expiration Date

Send my print(s) to:

Name

Address

City

State_

-Zip

I

F°^s7^nr—---_ 708' '-80o-<*«-ose^EE!

Mail this coupon to:

robert tinney graphics

1864 N. Pamela Dr. Baton Rouge, LA 70815

simply illustrates a FORTH program and an interesting mixture of two quite distinct logical structures: the stack and the string. And it has some desirable features: it is easy to visualize and modify the operations.

Some String-Manipulation Words

In listing 2, the word *$* creates a constant with a value equal to the size of memory to be reserved for the string stack during compilation. The stack size can be changed simply by changing this one value and recompiling.

The words $0 , $P , and { $P! } are

direct duplicates of the words SO , SP , and { SP! } used in the FORTH kernel. The only difference is that they operate on the string stack instead of on the parameter stack. $0 is a constant that returns the address of the fixed end of the string stack (ie: the base) to the parameter stack. (See line 4 of listing 2.) This means that the value of $0 , the memory address, is pushed onto the parameter stack when it is used.

$P is a variable. It is the stack pointer. At any given time, it contains the address of the top string on the stack (which is the length word of

* WRITE OR CALL FOR FREE CATALOGUE *

CALIFORNIA COMPUTER SYSTEMS

HIGH IN QUALITY. LOW IN PRICE Z80 CPU. 4 Mhz, with one serial port: 12 slot S-100 mainframe, disk controller, 64K

Dynamic Ram, CIVM 2.2s Si,645.

Interfaced to 2 Shugart, 8 inch drives with power supply and cabinet for an

additional Si,250.

and you have a complete S-100 system for under $3,000. THE BEST BUY ON THE MARKET.

IMS 5000 and 8000 Systems

The new rising stars! Beautifully designed and constructed with the Industrial Micro System reputation for fine quality. These systems feature a Z80 CPU, S-100 bus; double density drives (either single oi" double sided) CP/M'HI. 5000 series uses mini floppies, 8000 uses maxi floppies. Hard disk and MP/M now available.

Model 5-00125 with two double density drives, 32K Static RAM $2,765.

Model 8-00125 as above but with 8" drives $4,185.

PER SCI—THE KING AND QUEEN OF DRIVES!

Model 299B: Dual headed drives, total 3.2 MB unformatted $2,300.

Model 277: Dual 8 inch drives, voice coil positioned, IBM compatible,

1600 K BYTES per drive, unformatted $1,210.

Slimlinecabinet and power for either 277or299 $ 300.

DRIVES Dual 800R Shugarts, supply, cabinet and fan, A & T. . Qume data track 8, double sided,

supply, fan cabinet, A & T

Per Sci 277.Si,210. Shugart . . MPIB51 S265. B52

power $1,250. power $1,625. . $525. . $365.

HAZELTINE 1500

1510 $980. 1520

1420 (two year warranty)

. . $885. $1,210. . . $775.

CENTRONICS

737 S780. 730 $680.

Apple serial/parallel interface . . . .$195.

TELEVIDEO SMART CRTs 912 S780. 920

.$850.

IMS MEMORY 16 K static $285.

32 K static $585.

64 K Dynamic with parity $950.

TEI MAINFRAMES, S-100

12 slot $500.

22 slot $670.

TARBELL

Double density controller $420.

Cables $40.

3M SCOTCH® Diskettes

buy the best. 8" or 5" (Model 740 or 744)

One box of ten diskettes $29.

Five boxes, each $26.50

WE EXPORT:

Overseas Callers:

TWX 710 588 2844

Phone 212 448-6298 or Cable: OWENSASSOC

SHE OUR AD FOR 8" FLOPPY NORTH STAR SUBSYSTEM ON PAGE 326

JOHN D. OWENS

Associates, Inc.

12 Schubert Street

Staten Island, New York 10305

212 448-62831 212 448-2913 212 448-6298

the top string). When $P is executed, it places the address (not the value) of the stack pointer onto the parameter stack. Therefore, to get the value of the string-stack pointer, we need to type the following two-word sequence:

$P @

This sequence is reduced to a single word $P@ , which is defined at line 7 of listing 2. Listing 3 shows a FORTH dialogue that explains the use of VARIABLE , CONSTANT , and @ (pronounced "fetch").

The word { $PI } empties the string stack. [The braces used in { $P! } and elsewhere in the article are not part of the FORTH word. Following a convention set in the August 1980 BYTE, braces are used to surround a FORTH phrase or a FORTH word that contains a punctuation mark GW] It does this by

placing the value for the base of the string stack onto the parameter stack and making it the current value for the string-stack pointer. The word { $PI } is the first colon definition encountered. The words CONSTANT , VARIABLE , and { : } compile words into the FORTH dictionary.

Our next definition, in line 8 of listing 2, is $DROP . This will drop (ie: delete) the string on top of the string stack. It may seem we are getting ahead of ourselves — after all, we are defining $DROP before we define any word that puts strings onto the string stack. But this is okay as long as we don't use any undefined words inside the definition. FORTH compiles its words in one pass, and it won't give us an error message as long as we don't give it a word it doesn't recognize.

If we "walk" through $DROP , we see that the value of the string-stack pointer is placed on the parameter stack by the word $P@ . It is then duplicated by the word DUP , leaving two copies. The top copy of the address is replaced by the contents of the location pointed to when the word @ is executed. This places the length of the top string on the parameter stack. The word + adds this length to the value of the stack pointer, and 2+ increments that result by 2. The value on top of the parameter stack is now the address of the word containing the length of the second string on the string stack.

156 February 1981 © BYTE Publications Inc

The sequence { $P ! } is a two-step process that places the address of the variable containing the string-stack pointer on the parameter stack and storing the new value into it. Thus, after executing $DROP , the stringstack pointer is changed to point to what was the next-to-top string. This effectively drops the top string, even though there was nothing changed in the contents of the memory buffer devoted to the string stack.

This definition of $DROP is not entirely adequate. If you execute this word with an empty string stack, there is a good chance of moving your string-stack pointer into a memory area where it doesn't belong. To avoid this, additional code must be added. The word $DROP should check that the stack is not empty before it executes. Safeguards of this nature are appropriate in many of these routines. To include them in this article would, however, needlessly complicate the description of the words.

Loading, Storing, and Printing Strings

The word $@ (line 9 of listing 2) is the first that expects parameters on the parameter stack. It expects a text address as the second stack item and a quantity on top of the stack. The text address points to a memory location of the first byte of the string that will be moved to the string stack. The quantity is the length of the string. Thus, if the expression "the quick brown fox" was residing in memory starting at hexadecimal location 2C80 and we wanted to move it to the string stack, we would type the following sequence:

2C80 13 $@

with the hexadecimal 13 (or decimal 19) being the length of the string. The quantities could be in decimal if the FORTH word BASE has been set to decimal.

The word { $! } complements $@ . It takes the string on top of the string stack and moves its text to whatever memory location is addressed by the top of the parameter stack. Thus, the string can be moved into a string variable, to an output buffer, or to a memory-mapped video display.

To print a string we use the twocharacter word { $. } (pronounced "string dot"). This follows the

FORTH convention of using dot for output. It also uses the FORTH operator TYPE to accomplish it.

$DUP (line 13 of listing 2) is shown as an example of one of several operators that might be written to manipulate string-stack items. Useful additions are $SWAP and $OVER. The need could also arise for a $ROT , although I've never wanted it. $DUP simply gets the length and location of the current top string on the string stack and executes $@ .

For a truly useful system, we want a person to sit at a keyboard and be able to type a sentence directly to the

string stack. This and more is accomplished by the one-character FORTH word { " } (pronounced "quote"). The techniques used in quote are exactly the same as in the fig-FORTH message-handler word { ." }. This word (pronounced "dot quote") is a period followed by a double quote mark. This word checks to see if we are interpreting from the keyboard or compiling a definition. If we are interpreting, it accepts input until it detects another quote, then moves the text between the two quotes to the string stack. If we are compiling a

Text continued on page 162

TELETYPE MODEL 43 INVENTORY SALE

TELETYPE Model 4320 AAA S885.

220 volt model with transformer installed inside

cabinet .... S985.

Model 43ASR, 8 level, 1" tape S2,595.

Limited supply of Model 45 available.

IBM 3101 CRT Model 10 Sl,l95.

Model 20 Si,395.

Selectric-like, detached keyboard. 9x16 dot matrix. Maintenance contract from IBM only $70 per year.

ITHACA INTERSYSTEMS

Full S-100 IEEE Compatibility! Full 24 address bits. DMA disk controller. SYSTEM 2A includes20 slot mainframe with front panel, 64K Dynamic RAM. Z80 CPU, 4 MHZ, extended addressing capability. 4 parallel, 2 serial I/O, floppy controller. Our discounted price S3,236.

MARINCHIP SYSTEMS M9900

Elegant 16 bit CPU, S-100 compatible, multi user, multi processor operating system. BASIC, FORTH, META, PASCAL, Word processor, text editor

CPU kit and software package S 550.

Assembled S 700.

Complete system, 64KB, two drives 55,700.

MICROANGELO 52,280.

High resolution graphics system. Microangelo features 15", 22MHZ, green phospher screen, 72 key keyboard; includes complete cabling and software. From SCION. S-100 Graphics card 5960.

GRAPHICS SOFTWARE

On line, real time, for the M9900 to drive the Microangelo. For use in design of PC board masks, 1C masks and other applications.

CORVUS HARD DRIVES

We are the S-100 CORVUS dealer in the New York area. Demonstrations by appointment.

MODEL 11, HARD DISK SYSTEM 54,820.

Mirror Backup System S 715.

Host Multiplexer S 675.

MULTI-BUS

Z-8000 CPU and supporting boards. From Central Data Corp. Completesystemsstarting at 56,500.

INDUSTRIAL

MICRO

SYSTEMS

TELETYPE

HAZELTINE

IBM

TELEVIDEO

TEI

TARBELL

CORVUS

PER SCI

NEC

ITHACA

INTERSYSTEMS

MARINCHIP

DATA SOUTH

QUME CENTRONICS

TEXAS

INSTRUMENTS

ATARI

DEC

CALIFORNIA

COMPUTER

SYSTEMS

KONAN

EDGE

TECHNOLOGY

INNOTRONICS

XEROX

DIABLO

INTEGRAL

DATA SYSTEMS

CROMEMCO

SOROC MICROPRO

TELETEK

NOVATION

AMPEX

CDC

NORTH STAR

COMMODORE

SCION

MP!

POWER ONE

MEASUREMENT

SYSTEMS AND CONTROL

WE OFFER A FULL RANGE OF EXPERT CONSULTING

SERVICES COVERING ALL AREAS

OF COMPUTER APPLICATIONS AND SYSTEMS.

JOHN D. OWENS

Associates, Inc. SEE OUR AD ON FACING PAGE

February 1981 © BYTE Publications Inc 157

Circle 109 on inquiry card.

If you're looking for

the best prices in the U.S.A. on

TRS-80

MICROCOMPUTERS

We have consistently offered the TRS-80 line at savings up to 20%, which means you can save $150 to $1500 by buying directly from Computer Discount of America.

TRS-80 Model II, 64K System, with disc drive only $3385.00

Other TRS-80 Model II, or Model III computers and systems, Color Computers, and Pocket Computers are in stock at similar savings.

Our savings are as big on expansion interfaces, printers, disketteseverything for your TRS-80 System.

ATARI

MICROCOMPUTERS

We have the full line of ATARI personal computers and systems, including Models400 and 800. The computers, accessories, and hardware are brand new, in factory sealed cartons, and carry a full factory warranty. Most models are in stock for immediate delivery (usually within 7-10 days), and a price quote is as near as your phone. So if you're looking for the best prices in the U.S.A., for microcomputers and accessories, call Computer Discount of America, Inc., West Milford, New Jersey 07480. 201-728-8080. NO TAX ON OUT-OF-STATE SHIPMENTS.

TOLL FREE 800-526-5313

Computer

of America

Authorized TRS-80 dealer, store B-282.

Listing 1: Manipulating the string stack and string pointer. Figures 1 and 2 show the state of the string stack at the beginning of this dialogue. Here and in following listings, user input is underlined and computer response is not. See listing 3 for further details on the FORTH word @ (pronounced "fetch").

Dialogue With Computer HEX OK

$0 . 2000 OK

$P @ . 19E2 OK $P @ @ . 6 OK

%_ SPRINGOK

$0 . 2000 OK

$P @ . 19EA OK $P @ @ . 6 OK

t SUMMEROK S^FALLOK $. WINTEROK

Commentary

All numbers will be expressed as hexadecimal.

Base of string stack is hexadecimal 2000.

Location pointed to by stack pointer $P.

Contents of location (length word of string on top of stack).

Print top string; notice no space between STRING and prompt OK.

The base of the stack hasn't changed. (It's a constant.)

But the stack pointer has changed.

Print the next three strings, popping them from the string stack.

Listing 2: Defining string-manipulating words. See text for details.

0 1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

( FORTH STRING STACK EXTENSION HEX FORTH DEFINITIONS

FIGFORTH1.1 )

200 CONSTANT *$' *$* ALLOT ( LEAVE HERE CONSTANT $0 $0 VARIABLE $P $P! $0 $P ! $P@ $P @ ; $DROP $P@ DUP $@ DUP >R $P@

SWAP - SWAP $! DUP 2+ SWAP i $. $P@ DUP 2 + $DUP $P@ DUP

(NUMBER OF BYTES RESERVED FOR $STK

IN THE DICTIONARY OF *$' BYTES FOR $STK

( $0 RETURNS FIXED BASE OF $STK TO PSTK

$P RETURNS ADDR OF VAR HOLDING $STK PTR

( $P! EMPTIES $STK BY RESETTING $P TO $0

( $P@ RETURNS VALUE OF $P TO PSTK

(- 2+ $P ! ; ( DROP TOP STRING

TA - 2 QTY - 1 FETCH STRING TO $STK

R CMOVE 2 - R> OVER ! $P ! ;

SWAP CMOVE $DROP ; ( ADDR - 1

TYPE $DROP ; ( OUTPUT STRING @ $@ ; ( DUPLICATE STRING

GAP

( OVER ) ROT

SWAP @ 2+ SWAP

Listing 3: A dialogue that explains the FORTH words CONSTANT , VARIABLE , @ , and { . }. The main point to remember is that when you name a constant, its value is put on the stack; but when you name a variable, the address that contains the value is put on the stack.

Dialogue With Computer 100 CONSTANT CON OK

100 VARIABLE VAR OK CON OK

100 OK

VAR OK . 6480 OK

Commentary

Defining CON = 100.

Defining VAR = 100.

Put value of constant onto stack;

print value on top of stack, remove from

stack; therefore, 100 is value of CON.

Put address of variable onto stack; print value on top of stack, remove from stack; therefore 6480 is the memory location at which the value of VAR is stored.

Listing 3 continued on page 160

158 February 1981 © BYTE Publications Inc

Circle 101 on inquiry card.

SYBEX SPEAKS YOUR LANGUAGE . . .

THE PASCAL HANDBOOK by Jacques Tiberghien

— A dictionary of every Pascal instruction, function, operator and reserved word covering virtually all versions of Pascal. 300 pp., 150 III., Ref. P320, 7"x9", $14.95 ■ INTRODUCTION TO PASCAL (Including UCSD PASCAL) by Rodnay Zaks — A step-by-step introduction for anyone wanting to learn the language of PASCAL. Describes UCSD and Standard Pascals. 440 pp., 100 III., Ref. P310, 7"x9", $14.95 ■ INSIDE BASIC GAMES by Richard Mateosian — Uses a games format to teach program design in BASIC. Games run on TRS-80, APPLE II, PET/CBM and others. 300 pp., 100 111., Ref. B245, 7"x9", $13.95 ■ FIFTY BASIC EXERCISES by J.P. Lamoitier Teaches BASIC by actual practice using graduated exercises drawn from everyday applications. All exercises written in Microsoft BASIC. 300 pp., 140 III., Ref. B250, 7"x9", $12.95 ■ THE CP/M HANDBOOK by Rodnay Zaks - Complete instructions and reference handbook for CP/M

— the industry standard in microcomputer operating systems. 336 pp., 100 III., Ref. C300, WxWA", $14.95 ■ PROGRAMMING THE Z80 by Rodnay Zaks - A complete course in programming the Z80 microprocessor and a thorough introduction to machine language. 620 pp., 200 III., Ref. C280, SVi"x&Vi", 2nd Ed. $14.95 ■ PROGRAMMING THE 6502 by Rodnay Zaks Machine language programming of the 6502 from

basic concepts to advanced data structures. 392 pp., 160 III., Ref. C202, 5%"x8'/a", 3rd Ed., $12.95 ■

6502 APPLICATIONS BOOK by Rodnay Zaks Real life application techniques: the Input/Output book for the 6502. 288 pp., 207 III., Ref. D302, 5'/2"x8'/2", $12.95 ' ■

6502 GAMES by Rodnay Zaks — Third in the 6502 series. Teaches advanced programming techniques using games as a framework for learning. 304 pp., 140 III., Ref. C402, SVS'xBVi", $12.95 ■

YOUR FIRST COMPUTER by Rodnay Zaks - The most popular introductions small computers, what they do and how to buy one. 280 pp., 150 III., Ref. C200A, 5'/2"x8'/2", 2nd Ed., $7.95 ■

MICROPROCESSORS: FROM CHIPS TO SYSTEMS by Rodnay Zaks — Covers components, concepts and techniques from basic to advanced. 420 pp., 257 III., Ref.C201, 5'/2"x8'/2", 3rd Ed., $10.95 ■

MICROPROCESSOR INTERFACING TECHNIQUES by Austin Lesea, Rodnay Zaks — Hardware and software interconnect techniques including D to A conversion, peripherals standard buses and troubleshooting. 464 pp., 400 III., Ref. C207, SVi'xBVi", 3rd Ed., $15.95 ■

PROGRAMMING THE Z8000 by Richard Mateosian — Architecture and function of the Z8000 and its family of support chips. Includes programming in Z8000 machine language. 312 pp., 124 III., Ref. C281, 5'/2"x8'/2", $15.95 ■

fsYBE

MAIL TO: SYBEX

DEPT. B2^ _

2344 SIXTH STREET ^^^T BERKELEY, CA 94710 Phone Orders: 415/848-8233

NAME

ADDRESS. CITY

D SEND ME YOUR FREE CATALOG

STATE

ZIP

ADD □ $1.50/book UPS or □ 75«/book 4th class mail (CA add tax) OR CHARGE MY □ VISA DMC D AM EX. CARD NO

Total Amt. Enclosed.

SIGNATURE

. EXP. DATE.

Circle 102 on Inquiry card.

MTI stocks 'em all for faster delivery.

No hidden charges. Prices include delivery.

Ask about our"QED" discounts.

V ISA and MasterCard orders accepted.

VIDEO TERMINALS

VT100 DECscope $ 1695

VT132 DECscope 2295

ADM-3A (dumb terminal) •

ADM-3A+ (dumb terminal) »

ADM-31 (2 page buffer) •

ADM-42 (8 page buffer avail.) •

1410 (Hazeltine dumb terminal) 825

1420 (dumb terminal) 895

1421 (Consul 580 & ADM-3A comp.l.... 895

1500 (dumb terminal) 1045

1510 (buffered) _ 1145

1520 (buffered printer port) 1395

1552 (VT-52 compatible) 1350

300 BAUD TELEPRINTERS

LA34-DA OECwriter IV 1045

LA34-AA DECwriter IV 1295

Teletype 4310 1085

Teletype 4320 1225

Diabl.o 630 RO 2295

Diablo 1640 RO 3085

Diablo 1640 KSR 3285

Diablo 1650 RO 3185

Diablo 1650 KSR 3385

Tl 743 (portable) 1190

Tl 745 (portable/built-in coupler) 1585

Tl 763 (portable/bubble memory) 2690

Tl 765 (port/bubble mem/b-i coupler) . 2895

600 BAUD TELEPRINTERS

Tl 825 RO impact 1565

Tl 825 KSR impact 1645

Tl 825 RO Pkg 1750

Tl 825 KSR Pkg 1895

1200 BAUD TELEPRINTERS LA120-AA DECwriter III (forms pkg.) . 2410

LA 180 DECprinter I 2195

Tl 783 (portable) 1745

Tl 785 (port/built-in coupler) 2395

Tl 787 (port/internal modem) 2845

Tl 810 RO impact 1800

Tl 810 RO Pkg 2047

Tl 820 KSR impact 1895

Tl 820 KSR Pkg 1995

TI820 RO 1895

Tl 820 RO Pkg 2047

2400 BAUD

Dataproducts M200 (2400 baud) 2595

DATAPRODUCTS LINE PRINTERS

B300 (300LPM band) 5535

B600 (600LPM band) 6861

2230 (300LPM drum) 7723

2260 (600LPM drum) 9614

2290 (900LPM drum) 12655

ACOUSTIC COUPLERS

A/J A242-A (300 baud orig.l Z42

AM 247 (300 baud orig.) 315

A/J AD342 (300 baud orig./ans.) 395

A/J 1234 (Vadic compatible) 895

A/J 1245 (300/1200 Bell comp.l 695

MODEMS

GDC 103A3 (300 baud Bell) 395

GDC 202S/T (1200 baud Bell) 565

GDC 212-A (300/1200 baud Bell) 850

A/J 1256 (Vadic compatible) 825

CASSETTE STORAGE SYSTEMS

Techtran 816 (store/forward) .1050

Techtran 817 (store/for/speed up) 1295

Techtran818 (editing) 1795

Techtran 822 (dual) 2295

MFE 5000 (editing) 1495

FLOPPY DISK SYSTEMS

Techtran 950 (store/forward) 1395

Techtran 951 (editing) 1995

•Please call for quote.

mti

Applications Specialists & Distributors Great Neck. New York/Cleveland Ohio

N.Y.: 516/482-3500 & 212/89^-7177 800/645-8016 Ohio: 216/464-6688

Listing 3 continued:

VAR OK @ OK

_^100 OK

VAR @ . 100 OK VAR ? 100 OK

The address of VAR is on the stack.

@ replaces the address with its contents.

The value of memory location 6480 should

now be on top of the stack.

It is; this shows that VAR stores the

value 100.

This can be done on one line { ? } is the same as { @ . }

Listing 4: More string-manipulating words.

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

FIGFORTH1.1 MOVES IN-LINE STRING TO SSTACK

FORTH STRING STACK EXTENSION (") R DUP 2+ SWAP @ (

DUP 2+ R> + >R $@ ;

( IF COMPILING EMPLACE AN IN-LINE STRING TO

( BE MOVED TO STRING STACK AT EXECUTION TIME

( ELSE PUT ENCLOSED STRING ON STRING STACK

22 STATE @ IF COMPILE (

-1 ALLOT ELSE 0 C, WORD

HERE DUP 2 +

) 0 C, WORD DUP , ALLOT HERE C@ SWAP @ $

HERE Crj

1 ALLOT HERE !

ENDIF

IMMEDIATE

Listing 5: More string-manipulating words.

0 ( FORTH STRING STACK EXTENSION FIGFORTH1.1

1 0E + ORIGIN @ CONSTANT BS ( SYSTEM BACKSPACE CHARACTER = 8

2 7F CONSTANT PBS ( BYTE USED BY POLY 88 MONITOR AS BACKSPACE

3 : SINPUTPADDUP ( RTNS TEXT DELIM BY CR FROM KEYBRD TO $STK

4 BEGIN KEY DUP BS = ( IS IT A BACKSPACE? )

5 IF( BS ) >R 2DUP = R> SWAP ( AND AT START OF BUFFER?

6 IF DROP 0

7 ELSE DROP PBS EMIT 1 - 0

8 ENDIF

9 ELSE ( NOT BS ) DUP OD = ( IS IT A RETURN? )

10 IF DROP 20 EMIT 1

11 ELSE DUP EMIT OVER C! 1 + 0

12 ENDIF

13 ENDIF

14 UNTIL OVER - $@ ;

15 ;S

Listing 6: Defining a word to get the date from the keyboard. This word, GETDATE , prompts for and will accept only an input of exactly seven characters.

FORTH Statements

7 SVARIABLE TDATE : GETDATE BEGIN

$P! CR

" Input today's date (DDMMMYY): " $.

SINPUT

7 = UNTIL

Commentary

Begin definition of word GETDATE.

Start BEGIN...UNTIL loop.

Clear string stack.

Output message.

Accept input from keyboard.

Push length of string onto stack.

Compare to 7.

Loop to BEGIN if length of string * 7.

Listing 6 continued on page 162

160 February 1981 © BYTE Publications Inc

Circle 103 on inquiry card.

Thousands of SoftwareHows'Musers agree — SoftwareHows products set a new standard of excellence for solution-oriented software. Instant installation for your system, powerful "word processing-like" editing facilities and consistentoperating features make this SolutionWare" the only serious choice for your needs.

Why settle for a piece when you can have the whole pie?!

Payroll

Cost Accounting r

At last! An integrated system of business software ideal for you!

How often have you purchased software only to be disappointed by its features or frustrated by the inability of the different programs to work together? Are you tired of entering the same data into your Purchase Ordering System when a part is ordered, into jnventory when it arrives, Payables when it's invoiced and General Ledger when it's paid for? Can you easily link your Accounting Data Base with your word processing software to create personalized letters, reports, notices and announcements?* Does your Point of Sale, Order Entry software also save a keyed file which may later be Sorted for over 60 customer characteristics and used to generate personalized sales literature?

If you don't like your answers to these questions, your accounting software is costing you money!

The Data Base lntegration'"System from SoftwareHows'"does all this and much more! This newest software product offers the perfect blend of performance, price and flexibility. Every single transaction feeds your master records. This common data base approach organizes all your business information so that every module is fully interactive. The result of this vast and easy to use data base is unique. You'll be amazed at how much better you'll understand the operation and cash flow of your business! And better understanding meansbetter planning— and higher profits for you!

The Data Base Integration System is built around the basic four accounting tools: General Ledger provides those all important balance sheets and income statements, Accounts Receivable and Payable take care of invoice control in a jiffy, while Payroll with Cost Accounting does your payroll and provides cost effectiveness data. All packages fully interact and are self-checking. The amazing Order-Right'"order entry system and MicroDaSys Inventory, give you one of the most complete sales management and material requirements systems available. Output is processed with lightning speed and meticulous accuracy: invoices, shipping labels, charge slips and COD tags. Orders automatically interact with Inventory and Receivables. If your stock is too low, Inventory recommends the best source of supply and approximate prices to pay. Upon authorization, a purchase order is generated. The receiving department verifies receipt and the invoice is transferred to Accounts Payable.

The Data Base Integration Business System is $2500. And that's for all seven packages! Now there's a deal too good to pass up! It includes over 1500 pages of user documentation, and a supply of computer forms. With our unique DBI Installation Program, getting the complete package up and running on your system is a breeze. Best of all, complete CBASIC source code is included with every CBASIC package. Current disk formats include 8" softsectored, 5" hard- and soft-sectored.

Call or Write for the SolutionWare "" to meet your software needs — today!

Order-Right"

Accounts Payable

" Inventory

□ □

Ask your dealer why our

business software is the best!

A Complete 200 page Overview of all SoftwareHows SolutionWare is yours for just $75, refundable with purchase.

a division of MicroDaSys

PO Box 36275 Los Angeles, CA 90036 (213)731-0876 TWX310-321-2378

r

CXI **

'" S

*"{!

^ UJ

fvJ O

ro cd

3 ^

en O

0 >

01 -^

to H

co

3 m

o

ro3

O)

cd -n

o

jO

m?

^<

Q. O

w

> 2 m

o

>

m x

tj tj m to co

H m

s$

o o i m

> tj

3D H

o < m co

> >

N)

(1)

o

M

o

O

n

ID

it

M

CD

cji

•■*

C/3

H

*■

Tl

CD

n

71

C)

<n

CI

3

Tl

(D

O

K> Tl Tl _ CD CD CD

o tj3 3

03 q® m En SJ O o

C0Q.QO

-i CD "D "D

00 Q. CD CD

= CO 3 3

O CD _! to

co o — o

3 O 3 3 3 CO CD CO O

Tl

Tl

22221

3

CD

3

CD

01 £0 01 01 (/)

CD CD CD CD K)

_ _, «. „ CO

CD

CD

O O O O IS}

O

O

"" Tl 2 2 <-»

CD CD K? S? O

II CD

3 cd

II CD

3 ni

ABL

le 9' le 18 male male

CD

CD

£ «? Jo m

— O 3 CD

O 3 CO

—

O

3 CD

SL 5L

CD CD

o o OO

"D TJ CD CD

3 3

oo ^ £

— O ~

O 3

3 CO

CO

O 3 CO 3 CO CO

-* -j. rororo-^cococorororo

CO CO <£^uCOCD|k^(D(D^

8 8 8888888888

01 01

=! en O o. CD

? 5 5'

J>

<J0

.^

—L

o

CD

—i

</» tV!

CO

O

o

O

o

-1

o

w

►—'

D TJQOC0QOC0O

' c c 5' _

oi oj_co (/)

' CJl CD 3^

■ <s<5D

■ i < - :£

§ * <m

n° CO

1J 01 f~i —

<

CD

Q. Qi

co -»

T)

CD *

O

o •<

i

-> TJ

CD

en CD

o

8 o 9- o

CD

CD =

u

t 3

CD

CD

01 01 ^

£°°*

°? = 00

< m ;

> <

CD

oT

CT CD

o

>

</></></> </> v> v, 00

U UMUK] Mr CO to A A to * If.

g 8 8 8 8 8 co

0

5LO

03

O-o

0) -T

o

ro ST

Q.

CO Ol

0

cntoiw^ococo^cnui^cjto^o

« o a< o <

!? C G > G > ® TJ 13 5° TJ SO

~ ®

M W tO (O

+ + f +

so go t?~ go

h > a«>

TJ T| 3=* TJ

a 2

so O

H

o«i

^®

2^

so

o„

TJ

H ■• SO G~

■z

O TJ

>>

W c/l

^^

cn > >Z so «

-< C/l

I

13 O 13 Ol

GO SO

2

Q

GO

>

o o

GO

TJ « > SO I

Tl

n

KJ

m H

H

to

n

<-<

a

T)

H

m

1

i/i

1

<

>~

>

Tl

1

>

1

m

i->

Tl

m

1

H

1

O

+,«

<

•H

>

Tl

50

Z

^

U

H

r/i

X

>

O

to H

«

m

TJ« > X

woogg ^ s

GO 13

>"

h o, o w ^ £2

Bira2Z V Q H

a i

"~ i i

z

Q

GO H > O

• w

§•■

DC --a

2r cu

re y

o ^r

S. c

CT. en

O m

3 D

Tl 2 05

HS I" ■ *

o^

_ «• 3 en

BJ 3

i— &1 Bi 3

1-1 N«<

00 TJ

S E.

•-i re

O „

00 re

IT1 X

01 n

■3&

3 00

o aa ™ r

»-r\ 01

5'2

re tj JP-C it Si 2"re

o tre

K) n jt

jiia £

01 cu

Jnn t

^ "> °

O >-i ^

en <

3 3 n

Q . *-^ M

vi 0?' °

■i^ Ti g

H 0 oi

? *3 2. «;• Htj -IE.

2 to re

5- ra en

V ™ T

^* , . "I

2 »■ 5'

3 C. 00 re «3 en

O 00 o

»-r* en t

WtJ

re cj re

$ 3

3" _ 0i ST < 3 re

cxu

re

12:00

S <' O- 3

re tj re >a 3 CS

3 *< 00 2 0C 5 C W ^00 g 3 P 5 re

re s

D.

01 "■ 3

" en J| ex ""

a.,"

c 3 3 EJ

cr 01

ft S-sTK T

01 en

P-c 2

H<<;

3 fc »-r» re

s -■

01

1 J f*D

01

en

2 -1

en

(J- jr*

01 o ^3

01

n 3 01 n

S" S =" ° 01 ™ a. 3 ►iff.-3 01

-■ n-~ 01

301 ttj ;

2^3

c

-1

re

<f

re

a.

re

>2

re

a 0

< >-rt -T

1> IT ff

5 ™ 3

3.^

01 9-1.

§"° °

en

01

"■ l-U IV I-.

S !fi 3.

3 2 00 en

en re g. o

01 i?0" 3 ^

3 "0

3 01 T

(1 Si

2 5'S

re 00 ™ 01

re H 01 re

en t en

"" " 3 3 X

ff. _ ff.O0 7t IT

en

en 5' "•

ff 00 O 3. en

3 ->* tr

fm 1—

00

cr

re

a.

01

$

o Z °

CL 3

„ c

0 a «01 c.

< 0- o

re Q- 3

3

01

9-re v,

&- -■ -1 re re

O- en n

^ re

"• P en

O 01 IT

E^£ n n co

f*r cu

re <■ „ "1 < 3

S. S-e o^ 3

"-cr

«. 2 re ff O -j O n- en

ft) 3-^ fT> ^ CD 3 CO

2. ^r O g ^S'tJ ff.

^^ " ~°°

t 3 3 "* re C 3 en

2r3 Ei ° O re "•■ ff. C 2. 3- 3 en n 1 00

O ^ -1 < en'

S re 1 n 3 re

s--°

re e 01 3 3.

en " re c <>CL ^ <„, S- re g ff 3 3- 3 Q

<N re ft • Q. ^ . 3

00

n re 3 3

TJ C

;(X) H

ac

a SI

CO rr

3" ° a

3'crS. 00 re 1

ff cr g-<

00 3

»T^ O

01

n,3

re

^ 3 en

ca

■"§ I re cr

<

re^^

re jr*

re

C ffj en oT re :<

en

S" c

CS re < 2r

Htj O -1 3 O 1 1

*

a:

a

TJ

t->.

a

Ul

-3

-i

H

O

^*

Ul

ri

Ti

a

-i

a 5'

Tl O

IT

r,"

TO

sa.

pa

H

en

TO

3

I

> >

CO

^ 5

o 3

re re ►n

s»

AS 5

core 2

G

^>

H 50

1 to Q 1 d ""i

«o

1 H SO £? D H > >K

1 h r

t w —

CO n

^ ^ 2 _

re » c r-t s.5

„2. a

3- 3 re 00

01

01

01 TJ 3 re

a. 2

01

^2

*ft en

si

en tr) y 2. re —

cr t

en ...

t, 3

°TJ

S.S*

3' en 00 jj

V) 5'

.00

3 01

re re

3^ C re O

01

a s

O """^

mOS.

V H°"

. IS o

m? a.

01 O IT

rr "1 3

re a. 5;

re o

i-t re

00 „

. re

C 3

01 01 3 Q. Q-re

s3

o 0Q

H

O

>

00

m

eji

j_

n

<

u

>

50

j

Tl

rn

3

0.

0

0

n>

0.

-^

CO

3

3

iU

^r

3

0 3

H

tl

>

H

PI

en ^

; 3* en '—' re „

-v- 3

-.?»

m o Z ff- SI re

re „. re en ff

3- ™ 3

01 x s;

™ re re

01 G en

n 3 ff

IT IT 2

re re 3

1-1 Q-,5 en .00

TJ ff. ~ O

3 re Ei re "

a

3

3- re

re re 2

IT Tl S

S T

re

a.

en 3

nre re

m 5' 3

O 1

> 3 os

H 5- ft

• re 3

01

01

re

cr

en cjo

re

re 3

a.

re

Ti

3'

H

d

3 " re ff.

>

re re

H

t ?

0

3

en

m

3" O

re "t

< "

j?

Fl

ID

re CS

t is oth GETD the da

lare

1r>™

re

T

" H T

00

han E wi date

3

O

t >r re t

w — re

00 cl <

B.B-S

an*3 ? W n

1—1 ^ ^T*

T, Q- 5;

5 ff

^ re

re c:

-1 3

Ei w O

"i n O

— 3

— TJ

$ 3

re tire ff. 3 O _ 3 9" re -r „ 3

$ n

o t

XI o

C "1

O CL

re tj

en S

_ 01

re re

•=T

re cs Cu n

5T re >< cr o 01

re <" en

re 33. re ^r 3

cr

00 2

? H

Ei. re

re

0 c

"1 T

t re re en x '

Ff Cj re tn

o

g en

IT O

3-TJ re en

^J.

fft

11

00

z

Tl

u.

r,

H

01

en

0

3

01

3

n

O

cr

cr

re

re

?

en

(11

*-t

*<

3

0

00

T-,

en

00 re

01

ff

n

3

o

3 '00

TJ 01 01 H ri ■

3 °«

cr cr 2 re ST Cu

2. n ^•2 3

0 2.

rr Cfl

"> 5T

3 T, 01 a,

^s re

►n

Cu " re

01 3

1 3" 2. re 00 2

^r en

CUTJ

re "i

T» O

TJ 01 *f>

•"1 " ' '

o 3

TJ

re < x

2. re

ff. n

£

ff, re

3 T

re

a. o

01 3 ' cr Ti re

3 x "" 9"1 °

csis

-m re cT Z

en C

C H en ^

Cu t re O 3:

3

< re

< Cu

—1

re

cr re

< re

en

0

0

01

3

-1

re

cr

C

3

-1

01

3

ff 3

C/i CD

»-i^ cr _> en <

I' 3

3 01

►1 01

O n

O 3 00 00

T "I «1

^_5 "1 <->

5"° <

TJ 3 C TJ

re x

Cu t re t 1 o

5- Ff

re re

01 g **

en 01 '

3

01

3 Cu

We know the Atari 800.

The experts at ComputerLand would like you to meet the com puter that leads two lives. By day, the Atari 800 is a hard working business tool. By night, it's a stimulating educator and fascinating entertainer.

On the job, the Atari 800 is a management tool. It can help you plan and control by providing timely reports on accounts payable and receivable, inventory control, and a wide array of other business and financial management functions.

At home, it can teach more than 15 separate subjects, from Accounting and Algebra to U. S. History It's a video blackboard that teaches, asks questions, then tells you if you have the right answers, so you learn at your own pace. It can also turn your TV set into a playground for some of the most challenging and enjoyable computer games you've ever played. And help run your household—manage your budget, balance the checkbook,

^B sophist:

Let tis

keep tax records, analyze investments, even organize your recipe file.

The Atari 800 is the heart of a whole family of computer peripheral equipment and accessories including Atari's unique plug-in Memory Modules. So it can grow as your needs and interests grow It's fully programmable and comes equipped with the Atari 800 Basic Language Cartridge. But with all its sophistication, the Atari 800 is simple, even for people who have never used a computer before.

introduce

^^ Stop by ComputerLand and

^K^P^^^^f^f get a thorough introduction ^^m ^LJ^^ to the computer that leads

W ^^ ^^k# two lives. Wm It could enrich your own life.

ComputerLand

H Over 150 stores worldwide. For the stores near you, call (800) 227-1617 ext. 118. From California call (800) 772-3545 ext. 118. From Hawaii and Canada call collect (415) 930-0777 In Europe call Luxembourg 43-54-55.

Circle 104 on inquiry card.

BYTE February 1981

163

Articulate Automata:

An Overview of Voice Synthesis

Kalhryn Fons and Tim Gargagliano 1394 Rankin St Troy MI 48084

The time has arrived for computers to begin speaking for themselves! We discussed some basic techniques for using the TRS-80 Voice Synthesizer in the October 1979 BYTE ('The TRS-80 Speaks," page 113). Response from readers showed many were interested in a more detailed look at voice synthesis. The information presented here is concerned with the basic theory of voice synthesis and the basic procedures involved in constructing a vocabulary. The type of synthesis we focus on is electronic phoneme synthesis. A phoneme is a basic unit of sound from which speech can be constructed.

Voice-Synthesis Technology

During the past two decades, almost every aspect of computer technology has progressed through several generations of advancement. A relatively recent addition to this list is speech synthesis. The area of computer technology which would seem to gain most from speech synthesis is the man-to-machine interface. This is an area which remains in need of a great deal of development. Today, computers play a role in almost everyone's life, yet we rely on a group of specialists to control the computers. If computer technology is to continue to advance, there will be a strong need for the inexperienced user to communicate directly with the computer. It seems obvious that the man-to-machine interface will be one of the biggest challenges facing this industry in the 1980s.

Another problem confronting computer users is visual confusion and/or saturation. This can occur after watching a video monitor or scanning a printout for hours at a time. Part of this problem can be eliminated by including a nonvisual output channel in the computer system. The

About the Authors

The authors are both employed by the Votrax Division of Federal Screw Works in Michigan. Kathryn Fons is a speech scientist; Tim Gargagliano is a computer engineer. Both have done extensive research in language-processing systems and have worked on the Votrax text-tospeech algorithm. They have a special interest in voice synthesizers in relation to the needs of the handicapped and invite inquiries at the address shown above.

obvious choice is voice, since most people normally communicate verbally. In a number of situations, the serial nature of voice output is more desirable than parallel data from a printout or video screen.

A number of applications are already using voice synthesis. Among these are telephone order-entry systems, telephone access systems, reading machines and terminals for the blind, communicators for the verbally impaired, and computerized dispatching.

Physiology of Speech

The production of speech in the human vocal system begins with a source of acoustical excitation to drive the vocal tract. There are two kinds of excitation: periodic and random. The first type of excitation is a pulse train caused by the vocal folds blowing apart and collapsing under lung pressure (see figure 1 on page 166). The pulse train is rich in harmonic content due to its sharp wave shape. The second type of excitation is noise (frication) caused by air passing over the articulators (tongue, cheeks, lips, teeth, etc) with the vocal folds open.

Phonemes containing periodic excitation are called voiced phonemes (eg: the vowel I a I). Phonemes containing only frication are said to be unvoiced (eg: the consonant ///). It is also possible for a voiced phoneme to contain frication (eg: the consonant Izl).

The human vocal tract is formed from resonant cavities including the mouth and nasal cavities which respond to input excitation by filtering the input. At any given time, placement of the articulators determines the frequency response of the vocal tract. Generating speech from the input excitation involves sequentially varying the frequency response of the resonant cavities in the vocal tract. This is done by movement of the articulators. The vocal tract is a fairly complex time-variant filter network.

Speech is composed of several bands of frequencies called formants (see figure 2). Each formant varies in position, amplitude, and quality with respect to time. A static sound, such as a continuous vowel, is produced by moving the air through the vocal tract and over the articulators, which are appropriately positioned to create

164 February 1981 © BYTE Publications Inc

Circle 105 on inquiry card.

THIS COULD BE THE START OF SOMETHING SMALL.

At Micropolis, we make a big deal over our small deals, too.

Because we believe there should be a place in the marketplace for the small systems integrator who doesn't order thousands of units at a time. And we do everything we can to take the big headaches out of building small systems for vertical markets.

When you ask us for help, we don't just slap a brochure in your hand, give you a plant tour, and show you out the back door. We actually work with you to get your system to market.

The single fact is, nobody can help systems integrators with

a broader range of high capacity, high performance, high reliability 51/4" floppy and 8" rigid disk products than we can. We offer storage modules, enclosures, power supplies, S-100 & SBC-80 controllers, cables and connectors, interfaces, single & multiuser 8080/Z-80 operating systems & disk BASIC software, documentation and tech training. And we offer as much or as little as you need, from complete sub-systems at the start to OEM drive and controller manufacturing licenses as you grow.

When you deal with Micropolis, you avoid a lot of the expense,

inconvenience and delay of trying to solve your own packaging, interfacing and system software development.

For more information about our system integrator program, call Jim Molenda at extension 330. He'll be glad to tell you all about it.

Because we're Micropolis.

And we've got big ideas for small system integrators.

MICROPOLIS

In the US: 21329 Nordhoff Street. Chatsworth, CA 91311 • 213/709-3300 In Europe: Micropolis International (U.K.) 0734-860817 Telex 851847395

Circle 106 on inquiry card.

Kill Surges Like Lightning!

,"*' i ■*» •••*''<_

Permanent protection for small computers, communications, medical and other sensitive electronic equipment. Surge Sentry works in parallel with the power line to shunt destructive power surges in picoseconds! Triggers at 10% above the nominal peak voltage.

At $89.50, it's less than the cost of a service call. Easy to install for immediate protection. Several models to choose from to fit your specific application.

For details and a free brochure, call or write:

RKS ENTERPRISES, INC.

643 South 6th Street, San Jose, CA 95112 (408) 288-5565

Dealer inquiries invited.

pHK>Dqrq

business programs for your micro

Proforma Income Statement and Balance Sheet

Managers' Budgeting Program

Capital Investment Analysis

$ 35.00

Depreciation Method Comparison

Histogram Formed From Set of Numbers

$ 20.00

Simple Loan Analysis

$ 15.00

Lease/Buy Analysis

Make-Buy Decision Analysis

$ 15.00

Mortgage Analysis

$ 15.00

Sales Commission Report

$ 15.00

Sales Manager's Information System

In BASIC—Source Listings Licensing Only

Send for Our Catalog

i

«

oho oqrrq prooucti ODSpotpTnon

14600 Detroit Avenue • Lakewood, Ohio 44107 Call [216] 221-9000

I J

(la)

/ \

/l[\

y \

COLLAPSED

PRESSURE BUILDS

BLOWN APART

VOLUME OF AIR EMITTED

COLLAPSED

PRESSURE BUILDS

(lb)

AIR PRESSURE

Figure 1: Periodic excitation of the human vocal tract starts with the vocal .folds repeatedly opening and closing (la), regulating air flow from the lungs. This results in a pulse train of air (lb) which passes through the resonant cavities of the mouth and nasal passages.

AMPLITUDE

F0RMANT 1 CENTER FREQUENCY

F0RMANT 2 CENTER FREQUENCY

FREQUENCY

Figure 2: Speech is composed of several bands of frequencies known as formants. Shown is a generalized formant envelope for the first two formants.

that sound. During the production of a word, the articulators are constantly moving from one phoneme position to another. This sequencing of the articulator movements is one reason why each sound in the sequence influences every other sound around it. Note that the change in articulator positions does not occur in a singlestep fashion, but rather in a continuous movement from one target position toward another. The frequency response of the vocal tract is in flux between the target of the last phoneme and the current phoneme. The acoustical changes that occur during the transition are referred to as dynamic articulations. They are important to the production of intelligible speech—human or synthetic. Without dynamic articulation, speech becomes choppy and often unintelligible.

166 February 1981 © BYTE Publications Inc

Circle 107 on inquiry card.

Circle 108 on inquiry card.

Q«MC

THE DIFFERENCE BETWEEN TOYS AND TOOLS IN MICROCOMPUTERS AND COMPONENTS.

17 7/8 W x 11 3/8 H X 18 3/4 D

SI00 bus

IEEE Std. Z80 processor card

Shugart SA1004 Winchester disk (8.4

MB formatted)

Shugart 801R 8" Floppy disk drive for

file loading and backup

64KB Dynamic RAM

2 Serial and 3 Parallel Ports

CP/M 2.2 Operating System - Std.

Complete Documentation

OASIS Multiuser operating system

Optional

LIST PRICE $7,650

17 7/8 W x 11 3/8 H x 18 3/4 D

S100 bus

IEEE Std. Z80 processor card

2 Shugart 801R Disk Drives

(Approx. 1MB formatted)

64KB Dynamic RAM

2 Serial and 3 Parallel Ports

CP/M 2.2 Operating System - Std.

Complete Documentation

OASIS Multiuser operating system ■

optional

LIST PRICE $4,450

SYSTEM 80W

SYSTEM 80

NNC Z80 CPU Board

Totally IEEE SI00 Standard

2 Serial Ports

3 Parallel Ports Vectored interrupts Real time clock

2716 Zapple Monitor PROM I/O Cable for Serial Ports

LIST PRICE $495

IMIMC

ELECTRONICS

15631 Computer Lane, Huntington Beach, CA 92609

Ph. (714) 895-8000 TWX (910) 596-2360

Today one dollar buys % of a business phone call

Today one dollar buys

6% readers who actually see

your sales message.

As your selling dollar buys less and less, it pays more and more to advertise in McGraw-Hill magazines.

As prices keep going up and up, McGraw-Hill magazines help 10.8 million decision-makers keep costs down.

For example, Chemical Week told chemical processing managers and professionals how exports credits could lower their debt-servicing costs. And Engineering News-Record showed the construction industry how to cope with the destructive effects of the 1981 federal budget.

By helping 10.8 million readers solve their inflation problems, we help you solve yours.

Today, the price of reaching one potential customer in McGraw-Hill magazines is only 16s.1 This compares to a cost of $6.07 for sending a business letter,2 over $3.50 for a business phone call,3 and an in-person sales call which, believe it or not, now costs $137.02.4

In times like these, when everything costs more, you may be tempted to spend less on your advertising budget. But our Laboratory of Advertising Performance (LAP) Report #5262 demonstrates that "Industrial companies that maintained or increased their advertising expenditure during the 1974-75 recession enjoyed higher sales growth than those that cut advertising." Write 1221 Avenue of the Americas, New York, N.Y. 10020 for LAP Report #5262 today. And let us help you make your advertising more efficient, as the price of all other selling tools becomes more expensive.

'•ne reader-noted impression in the average McGraw-Hill publication. 2The Darlnell Institute of Business Research. 3"Telephone Marketing* by Murray Roman. P. 87, McGraw-Hill 1976. 4Laboratory of Advertising Performance Report #8013.5, McGraw-Hill Research.

McGraw-Hill Magazines

m

With inflation, we're an even better buy.

Photo 1: A selection of voice synthesizers. Top left: Votrax MLI multilingual synthesizer. Bottom left: phonetic keyboard for controlling a synthesizer without the use of a computer. Right top to bottom: Radio Shack TRS-80 Voice Synthesizer, Votrax VS6 synthesizer, Votrax VSK single-board voice synthesizer. Not shown: Votrax SC01 single-chip voice synthesizer.

Photo 2: An electronic analog of the human vocal tract using filters, oscillators, and noise-source modules. Control of these circuits requires an understanding of the static and dynamic parameters of human speech.

Photo 3: A spectrum analyzer display of a static phoneme. The X axis is frequency; the Y axis is amplitude.

The Electronic Equivalent of the Vocal Tract

An electronic analog of the human vocal tract can be constructed using filters, oscillators, and noise-source modules (see photo 2). Control of these modules is complicated, and requires measuring the static and dynamic parameters of human speech.

The study of speech parameters requires some complex instruments. Speech is most frequently considered in terms of frequency composition, rather than waveforms measured as a function of time. Therefore, analysis of speech is typically carried out in the frequency domain. This requires instruments that are able to measure and plot frequency, amplitude, and time in various relationships. A spectrum-analyzer scope can display a picture of amplitude versus frequency for an instant in time (see photo 3). This provides accurate measurement of energy distribution among the frequencies of a static sound.

Another type of spectrum analyzer used in the study of speech is a voiceprint machine. This device provides a picture of amplitude versus frequency versus time which is collapsed into two dimensions (see photo 4 on page 172). This type of printout allows us to study the dynamic characteristics of speech, such as phoneme duration and dynamic articulations. Notice how the frequencies continuously move during the transition from one phoneme to the next.

The area of computer technology

that stands to gain most from

speech synthesis is the

man-to-machine interface.

With these instruments, measurements can be made of the center frequencies of formants, their amplitudes, and their bandwidth. These measurements are the basis for designing the filter networks used in an electronic vocal tract. A model of a voice synthesizer in its simplest form is shown in figure 3. Depending on the desired speech quality, a varying number of parameters must be controlled. The number of bits stored for each parameter depends on the needed range and quantization tolerance of each parameter. To control this type of synthesizer, parametric data must be updated every 5 to 25 ms. The update frequency must be high enough to capture the parametric movements during phoneme transitions. While this synthesizer model can provide much flexibility, it does so at the expense of a high bit-rate/storage requirement and complex vocabulary generation.

The Votrax Phoneme Synthesizer

A phoneme synthesizer can be modeled by adding a parametric control generator and a dynamic-articulation control unit. A model for a Votrax phoneme synthesizer with several options is shown in figure 4 on page 174. Rather than have the user update all the parameters of a phoneme several times during its production, the synthesizer automatically does it using an internal algorithm. Because the Votrax phoneme synthesizer is implemented totally in hardware, there is no requirement for an external computer/memory to generate phonemes.

A high-quality phoneme synthesizer (with many internal parameters) is no more complex for the user to con

170 February 1981 © BYTE Publications Inc

64KMINI

64K TWIN MIWI + 10M 51A HD

(8SLOTS-100) SINGLE USER

(8SLOTS-10U) DRIVE EXPANSION

DUAL PROCESSOR

LINKED USERS

64K-1 & 2MB FLOP

/

B4K-10MB-1MB FLOP

CONVENTIONAL SINGLE USER SINGLE USER - HARD DISK SINGLE USER-LARGE DATA BASE

35MEG-17MEGTAPE

128K-2MB- FLOP

QBi

TWO USERMP/M®

256K-10MB- FLOP

2-4 USERMP/M®

35-70MEG-17MEGTAPE

2-8 USER MP/M®

5X64K-10MB-1MB FLOP

5X64K-35MEG-17MEGTAPE

DRIVELESS SLAVE NETWORK

w

MINI DRIVE SLAVE NETWORK

1BUSER NETWORK CP/NET®

with 8 Levels of Host Background Tasking

lVTP5in«J" Emulation Available on ALL Systems: circle no on inquiry card.

...j.TXCrt.niS, ^-^^^IBM3780, 2780, 3741, 2770 and SOLD ONL^

• Mnrp Add-Gw ^nIpQ^^^BM3^2\PllJ^$,^J^A THRU DEALERSHIPS

* IVlUrV J±lUL-\J¥l &llieb, ^"-^H)P-11, RSTS-E, TOPS MP*&C«NHAMMG.TM<*r^LReSEA^INC.

* Less Duplicate Inventory. ^\ <«* Deck 10 & 20

* Less Hassle from the Competition,

* More "Yes" Answers to your Customers

15392 Assembly Lane,

Huntinton Beach, CA 92649

Telephone: (714) 898-1492 TELEX:681-367 DELTMAR HTBH

Photo 4: A voiceprint of the message "hello readers." The X axis is time; the Y axis is frequency. Amplitude is displayed as a function of print density.

/rite pi | ^>

WRITE PN I ^>

PARAMETRIC

RAMETRIC I v.

DATA BUS I y

-A

FS- FRICATIVE EXCITATION SOURCE PS- PERIODIC EXCITATION SOURCE FN- FILTER NETWORK a- VARIABLE AMPLIFIER GAIN

Figure 3: A parametric speech synthesizer. The number of bits stored for each parameter depends on the needed range and the quantization tolerance of each parameter. In order to control this type of synthesizer, parametric data must be updated every 5 to 25 ms.

172 February 1981 © BYTE Publications Inc

ALL THESE FEATURES...

IN THIS SMALL SPACE...

AT THIS LOW PRICE!

Greater computer power. . . fewer separate components . . . larger capability . . . simpler to operate . ... modular maintenance . . .

These are the unique benefits of the Quasar Data QPD-100 Floppy Disk Computer. . . plus unsurpassed reliability.. .plus 12-month warranty on all PC boards.

Its highly reliable, industry-standard MFE drive is compact. Accepts both single AND double-sided disks.

Upgradeable from the Z-80T« microprocessor-based system to our Z8000® microprocessor-based system by simply plugging in extra PC cards. Hard disk and multi-user systems available.

As your requirements grow, your QDP-100 can grow to fit them.

The Quasar Data QDP-100H is a larger version with 6-megabyte capacity; includes one double-sided floppy and one 5V4 microwinchester hard disk.

Both the Quasar Data QDP-100 and QDP-100H are fully compatible with all standard terminals.

Phone or write for descriptive bulletin and specifications. And ask for a demonstration. Dealer inquiries invited.

QUASAR DATA'S QDP-100 COMPUTER SYSTEM.

4,695

18" wide 16%" deep 11" high

Complete systems available

"Z-BO and Z-28000

are trademarks ol Zilog Corporation

-CP/M andMP/M

are trademarks ot Digital Research Corp

10330 Brecksville Road, Brecksville (Cleveland), Ohio 44141

Phone: 216/526-0838 / 526-0839 Telex: 241596

Circle 111 on inquiry card.

BYTE February 1981 173

f

01

o

H <

at

LU Z UJ

o

-J o

ft:

Z o o

o

ft: 1UJ

s

< ft:

<c

0.

0

p

T 1

0 N A L

0£ LU

_l _J

o

\

z o o

z o

1<

o 1

<

i

« z

o 0

p

T I

0 N A L

PHONEME COMMAND WORDS

N

P A R A M E T E R S

•

• FILTER CONTROL PARAMETERS

•

PHONEME

SELECT <

• • • ' J

6 BITS

FN

(

X<

FS

«r>—►

«^_rf

psh

a2^>—•>

st

f

OPTIONAL

,,

PITCH /

*

•

2-3 BITS

AMPLITUDE

1

1 BIT

RATE 2 BITS

1 *

•S- FRICATIVE EXCITATION SOURCE

I *

3S- PERIODIC EXCITATION SOURCE FN- FILTER NETWORK a- VARIABLE AMPLIFIER GAIN

,

r

TIMER

DUR

ATION

r

PHONEME

*

REQUEST

Figure 4: A basic Votrax voice synthesizer. A phoneme command word is presented to the unit on the positive edge of the phonemerequest signal. The parametric control generator greatly reduces the synthesizer data consumption by calling out N parameters from only 6 bits. The dynamic-articulation controller generates continuous parametric transitions at phoneme boundaries.

trol than a minimal unit because both utilize the same phoneme call-out procedure. A command word is used to signal phoneme production. The command word for a phoneme includes phoneme-select data and optional pitch, rate, and amplitude data. Typically, there are sixty-four phonemes produced, each requiring a 6-bit command word.

There are areas where a person

must interact with a computer, but

where the use of a visual output

channel is inappropriate,

unavailable, or ineffective.

A simple digital controller or microcomputer is all that is needed for vocabulary retrieval. In the phoneme synthesizer we have modeled here, the duration of each phoneme is controlled by an internal timer. At the end of an interval, the timer output momentarily goes low, requesting the interface to send the next phoneme command word. This phoneme request signal can be used to generate an interrupt request to a microprocessor or clock a command word out of a FIFO (first-in/first-out) buffer, an interface, or ROM (read-only memory). See figure 5 on page 176.

Several types of Votrax synthesizers are available. A recent addition to this family is the SC01, the first singlechip phoneme synthesizer; it represents a significant breakthrough in speech-synthesis technology. Contained in a 22-pin dual-inline package, this low-power CMOS (complementary metal-oxide semiconductor) synthesizer can be easily used on a printed-circuit board. Latched parallel inputs permit direct connection to a microcomputer data bus. A master clock input on the SC01 permits a variety of voice effects and highly textured sound effects to be generated.

Phonetic Programming

There are a few specific speech rules that dictate how phonemes are sequenced for intelligible speech output. Pronunciation guidelines and symbols, established by the IPA (International Phonetic Association), are often used to identify the phonemes and the altered or adapted units of sound (called allophones). These are used because the standard alphabetic characters may have more than one sound associated with a single symbol. Using phonetic guidelines, phonemes and/or allophones are combined to form the symbol sequence that represents the spoken word in a language. The written symbology, however, does not always directly translate into the sounds available in a phoneme synthesizer. Thus, a sequence of the synthetic phonemes constructed from the phonetic guide

Text continued on page 180

174 Febraary 1981 © BYTE Publications Inc

Circle 112 on inquiry card.

Let Crystal Be Your Guide on the Road to Adventure

APPLE

PET

:V5TRS-80

If you are the owner of an Apple, Pet, Atari, orTRS-80 and also have a disk drive, we have some of the finest fantasy software in the world for you. For those systems with sound capability, our games have Crystalsonics — a newly developed concept in tone generation. For Apple and Atari there are some truely superlative hires graphics. In fact. Sands of Mars offers 3-D graphics and flight simulation landing. It includes over 186 full screen hires maps of Martian terrain.

We nowserveover 30 countries around the world. Dealership and distributor inquiries are welcome. Special rates are available on larger orders. We have 48 hours delivery to anywhere in the continental United States. We are also looking for experienced programmers and new game software. Our royalty terms are extremely generous. If you have what you consider to be a quality product that you would like to have markete^please give us a call. If you would like to be a member of the Crystal User's Club and be eligible to receive free user contributed software, please submit a program of any type and a $10.00 membership fee. In return you will receive a Crystal Membership Card, a copy of The House of Usher, and a year's subscription to Crystal Vision.

HOUSE OF USHER — Wander through a haunted house. Rooms and LAS AR WARS — Crystalsonics - hires graphics - protect the planet

scenery in 15 color lo-res graphics. We offer a $100.00 prize to the first earth from a full scale alien invasion. Over three types of invading craft

person to solve the mystery. Over 200 monsters, objects and perils. and hundreds of approach simulations. The games speaks for itself.

$24.95 $29.95

GALACTIC QUEST — Crystalsonics - hires graphics -the ultimate WORLD WAR III — Crystalsonics - hires graphics - for you war game

space adventure. Vegan warships attack and fire in real time Simula- freaks, this is it! Iran and Irag - nuclear missiles - hires J scene bat

tion. Land on and trade with over 64 star systems in 3 galaxies. Allow tlefield - demolition squads - tanks - strategy. Custom designed for two

6-12 hours for play. $29.95 arm chair generals. Save the world from nuclear holocaust! $29.95

o

SUMER — Travel back through time to ancient Sumeria in the middle BENEATH THE PYRAMID — Crystalsonics - hires graphics - brand

east. You are given 10 years as king to restore this kingdom to prosper- new! Explore the pyramids and miles of winding secret tunnels beneath

ity. Plant, war, consult the astrologers -very hard to beat! $19.95 them. Enter at the Sphinx and find the hidden treasure chamber. All in

° „ hires with very aggressive monsters and many many perils. To win you

must find the golden cat and your way out!!! $29.95

LITTLE CRYSTAL — Especially designed anthology for children from ages 5 to 80. Includes Mr. Music which turns your Apple into an organ of sorts, gunk where two weird monsters shoot it out and many other educational as well as entertaining programs for children. True unique addition for kids who always feel left out of Dad or Mom's computerizing. $39.95

SANDS OF MARS — What we at Crystal believe to be the finest adventure game available to date. In addition to hires graphics and super tone routines where the user's system will support it, this game provides landing simulation, animation, and revolutionary 3-D graphics. It is the ultimate in space adventure and may take several weeks or months to play. It is the Oydessy of the Starship Herman on its maiden flight to Mars. The initial liftoff is animated and paddle controlled. The flight through space is in Hires 3-D Graphics with many animated scenarias. You must land your starship on Mars. It will lack enough fuel and supplies for a return voyage. You must lead your party through hundreds of Hires maps of Martian terrain and subterrainian passages. You then will secure adequate resources for take off, navigate your ship back to earth and attempt a successful touchdown. There is a mystery buried in the ancient city of Lemuria beneath the sands of Mars. We offer a $ 100.00 prize to the first space gamer to discover it. Good luck! $39.95

For more information you may write or call: Crystal Computer, 12215 Murphy Avenue, San Martin, California 95046

(408) 683-0696

(5a)

L— NEW PHONEME

■ NEW PHONEME

(5b)

DATA WRITE

V

DATA DATA

IN F|F0 OUT

SHIFT IN

SHIFT OUT

PHONEME COMMAND

PHONEME SYNTHESIZER

PHONEME REQUEST

(5c)

OUTPUT PORT

COMPUTER DATA BUS

A

LATCH

PHONEME

WRITEl •*"

IRQ'

Lt

Q CLR D Q CK

FLIP-FLOP

PHONEME COMMAND

PHONEME SYNTHESIZER

PHONEME REQUEST

Figure 5: Interface characteristics. A new phoneme is sent on the positive edge of the phoneme-request signal (5a). A FIFO (first-in/first-out) shift register (5b) provides an elastic buffer by shifting data in at a rate independent from the data being shifted out. Phoneme-request (5c) sets a flip-flop which generates an interrupt request (IRQ) to the microcomputer. When the computer writes the next phoneme command into the latch, the flipflop is reset.

Programming Phoneme Voice Synthesizers

There are a number of steps involved in programming a voice synthesizer. Initially, you will probably have to frequently refer to table 1, which lists symbols and example words which represent sounds:

•Select the words to be programmed.

• Speak the words out loud.

• Select the appropriate phonetic symbols to represent the sounds in the words. The number of phonetic symbols you use should equal the number of sounds counted when the words are spoken.

• Enter the phoneme sequence into the synthesizer and listen to the speech output. Check the synthesizer's pronunciation for the appropriate duration of each syllable and rhythm of each word. The accent (or stress) placed on each word or syllable will help define the duration parameter.

• Select the longer-duration vowel phoneme for the accented syllable and the shorter-duration vowel phoneme for the unaccented syllable. Reenter the program and listen to it again.

• Adjust the program as many times as needed to achieve the desired pronunciation. This can be done by selecting different vowel-phoneme durations for the stressed vowel so that the durational relationship between the syllables sounds correct (see table 3). You can also adjust the sound by inserting a transition allophone between main vowels and consonants to achieve smooth pronunciation (see tables 2 and 3).

A few examples are:

Word Initial Program

move M-U-V family F-AE-M-L-E1

Refined Program

M-U1-U1-V F-AE1-EH3-M-L-Y

harvest H-AH-R-V-I3-S-T H-AH1-UH3-R-V-13-S-T

Phonetic Symbols

Key Words

Phonetic Symbo

s

Key Words

Votrax

IPA

Votrax

IPA

B

b

bat - rub

NG

rj

ring - drink • single

D

d

dad - raid

G

9

get - log

R

r

race - hard - hair

P

P

pack - flap - happy

L

I

tow - /ate - call

T

I

rip - par - asked

W

w

wake ■ always - when - quit

K

k

frill - kick

Y

J

yard • berry

DT

t

buffer

A.A1.A2

e, el,e2(

ei)

tame - pa/I - make

Z

z

zap - haze - pans

E,E1

i, il

beef - be - even

ZH

I

pleasure - azure

1,11,12,13

i.il, i2,

i3

p/t - /n - sw/m

V

V

van - pave

0,01,02

o, ol, o2

for - torn - bold

THV

b

the - smooth - mother

U,U1

u, ul

move - school - June

J

^

job - jazz - age

AE.AE1

ae, ae1

dad - pla/d

S

s

soup - ask - pass •

;ity

AH,AH1,AH2

a, a1, a2

top - father

SH

/

sheep - fish - acfior

AW,AW1,AW2

o, 01, 02

call - paw

F

f

fa/ce - cuff - phone

laugh

EH,EH1,EH3,EH3

e, el, e2,

ii

ready - leg - said

TH

e

thing - math

ER

&

third - heard • chum - over

CH

t/

cheese ■ march - match

UH,UH1,UH2,UH3

a, aI, a2,

3

cop - random • around - under

H

h

hoop - have

00,001 IU

u, ul lju)

took - put - good - could you - music

M

m

mat - dim

AY

tei)

jade - made - cla/m

N

n

no - son

Y1

(Jul

you - music

Table 1:

Phoneme

conversion

table. Shown are the

Votrax and IPA (Internationa

/ Phonetic

Alphabet) phonetic symbols and

example

words that show the

pronunciation of each

sound.

176 February 1981 © BYTE Publications Inc

Circle 113 on inquiry card.

THE FRONT RUNNER

ALPHACOM SPRINTER 40

40 COLUMN HIGH SPEED MATRIX PRINTER/PLOTTER

GRAPHIC 280 XN DOT MATRIX. □ PRINT SPEED TO 240 LINES PER MINUTE. USES OLIVETTI PU 1840 THERMAL PRINTER. □ ROLL AND FAN FOLD PAPER FEED.

SPRINTER 40 is a highly reliable printer/plotter providing long life-expectancy

and low power consumption. It may be connected with TRS80, Apple II, Atari- 800,

Commodore Pet, and all other computers, using standard interface.

ALPHACOM DISTRIBUTORS:

See us at CES, booth 2853.

Pen-Tech Associates, Inc. Microlex International I/O Sales Inc. Sylex Corporation Kitchen & Kutchin Inc.

1202 Eastchester Dr. 215 Park Ave. South 2551 Casey Ave. 4332 E. La Palma Ave. 428 Marrett Rd.

High Point, N.C 27260 New York, N.Y. 10003 Mtn. View, CA 94043 Anaheim, CA 92807 Lexington, MA 02173

(919)883-9125 (212)677-8400 Tel. (415) 968-1080 Tel. (714) 528-4480 Tel. (617) 862-8230

Front Vowels

Medial Vowels

Back Vowels

Mouth

Base Vowels

E

1

A

EH AE

ER UH

U

00

0

AW

AH

Closed

t

Open

Vowel

Allophones

(durational)

E1

11,12,13

A1.A2

EH1,EH2,EH3

AE1

UH1,UH2,UH3

U1

001

01,02

AW1.AW2

AH1.AH2

Closed

f

Open

Vowel

Allophones

(sound)

Y1 (short, constricted E1) AY (short, relaxed E1)

IU (between the 001 and U1)

Closed

Table 2: Vowel phonemes are categorized here according to their place of production within the human vocal tract. Durational vowel allophones have a number following their symbol which indicates their durational relationship to the base vowel. (The suffix 1 indicates the longest duration; 3 indicates the shortest duration.) The Votrax phonetic symbols are used here.

Consonants

Voiced

B,D,G

Z,ZH,V,THV,J

M.N.NG

R.L.W.Y

Voiceless

P,T,K,DT S,SH,F,TH,CH,H

Group Name

Stop Plosives Fricatives/Affricates Nasals Semivowels/Glides

Table 3: Consonant phonemes are listed here according to their voicing quality and grouped according to the manner in which they are produced. Note that all vowels are classified as voiced phonemes.

Phoneme

Phoneme

Sequence

Usage

Sequence

Usage

D-J

"j""-like sounds.

S

Completes the phonetic sequence of a

Example: Judge = D-J-UH3-UH1-D-J

word being pluralized only when the root word ends in a voiceless sound other than

T-CH

"ch"-like sounds.

S or SH.

Example: Church = T-CH-ER-R-T-CH

Examples: plants = P-L-AE1-EH3-N-T-S shops = SH-AH1-UH3-P-S

PAO

A short pause between words for rhythm. Example: Copy this list = K-AH1-UH3-P

laughs = L-AE1-EH3-F-S

Y-PA0-THV-I3-I2-S-L-I1-S-T

D

Completes the phonetic sequence of

Also used to separate stop-plosive sounds

a word with a past-tense suffix only

like "k"and "t" when they occur in se

when the root word ends in a voiced

quence.Example: Correct = K-02-R-EH2

sound or a T.

K-PAO-T

Examples: smiled = S-M-AH1-Y-UH3-L-D scored = S-K-01-02-R-D

PA1

The first and last phoneme in the completed sequence, used for maintaining the

wanted = W-AH1-UH3-N-T-I3-D

articulation of the first and last sound in

T

Completes the phonetic sequence of a

the sequence. Example: The sequence is

word with a past-tense suffix only when

complete = PA1-THV-UH3-UH3-S-E1-K

the root word ends in a voiceless sound

W-EH1-N-T-S-PA0-I3-I3-Z-K-UH1-P-L-AY

other than T.

Y-T-PA1

Examples: typed = T-UH3-AH2-Y-P-T

matched = M-AE1-EH3-T-CH-T

Z

Completes the phonetic sequence of

washed = W-AW-SH-T

a word being pluralized. Used only when

missed = M-I3-I1-S-T

the root word ends in a voiced sound, an

S, or an SH. (See table 3 for a list of

voiced sounds.)

Examples: cans = K-AE1-AE1-N-Z

balls = B-AW-L-Z

goes = G-01-U1-Z

ashes = AE1-EH3-SH-I3-Z

buses = B-UH3-UH1-S-I3-Z

Table 4: Since a number of phonetic sequences consistently produce intelligible

speech, they can be classified as phonetic pattern

rules. The most

consistent patterns are shown here. Other phonetic

patterns are

more flexible, and many specific "sound effects"

can be created

through experimentation.

178 February 1981 © BYTE Publications Inc

SuperSoft's

Gallery of CP/M Mas^erwbrks

SUPER-M-LIST: A complete, easy to use mailing list program package. Allows for two names, two addresses, city, state, zip and a three digit code tield lor added flexibility. Super-M-List can sort on any field and produce mailing labels direct to printer or disk file for later printing or use by other programs. Super-M-List is the perfect companion to TFS. Handles 1981 Zip Codes! Requires: 48K CP/M Supplied with complete user manual: $75.00 manual alone: $10.00

TFS-Text Formatting System: An extremely powerful formatter. More than 50 commands. Supports all major features including: • left & right margin justification • user defined macros

■ dynamic insertion from disk file • underlining and backspace TFS lets you make multiple copies of any text. For example: Personalized form letters complete with name, address & other insertions from a disk file. Text is not limited to the size of RAM making TFS perfect for reports or any big job. Text is entered using CP/M standard editor or most any CP/M compatible editor. Requires: 24K CP/M

Supplied with extensive user manual: $85.00 manual alone: $20.00 Source to TFS in 8080 assembler (can be assembled using standard CP/M assembler) plus user manual: $250.00

TEXT PROCESSING

DIAGNOSTICS I: Easily the most comprehensive set of CP/M compatible

system check-out programs ever assembled.

Tests:

• Memory • CPU (8080/8085/Z80J • Terminal • Disk • Printer To our knowledge the CPU test is the first of its kind anywhere. Diagnostics I can help you find problems before they become serious. A good set of diagnostic routines are a must in any program library. Minimal requirements: 32K CP/M. Supplied with complete user manual: $75.00 Manual alone: $15.00

DIAGNOSTICS II: Includes all of Diagnostics I, plus:

• Every test is "submif'-able

• A complete Spinwriter/Diablo/Qume test has been added (Serial Interface only)

• Output may be logged to disk

• Expanded memory test

• Expanded terminal test Expanded disk test

Diagnostics II provides the next level in system maintenance.

Requires: 32K CP/M

Price: $100.00 Manual only: $15.00

SYSTEM MAINTENANCE

****** Antnt ,**■****** A^JP

'TINY' PASCAL II: We still call it 'Tiny- but it's bigger and better than ever! This is the famous Chung-Yuen 'Tiny' Pascal with more features added. Features include:

• recursive procedures/functions • integer arithmetic • CASE

• FOR (loop) • sequential disk I/O • 1 dimensional arrays

• IF...THEN...ELSE • WHILE • PEAK & POKE

• READ & WRITE • REPEAT...UNTIL • more

"Tiny" Pascal is fast. Programs execute up to ten times faster than similar BASIC programs. SOURCE TOO! We still distribute source, in 'Tiny' Pascal, on each discette sold. You can even recompile the compiler, add features or just gain insight into compiler construction.

Requires: 36K CP/M. Supplied with complete user manual and source on discette: $85.00. Manual alone: $10.00

STACKWORK'S FORTH: A full, extended Forth interpreter/compiler produces COMPACT, ROMABLE code. As fast as compiled FORTRAN, as easy to use as interactive BASIC. SELF COMPILING: Includes every line of source code necessary to recompile

itself. EXTENSIBLE: Add functions at will. Z80 or 8080 ASSEMBLER included. Single license, OEM licensing available. Please specify CPU type: Z80 or 8080 Supplied with extensive user manual and tutorial: $175.00 Documentation alone: $25.00

SSS FORTRAN: The SSS FORTRAN compiler is fast, efficient, and complete (full 1966 ANSI standard with extensions). The RATFOR compiler compiles into FORTRAN allowing the user to write structured code while retaining the benefits of FORTRAN. The FORTRAN supports many advanced features not found in less complete implementations, including: complex arithmetic, character variables, and functions. Complete sequencial and random disk I/O are supported. SSS FORTRAN will compile up to 600 lines per minute1 Recursive subroutines with static variables are supported. ROMable "COM files may be generated. SSS RATFOR allows the use of contemporary loop control and structured programming techniques. SSS RATFOR is similar to FORTRAN 77 in that it supports such things as:

• REPEAT...UNTIL • WHILE - IF..THEN...ELSE SSS RATFOR is supplied with source code in FORTRAN and RATFOR. System Requirements & Prices:

SSS FORTRAN requires a 32K CP/M system. SSS FORTRAN with RATFOR: $325.00 SS FORTRAN alone: $250.00

RATFOR alone: $100.00

(Sold only with valid SSS FORTRAN license)

VWWH

PROGRAMMING LANGUAGE

sj^^gg^gjB

UTILITIES I: A collection of programs that you will find useful and

maybe even necessary in your daily work (we did!).

Includes:

GREP: Searches files for a specified string

SORT: In core sort of variable length records

CMP: Compare two files for equality

PRINT: Formatted listings to printer

PG: Lists files to CRT a page at a time

. . . plus more . . . Requires: 24K CP/M Supplied with manual on discette: $60.00

UTILITIES II: Many new programs not available elsewhere. Includes these "file" utilities:

DIFF: Source comparitor

PR: Powerful multicolumn output formatter

CAT: Concatenate files

RPL: Substitute strings in files

. . . plus more . . . Requires: 24K CP/M $60.00 Supplied with manual on discette

UTILITIES f"

TERM: A complete intercommunications package for linking your computer to other computers. Link either to other CP/M computers or to large timesharing systems. TERM is comparable to other systems but costs less, delivers more and source is provided on discette! With TERM you can send and receive ASCII and Hex files (COM too, with included convertion program) with any other real time communication between users on separate systems as well as acting as timesharing terminal.

• Engage/disengage printer • error checking and auto retry

• terminal mode for timesharing between systems

• conversational mode • send files • receive files Requires: 32K CP/M

Supplied with user manual and 8080 source code: $150.00 Manual alone: $15.00

1 INTERCOMPUTER COMMUNICATIONS!

*

... j;"-.;'--' j. -'■>....' r':c ■' ■■" \Jf'

ANALI2A: An amazingly accurate

: I :

.-.-.

simulation of a session with a

'■.-/

psychiatrist. Better than the famous

:'\

"ELIZA" program. Enlightening as

.V.

well as fun. An excellent example of

■.-.'

:

Artificial Intelligence. Requires: 48K CP/M, CBASIC2

Cost: $35.00

■-

P

j ENTERTAINMENT \ / 3

£

^

■.:"-... ,;'-;: ' ... %&* -: ... '','.:'" Z >

/

'•)}

ZB000CROSSASSEMBLER:Supports: full ZB000 syntax, segmented and

unsegmented mode, full 32-bil

-.-.

V.

arithmetic, hex output, listing output.

: : :

*.v

"downloader"

SB

Requires: 56K CP/M $500.00 1 year maintenance $300.00

':-.■

■*Yi

manual alone $ 50.00

■*'■

$

■ . : <-' : -| Z8000too! I ™ ■• ft

*

ENCODE/DECODE: A complete software security system for CP/M. Encode/Decode is a sophisticated coding program package which transforms data stored on disk into coded text which is completely unrecognizable. Encode/Decode supports multiple security levels and passwords A user defined combination (One billion possible) is used to code and decode a file. Uses are unlimited. Below are a few examples:

• databases • payroll files ■ programs ■ tax records

Encode/Decode is available in two versions:

Encode/Decode I provides a level of security suitable for normal use Encode/Decode II provides enhanced security for the most demanding needs. Encode/Decode I: $50.00 Encode/Decode II: $100.00 manual alone: $1500

SOFTWARE SECURITY |

On line "Help" system provided with every program package.

SuperSoft

First in Software Technology circle m on inquiry card.

CP/M Formats: 8" soft sectored, 5" Northstar, 5" Micropolis Mod II, Vector MZ, Superbrain DD/QD

All Orders and General Information:

SUPERSOFT ASSOCIATES

P.O. BOX 1628

CHAMPAIGN, IL 61820

(217) 359-2112

Technical Hot Line: (217) 359-2691

(answered only when technician Is available)

CP/M REGISTERED TRADEMARK DIGITAL RESEARCH

Circle 115 on inquiry card.

the POWER

Of Your HP-85 or Commodore Pet/CBM With TNWs IEEE-488 Bus System Building Blocks...

TNWs RS-232SERIAL INTERFACES

Connect your PET/CBM to any RS-232 Serial Printer, Piotter, Terminal. Modem, or other device:

CRT

TNW-1000 TNW-2000 TNW-232D

ONECHANNEL OUTPUT ONLY

ONECHANNEL INPUTANDOUTPUT

TWO CHANNELS, INPUT & OUTPUT 12 RS-232 CONTROL SIGNALS

$129 $229 $369

TURN YOUR PET INTO ATERMINAL

Access Timesharing Systems and Bulletin Boards with TNWs Pterm Software and full service telephone modem:

TNW-103

AUTO ANSWER/AUTO DIAL USE WITH DAA

$389

Pterm also works with acoustical couplers and other modems interfaced to the PET with the TNW-2000 or TNW-232D. Electronic mail and TWX Terminal programs also available. All units are addressable IEEE-488 devices, complete with power supply cabinet, full documentation and one year warranty.

TNW CORPORATION

3351 Hancock St. • San Diego, CA., 92110 (714)225-1041

TWX910-335-1194

Visa/Mastercharge Welcome • Dealer inquiries invited

Not for sale in any bookstore! Not available at any price! The new Consumer Information Catalog!

It's the free booklet that lists over 200 helpful Federal publications; more than half, free. On topics like home repairs. Money management

fpflbS. Generai Services Administration 180 February 1981 © BYTE Publications Inc

Nutrition. Information that could help you to a better way of life.

To get your free copy, just write:

CONSUMER

INFORMATION

CENTER,

DEPT E

PUEBLO, COLORADO

81009

AE1-I3

AH1-UH3

Phoneme Sequence Usage

AE1-EH3 The vowel sequence, for words requiring

the AE sound, that creates smooth pronunciation transition from the vowel into the following consonant. Also used to create duration for the stressed syllable. Examples: admit = AE1-EH3-D-M-I1-I3-T dash = D-AE1-EH3-SH

The vowel sequence for words requiring the AE sound followed by NG or another nasal sound. Example: hanger = H-AE1-I3-NG-ER

The vowel sequence, for words requiring the AH sound, for smooth transition into other sounds. Examples: got = G-AH1-UH3-T

father = F-AH1-UH3-THV-ER

S-S Doubles the S phoneme when more dura

tion is desired, as at the end of a phrase or sentence. Examples: gas = G-AE1-EH3-S-S

witness = W-I1-I2-T-N-I3-S-S

D-J-J Doubles the fricative portion of the "J"

sound sequence for emphasis. Examples: Germany = D-J-J-ER-R-M-I3-N-Y large = L-AH1-UH3-R-D-J-J

Table 5: In voice synthesis, it is often desirable to lengthen or shorten a vowel or consonant sound at the end of a syllable, word, phrase, or sentence. Shown here are several of the most common "tricks" for creating such effects.

Text continued from page 174:

lines might produce an awkward, if not unintelligible, pronunciation of the word being translated. The pronunciation guidelines from any phonetic symbol system (IPA, Webster's Dictionary, Thorndike's Dictionary) can be used to establish a basic synthesized phoneme sequence, but listening is the final step used to determine the selections for a refined phoneme sequence (see textbox, "Programming Phoneme Voice Synthesizers," on page 176).

For the purposes of this article, all phonetic sequences are presented utilizing the Votrax Phonetic Symbol System. This system is used because it utilizes characters that are" found on a standard computer terminal, as well as those needed for translation.

Phonemes

The sixty-four synthetic phonemes produced by a Votrax speech synthesizer are used here as the base synthetic-phoneme reference. The phonetic symbols representing these sounds and example words are listed in table 1 on page 176. There are twenty-five different consonant sounds, thirty-six basic vowel and vowel-allophone sounds, and two pause phonemes. The sixtyfourth phoneme is called a zero-decode command phoneme. It emits no sound, but can be used as a short interruption. When you select the appropriate synthetic sounds and place them in a specific sequence, the speech synthesizer can produce any word in the English language (as well as many other languages).

Vocabulary Storage

Vocabulary storage requirements are dependent on the

HOT WINTER PRICES ON PERSONAL COMPUTERS AND COMPONENTS.

Look at this!

Ohio Scientific Superboard II

$299

• It's the first complete computer system on a board.

• Superboard II uses the ultra powerful 6502 Microprocessor

• 8K Microsoft BASIC-in-ROM

• 4K static RAM on board, expandable to 8K

• Full 53-key keyboard, with upper and lower case. Plus user expandability.

• Video interface and audio cassette interface.

The Ohio Scientific Superboard II at $299 — in today's economy — has got to be the best buy by far. It will entertain you with spectacular graphics made possible by its ultra high resolution graphics and super fast BASIC. It will help you in school or industry, as an ultra powerful scientific calculator. Advanced scientific functions and a built-in "immediate" mode allow you to solve complex problems without programming.

The Superboard II can be expanded economically, for business uses, or to remotely control your home appliances and security. Even communicate with other computers.

Read what's been written about Superboard II:

"We heartily recommend Superboard II for the beginner who wants to get into microcomputers with a minimum cost. A real computer with full expandability." —POPULAR ELECTRONICS, MARCH 1979

"The Superboard II is an excellent choice for the personal computer enthusiast on a budget."

-BYTE, MAY 1979

Look at these easy hardware prices:

610 Board For use with Superboard II and Challenger 1 P.

BK static RAM. Expandable to 24K or 32K system total.

Accepts up to two mini-floppy disk drives. Requires + 5V

@4.5 amps. S 298

Mini-Floppy Disk Drive Includes Ohio Scientific's PICO DOS

software and connector cable. Compatible with 610

expander board. Requires + 1 2V @1.5 amps and + 5V @

0.7 amps. [Power supply S. cabinet not included.] 299

630 Board Contact us for important details. 229

AC-3P 12" combination black and white TV/video monitor. 159

4KP 4K RAM chip set. 79

P8-005 5V 4.5 amp power supply for Superboard II. 35

P8-003 12V power supply for mini-floppies. 29

CS-600 Metal case for Superboard II, 610 and 630 board

and two power supplies. [While stock lasts.] 49

CS-900B Metal case for single floppy disk drive and power

supply. [While stock lasts.] 49

AC-12P Wireless remote control system. Includes control console, two lamp modules and two appliance modules, for use with 630 board. 175

AC-17P Home security system. Includes console, fire

detector, window protection devices and door unit for use

with 630 board. 249

C1P Sams C1P Service manual 8

C4P Sams C4P Service manual 16

C3 Sams Challenger III manual 40

Ohio Scientific and independent suppliers offer hundreds of programs for the Superboard II, in cassette and mini-floppy form.

Freight Policies All orders of$100ormoreare

shipped freight prepaid. Orders of less than SI 00 please add $4.00 to cover shipping costs. Ohio residents add 5.5% Sales Tax.

ri Hours: Call Monday thru Friday. B;00 AM to 5:00 PM E.O.T. TOLL FREE: 1-800-331-5805

Guaranteed Shipment

Cleveland Consumer Computers S. Components guarantees shipment of computer systems within 48 hours upon receipt of your order. Our failure to ship within 48 hours entitles you to 835 of software, FREE.

TO Order: Or to get our free catalog CALL 1-800-321-5805 TOLL FREE. Charge your

order to your VISA or MASTER CHARGE account. Ohio residents call: [216] 464-8047. Or write, including your check or money order, to the address listed below.

I

I I I I

I I I

I

CLEVELAND CONSUMER U| COMPUTERS & COMPONENTS

| P.O. Box 46627

i Cleveland, Ohio 44146

■ BB1BB1BH ■■■■■■■■■■■■■■■■■■■ BB1 ■"■■"■■"■ BB1BB1 ■ flhrlan Cnnmi Cleveland consumer p.o. Box4eg27

Wl UCI rill Ilia COMPUTERS B COMPONENTS Cleveland, Ohio 44146

□ Superboard II $299. □ 630 Board $299.

□ 610 Board $298. □ AC-3P 12" B/W Monitor $159.

□ Mini-Floppy Disk Drive $299. □ C1 P Sams Manual $8. [Attach separate sheet for other items.]

NAME

ADDRESS:

CITY:

PHONE:

. STATE:

.ZIP:

Payment by: VISA

Credit Card Account #_ Expires

MASTER CHARGE.

MONEY ORDER

Interbank #[Master Charge]

TOTAL CHARGED OR ENCLOSED $_

. [Ohio Residents add 5.5% Sales Tax)

Orders of less then $100. please add $4.00 to cover shipping costs.

All orders shipped insured UPS unless otherwise requested. FOB Cleveland, Ohio.

Circle 117 on inquiry card.

BYTE February 1981

181

FOR THE APPLE

Please send: IJ Complete System S495.00 □ User's Manual only S35.00 D Detailed information

Name _ Address _

City

State

Zip

applied analytics incorporated 5406 Roblee Dr., Upper Marlboro. MO 20870

Listing 1: An example assembly-language program designed to store a permanent vocabulary for voice synthesis in a read-only memory. The program generates a table of words which the user has entered and stores them sequentially in memory. It then produces a look-up table with entries that point to the corresponding word in the wordstorage table.

00004 00005 00006

00008

00010 1000 >

00011 1000 00200820>

00012 1004 0D201220>

00013 1008 17201B20>

00014 100C 20202420>

00015 1010 29202E20>

00016 1014 34203B2O

00018 00019

00022 00023 00024 00025

00027

00028 2000

00028 2004

00029 2008

00029 200C

00030 200B

00030 2011

00031 2012

00031 2016

00032 2017

00033 201B

00033 201F

00034 2020

00035 2024

00035 2028

00036 2029

00036 202B

00037 202E

00037 2032

00038 2034

00038 2038

00039 203B

00041 00042 00043 00045

00047 0000

00048 0039

00049 003B

00050 002A

00051 0002

00052 0004

00053 0005

00054 0033

00055 0035

00056 002F

00057 0006

00058 0009

00059 0023

00060 0028

00061 OOOB

00062 OOOC

00063 OOOB

00064 OOOE

00065 OOOF

00066 0010

00067 0012

00068 0013

00069 0014

00070 0015

00071 0038

00072 0016

00073 0026

00074 0019

00075 001A

00076 0030 00077

2000 5

39350B30

13333513

0212002A

OB

0B0C0F15

1A

04092313

OB

06120526

0C333506

14

0E281515

13143B38

10

143B3526

OD

19281515

1A2F

1639350C

192815

00

THIS DEMONSTRATES HOU AN ASSEMBLER CAN PACK A UORB TABLE ANB GENERATE THE APPROPRIATE UORB LOOK-UP TABLE

THIS IS THE LOOK-UP TABLE

ORG 1000H

UORB

ACCESS,BREAK

UORB

CLOSE.BISK

UORD

FREE.LEFT

WORD

NEU.STOP

UORD

TIME.USER

UORB

VALUE,XXX

THIS TABLE UILL CONTINUE FOR AS MANY ENTRIES AS DESIRED OR MEMORY ALLOUS

THIS IS THE UORD STORAGE TABLE, IT CAN BE PLACEB UHERE YOU DESIRE. UORDS APPEAR IN THE ABOVE ORDER INORDER TO USE THE START OP THE NEXT UORD AS THE STOP FLAG 01 THE CURRENT UORD

ORG 2000H ACCESS BYTE AE1,EH3.K.PAO.S.»EH1,EH3.S■

BREAK BYTE B . . R . , Al . A Y,K

CLOSE BYTE K,L.,01,Ul,Z.

DISK BYTE D,,I1,I3,S,,K

FREE BYTE F,R,,E1,Y LEFT BYTE L .,EH1,EH3,F»T

NEU BYTE N,IU,U1,U1 STOP BYTE S,,T,AH1,UH3,P.

TIME BYTE T,AH1,EH3,Y,M.

USER BYTE Yl,IU.U1.U1,Z.,ER

VALUE BYTE V»AE1,EH3.L.,Yl.IU.Ul

XXX

BYTE

NOTICE! THIS SCHEME DOESNT CARE HON MANY BYTES ARE ALLOCATED TO EACH UORD. THERE ARE MANY VARIATIONS ON THIS SCHEME. PARTIAL PHONEME EUUATES BELOU

Al

AE1

AH1

AY

B.

D.

El

EH1

EH3

ER

F

II

13

IU

K

L.

M.

N

01

P.

R.

S.

T

Ul

UH3

V

Y

Yl

Z.

PAO

0 57 59 42

EQU EQU EQU EQU EQU 2 EQU 4 EQU 5 EQU 51 EQU 53 EQU 47 EQU 6 EQU 9 EQU 35 EQU 40 EQU 11 EQU 12 EQU 13 EQU 14 EQU EQU EQU 18 EQU 19 EQU EQU EQU EQU EQU 38 EQU 25 EQU 26 EQU 48 END

15 16

>0 21

56 on

182 February 1981 © BYTE Publications Inc

32K Board Pictured Above

Why Not the Best?

From The Dynamic RAM Company.

2MHz

4MHz

16K—$249

$259

32K—$375

$395

48K—$500

$530

64K—$625

$665

We have now been shipping our 2MHz dynamic RAM boards for over two years. Hundreds of 4MHz boards have been going out every month since early 1979. Our reliability is proven in the thousands of systems which contain our board. Many qualityminded systems houses across the country and overseas are using our boards for their equipment.

Our prices still beat all. Despite rising 16K memory chip prices (at least from reputable suppliers), Central Data continues to give you the best buy in memory today. Nobody offers a board with a capacity of 64K, assembled, tested, and guaranteed for a full year at the price we do.

Circle 118 on inquiry card.

Deselect around PROMs. Our

boards have the important deselect feature which lets you overlap any fixed memory in your system with no interference.

Our features make the board easily used and expanded. You address our boards on 1 6K boundaries with mini-jumps (small shorting plugs that slide over wirewrap pins) near the top of the board for easy access. If you want to expand your board after you have purchased it, all that you need to do is add memory. We can supply you with expansion packages ($1 50-2MHz, $160-4MHz) which include eight RAMs that you can depend on as well as two mini-jumps for addressing. And of course, our board never generates wait states.

Low power consumption keeps your computer running cool and reliable. The total power consumption of our 1 6K board is typically less than 4 watts ( + 8V @ 300ma, +1 6V @ 1 50ma and

- 1 6V @ 20ma). Boards with additional memory typically increase power consumption only 1 watt per 16K!

Standard S-100 Interface. Our board is designed to interface with any standard S-100 CPU. All of the timing of the board is independent of the processor chip, and the board is set up for different processors by changing two plugs on the board.

Call or write us today. That will guarantee a fast response with more information on the board. Or make an order — you'll probably have the board in two weeks! If you're interested, also ask for a catalog on our Z8000 16-bit processor board designed for the MULTIBUS. All of these products are available to your local dealer, also.

Central Data Corporation, 713 Edgebrook Drive, PO Box 2530, Station A, Champaign, IL 61820. (217) 359-8010

Central Data

BYTE February 1981

183

Your vehicle for com

The Challenger 8P DF.

The general purpose microcomputer was first introduced as a computer for hobbyists and experimenters. However, as the industry has grown, microcomputers have become specialized for personal use or for small business use. There is virtually no computer for the serious experimenter with one important exception, the Ohio Scientific Challenger 8P.

The C8P is unique in that it incorporates the features of state-of-theart personal computers, with the memory and disk storage capacity of business computers, along with the "mainframe" bus architecture and open ended expansion capability of industrial control computers.

Personal Computer Features

The C8PDF's specs beat all personal computers hands down. It executes instructions two to three times faster, and displays more alphabetic characters on its screen than other

models. It has upper and lower case and graphics in 16 colors. The C8P's standard I/O capabilities are far more extensive than any other computer, with joystick and keypad interfaces, sound output, an 8-bit D/A converter, 16 parallel I/O lines, modem and printer interfaces, AC remote control and security monitor interfaces and a universal accessory port that accepts a prom blaster, 12-bit analog I/O module, solderless prototyping board and more.

Ohio Scientific offers a large library of personal applications programs, including exciting action games such as Invaders and Star Trek, sports simulations, games of logic

and educational games, personal applications such as biorhythms, calorie counter, home programs such as checking and savings account balancers and a home budgeter just to name a few. A new Plot BASIC makes elaborate animations easy, and music composition program allows you to play complex multi-part music through the computers DAC.

At the systems level the machine comes standard with OS-65D, an advanced disk operating system with Microsoft BASIC and an interactive Assembler Editor. Optional software includes UCSD PASCAL and FORTRAN and an Information Management System (OS-MDMS). Dozens of independent software suppliers now also offer personal programs for the C8P.

I

puter explorations.

Business Computer Features

The C8P DF utilizes dual 8" floppy disk drives which store up to eight times as much information as personal computer mini-floppies, and an available double-sided option expands capacity to 1.2 megabytes of on-line storage. The C8P DF is compatible with Ohio Scientif ic's business computer software, including OS-65U an advanced operating system, and an Information Management System (OS-DMS) with supplementary inventory, accounting, A/R-A/P, payroll, purchasing, estimation, educational grading and financial modeling packages. The system also supports word processing (WP-3) and a fully integrated small business accounting system (OS-AMCAP V1.6). The C8P DF's standard modem and printer ports accept high-speed matrix printers and word-processing printers directly.

Home Control and Industrial Control

The C8P DF has the most advanced home monitoring and control capabilities ever offered in a computer system. It incorporates a real time clock and a unique FOREGROUND/ BACKGROUND operating system which allows the computer to function with normal BASIC programs, at the same time it is monitoring external devices. The C8P DF comes standard with an AC remote control

interface, which

allows it to control a wide range of AC appliances and lights remotely, without wiring, and an interface for home security systems which monitors fire, intrusion, car theft, water levels and freezer temperature, all without messy wiring. In addition, the C8P DF can accept Ohio Scientific's Votrax voice I/O board and/or Ohio Scientific's new universal telephone interface (UTI). The telephone interface connects the computer to any telephone line. The computer system is able to answer calls, initiate calls and communicate via touch-tone signals, voice output or 300 baud modem signals. It can accept and decode touch-tone signals, 300 baud modem signals and record incoming voice messages. These features collectively give the C8P DF capabilities to monitor and control home functions with almost human-like capabilities.

For process control applications, a battery back up calendar clock with automatic computer restart capabilities is available. Ohio Scientific's unique accessory ports allow the connection of a nearly unlimited number of 48 line parallel I/O cards and 12-bit high speed instrumentation quality analog I/O modules to the computer by inexpensive 16-pin ribbon cables.

Exploring New Frontiers

Ohio Scientific's vocalizer software processes normal BASIC print statements with conventional spellings and speaks them clearly in real-time

on computers equipped with the UTI (CA-15B or CA-14A). This voice output capability, combined with the C8P's remote control, remote sensing, telephone interface capabilities and reasonable cost open up new frontiers for computer applications.

Documentation

The C8P DF is not a beginner's computer and doesn't come with beginner's documentation. However, Ohio Scientific does offer detailed documentation on the computer which is meaningful for experts, including a Howard Sams produced hardware service manual that includes detailed block diagrams, schematics, parts placement diagrams and parts lists. Ohio Scientific is now also offering fully documented Source Code in machine readable form for OS-65D, the Challenger 8P's operating system allowing experimenters and industrial users to customize the system to their specific applications.

What's Next?

Ohio Scientific is working on a speech recognizer to complement the UTI system, with a several hundred word vocabulary. The company is also developing an 8 megabyte low-cost, add-on hard disk for use in conjunction with natural language parsing to further advance the stateof-the-art in small computers. The modular bus architecture of the C8P assures system owners of being able to make use of these new developments as they become available just as the owner of a 1976 vintage Challenger can directly plug in voice output, the UTI and other current state-of-the-art OSI products.

The C8P DF with dual 8" floppies, BASIC and two operating systems costs about $3000, only slightly more than you would pay for a dual mini-floppy equipped personal computer with only a fraction of the capabilities of the C8R

For more information and the name of the dealer nearest you, call 1-800-321-6850 toll free.

1333 SOUTH CHILLICOTHE ROAD AURORA, OH 44202 • [216] 831 -5600

Circle 155 on inquiry card.

Listing 2: A driver program in BASIC which accesses the vocabulary as stored by the program shown in listing 1. The end of a word is detected by the starting address of the adjacent word in the table.

Photo 5: A communicator for the verbally impaired. The Phonic Mirror HandiVoice HC-110 is a battery-operated speech synthesizer controlled by a microprocessor. The user can select from its 500 word/phrase vocabulary by touching the keypad.

Photo 6: The Phonic Mirror HandiVoice HC-120 is an advanced version of the voice synthesizer shown in photo 5. It has a 1000 word/phrase vocabulary selected by entering a 3-digit numeric code. Paralyzed users can operate the unit through the use of a paddle switch and a scroll mode.

100

'

SF'EECH OUTPUT SUE:ROUTINE

IN

BASIC

110

PHONEMES ARE SELECTED FROM

THE WORD

120

POINTED TO BY WNZ

130

140

X

1000H + 2 » HN7.

:

' CALCULATE LOOK-UP ADDRESS

lr-io

V =

F'EEK(X) + 256 * FEEKIX+1)

;

' LOOK-UP WORD START

160

z

PEEK<X+2> + 256 » PEEKCX+3)

:

1 LOOK-UP NEXT WORD START

17 0

F 0 R

X = Y TO Z-l

:

' SET UP LOOP ITERATIONS

mo

OUT

SPEECH,PEEK(X) ! NEXTX

j

' OUTPUT A PHONEME

190

RETURN

:

' EXIT

Photo 7: Talking typewriters for use by the verbally impaired. The units, which use phonemes, have a virtually unlimited vocabulary.

number of words in the vocabulary and the number of bits in a phoneme-command word. For example, a vocabulary of 100 words using a 6- to 8-bit command word to represent each phoneme will require 600 bytes of storage. A 1000-word vocabulary will require 6000 bytes of storage. A 12-bit command word will require 900 to 1200 bytes for a 100-word vocabulary and 9000 to 12,000 bytes for a 1000-word vocabulary (depending on the packing techniques).

When using a phoneme synthesizer with a 6-bit command word and a high-level computer language that allows literal strings to be assigned to a variable, vocabulary storage can be embedded within the program statements by using ASCII strings. This is because a 6-bit command word has only sixty-four possible commands, where there are at least 64 printable ASCII characters. A word or phrase is assigned to a string variable immediately before being sent to a speech-output routine. This routine pulls characters out of the string variable one at a time and sends them to the synthesizer. This technique is suitable for small vocabulary requirements. With large vocabularies, there tends to be word duplication because the storage unit is a sentence or phrase.

A technique better suited for handling large word bases is the assignment of the phoneme string for a single word to a subscripted string variable. This avoids the word duplication experienced by the previous technique and saves memory (provided that the language stores character strings with no wasted space). To generate a sentence using this technique, a sequence of variable subscript numbers is passed to a routine which calls up the indicated variables. Phoneme strings are then removed from the variable and sent to the synthesizer.

For permanent vocabularies stored in ROM (read-only memory) or loaded into programmable memory from a disk file, a word-address look-up scheme works well. This is done by generating a table of words stored sequentially in a portion of the memory. You then produce a look-up table whose entries point to a word in the word-storage table. The number of the look-up-table entry corresponds to the number assigned to the word (eg: the fifth entry in the look-up table will point to the fifth word in the word table). These tables can be generated easily (see listing 1). Sentences are called out in the same fashion as the previous scheme.

The assembler scheme works well with any size phoneme-command word, since it does not care how many bits are used to represent a phoneme. However, the driver program must know whether to pull 1, 1 Vz, or 2 bytes per phoneme. Listing 2 shows a driver program in BASIC to access the vocabulary in listing 1. Note that the

186 February 1981 © BYTE Publications Inc

end of a word is detected by the starting address of the adjacent word in the table.

Applications

In the field of computer technology alone, there is tremendous potential for the use of speech output. Through voice synthesis, applications can expand into areas formerly closed. These are areas where a person must interact with a computer, but where visual output is inappropriate, unavailable, or ineffective.

Currently, a blind person who wishes to use a computer must rely on a sighted person to relay information from a video display or printer. To eliminate this dependency, a terminal for the blind can be built to incorporate voice synthesis. Several such terminals are beginning to appear on the market.

Another situation where speech output is desirable is a warehousing/dispatching system. It is not often costeffective to place terminals around a large warehouse to list pending tasks. A better method is speech output from a computer connected to a radio link, which dispatches a worker carrying a pocket receiver/transmitter. Similar systems are in use or being developed today.

Another area where computers are presently ineffective is in interfacing with the nonreading population. Such is the case when the users are preschool children or nonreading adults. They are the prime candidates for using CAI (computer-aided instruction) as a supplement to their education. Applications such as computerized testing and evaluation of children would invite advancements in the educational field if a speech-output channel was used.

Synthetic speech applications are not limited to merely the computer peripherals mentioned. When used with a small, dedicated microcomputer or digital controller, a stand-alone device can be produced. Such is the case with a reading machine for the blind.

A second type of stand-alone speech system is a communicator for the verbally impaired. A battery-operated microcomputer system and a speech synthesizer can provide a voice for individuals stricken with neurological or physical disorders which impair the human speech mechanism (see photos 5 and 6).

Other applications for voice synthesis are in the area of entertainment electronics. Talking card games, chess games, and video games are beginning to use voice synthesis. Many of these applications are made possible by LSI (large-scale integration) circuits such as the Votrax SC01 single-chip voice synthesizer.

The interface of man-to-machine will provide a challenge for the 1980s. Speech synthesis will play an important role in the future of computer technology.■

Editor's Note: One of the first voice-synthesis products for consumers was Texas Instruments Speak & Spell, which uses a ten-stage lattice filter to simulate the human vocal tract. In the fall of 1980, as part of the continuing trend toward integrating voice synthesis into everyday products, MB Electronics (a subsidiary of Milton-Bradley) introduced an electronic game called "Milton." The game is controlled by a Texas Instruments TMS-1000-series 4-bit microprocessor and utilizes a custom voice-synthesis integrated cii --•<( designed by MB engineers....SM

The time has come for computers to talk and listen

Introducing COGNIVOX series VIO, the affordable voice I/O peripherals

If you have a

PET - TRS-80 - APPLE II AIM 65 - SORCERER

or any Z-80 CPU based system with at least 16K of RAM, COGNIVOXwill add a whole new dimension to your computer.

Imagine being able to use your voice for entry of commands and data and then listen to the computer talk back to you1 This exciting possibility has now become a reality at a very affordable price.

COGNIVOX, series VIO, is a family of voice input and output peripherals especially designed for personal computers that are easy to use and have excellent software support. You need only plug in COGNIVOX, load one of the programs provided and you will be able to have a voiceencounterwith your computer!

COGNIVOX can be trained to recognize words or short phrases from a vocabulary of up to 32 entries of your choice, with an accuracy of up to 98%. The voice response vocabulary can also have up to 32 entries chosen by the user. COGNIVOX requires that your computer has at least 16K of RAM. If it has less memory or if you are only interested in recognition, ask us about our SR-100 series of voice input peripherals.

COGNIVOX comes complete with microphone, power supply, (as required), built-in amplifier/speaker and extensive user manual. What makes COGNIVOX truly unique, though, is the soltware that comes with it on cassette. Some of the programs included are: DIALOG, a programthat lets you conduct a dialog with your computer (or translate from one language to the other); VDUMP, a vocal memory dump that reads the memory contents out loud; VOTH, a voice operated talking board game and VOICETRAP, a voice operated video game.

Adding voice I/O to your own programs can be done very easily too. All that is needed to have your computer recognize a word or say a word is a single USR statement in BASIC. No machine language programming is necessary.

With all these features, you'd expect COGNIVOX to cost a small fortune (after all, even talking chess games sell for over S300), yet it only costs $149 (add S4.50 for shipping in the U.S.. 10% of order overseas. CA res, add 6% tax) This low price has been made possible by innovative hardware and a technological breakthrough in recognition algorithm design that uses powerful non-linear pattern matching techniques and adaptive learning.

COGNIVOX is simply the most fun, most exotic peripheral you can buy for your computer. Write or call (805) 685-1854 for more it, motion, giving us the make and model of your computer. Or better yet, order a COGNIVOX today and bring your computer to life.

VOICETEK

Dept B, P.O. Box 388 Goleta, CA 93116

Circle 119 on inquiry card.

February 1981 © BYTE Publications Inc 187

Circle 121 on inquiry card.

REMOTE I/O

■* ~*l*'WWPB'MBMi

Control AND monitor remote devices Real time clock/calendar included

• An AC carrier communications I/O interface for the APPLE II* computer. Output communications operate up to 256 BSR System X-10* control modules. Input communications come from the X-10 command console, and temperature and security input modules, soon to be available from Intelligent Control Systems, Inc.

• Software routines are provided to handle the AC I/O, to set, read , and display the real time clock , and a background schedule control program. 4 selectable interrupt rates allow machine language programs to run simultaneously with other programs.

• Real time clock provides sec, min, hour, date, day of week, mo, and year. Rechargable battery runs clock when APPLE is off.

• Trademarks-APPLE II: Apple Computer Inc . ,System X-10 :BSR Ltd . SEE YOUR APPLE DEALER FOR A DEMONSTRATION...$185 Sugg. retail

Intelligent Control Systems, Inc.

POBOX 14571«MPLS,MN 55414« (612)699-4342

MICROSTAT NOW AVAILABLE FOR CP/M*

MICROSTAT, the most powerful statistics package available for microcomputers, is completely file-oriented with a powerful Data Management Subsystem (OMS) that allows you to edit, delete, augment, sort, rank-order, lag and transform (11 transformations, including linear, exponential and log) existing data into new data. After a file is created with OMS, Microstat provides statistical analysis in the following general areas: Descriptive Statistics (mean, sample, and population S.D., variance, etc.). Frequency Distributions (grouped or individual). Hypothesis Testing (mean or proportion). Correlation and Regression Analysis (with support statistics). Non-parametric Tests (Kolmogorov-Smirnov, Wilcoxon, etc.). Probability Distributions (8 of them), Crosstabs and Chi-square, ANOVA (one and two way). Factorials, Combinations and Permutations, plus other unique and useful features,

MICROSTAT requires 48K, Microsoft Basic-80 with CPIM and is sent on a single-density 8" Disk. It is also available on 5" diskettes for North Star DOS and Basic (32K and two drives recommended), specify which when ordering. The price for Microstat is $250.00. The user's manual is $15.00 and includes sample data and printouts. We have other business and educational software, call or write:

ECOSOFT

[master charge]

P.O. Box 68602 Indianapolis, IN 46268 V (317)283-8883

CP/M is a registered trade mark of Digital Research.

Technical Forum

Nonlinearities in Illumination

Christopher Terry, 324 E 35th St, New York NY 10016

I certainly do not wish to be hastily critical of an excellently documented and very interesting project. However, my points may help constructors to carry their experiments with computer-controlled light dimmers a bit further and to avoid disappointment with the results.

The dimmer, as described in John Gibson's "A Computer-Controlled Light Dimmer" (January 1980 BYTE, page 56), will certainly fade a lamp from blackout to full brightness or vice versa. However, it is important to realize that a smooth, steady fade cannot be obtained by incrementing the delay count in equal steps throughout the fade time. Linear change of this kind is an analog of the steady motion of a dimmer slide, whose scale is normally calibrated from 0 to 10 in equal divisions. On the other hand, the response characteristics of the digital dimmer, of incandescent lamps, and of the eye itself, are all highly nonlinear.

Figure 1 shows the curve of light output (expressed as a percentage of maximum light output in lumens) versus voltage applied to a lamp (expressed as a percentage of the rated, normal operating voltage). Data for this curve was taken from the Sylvania GTE Lighting Handbook

180

1- 160

a.

t

o 14°

H

I

IS 120

_l

D

£ 100

<

a.

u- 80

- /

O

1

z 60

/

u

rr

w 40

r- ^r

20

1 I- 1 1

20 40 60 80

PERCENT OF RATED LAMP VOLTAGE

100

120

Figure 1: The nonlinear response of light output versus the voltage applied to an incandescent lamp. Although the curve is almost linear above the 60% illumination point, an incandescent bulb can require as much as 40% of rated voltage to illuminate at all. Note that driving lamps with higher-than-rated voltage will reduce life drastically.

188 February 19B1 © BYTE Publications Inc

Circle 122 on inquiry card.

One Stop Shopping.

New CPU Card Completes the Package.

Now Tarbell offers a Z-80 S-100 CPU/IO board that rounds out its product line. Along with the single or double density floppy interface, the 32K memory card and the S-100 bus in the cabinet, this new CPU board means that Tarbell now offers everything needed to build a system. Just add a CRT and printer, and you're in business. Tarbell is now your one-stop shopping source.

One of the outstanding features of this new CPU board is memory-management hardware that allows dynamic mapping of logical to 1 Megabyte of physical memory in 4K blocks. Moreover, the CPU board is especially

Service

designed to make it easier to implement multiuser operating systems, such as MP/M™ from Digital Research. It can run at 2 or 4Mhz, jumper selectable. It has two RS-232 Serial Ports (one for printer and one for CRT), with full handshaking capability.

One of its additional important features is a crystalcontrolled programmable timer, which can be used for time-of-day clock and multi-tasking operations. Programmable priority masked vectored interrupt hardware is another useful feature.

In addition to all the features of the new CPU card, the double density floppy interface has DMA which makes the multi-tasking operation quite efficient. Also, the 32K memory board is static, resulting in a reliable memory. The Tarbell System with all three cards can be expanded for more memory and thus provides the ultimate in flexiblity.

Now Tarbell has it all.

rSl&mfThe °neStop Sboppinq

950 Dovlen Place, Suite B Carson, CA 90746 (213) 538-4251

MP/M is a trademark of Digital Research.

Circle 123 on inquiry card.

BYTE February 1981 189

Technical Forum —^—^—^_^^_

and is valid for most incandescent lamps. The most linear part of the curve is above the 60% illumination point. The nonlinearity is even more apparent in figure 2, which shows a standard calibration curve for theatrical SCR (silicon-controlled rectifier) dimmers controlling 120 V lamps from a 120 V RMS (root mean square) supply. The percentage of light output is also shown on the voltage axis. Note that 70 V RMS must be applied before the brightness reaches 10 %, and that raising the voltage from 80 V to 109 V increases the brightness from 25 % to 75 %. Figure 3 shows the predicted RMS voltage applied to the load for trigger-delay angles from 0° to 179°, and also the percentage of light output corresponding to the applied voltage. The angle versus volts curve was derived from the formula given in the SCR Handbook for triacs and back-to-back SCRs. The formula is:

V

LOAD(RMS)

/27T

(V-fl + 0.5(sin 2a))05

constant illumination at 20% of the maximum brightness of the controlled lamp, the apparent brightness of the controlled lamp follows a Munsell curve somewhat similar to the Munsell curve relating the apparent loudness of a sound to its frequency and power.

Because of these effects, theatrical dimmers, which receive a linear control voltage from the slide potentiometer, contain internal curve-generating circuits that cause the dimmer output to follow either the linear light curve of figure 2, or more usually the square law curve. The manner in which these curves relate linear dimmer motion to apparent light output is shown in figure 4—it is evident that the square law curve provides the most linear relationship, at least for the theatrical stage.

The eye is most sensitive in the region from 25% to 85% of maximum light output. In this range, a sudden jump of 1 V produced by a delay count change is perceptible, and jumps of 1.5 V to 2 V are quite obnoxious dur

where a (the firing angle) is in radians (not degrees), and Ep is the peak value of the supply.

Evaluating this equation with a BASIC program gave excellent experimental results. Using a 46 /is clock to drive the counter, computed values agree quite closely with this curve. (The true time for 1° per pulse is 8333/180 = 46.294 /is, but the 46 /is clock is easily derived from a 1 MHz system clock and is only 1° off at 160°.)

The human eye's response, too, is very nonlinear. When the area lit by a controlled lamp is surrounded by

Marway has the AC Power' Controller For Your System.

You'll find the ideal solution to AC power distribution needs in Marway's proven family of power controllers, From home audio visual centers to a time shared maxicomputer system. Marway products will stop "glitches", surges and unwanted line noises.

MPD 110 Series of 3W rack mount AC power controllers

• 10 outlets—8 switched Option). 2 unswitched id

• n5 VAC and 230 VAC

• 15 amp capactly

• High performance EMI li

• Opuonal remole control

MPD115 Series of DEC

Compatible Controllers

• interchangeable win DEC model 861 and priced 40% less

• 12 oullets —8 switched 4 unswiiched Idireci)

■ 115 VAC and 230 VAC models

• Up lo 30 amp capacity

• High pertormance EMI litter

• Optional delayed output and

MPD 117 low-cost AC power distribution

• Minimum cosl • 10 amp capacity

• 8 outlets —6 switched 2un- -High energy EMI tiller

All Marway Power Controllers provide organized,noise-free power distribution of standard AC current to eliminate frequently experienced line transients and associated problems. They turn a single wall outlet into a controlled power source. Contact Marway today,

Marwiy can solva your power distribution problems and save you money

, mflRWHY PPODLCT5 INC *

2421 South Birch Street, Santa Ana, CA 92707 [71 4) 549-0623 190 February 3983 © BYTE Publications Inc Circle 124 Ofl inquiry Card.

i

120

-VRMS APPLIED TO LAMP I PERCENT LIGHT OUTPUT

90

60

50

30

BLACKOUT

2 3 4 5 6 7 8

CONTROL VOLTS (E:) OR DIMMER SETTING

10 MAX

Figure 2: Calibration curve for theatrical lamp dimmers. The control voltage is interpreted by the dimmer to produce a linearseeming response. Note that the voltage actually applied to the lamp is not linear, but is related to the response of the lamp to voltage and the response of the human eye to light.

,0. ft

Cj

0

,«..■■ k*k

%%% ANSI 'ee STANDARD

IDCTRAN IV

WITH

CATfCC

DCD CD/M

TOGETHER AT LAST

SSS FORTRAN & RATFOR are the critic's choice!

The SSS FORTRAN compiler is fast, efficient, and complete (full 1966 ANSI standard with extensions). The RATFOR compiler compiles into FORTRAN allowing the user to write structured code while retaining the benefits of FORTRAN. Together they form an incredible team!

SSS FORTRAN Specifics

SSS FORTRAN makes full FORTRAN IV available to microcomputers. SSS FORTRAN meets and exceeds the ANSI 1966 FORTRAN standard. The compiler supports many advanced features not found in less complete implementations, including: complex arithmetic, character variables, and functions. SSS FORTRAN will compile up to 600 lines per minute! Recursive subroutines with static variables are supported. ROMable ".COM" files may be generated.

FEATURES

Code generation: ROMable ".COM" files or intermediate code files (saves disk space). External routines may be called.

Data types: Byte, integer, real, double precision, complex, logical, charac

ter and varying length strings.

Operations: All standard operations plus string comparisons, assignments,

and XOR.

Constants: Hexadecimal, decimal, and character literals with features to

imbed control characters.

Statements: ANSI 1966 standard with multiple statement lines, state

ments may end with a ';'.

Controls: Map, List, and Symbol table output options.

I/O: Read, Write, Append, Rewind, Close, Delete, Rename, Search,

sequencial and Random I/O on disk files. Supports all CP/M devices. The User can add device handlers to use custom I/O devices.

Errors: Over 200 distinct compiler error messages, precision and

illegal instruction warnings during execution.

Interrupts: FORTRAN programs may be interrupted at any time: the stack

pointer is always preserved.

• • DC ATLEING • •

SSS RATFOR

RATFOR is a preprocessor that compiles to SSS FORTRAN. SSS RATFOR allows the use of contemporary loop control and structured programing techinques. SSS RATFOR is similar to FORTRAN 77 in that it supports such things as: REPEAT... UNTIL WHILE IF... THEN... ELSE

Begin End Brackets Macro Defines

SSS RATFOR is supplied with source code. The source code is distributed in both RATFOR and SSS FORTRAN. Not only does this prevent obsolescence, but allows the user to add enhancements as desired.

iTTTTTTTTTTl

System Requirements & Prices

SSS FORTRAN requires a 32k CP/M system. Z80 only. SSS FORTRAN with RATFOR: $325.00 SSS FORTRAN alone: $250.00

RATFOR alone: $100.00

(Sold only with valid SSS FORTRAN license)

CP/M Formats: 8" soft sectored. 5" Northstar. 5" Micropolis Mod II. Vector MZ, Superbrain DD/QD

All Orders and General Information:

SUPERSOFT ASSOCIATES

P.O. BOX 1628

CHAMPAIGN, IL 61820

(217)359-2112

Technical Hot Line: (217) 359-2691

(answered only when technician is available)

•CP/M REGISTERED TRADEMARK DIGITAL RESEARCH

SSS FORTRAN is the copyright of Small Systems Services. Urbana Illinois

SuperScft

First in Software Technology

BYTE February 1981

191

Technical Forum

' RMS

(LOAD) i % LIGHT

120

40 60 80 100 120 140

TRIGGER DELAY ANGLE (DEGREES)

Figure 3: Effect of trigger-delay angle on the RMS voltage applied to the load of a thyristor-type dimmer. Plotted along with the percent of light output expected from an incandescent lamp, this curve is valuable for computer-controlled dimmer applications. This curve is based on calculations made with a 46 us clock, which may be developed from a 1 MHz system clock.

ing a long fade (eg: 20 seconds or more). To obtain a smooth fade, it is necessary that the linear timing pulses are translated to delay counts that will generate the square law curve. Also, since sudden changes are inevitable with a digital dimmer, it is desirable that the magnitude of each incremental change is small, especially during a long fade. This implies increasing the number of steps so that smaller, more frequent voltage jumps wi)\ better approach the continuous change of an analog dimmer. So far, I have obtained the best results by using an 8-bit delay counter, which is not started until after a delay of 20° (920 fis); the range from 20° to 160° is then divided into 256 steps. The actual value loaded into the counter is obtained from a software table that converts linear increments to values that follow the square law.

I have some cautionary notes to add, based on my own experiments. Triacs are much more persnickety and difficult to control than a pair of back-to-back SCRs with a bridge to steer the trigger pulse. Unless great care is taken in the design of the dv/dt and di/dt damping networks, triacs generate a much larger amount of RFI (radio frequency interference), are more subject to "pulling," are liable to be unpredictable and have infuriating interaction between channels on the same AC power phase. I have some doubt as to whether the simple RC (resistor/capacitor) damping networks shown by John Gibson in his figure 9 will support multiple channels, all changing at different rates in different directions, without interaction. A damped inductive filter is recommended by General Elec

Combine accurate flight characteristics with the best in animation graphics and you'll have SubLOGIC's

T80-FS1 Flight Simulator

fortheTRS-80

SubLOGIC's T80-FS1 is the smooth, realistic simulator that gives you a real-time, 3-D, out-ot-the-cockpit view of flight.

Thanks to last animation and accurate representation of flight, the non-pilot can now learn basic flight control, including take-offs and landings! And experienced pilots will recognize how thoroughly they can explore the aircraft's characteristics.

Once you've acquired flight proficiency, you can engage in the exciting British Ace 3-D Aerial Battle Game included in the package. Destroy the enemy's fuel depot while evading enemy fighters.

Computer and aviation experts call the T80-FS1 a marvel of modern technology. You'll simply call it fantastic!

Special Features:

• 3 frame-per-second flicker free animation

• Maximum transfer keyboard input

• Constant feedback cassette loader

Hardware Requirements:

• Radio Shack TRS-80, Level 1 or 2

• 16K memory

• Nothing else!

$

Only

25

See your dealer or order direct. For direct order, include $1.25 and specify UPS or first class mail. Illinois residents add 5% sales tax. Visa and Mastercard accepted.

iOO^LOGIC

Distribution Corp. BoxV, Savoy, IL 61874 (217)359-8482

192 February 1981 © BYTE Publications Inc

Circle 126 on inquiry card.

How to develop a silver tongue, a golden touch and a mind like a steel trap.

Il you want to lead others, it's essential to see things they miss.. .to know how to communicate your broader vision... and to tell your insights with a conviction that's inspiring.

Business Week helps give you that silver-tongued readiness of expression that's so critical in leading other people. Simply by making you remarkably well informed about business.

Gain years of business wisdom with just an hour or two of reading each week!

Every issue of Business Week contains dozens of articles - most quite short- that analyze every happening of note in the business community.

What you've been missing...

Here are some typical articles from recent issues: The new Arab weapon Their growing banking system could soon give the Arabs control over the economies and politics of the West. Juries out? Critics claim some business suits are too complex for civil juries. A new ruling agrees. Computer bottleneck With software development lagging, the computer industry could lose much of its momentum. A lack of programmers doesn't help. Cleaning up the image Even when liability is not an issue, some companies are clearing waste sites just to avoid bad press. Exotic tax shelters From wind turbines to wood chips, new energy projects are enticing investors.

tive managers who saw their profits

dwindle to nothing. (Good lessons in how not to succeed.) You'll also read about executives

who turned their companies around

through innovation... diversification...

centralization... or other careful

strategies. Their talent for success will inspire

you to perfect your own golden touch...

Take the measure of the current business climate (and see what's in it for you).

Business Week analyzes all the quirks of the current economy... reveals the health secrets of corporate "cash cows"... points out new markets that are mushrooming all over the world...

With input like this fed you every week, don't

be surprised if your mind grows so sharp and quick that it closes like a steel trap around every new business opportunity!

Enroll as a subscriber now

Just fill out and return the coupon below or the card opposite. We'll start Business Week coming your way at the basic subscription rate of only 69(£ per copy instead of the $1.75 cover price.

If you're at all disappointed, you may write "cancel" on our bill and return it to us with no further obligation.

So act now.

:" 7ES, start my subscription coming!

Each week you'll discover who's merging with whom. What's selling where. Why prices are soaring or plunging in all sorts of places...

Who's delighting stockholders. Who's infuriating employees. Who are leaping to power (or losing their jobs) in companies, unions and governments all over the world.

Watch the dramas and traumas behind the profit and loss statements.

Each week you'll read about bright ideas that bombed - and unimagina

Send 29 issues of Business Week at the basic subscription rate of $19.95. This saves me $30.80 off the $1.75 cover price.

If I'm at all disappointed, I'll write "cancel" on your bill and return it to you with no further obligation.

□ Payment enclosed □ Bill me

Guarantee: If Business Week everfails 10 meet your needs, you may cancel at any time and receive a relund for any issues not yet mailed.

Company

Address to mail.

(this is my D home □ business address)

State/Zip

For faster service, call Toll-Free (800) 523-7601 In Pennsylvania call (800) 662-5180

BusinessWeek

Circulation Department

1221 Ave. of the Americas. 40th Floor New York, N.Y. 10020

0-N703-0 Byte

Circle 127 on inquiry card.

BYTE February 1981 193

Technical Forum,

100

LINEAR VOLTAGE

4 5 6

DIMMER SETTING

Figure 4: Theatrical dimmer setting versus apparent light output. Internal curve-generating circuitry of most theatrical dimmers follows either the linear light curve or the square law curve, as shown.

trie, and I have found this type more effective in reducing RFI and interaction between channels. (See figure 5.)

Also, triacs seem to be more vulnerable to spike overloads than SCRs. This becomes important when you realize that applying full voltage to a cold lamp filament, which has a very low resistance, causes an inrush current

THE PROBLEM-SOLVER. HP-85 ... PLUS HP SOFTWARE.

HP-85 Appl""*5"" Pa*-*

•BASIC Training Pac

•Basic Statistics and

•General Statistics Pac

Data Manipulation Pac

•Financial Decisions Pac

•Math Pac

•Linear Programming Pac

•Circuit Analysis Pac

•Regression Analysys Pac

•Games Pac

•Text Editing Pac

•Waveform Analysis Pac

•Visicalc Plus

HP Flexible Disc Drives • HP82900 Series HP9895A wr

DATA BASE MANAGER

HEWLETT PACKARD

FARNSWORTH COMPUTER CENTER

1891 N. FARNSWORTH AVE. (At the East-West Tollway) AURORA, IL. (312) 851-3888 Weekdays 10-8; Sat. 10-5

120 VAC

MT2

MT1

NEUTRAL Q>

Figure 5: A damped inductive filter for triac dimmers. By removing RFI with an effective filter arrangement, interaction between dimmers can be reduced. This is especially important when multiple channels are used to control lamps at differing rates and in different directions.

spike that may peak at three to six times the normal fullbrightness operating current of the lamp. While lowwattage lamps warm quickly, the thermal inertia of lamps rated at 200 W or more may allow the spike to be several milliseconds in duration and cause damage to the triac. Triacs are particularly vulnerable to such spikes, and I make it a rule never to load a triac to more than half its rated maximum current in applications where full voltage could be applied to a cold filament.

Theatrical dimmers reduce inrush problems by keeping filaments warm with a blackout voltage of 12.5 V RMS. You may find that this results in a perceptible filament glow. If you reduce the blackout voltage to 6 V, you will kill the glow while still keeping the filaments warm enough to avoid inrush problems.

Finally, I suggest that readers interested in precise light level control and color mixing should consult the following books:

• The SCR Manual, 4th Edition. General Electric Co, 1967 or later. This is the basic bible on proportional control and SCR/Triac circuit design.

• Sylvania GTE Lighting Handbook. Sylvania Co, any recent edition. This is a handy reference book on incandescent lamps, fixtures, and space lighting principles.

• CORTL1 (Computer Output of Real Time Lighting Information), The Mimi Garrard Dance Company, Soho Loft Theatre, 155 Wooster St, New York NY 10012, 1978. (The cost is $10.) This describes a complete lighting system using digital dimmers under the control of an 8080-based microcomputer: about fifty pages on how it came to be, over one hundred pages of detailed technical information, including detailed schematics and software listings in 8080 assembly language, and some operating information. It's very readable, and you get a tremendous amount of both solid information and speculation about future possibilities; likewise, it's an excellent source book for the money. The system works really well, too! I have seen it in action a number of times. ■

Technical Forum is a feature intended as an interactive dialog on the technology of personal computing. The subject matter is open-ended, and the intent is to foster discussion and communication among readers of BYTE. We ask that all correspondents supply their full names and addresses to be printed with their commentaries. We also ask that correspondents supply their telephone numbers, which will not be printed.

194 Febiuary 1981 © BYTE Publications Inc

Circle 128 on inquiry card.

♦«

^

IT TALKS

55

"FAST TALKER S-100

LOW DATA RATE S100 SPEECH BOARD

• UNLIMITED SPEECH POSSIBILITIES

• S100 INTERFACE

• USES TEXAS INSTRUMENT TMS 5200 V.S.P.

• SOFTWARE VOICE DATA ASSEMBLER

• 32 WORD VOCABULARY INCLUDED

• AUDIO AMP W/SPEAKER

• ASSEMBLED AND TESTED

NEW TECHNOLOGY SPEECH PROCESSOR ALLOWING UNLIMITED SPEECH POSSIBILITIES DELIVERY FROM STOCK

$329

TMS-5200 VOICE SYNTHESIS PROCESSOR Chip with Data Sheet $69.00

"CONTROL

TALKER II"

• 32 INPUT LINES (TTL)

• 32 10 AMP (50V) OUTPUT LINES

• Z80 BASED SYSTEM

• 8K PROM (NOT SUPPLIED)

• 1K RAM

• VOICE OUTPUT

• SINGLE BOARD

Excellent Controller for Automation Burgular Alarms, Phone Solicitation, Relay Control, Value Control and many other possible uses.

$550

POLYESTER

CAPACITORS + &

10% TOLERANCE 50V

Value 1+ 25+ 100 +

-001m) 13 .II 08

0012ml 13 ii .08

0015ml .13 .II 08

.0018ml ,13 .11 ,08

0022ml .13 .11 ,08

0027ml .13 .11 08

0033ml .13 .11 .08

,0039ml .13 .11 .08

.0047ml .13 .11 .08

-OOSBm! .13 .11 .08

0068ml .13 .11 08

.0082ml .13 .11 08

■Olml .13 ii ,08

012ml 13 .11 08

.015ml 13 .11 .08

.018ml .14 .12 .09

022ml .14 12 09

,027ml ,14 .12 09

033mf )4 .12 09

■039ml .is .13 io

047ml .is 13 ,io

1ml ,12ml

15ml 18ml ,22ml 27ml 33ml 39ml

SOCKETS

LOW-PROFILE SOLDER TIN

Pari* SBLT S14LT SI6LT SiBLT S20LT S22LT S24LT S28LT S40LT

1+ 25 + 100 +

LOW-PROFILE GOLD

1 + 25+ 100 +

Part*

S8LG 30 27 24

S14LG 34 31 27

SI6LG .39 .35 .31

SiBLG .45 .40 36

S20LG 50 45 40

S22LG 53 48 42

S24LG 59 53 47

S28LG 67 61 54

S40LG 99 .88 .75

WIRE-WRAP SOLDER TIN

Pari* S8WT S14WT

S16WT S18WT S20WT S22WT S24WT S28WT S40WT

1+ 25+ 100 +

WIRE-WRAP GOLD

Pari*

S8WG S14WG

S16WG S18WG S20WG S22WG S24WG S28WG S40WG

1+ 25+ 100 +

74LS TTL

Pari* Price

74LS00 74LS01

74LS02 .:

74LS03 .: 74LS04 74LS05 74LS08

74LS09 .: 74L510 74LS11 74LS12 74LS13

74LS14 .!

74LS15 :

74LS20 .:

74L521 .:

74LS22 .: 74LS26 74LS27

74LS28 .: 74LS30

74LS32 .; 74LS37

74LS3B .: 74LS40

74LS42 .1

74LS47 .!

74LS4B I,'

74LS51 .;

74LS54 .:

74LS55 .:

74LS73 ,<

74LS74 ,i

74LS75 .!

74LS76 .!

74LS83 .!

74LS85 1.J

74LS86 .'

74LS90 .1

74LS92 .1

74LS93 .i

74LS95 { 74LS107

74LS109 .'

74LS112 J

74LS113 .4

74LS114 A

74LS123 £

74LS124 .«

74LS125 .i 74LS126

74LS132 ,( 74LS136

74LS138 .i 74LS139

74LS145 1.;

74LS147 2..

74LS148 U 74LS151

74LS152 74LS153 74LS154 74LS157 74LS158 74LSI60 74LS161 74LS162 74LS163 74LS164 74LS165 74LS166 74LS170 74LS173 74LS174 74LS175 74LS1B1 74LS190 74LS191 74LS192 74LS193 74LS194 74LS195 74LS196 74LS197 74LS221 74LS240 74LS241 74LS242 74LS243 74LS244 74LS245 74LS251 74LS253 74LS255 74LS257 74LS258 74LS259 74LS260 74LS261 74LS268 74LS273 74LS283 74LS365 74LS366 74LS367 74LS36B 74LS373 74LS374 74LS375 74LS377 74LS386 74LS390 74LS393 81LS95 81LS96 81LS97 81LS98

CRYSTALS

(Part* Includai frequency In MHZ)

SV1.S432

SY2

SY2.4576

SY3579

SY4

SY5.068

SY6

SY6.144

SY8

SY10

SY12

SY14.318K

SY15

SY18

Price

5 75 575 5.75 5.75 5 75 4 50

i 50

%WT & YrWT CARBON FILM 5% RESISTORS

3 3K 3 6K 3 9K

5 6K

6 2K 6 8K

27K 30K 33K

I10K

) IM

120K

1.2M

130K

1 3M

150K

ISM

160K

1.6M

180K

1 8M

200K

2M

220K

2 2M

240K

24M

270K

2.7M

300K

3M

330K

33M

910

510K 560K 620K 680K 750K 820K

MINIMUM ORDER PER TYPE: 5 pes any qty 5 pack ® $.25

MINIMUM ORDER PER TYPE: 100 pes Price Per 100 Pk:

QTY 'AWT

ViWT

100 up

1.000 up 5.000 up 10.000 u

TRANSISTORS

2N2219A S .35

SYlf

132

DIODES Switching

2N2222A

.25

2N2905A

30

2N2907A

25

2N2369A

.25

2N3904

.20

2N3906

20

PN2222*

.19

PN2907A

.19

VOLTAGE

REGULATORS

Part*

Case

Price

78L05

T092

.45

78L12

T092

4 5

78L15

T092

45

79L05

T092

.65

79L12

T092

65

79L15

T092

.65

7805P

TO220

1.20

7812P

TO 220

1 20

7815P

TO220

1 20

790 5P

TO220

1.25

7912P

TO220

1 25

7915P

TO220

1.25

7805K

T03

1.50

7812K

T03

1 50

7815K

T03

1 50

7905K

T03

1.60

7912K

T03

1.60

7915K

T03

1.60

309H

T039

.95

309K

T03

1.25

317P

TO220

1.95

317K

T03

295

323K

T03

5.50

337P

TO 220

2 40

RAMS

ZENER DIODES

Vi WT Pari* Price

1N5231B .20

IN5239B .20

1NS242B .20

1N5245B 20

1N5248B .20

1N5250B .20

1N5252B 20

1N5255B 20

1 WT

1N4733A 30

1N4739A .30

1N4742A ,30

1N4744A 30

1N4746A 30

1N4747A .30

1N4749A 30

EPROMS

2708 S 7

2716 * 5V 12

TMS2716 14

2732 39

CERAMIC DISC CAPACITORS 50V

Value 1 + 25 + 100 -t

4.7pf 07 06 .04

10pf 07 .06 .04

22p1 ,07 06 04

33P' 07 ,06 04

39pl .07 .06 .04

47pf 07 06 .04

68pf 07 .06 .04

'00pf 07 06 .04

I50p1 .07 06 04

220pl .07 .06 04

270pl .07 ,06 i)4

330pf 07 06 .04

470pl .07 06 .04

OOlmf .07 .06 .04

,O022mf .07 06 .04

0033ml 07 06 .04

0O47mf 07 .06 .04

Olmf 07 .06 04

022mf io .08 .06

,033ml io 08 .06

,047ml ,ii .09 .07

SOLID DIPPED TANTALUM

CAPACITORS 20% Value Volts 1 + 25+100 +

1.5ml 2.2mf 3.3ml 4.7ml 4.7ml 6.Bml 10ml 10ml

RECTIFIERS (1A)

100 4

12/1 00 10/1.00 10/1 00 10/1 00

LINEAR

M = 8 PIN N = 14/16 PIN Pari* Price

LF3S5M 1 10

LF356M 1 10

LF357M 1 10

LM301AM 35

LM307M 35

LM308M LM3MM LM318M LM324N LM339N LM377N LM380N LM381N LM555M LM556N LM565N LM566M LM567M LM709N LM710N LM711N LM741M LM747N LM145BM

Part*

7406

7407

7416

7417

7423

7425

7445

7446

7460

7470

7480

7469

7494

7497

74100

74104

74105

74116

74121

74128

2 95 2 95 2 95

MICROPROCESSORS & SUPPORT

Parte Price

8216 8224 8226

5 95 325 5 95 3 25 3 95 3 25

8228 8238 8251 9255 8257 Z80A Z80A-CTC

5 50 5 50

7 50

8 95

.■

6502 6522

12 95 1395

5 95 7 50

6 95

4000 CMOS B SERIES ONLY

Pari* Price

4000 35

4007 4008 4009

4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030 4034 4035 4040 4041 4042 4043 4044 4046 4047 4048 4049 4050 4051 4052 4053 4060 4066 4068 4069 4070

4075 4076 4077 4078 4081 4082 4093 4503

MIN ORDER: $10.00 SHIPPING: ADD $2. GA RESIDENTS ADD 3% SALES TAX

00

MASTERCARD AND VISA WELCOME

MAILORDERSSOUTHERN SEMICONDUCTORS INC.

BOX 986

LAWRENCEVILLE. GA. 30246 PHONE ORDERS:

OEM AND INSTITUTIONAL INQUIRIES INVITED (404) 963-3699

Circle 129 on inquiry card.

BYTE Febmary 1981 195

Kmim)p>

you're always a winner!

SUPER NOVA

Big Five Software

C/S-80 $14.95

GALAXY INVASION

Bio Flv« So (twin

C/S-80 $14.95

HELLFIRE WARRIOR

Aulomitld Simulation!

O/S-80 $29.95

D/Apple $29.95

C/S-80 $24.95

STARFLEET ORION

Automated Slmuliilom

C/S-80 $19.95

C/ApplB $19.95

C/Pet $17.95

O/S-80 $24.95

D/Appls $24.95

RESCUE AT RIGEL

Automitid Slmulltlom

D/S-80 $24.95

O/Appla $24.95

C/S-80 $19.95

C/Apple $19.95

C/Pet $19.95

VISICALC

Hidlo Stuck

O/S-80 $95.00

3 0 GRAPHIC

Sibnii Computing

C/Atarl $29.95

HI-RES MYSTERY HOUSE

On Llm Syolomi

D/Apple $32.95

HI-RES WIZARDS PRINCESS

On Llm Syltlmi

O/Apple $24.95

3 MILE ISLAND

Mull So twin

D/Appla $39.95

BEST OF MUSE

Mull Soltwirl

D/Appla $39.95

GLOBAL WAR

Mun Sottwiti

C/Apple $17.95

O/Appla $24.95

PINBALL

Acorn Soltwirl

C/S-80 $14

D/S-80 $20

DUEL-N-DROIDS

Acorn Software

O/S-80 S20.

C/S-80 $14

PIGSKIN

Acorn Sattwire

C/S-80 S9.S

SUPER SCRIPT

Acorn Soflwin

D/S-80 $29.

MIDWAY CAMPAIGN

Anion Hill

C/S-80 $15.

C/Appla '. . . .$15

C/Pet $15

PLANET MINERS

Avilon Hill

C/S-80 $15.

C/Appla $15

C/Pet $15.

NINE GAMES FOR PRE-SCHOOL CHILDREN

try Bwrgi Blank

16K. . S-80 $9.95

KEYBOARD VIDEO PRINTER EXTENDER (KVP) by Unco Mkklui

0/16. . S-80 $19.95

C/4. ..S-80 $14.95

RPN CALCULATOR

by Hunil Starkly

C/16. .S-80 $9.95

STBO-UC by Linca Mkkhii

4/M. .S-80 $24.95

ST-BOD SMART TERMINAL

byLancaMkklui

C/16. .S-80 $49.95

0/32. . S-80 $79.95

STAO

by Paul Van dar El|k

16/M. . S-80 $24.95

TINY COMP

by David Boftlke

D/32. .S-80

STAR TREK

by Lanca Mlcklus

C/16. .S-80

APL80

by Phelps Galas

D. . S-80

C. . S-BD

TRS-80* MEMORY DIAGNOSTIC

by Dive Stambaugh

D/16. . S-BO

KRIEGSPIEL II

by Ron Potkin

C/16. . S-80

UP PERISCOPE

CCA-OM

Panonil Soltwirl

C/S-80 $74.95

C/Apple $99.95

DESK TOP PLANNER

Panonil Sottwin

O/Appla $99.95

MONTY

Panonil Sottwin

C/S-BO $24.95

C/Apple $27.95

D/S-BO $27.95

D/Appla $27.95

LEVEL III BASIC

Mlcroiott

C/S-80 $49.95

MuMATH

Mlcrololt

D/S-BO $74.95

EDITOR-ASSEMBLER

Mlcroioll

C/S-80 $29.95

OLYMPIC DECATHLON

Mttroiotl

C/S-BO $24.95

D/S-80 $24.95

BASIC COMPILER

D/S-80 $195.00

ADVENTURE MICROSOFT

D/S-80. . . FORTRAN

D/S-BO

NEWDOS 80

Apparal

SCREEN MACHINE

Settip* Inc.

C/Apple $19.95

D/Apple $29.95

APPLE TALKER

Soltapa Inc.

C/Apple $15.95

DUNGEON CAMPAIGN

Synergistic Soltwirl

O/ApplB $17.50

C/Apple $14.95

WILDERNESS & DUNGEON CAMPAIGN

Symrglitlc Sollwin

D/Apple $32.50

WILDERNESS CAMPAIGN

Synarglitlc Software

C/Apple $17.50

D/Apple S19.95

ODYSSEY

Synirglillc Sottwin

D/Apple $29.95

HIGHER TEXT

Synergistic Software D/Appla

C/16 . S-80 X-WING II

by Chris Fraund

C/16. .S-80. .

HIGHER GRAPHIC

Synergistic Software

D/Apple $24.35

MODIFIABLE DATA BASE

MAILING LIST DATA BASE

Syi

D/Apple $34.50

PROGRAM LINE EDITOR

Synergistic Software

D/Apple $40.00

BISMARCK

Strategic Si

C/S-80 $49.95

D/S-80 $59.95

D/Apple $59.95

MORLOC'S TOWER

11 rtlPLE OF APSHAI •lions

C/S-80. $24.95

C/Pet $24.95

D/S-80 $29.95

D/Apple $29.95

DATESTONES OF RYN

.jtomited Simulations

D/S-80 $19.95

D/Apple $19.95

C/S-80 $14.95

C/Apple $14.95

C/Pel $14.95

FORTE

Solupo inc

C/Apple $19.95

INVASION OF ORION

Aulomitld Slmulltloni

D/S-BO $24.95

D/Apple $24.95

C/S-80 $19.95

C/Apple $19.95

C/Pel $19.95

AOVENTURELANO

Adventure Intarnatlonel

C/S-BO $14.95

C/Apple $14.95

PIRATE'S COVE

Adventure Internetlcml

C/S-80 $14.95

C/Apple $14.95

MISSION IMPOSSIBLE

Adventure Intermtlenel

C/S-BO $14.95

C/Apple $14.95

MYSTERY FUN HOUSE

Adventure Inlernitlonil

C/S-BO $14.95

C/Apple $14.95

SUPER TEXT II

Mnta UnHmire.

D/Apple . .$150.00

THE VOICE

Muse Software

D/Apple $39.95

U-ORAW II

Musa Software

D/Apple $39.95

APPILOT II EDU-DISK

Muse Softwere

D/Apple $99.95

BEST OF BISHOP

Softapa Inc

D/Appla $39.95

EDITOR ASSEMBLER

Hayden Software

O/Apple $49.95

SUPER APPLE BASIC

SARGON II

Heyden Sottwin

D/S-80 $34.95

D/Apple $34.95

C/S-BO $29.95

C/Apple $29.95

AIR TRAFFIC CONTROLLER

Sansallonel Softwere

C/S-80 $9.95

C/Apple $9.95

SUPER INVASION

Semitlonil Softwere

C/Apple $19.95

SPACE WAR/SUPER INVASION

Sentltlonel Software

O/Apple $29.95

DATA FACTORY

Micro Lob

O/Apple $100.00

DOGFIGHT

Micro Lib

O/Apple $29.95

C/S-80

C/Apple

C/Pel

B-1 BOMBER

NORTH ATLANTIC CONVI

INTRODUCTION TO PROGRAMMING IN BASI.

C/Atari

3 D TIC TAC TOE

CHESS

Atari

C/Atarl $39.f

STAR RAIDERS

Atari

C/Atarl $15.1

SUPER BREAKOUT

Atlfl

C/Atarl $39.!

EDITOR ASSEMBLER

Atari

C/Atarl $15.!

VIDEO EASEL

Atari

C/Atarl $39.!

INVESTMENT PORTFOLIO

Small Sylliml Sottwin

C/S-BO $49.!

WALL STREET CHALLEN

Image Computer Products

C/Atarl $14.:

WARPATH by Hen Potkin C/16. S-80 $14.95

MAGIC PAINTBRUSH

Mark Pelciirikl

D/32/A ROM $29.95

THREE-D GRAPHICS

Mirk Palezirekl

0/4B/A ROM $29.95

PORK BARREL

Beat pa Blink

C/16 /A $9.95

AUTOMATED DISK DIRECTORY

Bamware

C/|2]/32/S-B0 $19.95

PATHWAYS THROUGH THE

ROM

SdtlSkJaPublkjThtni

plua $1. shipping . . .$19.95

VISICALC

Pereonel Softwere

O/Apple $149.95

O/Atarl $199.95

INTERLUDE

Syntonic Softwere

C/S-80 $16.95

C/Apple $16.95

D/S-80 $19.95

O/Apple $19.95

SPECIAL DELIVERY EXTRACT

fluellty Software Dtitrlbuton

O/S-80 $125.00

FORTH II

Softapa Inc.

D/Apple $49.95

APPLE LISTENER

Softapa Inc.

C/Apple $19.95

T SHORT

Web Internetlenel

C/S-BO 19 95

ULTRA MON

Intarpro

C/S-80 $24.95

AMBUSH

Strategic Slmulltlom

D/Apple $59.95

BASKETBALL Atari

C/Atarl $39.95

MUSIC COMPOSER

Atari

C/Atarl $59.95

BLACKJACK

Atari

C/Atarl $14.95

HANGMAN IN BASIC

Atari

C/Atarl $14.95

PYRAMID OF DOOM

C/S-BO $14.95

C/ApplB $14.95

VOODOO CASTLE

C/S-80 $14.95

C/Apple $14.95

THE COUNT

Adventure inlernetlonal

C/S-80 $14.95

C/Apple $14.95

STRANGE ODYSSEY

C/S-80 $14.95

C/Apple $14.95

FIN-PLAN

Hiydan Software

D/S-80 $74.95

SCRIPSIT

HadlO Shark

C/S-80 $65.00

D/S-BO $95.00

SOFT MUSIC

D/S-80 $150.00

GALACTIC EMPIRE

Broderbund Software

D/Apple $24.95

GALACTIC REVOLUTION

Broderbund Software

D/Apple $24.95

GALACTIC TRADER

D/Apple $24.95

ASTEROIDS IN SPACE

Quality Soilware

O/Apple $19.95

FASTGAMMON

Duality Software

C/S-80 $19.95

C/Appla $19.95

MIND MASTER

C/Atari $14.9

SKILL BUILDER I

t Products

C/Atari $19.9

STRATEGY PACK I

tmage Computer Products

C/Atari $19.9!

STRATEGY PACK II

Image Computer Products

C/Atari $19.9

ALL STAR BASEBALL

Circle 130 on inquiry card.

Model-ll, 64K RAM Model-Ill, 16K RAM Model-Ill, 32K Dual Disk Pocket Computer v*7 Interface TRS-80 Color Computer TRS-80 Color Computer Expanded CQMM-80 Interface CHATTER BOX Interface DISK-BO Interface Expansion Interface, no RAM Expansion Interface, 16K RAM Expansion Interface, 32K RAM RS-232-C Board TRS-232 Printer Interface 16K Memory Kit, TRS-keypad 16K Memory Kit, TRS-Exp. Int.

OUR PRICE

LIST PRICE

$3899.00

$3599.00

- $999.00

$929.00

$2495.00

$2299.00

$298.95

$263.00

0 $399.00

$359.00

$599.00

$519.00

$179.00

$159.95

$259.95

$349.95

$329.95

$299.00

$279.00

$418.00

$339.00

$537.00

$399.00

$99.00

$89.00

$59.95

$119.00

$5'9.00

$119.00

$59.00

ATARI 800

$849.00

ATARI 400

$529.00

ATARI' JACC 16K RAM $149.00 AXLON 32K RAM $259.00

APPLE II* or APPLE II+ 48K $1119.00

TRS-80*

COLOR COMPUTER

4K $359.00

16K with extended

BASIC $519.00

TRS-80* MODEL III

16K $929.00 32K with two drives $2299.00

OUR PRICE

LIST PRICE

Upper/lower Mod Kit

$59.00

$24.95

Video Reverse Kit

$23.95

CPU Speed-up Kit

$24.95

Percom Electric Crayon, w/cable

$279.95

TRS-80 Dust Cover (3pc set),M0D-l

$9.95

$7.95

TRS-80 Computer Case

$109.00

$99.95

TRS-80 Monitor Case

$84.00

$84.00

Percom, TFD-100, 40-track

$429.95

$399.00

Percom, Dual TFD-100 Drives

$849.00

$799.00

Percom, TFD-40, 40-track

$399.95

$379.00

Percom, TFD-200, 77-track

$675.00

$629.00

Hardside, 40-track Disk Drive

$389.00

$329.00

Percom Data Separator

$29.95

Extender Cable

$15.95

2-Drive Cable

$29.95

$29.00

4-Drive Cable

$39.95

$39.00

PMC-80

Personal Microcomputers

A "work-alike" computer to the TRS-80* Model I,Level II.Complete Level II, 12K BASIC ROM by Microsoft. 100°'d software compatible with Radio Shack programs and other independent suppliers. Built-in cassette player. Will operate with any Radio Shack peripherals and others. Interface Adapter permits Expansion Interface with memory expansion to 48K to be added. Expansion Interface will also permit the addition of Radio Shack compatible 5V«" disk and disk operating systems, RS-232, printers, etc. Reg. $645.

OUR LOW $599.

DISK-80

Disk Controller (up to 4 drives)

Data Separator

Incl. 16K of RAM

Provision for an additional 16K RAM

TRS-BUS Connector for future expansion

ONLY $339.00

PRINTERS

Microline-80 $599.00

Microline-82 $769.00

Epson MX-80 $569.00

Centronics 737 $839.00

Vista V300 $1799.00

HARDWARE ITEMS ONLY:

TERMS: Prices ind speculations in tubject to changi HARDSIDE iccapti VISA & MASTERCARD, Certified checks end Money Orders; Personal checks accepted (takes 3 weeks to clear) HARDSIDE pays all shipping charges (within the 48 atatea) on all PREPAID orders OVER S100.00.On all orders under S100 a S2.50 handling charge must be added. COD orders accepted (orders over $250 require 25^0 deposit) there la a 55.00 handling charge. UPS Blue Label, and Air Freight available at extra cost.

■TRS-80, APPLE and ATARI are trademarks ol Tandy, Apple Computer Co., and Warner Communication, respectively.

iO

JJJJJJJA

T5€:HPRD5ID€

6 South St .Milford, NH 03055 (603)673-5144 TOLL FREE OUT-OF-STATE 1-800-258-1790

Circle 131 on inquiry card.

Technical Forum

Build a Null Modem

Robert Haar, 1675 Thetford Rd, Towson MD 21204

When connecting computers, terminals, and communication equipment, it is sometimes useful to have a device called a null modem. To understand what a null modem is and why you might need one, it is first necessary to know what a modem does and what is meant by the term RS-232C serial interface.

Modems

You probably have some idea of what a modem does. It allows computers and terminals to communicate over phone lines. This is done by converting serial binary data (individual bits transmitted one bit at a time) into audible tones that can be sent over normal telephone lines. Another modem at the opposite end translates these tones back into a stream of bits, which is then regrouped into 8-bit bytes. Figure 1 is a diagram of this setup. The most common type of modem is called Bell 103A compatible.

RS-232C Serial Interface

The term RS-232C refers to a standard that specifies the connection between a modem and either a computer or a terminal, covering the physical, electrical, and functional aspects of that interface. We are most familiar with the physical side of this standard since it describes the ubiquitous 25-pin D-shaped connector (the DB-25) that is used on most terminals and computer serial I/O (input/output) ports. The electrical aspects of the standard specify what kind of electrical signals can be applied to the pins of such a connection. The functional part says what the signals on each pin are supposed to mean.

The modems shown in figure 1 are called DCE (datacommunication equipment), while both the terminal and the computer are called DTE (data-terminal equipment). It makes no difference whether a unit is a terminal, a computer, or anything else—if it connects to a modem, it is DTE. One pin in the RS-232C connector is designated as a transmit-data line. This pin carries serial data from the DTE to the modem (DCE). Another pin is called receive-data, and its data goes in the other direction. It is important to note that the transmit/receive designation is always defined in reference to the DTE-to-DCE connection.

Technical Forum is a feature intended as an interactive dialog on the technology of personal computing. The subject matter is open-ended, and the intent is to foster discussion and communication among readers of BYTE. We ask that all correspondents supply their full names and addresses to be printed with their commentaries. We also ask that correspondents supply their telephone numbers, which will not be printed.

Null Modems

The name "null modem" suggests a black box that looks like a modem but doesn't do anything. To see why you would need an "empty" modem, suppose that the terminal and the computer shown in figure 1 are in the same room and you wish to connect them together. You might be able to physically connect them if you have a cable with a DB-25P plug (male connector) on the end and the other has a corresponding socket, the DB-25S. But if both of them have been wired to connect to modems, you have a problem. Both will be sending information on the same transmit-data pin and both will be expecting to receive data from the other on the same receive-data pin. This would be equivalent to the effect of talking to someone on the telephone while the telephone handset is upside down. It just won't work.

The simplest variety of null modem cross-connects the transmit- and receive-data lines as well as connecting the ground pins, which are required to establish a voltage reference for the other signals. In many instances, this is all you will need to allow the terminal and computer to talk to each other. In some cases, either the terminal or the computer requires other signals in addition to the data and ground lines. Table 1 lists the most commonly used pins in the RS-232C interface, along with their usual abbreviations and meanings.

Pin Number and

Name

Function

1 (AA)

FG (frame ground), protective ground

connection.

2 (BA)

TD (transmit data), from DTE to DCE.

3 (BB)

RD (receive data), DCE to DTE.

4 (CA)

RTS (request to send), the DTE asking

permission to send to the DCE.

5 (CB)

CTS (clear to send), the DCE granting

transmit permission.

6 (CC)

DSR (data set ready), indicates that the

DCE is powered up.

7 (AB)

SG (signal ground), ground reference for

the TD and RD signals.

15 (DB)

TC (transmit clock), clock used to

generate the serial transmitted data

(DCE to DTE).

17 (DD)

RC (receive clock), clock for received

data (DCE to DTE).

20 (CD)

DTR (data terminal ready), indicates that

the DTE is powered up.

22 (CE)

Rl (ring indicator), says that the incom

ing phone line is ringing; used with

modems with answer capability.

24 (DA)

XTC (external transmit clock), like TC but

from the DTE to the DCE.

Table 1: Summary

of RS-232C serial interface connections

and their function.

198 February 1981 © BYTE Publications Inc

When You Have To Face A Deadline

Arm Yourself With Pascal/M f+

You know what a monster a deadline can be ifyouhaveto face it without the proper tools. Arm yourself with an integrated set of programs, designed from the beginning for production use, all tuned to the single goal of producing reliable software. Pascal/MT+ is a fully integrated program production system including our compiler, debugger, disassembler and linker.

Used by many companies, large and small, Pascal/MT+ produces highquality reliable products in an amazingly short amount of time. Our run-time library contains all the tools needed to begin program construction immediately. Pascal/MT+ produces efficient, small native machine code demanded by today's product developers. All of our library routines and features work exactly the same on 16-bit systems as they do on 8-bit systems so you can increase your capability without rewriting any of your software. Your production quality products demand production quality tools. Order Pascal/MT+ now, call us today!

Payment Terms:

Cash, Check, UPS, C.O.D.

Mastercard, VISA,

Company P.O.

Pascal/MT+ Features:

An International Standard:

Pascal/YT+ conforms to the ISO Standard for Pascal, our competition doesn't even come close! A report on the performance of Pascal/MT+ on the Pascal validation suite is included with each compiler.

Modular Program Compilation:

The Pascal/MT+ modular compilation mechanism allows construction of fully coupled modules and programs allowing the modularization of large programs without any sacrifice in either space or time efficiency.

Efficient Native Code:

All versions of Pascal/MT+ produce efficient, compact NATIVE OBJECT CODE. In an independent benchmark Pascal/MT+ outperformed all other Pascal compilers on our target machines. In addition it produced the smallest final programs by including only the minimum run-time overhead necessary.

Circle 132 on Inquiry card.

/ MT Micro SYSTEMS \

1562 Kings Cross Drive Cardiff, California 92007 (714) 755-1366

Totally Portable:

Pascal/MT+ has been designed from the beginning to generate code for many different microprocessors. Pascal/MT+ programs you create today can bere-compiled to run on a more powerful machine tomorrow. All of the extended language features are present in every version of the compiler. This means you won't have to start over when the customer demands more, more and more.

Extensions:

Pascal/MT+ has many extensions to the Pascal language too numerous to describe in detail here. Our 160 page user's guide describes the features and gives examples of how to use them. A short summary of features is listed below: dynamic strings, BCD and Floating point reals, AMD9511 support, bit, byte and unsigned word manipulation, I/O port access, afull implementation of the NEW and DISPOSE heap and many others.

Target Machines:

Available now 8080, 8085 and Z80

Available soon 8086, 8088

Coming 68000, 6809 and Z8000

Pricing:

8080/Z80 - $250.00 Others Call

Communicalion Arts. Hunlington Beach. CA

Technical Forum,

TERMINAL

MODEM

PHONE "LINE

MODEM

COMPUTER

Figure 1: Diagram of a typical setup that allows a terminal to communicate with a computer over standard telephone lines. The modems shown are called DCE, or data-communication equipment, while both the terminal and the computer are called DTE, or data-terminal equipment. When referring to the RS232C serial interface, the transmit/receive designation is always defined in terms of a DTE-to-DCE connection.

Many terminals and computer serial I/O circuits generate the request-to-send and data-terminal-ready signals and expect to receive the corresponding signals clear-to-send and data-set-ready back from the modem. If these are not turned on, the DTE will not allow itself to transmit or receive data. If you plug together two pieces of equipment, both of which are configured as DTE, their data-terminal-ready and request-to-send signals will be connected together, and neither will know how to get the required data-set-ready or clear-to-send acknowledgments. Again, the solution is to cross-connect the corresponding signals so that the DTR signal output of one device goes to the ready DSR input of the other and each unit's RTS signal goes to its own CTS input.

The clock signals listed in table 1 are rarely used. If you need them, cross-connect them. Sometimes a device will need the ring indicator from a modem before it will start accepting incoming data. This can be obtained by connecting this pin to the DTR pin of the other device.

FORTH for CP/Mt

Conquer the wait while the editor or compiler loads. Conquer excessive disk I/O. Conquer boredom during yet another compilation or assembly just to squash a tiny bug. Conquer memory squeeze on application programs.

Tim in Engineering now offers CP/M users a complete, integrated, memory resident full FORTH system. Powerful editor. Incremental FORTH compiler. Z80/8080 assembler. Virtual memory. Fast .17 second/K-byte disk I/O. Top level command processor. All using your standard CP/M BIOS.

Ready to run for only $95. User Manual alone, $20, credits toward software purchase.

Place your order today — Then go FORTH and conquer!

^

2A

MITCHELL E.TIMIN ENGINEERING COMPANY

9575 GENESEE AVENUE ■ SUITE E2 ■ SAN DIEGO ■ CALIFORNIA 92121

TELEPHONE (711) 455-9008

VISA

^

&

^

CONNECTOR A PIN NUMBER

1

IFG)

2

(TD)

3

(RD)

4

(RTS)

5

(CTS)

8

(CD)

7

(SG)

22

(Rl)

6

(DSR)

20

(DTR)

CONNECTOR B PIN NUMBER

X

n

1 (FG)

2 (TD)

3 (RD)

4 (RTS)

5 (CTS) 8 (CD) 7 (SG) 22 (Rl)

6 (DSR)

20 (DTR )

(jrnuii. jdd iiS Itemi shipped w.ttiln 46 kiDuii for C OD... ■FORTH InlerctlCrOup '••ip.ilal Rnra'chCorp

Figure 2: The interconnection scheme for a null modem. A null modem is a "black box" that allows two pieces of data-terminal equipment to communicate with each other when a phone line is not required (such as when they are in the same room). If the two pieces of equipment were connected without the use of a null modem, both would be sending information on the same RS-232C connector pin and also would expect to receive data on the same pin.

Construction

Figure 2 is a diagram of an interconnection scheme that works in most cases. If you need a different set of signals, it may be modified; table 1 provides the necessary information. In some cases you will need to connect a device that requires the DSR control signal to another that doesn't generate the corresponding DTR signal. In this event, connect the DSR pin of the first device to its own DTR pin.

If you buy one of the commercially produced null modems, you will probably get a box about the size of a large paperback book, with two female connectors (DB-25S sockets). I found it more convenient to use one male and one female connector, because their pin numbers are mirror images of each other. Placing them back-to-back lines up all the pins with the same number. I bolted one-inch separators between the screw holes of the two connectors to hold them in place and then wired the connections as shown in figure 2. I wrapped the whole thing in electrical tape to seal it. The result is a much smaller package than the commercial product. It can easily be attached to the end of the RS-232C cable and left there.

Keeping to my practice of documenting whatever I produce, I drew a diagram like figure 2 on adhesive label material and placed it on the null modem's cover. If in the future I need to know which pins are connected, I won't have to remove the covering or hunt through my files for the circuit description. It is always right there.

For Further Research

If you would like more comprehensive information on this subject, consult chapter 26 of the book Technical Aspects of Data Communication by John McNamara, published by Digital Press. ■

200 February 1981 © BYTE Publications Inc

Circle 133 on Inquiry card.

LOWEST PRICE - BEST QUALITY

NORTH STAR

North Star Horizon 2

2-6% Disk Drives 32K Double Den Factory assem. & tested Factory guaranteed List 3095

only

$2274

POWERFUL NORTH STAR BASIC FREE SUPERB FOR BUSINESS & SCIENCE

FACTORY ASSEMBLED & TESTED LIST ONLY

HORIZON-1-32K-DOUBLE DEN $2695 $1980

HORIZON-2-32K-QUAD DENSITY 3595 2674

HORIZON-2-64K-QUAD + HARD DISK 9329 7149

HORIZON RAM ASSM 16K=$389. 32K = $579

HORIZON RAM KIT SALE1 16K = $314 32K = S469

HORIZONDISKDRIVESALEDOUBDEN SAVE! 315

NORTH STAR HARD DISK 18 Mb 4999 $3929

PASCAL-PLUS 14,18 OR 36 DIGIT PRECISION 249

SUPERBRAIN

ZENITH

SUPERBRAIN QD 64K

List $3995 only $2995

Z-89 48K

List $2895 only $2299

TERMINALS Z-19 $725

INTERTUBEIII omy$725

DIP-81 PRINTER omy$395

MICROTEK $675

NEC PRINTER $2569 TRACTOR, THIMBLE, RIBBON

InterSystems

ITHACA INTERSYSTEMS 2A

List $3595 You Pay Only

Z-BOACPU 4 MHz 64K Dynamic RAM Front panel V I/O—with Interrupts FDCII Disk Controller 20 slot motherboard

$2795

PASCAUZ + THE FASTEST PASCAL $375

GET READY FOR ITHACA'S Z-B000

8086 16 BIT CPU & SUPPORT CARD SEATTLE $575

MORROW 8" DISK

DISCUS 2D + CP/M® 600K ONLY $938 DISCUS 2 + 2 + CP/M® 1.2 MEGA B. $1259 ADD DRIVES 2D = $650 2 + 2 = $975 2D-DUAL + CP/M® + MICROSOFT BASIC = $1555 $2293 VALUE OVER 32% OFF!

WHILE THEY LAST

MORROW HARD DISK

26,000,000 BYTES!!

LIST $4995 ONLY $3995

CP/M® IS INCLUDED!

SAVE ON MEMORY AND PROGRAMS

SYSTEMS MEMORY 64K A & T 4mHz

$599 SYSTEMS MEMORY 64K BANK SELECT 1789 CENTRAL DATA 64K RAM $599

ITHACA MEMORY 8,'16-blt 64K $845

SEATTLE MEMORY 8/16 BIT 16K 4Mhz $275 SSM KITS Z-80 CPU $221

VIDE0BRDV834Mhz $412

ANADEX PRINTER DP-9500-1 $1349

CAT NOVATION MODEM $169

TARBELL DISK CONTROLLER DO $445 ECONORAM2A8KASSM $179

NSSE 1-22 & P01 TERRIFIC PROGRAMS ONLY $10. EACH NORTHWORD 294 MAILMAN 234 INFOMAN $364

TARBELL COMPUTER-PHONE

RCA-COSMACVP-111 99 RCA-COSMAC VP-711 $199

COLORIRAINBOW385 SPECTRUM $289

EZ-80 Machine Language Tutor $25 EZ-CODER Translates English to BASIC $71 ECOSOFT FULL ACCOUNTING PKG

$315 BOX OF DISKETTES $29

SECRETARY WORD PROCESSOR

The Bestl $99 TEXTWRITER III Book Writing Program

$112 GOFAST NORTH STAR BASIC Speeder Upper$71 Which Computers are BEST? BROCHURE FREE

North Star Documentation refundable W/HRZS20

AMERICAN SQUARE COMPUTERS BEATS ADV. PRICES

square

American [j|j] Computers

919-889-4577 KIVETT DR. JAMESTOWN N.C. 27282 919-883-1105

CP/M Is a registered trademark of Digital Research, Inc.

Circle 134 on inquiry card.

BYTE February 1981

201

Software Review

IRV, a TRS-80 Utility Program

Teri Li, POB 481, Peterborough NH 03458

IRV is a new machine-language utility program for the BASIC programmer. It supplies features that all programmers will appreciate, and it uses less than 1 K bytes of programmable memory (unless you add to its definitions).

IRV gives you a flashing cursor, auto repeat on any key held down for more than one second, and keyboard control of the cassette remote plug (you can turn the cassette motor on and off simply by hitting shift-clear). [In this review, words in italics refer to keys of the same name as those on the TRS-80 keyboard....GW] This is followed by the ability to define any key to your chosen definition. As sold by The Programmer's Guild, all of the shifted alphabetic keys are defined as BASIC keyword commands (see table 1); this duplicates features of the utility program called T-Short.

However, if you don't like any of the provided definitions, you can easily change them by pressing the shift

Computers Terminals Modems

We are the stocking terminal distributor offering full service, laintenance coverage.

CRTs

Perkin-Elmer Bantam 550B

$694

Microterm Mime HA

$819

NEW! 550E

755

Televideo912C

799

NEW! 550S

879

Televideo 920C

839

Perkin-Elmer 1251

1564

IBM 3101 Model 10

1191

DECVT100

1668

Model20

1375

Microlerm ACT VA

779

Hardcopy Terminals

DECLA34DA

$939

Teletype Model 43 KSR

$999

DEC LA34AA

1095

with RS232 & 7' connector

DECLA120

2338

NEC Spinwriter 5520 typewriter quality with tractor, ribbon & thimble

3088

Printers

Perkin-Elmer 650/655

$899

Centronics 779

$1068

screen printer, 100 CPS

NEC Spinwriter 5510

2754

MicrolineSO

594

typewriter quality with

Centronics 737

837

tractor, ribbon & thimble

Modems

Bell212A — Penril 300/1200

$799

Bell103/113 — USR-330A

$399

1200 and 300 baud/manual

300 baud. Auto-dial/ Auto

originate, autoanswer

onginate/Auto-answer.

Auto-dialoptionfor

799

USR-330D 300 baud. Manua

339

300/1200

originate/Auto-answer.

All modems connect to phone

line via

RJ11C standard extension phone

jack.

Acoustic Coupler

Computers

Phone Link—300 baud.

$179

USR-1600P

$4099

Originate/answer. Compact

Leasing rates on request. Write or call for product Information. 10 day money back guarantee on all products.

m

U.S. ROBOTICS inc.

203 N. WABASH SUITE 1718 CHICAGO, ILL 60601 (312) 346-5650

and down-arrow keys, followed by the shift (alpha) key you want to redefine. When you have finished defining, press the shift-down-arrow combination once more. (Hitting enter merely inserts a carriage return into the definition.) This ability to redefine is not restricted to alpha keys: it extends to all of the keys on the keyboard, except for the shift keys and the shift-down-arrow key combination. This means that you can redefine both the break and enter keys!

How is this possible? Simple: IRV pokes new addresses into the keyboard Device Control Blocks used by the TRS-80. The new addresses point to IRV, which is in high memory. IRV processes each input keystroke before calling routines in read-only memory. This gives IRV its great power and versatility.

If you decide that you don't want the programmedkeys mode in operation, you can turn this feature off by hitting shift-down-arrow twice. To turn it back on, hit the shift-down-arrow twice again.

The usefulness of these definable keys is not restricted to single BASIC commands; you can actually define a key as any message, command, or series of commands up to a maximum length of 255 characters. This is true for all of the keys. If you were to exercise this option to its fullest, you would fill almost 25 K bytes of programmable memory (100 keys, uppercase and lowercase, times 255 characters per key).

Yes, one keystroke can represent a series of commands. Hitting enter inserts a carriage return but does not end the

Name: IRV

Language:

Z80 machine language

Type:

BASIC utility

Manufacturer:

The Programmer's Guild

POB 66

Peterborough NH 03458

Computer:

Radio Shack TRS-80, Model I with Level II BASIC and 16 K bytes or more of memory (disk drive optional for cassette version only)

Price:

Cassette $24.95 Disk $29.95

Documentation:

5-page booklet, 14 by 22 cm (5Vi by 8Yi in)

Format:

Cassette or 5-inch floppy disk

Audience:

BASIC programmers

202 February 1981 © BYTE Publications Inc

Circle 135 on Inquiry card.

COfTlPUTERS?

NO WAY WITHOUT KNOW-HOW.

COMPUTER GAMES

MICROCOMPUTER INTERFACING

MACHINE

AND

ASSEMBLY

LANGUAGE

PROGRAMMING

Of THE

PtHMI

'

J. Victor Nahigian William Hodges

Exciting collection of computer games written in 8K of memory BASIC including: Blackjack, Boggle, Escape, Golf, Poker, StarTrekand more, paper $10.95

Bruce Artwick

Nine chapters include: selecting the right microprocessor, microcomputing input and output, interface components and their characteristics, plus much, much more, cloth $21.95

MACHINE & ASSEMBLY LANGUAGE PROGRAMMING OF THE PDP-11

Arthur Gill

Explains the basic organizational features of the PDP-11, including machine and assembly techniques, cloth $19.95

PASCAL

PROGRAMMING

STRUCTURES

ProgriMTimirtsStrwtyres

\|_r.

G*«9* iJAChwry

Joseph Carr

All-in-one guide to Z80 pin definitions, CPU control signals, support chips, interfacing peripherals, and more. paper$10.95

George Cherry

The exceptional features of this book include: the whole-part method of language instruction, a mnemonic device for remembering the skeleton of a Pascal program, plus much more, cloth $16.95

W.K.Giloi

Part I is devoted to data structures and algorithms, including the subject and chapters on data structures, data bases, and list handling. Part II emphasizes languages and their interpreters, cloth $22.95

To order books by phone, call toll free:

1-800-228-2022

(In Alaska: 1-907-276-3242; in Nebraska 1-402-571-4900;

in Carolina (Puerto Rico): 1-809-752-1275, during store hours only).

All books not available in all stores.

INTERACTIVE COMPUTER GRAPHICS

America's Favorite Bookseller

)Jfct

Circle 136 on Inquiry card.

BYTE February 1981 203

Circle 137 on Inquiry card.

BUSINESS SOFTWARE

HIGH-QUALITY COMMERCIAL GRADE PRODUCTS

SIMPLE DOCUMENTATION AND OPERATION

END-USER HOTLINE AND NEWSLETTER

RUNS UNDER CP/M AND CBASIC-2 IN 48K... ALL SYSTEMS WILL INTERFACE TO LEDGER.

DESIGNED FOR VERY HEAVY OFFICE USE... '

REGULAR UPDATE SERVICES ARE AVAILABLE

COMPLETE COMPUTER SYSTEMS AVAILABLE..

' HANDLES BOTH FLOPPY DISKS i HARD DISK '

' RUNS PERFECTLY ON 64K TANDY MODEL II.

INSURANCE AGENCY - FOR INDEPENDENT AGENCIES HANDLING DIFFERENT LINES FROM SEVERAL UNDERWRITERS. AUTOMATIC POLICY CREATIONS, RENEWALS, INVOICING AND POSTING OF

COMMISSIONS BY PRODUCER, CLASS, UNDERWRITER, AND CLIENT. HAS DIRECT AND AGENCY BILLED STATEMENTS PLUS DETAILED REPORTS AND LOSS HISTORY FILE.

MlDICAL MANAGEMENT - FOR SMALL TO MEDIUM CLINICS. PATIENT MASTER, HISTORY, TICKET ,

AND SCHEDULING FILES. HANDLES ICDA-9 DIAGNOSIS CODES AND CPT-4 PROCEDURE CODES WITH

STANDARD OFFICE CHARGES. AUTOMATIC MONTHLY STATEMENTS AND PRINTING OF AMA INSURANCE FORMS AS WELL AS OVER TWENTY DIFFERENT OTHER REPORTS.

DIUTAL MANAGEMENT - SIMILAR TO MEDICAL EXCEPT DESIGNED FOR ADA PROCEDURE CODES AND CHARGES AND STANDARD ADA INSURANCE FORM. BOTH SYSTEMS HAVE A FORMS MENU FOR PRINTING ADDITIONAL STATE AND LOCAL INSURANCE FORMS AS WELL AS SPECIAL STATEMENTS.

LEGAL TIME ACCOUNTING - FOR LAW OFFICES. HANDLES CLIENT FILES AND BILLING,

APPOINTMENT SCHEDULING, AND COMPLETE CASE HISTORY FILES CATEGORIZED BY CASE TYPE, CLIENT, ATTORNEY, CASE NUMBER, AND DATE. HAS AUTOMATIC DEFAULT FOR STANDARD FLAT RATE OR HOURLY CHARGES BY CLASS OF CASE WITH MONTHLY ANALYSIS OF TIME SPENT BY EACH ATTORNEY IN EACH CATEGORY. LINKS FOR PRINTING STANDARD LEGAL FORMS ALSO PROVIDED.

RIAL-ESTATE MULTI-LIST - COMPLETE HANDLING OF NORMAL DAILY FUNCTIONS OF AGENCY, INCLUDING PRODUCTION REPORTS OF MTD AND YTD SALES AND COMMISSIONS BY SALESMAN. HAS FULL MULTI-LISTING DATABASE SYSTEM FOR EASY VIDEO SELECTIONS OF ALL PROPERTY MEETING SPECIFIC PARAMETERS. MANY ANALYSIS REPORTS AVAILABLE,INCLUDING PROJECTED MORTGAGE PAYMENTS. LINKS PROVIDED FOR PRINTING STANDARD REAL-ESTATE FORMS.

PLUS GENERAL LEDGER, ACCOUNTS PAYABLE, ACCOUNTS RECEIVABLE, PAYROLL, INVENTORY, ONLINE ORDER ENTRY, REAL ESTATE MULTI-LIST, FINANCIAL ANALYSIS, TAX PREPARATION, FULLYINTEGRATED WORDPROCESSING, DATA BASE MANAGEMENT, CP/M FOR MODEL II, AND MUCH MOREI

UNIVAIR. INC.

PROtTSSlONAl. SERVICES YOU CAM DEPEND ON!

ADDRESS i 10 3 2 7 LAMBERT INTERNATIONAL AIRPORT, ST. LOUIS MO. 63145 USA

TELEPHONE 314-426-1099 MASTERCHARGE AND VISA CARDS ARE ACCEPTED I

PROGRAM MANUALS - $20 CREDITED TOWARD PURCHASE CATALOG - $5 IMMEDIATE SHIPMENTSI

o o o o

o o o

0

o o o o o o

o o

o

o

BUY COMPUTERS BY MAIL ORDER AND SAVE 16%

APPLE HARDWARE

16K 32K 48K Disk with Controller

S 958.00 $1,040.00 S1.099.00

495.00 440.00 445.00 655.00 215.00

Disk Pascal

Graphics Tablet Symtek Light Pen Versawrlter Digitizer System

S 215.00 Vldex Vldeoterm 80 Column Card $ 315.00 with graphics-ROM $ 335.00 Apple Clock S 225.00

Micro Soft Z-80 Software Card wlthCPM S 319.00

Parallel Printer Card

S 145.00 Communications Card with connecting cable $ 185.00 Apple II Firmware Card

S 149.00 Integer Basic Firmware

S 149.00

SOFTWARE

Controller (General Business System) S 519.00

Cashier (Retail Mgmt & Inventory System) $ 199.00 Apple Post Mailing List

$ 45.00

CROMEMCO

SAVE 16% ON ALL EQUIPMENT

NORTHSTAR

Horlzon-2-32KDD

VERBATIM & MEMOREX

SW

$2,390.00

$ 27.50

PLASTIC BOXES

5V«" S 2.25

8" $ 3.50

Send certified check (regular checks require 2 weeks to clear) or charge to VISA or Master Charge. Customer pays shipping.

MIRO COMPUTERS, INC.

27 Long Meadow Place,South Setauket, L.I., N.Y. 11720

(516) 423-7955 CALL MON.-SAT., 10AM-6PM

O

Keystroke

Result

Keystroke

Result

shift-Q

SYSTEM (enter)

shift-Q

GOTO

shift-W

RND(

shift-H

RIGHT$(

shift-E

ELSE

shift-J

INKEYS

shitt-R

RETURN (enter)

shift-K

CSAVE"

shift-T

THEN

shift-L

CLOAD

shift-Y

LEN(

shift-Z

EDIT

shift-U

USING

shift-X

STR$(

shift-l

INPUT

shift-C

CHR$(

shift-0

ASC(

shift-V

VAL(

shift-P

LPRINT

shift-B

INT(

shift-A

STRING$(

shift-N

NEXT

shift-S

GOSUB

shift-M

MID$(

shift-D

DATA

shift-®

CONT (enter)

shift-F

LEFT$(

shift-right-arrow

TAB(

Table 1: One-keystroke strings supplied with IRV. When

IRV is loa

ded into the TRS-80, any of the

single shifted

keystrokes

shown here will cause its associated string to be

"typed" on

the video display.

(The word "enter" means that

the last character typed is the

same as pressing

the enter key,

thus causing the line to be executed.) These

equivalencies

may be <

•.hanged or deleted by using the character

redefinitior

mode.

definition, so you can actually define one key to execute an entire series of commands when pressed. It will do this while executing either a machine-language or a BASIC program. For example, the back-up routine in TRSDOS (call BACKUP, answer all the questions: date, password, drives used, etc) can be abbreviated to a one-keystroke command. This is convenient, especially if you are duplicating several disks.

One interesting advantage to IRV is that you can define the unshifted as well as the shifted keys. I used this feature to set up my keyboard to simulate the experimental Dvorak typewriter layout. [The Dvorak system is a typewriter with a keyboard layout that increases speed

and accuracy during touch-typing GW] Other

possibilities could include rearranging the keys to accommodate foreign languages that use the standard Roman alphabet, but use letters in frequencies different from English.

At this point, IRV is far superior to T-Short and other keystroke shorthand routines. But IRV does not stop here: it has even more capabilities.

IRV gives you on-screen BASIC line editing similar to the on-screen line-editing features of the Commodore PET. To use this feature, first list your program on the video, then hit the shift-break key combination. The blinking rate of the cursor will change slightly. Now you can use the four arrow keys to move the cursor anywhere you like on the video screen. Full-screen wraparound is supported: if the cursor leaves the screen from the bottom, it will appear at the top of the screen in the same column; leaving the screen to the right will put the cursor on the left of the same line.

Once you have put the cursor on the line in which you are interested, you may type anything you want over the line. If there are too many characters on the line, hitting the clear key will delete 1 character. If you need more room, each time you press the break key one space will be added, over which you may type. Holding down either key for more than one second causes each key to repeat its function as long as the key is depressed.

204 February 1981 © BYTE Publications Inc

Circle 138 on inquiry card.

MODEL

$ DISCOUNT $

MODEL

TRS-8O0®

26-4002

64K 1 Drive

$3440.00

26-4160 1 Drive EXP . $1035.00 26-4161 2 Drive EXP . . 1575.00 26-4162 3 Drive EXP . . 2115.00 26-4501 Gen. Ledger . . . 180.00

26-4502 Inventory 180.00

26-4503 Payroll 360.00

26-4554 Acct. Rec 180.00

26-4701 FoMron 270.00

26-1157A Daily Wheel. 2495.00 26-1158 Daisy Wheel II 1799.00

COMPUTER SPECIALISTS

26-1155 Quick Printer II $187.00

26-1 U5 RS-232 Boord 84.00

26-1140 "O" K Interface 249.00

26-1141 "16" K Interface 359.00

26-1142 "32" K Interface 469.00

26-1160 Mini Disk ■ Drive 0 419.00

26-1161 Mini Disk -Additional 419.00

26-1154 Lineprinter II 699.00

26-1156 Lineprinter III 1799.00

26-1159 Lineprinter IV 859.00

26-1166 Line Printer VI 1080.00

26-1563 Scrlpslt • Disk 79.00

26-1566 Vlslcalc 83.00

26-1562 Profile 72.00

NOTE: Call for ovoll'oblllty of VIDEO TEX, Model III, Color, and other new products.

26-1061 4K I $630.00

26-1062 16K III 888.00

26-1063 32K III

2-Drlves, RS232 2225.00

COLOR

*$wmm

ALL OTHER R.S. SOFTWARE

FURNITURE, STANDS, CABLES

AND ACCESSORIES AT

DISCOUNT FROM

CATALOG PRICE.

CEnTRonics

Fast 100 CPS Centronics

730 Printer $659.00

Text Quality Centronics

737 Printer $819.00

Novation Cat Modem. .$149.00 CCA Data Management

System 72.00

Adventure Games

Games 1 -9 each 14.00

Pocket Computer

Model II Cobol Compi

ler

$360.00

Cobol Run Time Packc

P,e

$36.00

ODDBI

aaaaa

doobd

icacooaacocasJcaeSDjjgjQijij

26-3501 1.9K P.C

26-3503 Cossette l/F..

.$225.00 ... 45.00

14-812 Recorder 72.00

26-3001 4K $360.00

26-3002 16K 540.00

26-3010 Color Video 360.00

26-1206 Recorder 54.00

26-3008 Joysticks 22.50

S Acorn Software Products, Inc.

GAMES:

Allen Invasion $9.00

Stock Market 9.00

Star Trek 9.00

Block'Em 9.00

Tlng-Tong ,, 9,00

UTILITIES:

System Savers 14.00

EDUCATION:

Language Teacher 18.00

FREE: COMPUTER CATALOG UPON REQUEST

1-800-841-0860 Toll Free Order Entry

MJCRQ MANAGEMENT SVSTEMS, INC.

No Taxes on Out Of State Shipments

Immediate Shipment From Stock on Most Items

DOWNTOWN PLAZASHOPPING CENTER

115CSECONDAVE.S.W.

CAIRO, GEORGIA31728

(912) 377-7120 Go. Prions No.

•TKS-S0 ll a r*gllt«r*d trademark at th( Tandy Corp.

R.S. 90 Day Limited Warranty F-48 Form Provided

Largest Inventory In the S.E. U.S.A.

Circle 139 on Inquiry card.

BYTE February 1981 205

Circle 140 on inquiry card.

IEEE-488 To TRS-80* INTERFACE

■ I SCIMIFIC UfiHEKIIC IAHWKS1ES I

MODEl 4tl-*Ot

Everything needed to add powerful GPIB-488

controller capability to TRS-80,

Model 1, Level 2 or DOS

Mod. 488-80B $225.00 + shipping, insurance & lax

SPECIFY DISK OR TAPE

For Model 3 Operation, Contact Factory

SCIENTIFIC ENGINEERING LABORATORIES

11 NEIL DRIVE • OLD BETHPAGE, NEW YORK 11804 TELEPHONE (516) 694-3205

'Trade Mark of Tandy Corp. There is no affiliation between Scientific Engineering Laboratories and Tandy Corporalion or Radio Shack.

DECLSM1 Components

Dependable service at discount prices

Domestic and Export

mini

Computer Suppliers, Inc.

25 Chatham Rd., Summit, N.J. 07901 Since 1973

(201) 277-6150 Telex 13-6476

©Mini Computer Suppliers. Inc. 1979

(a)

FIRST, WRITE A SHORT BASIC PROGRAM TO PUT THIS GRAPHICS FIGURE ON SCREEN

(b)

100 MAN $(1) = " 105 MAN $(2) = "

j j

j j

Figure 1: Use of IRV to directly create graphics in BASIC programs. First write a short BASIC program that creates the shape you want to use. Running this program displays the shape on the video screen, as shown in figure la. Then use the line-editing feature of IRV to create BASIC statements (either PRINT or string-storage statements) that capture the shape, one text line at a time. In figure lb, the shape is stored in two entries of the string array MANS. Later, these graphic characters can be printed out in the same program using PRINT statements.

If you are adding spaces to a line, you will notice that repeated addition of characters does not move the rightmost character down to the next line on the video display—instead, it causes the character to disappear from the screen. Likewise, if you have removed all the characters to the right of the cursor, the first character on the next line does not move up. The reason is that IRV looks only at the line on which the cursor is set.

When the line is set to your liking, hit enter. This transfers the changes you have made in that line to the program. If you list the line, you will be able to see that the changes have been made. Should you discover that a line is misplaced, you can use this line-editing feature to type a new number over the old line number. When you hit enter, the new line will be inserted into its proper place in your program, and the old line will still be in its place. This feature is handy for moving lines around in your programs.

The best advantage of the line-editing feature in IRV is that it may be invoked while in the TRS-80 edit mode. For example, it can be used to string several BASIC statements into one long multiple-statement line. Edit the line as you would normally, but when you are ready to insert, hit shift-break. Now position the cursor over the line that you wish to insert in the line being edited. Use the clear key to remove the line number (you don't want to insert a line number), then hit enter. List the edited line and you will see that both lines have merged: the second line is positioned where you entered the insert mode. Other uses include converting IF...THEN statements to IF...THEN...ELSE statements, or vice versa.

Still another use for the IRV line editor is to put graphics characters directly into PRINT statements. First, use a short graphics routine to draw your figure on the video display. When you've finished with the drawing, enter the IRV line-editing mode. Type a line number

206 Febiuary 1981 © BYTE Publications Inc Circle 141 On Inquiry Card.

ITEM NO. WK-7

CMOS SAFE

IC INSERTION/EXTRACTION KIT

KIT INCLUDES

MOS-1416 14-16 CMOS SAFE INSERTER MOS-242B 24-28 CMOS SAFE INSERTER MOS-40 36-40 CMOS SAFE INSERTER

• EX-1

• EX-2

14-16 EXTRACTOR

24-40 CMOS SAFE EXTRACTOR

OK MACHINE & TOOL CORPORATION

3455 CONNER ST.,BRONX,N.Y. 10475 U.S.A.

PHONE 12121 991-6600 TELEX NO 125091

RINTED IN U.S.A.

PATENT PENDING

INS-1416

14-16 PIN DIP IC INSERTER

$ 3.49

MOS-1416

14-16 PIN MOS CMOS SAFE INSERTER

$ 7.95

MOS-2428

24-28 PIN MOS CMOS SAFE INSERTER

$ 7.95

MOS-40

36-40 PIN MOS CMOS SAFE INSERTER

$ 7.95

EX-1

14-16 PIN EXTRACTOR TOOL

$ 1.49

EX-2

24-40 PIN CMOS SAFE EXTRACTOR TOOL

$ 7.95

WK-7

COMPLETE IC INSERTER/EXTRACTOR KIT

$29.95

MINIMUM BILLING J25.00. ADD SHIPPING CHARGE $2.00. NEW VORK RESIDENTS ADD APPLICABLE TAX.

OK MACHINE & TOOL CORPORATION 3455 CONNER ST., BRONX, N.Y. 10475 (212) 994-6600/TELEX 125091

Circle 142 on inquiry card.

BYTE February 1981 207

Circle 143 on Inquiry card.

Model EP-2A-88

EPROM Programmer

Fast as Jackrabbits . . . Well, almost!

In Australia, two rabbits can reproduce over 13 million offspring in 3 years ... at 105 seconds for 2706's. the EP-2A-88 can reproduce 1,892,160 EPROMS in 3 yeai-s. Single push button control, the EP-2A-88 checks if EPROMS are erased, programs and verifies. It also checks for defective EPROMS.

Two basic models are available, The EP-2A-88-1 will accept Copy (CM) modules for the 2758, and 2716 EPROMS. The EP-2A-88-2 will accept copy modules for the 2716, 2732 and TMS 2532 EPROMS. Power requirements are 115 VAC 50/60 Hertz at 15 watts.

Pari No. Description Price

EP2A88 1 EPROM Programmer $490.00

EP 2A 88 2 EPROM Programmer 490.00

CM-50 Copy Module for 2716. TMS 2516 EPROMS 25.00

CM 70 Copy Module lor 2758 EPROMS 25 00

CM 20 Copy Module lor 2732 EPROMS 25 00

CM 40 Copy Module lor TMS 2532 EPROMS 25.00

Non Standard Voltage Option (220 v. 240 v. KXlu] 15 00

Optimal Technology, Inc.

Blue Wood 127, Earlysville, Virginia 22936 Phone (804) 973-5482

directly onto the screen, then the word PRINT, and put quotes in front and at the end of the graphics characters. When you hit enter, that line will be entered into BASIC as a new line. When you list the line, you will see the graphics characters printed as BASIC keywords, but when you execute the line, the graphics figure will be drawn on the screen. You can also set the drawings equal to strings (see figure 1).

Implementation Details

IRV can be purchased in 5-inch floppy disk or cassette form. The cassette version has instructions for saving the file to disk; disk-based users may want to do this, even though the program takes exactly 17 seconds to load from cassette. Different versions of IRV are loaded (from either cassette or disk) depending on whether your TRS-80 has 16 K, 32 K, or 48 K bytes of memory. All three programs are contained on either the disk or cassette versions of IRV. You must also answer the MEMORY SIZE? prompt when entering BASIC in order to allow sufficient space for the storage of IRV and its key redefinitions. This is simple to do and is explained in the IRV booklet supplied with the software.

IRV is available from several software suppliers, including The Programmer's Guild (POB 66, Peterborough NH 03458), The Software Exchange (6 South St, Milford NH 03055), and Scott Adams' Adventure International (POB 3435, Longwood FL 32750). IRV is sold with predefined keys (see table 1) and will operate in both Level II and disk BASIC. It is compatible with TRSDOS, NEWDOS, and OS-80. For those of you with newversion Level II ROMs (or read-only memories, which power up with the abbreviated message R/S L II BASIC instead of spelling out all the words), there is also a version of IRV that will operate on your keyboards: just specify that you have the new Level II ROMs.

Conclusions

• IRV is a versatile piece of utility software for the TRS-80 Model I BASIC programmer. It allows you to redefine any keystroke as any character or series of characters, and to modify BASIC programs by simply typing over a listing of the program.

• IRV can be used to renumber BASIC lines or to merge several lines or parts of lines without having to retype the lines involved. This is a valuable aid when modifying an existing program.

• IRV can be used to turn the cassette motor on and off without repeatedly plugging and unplugging the remote motor-control plug; this is a great help when trying to work with cassette tapes.

• IRV gives every key an auto-repeat facility.

[Editor's note: IRV is one of the most exciting pieces of software I've seen in a long time, primarily because it allows you to devise uses for it that are not specifically planned by the software designers. For example, when editing a line of BASIC code, you can use a single key that is defined as ten copies of the string "S D" (each of which will search for a blank and delete it) to take all of the spaces out of a line: this speeds up the task at hand by eliminating dozens of keystrokes. Because of its openended design, IRV can be used in a variety of situations, and I feel that it is as important and innovative as the popular VisiCalc program. Philip Mork, the author of IRV, is to be commended for his fine work.. .GW]|

208 February 1981 © BYTE Publications Inc

Circle 144 on inquiry card.

Now NRI takes you inside the

new TRS-80 Model III microcomputer

to train you at home as the

new breed off computer specialist!

NRI teams up with Radio Shack

advanced technolo y to teach

you how to use, program and

service state-of-the-art

microcomputers... It's no longer enough to be just a programmer or a technician. With microcomputers moving into the fabric of our lives (over 200,000 of the TRS-80™ alone have been sold), interdisciplinary skills are demanded. And NRI can prepare you with the first course of its kind, covering the complete world of the microcomputer. Learn At Home in Your Spare Time

With NRI training, the programmer gains practical knowledge of hardware, enabling him to design simpler, more effective programs. And, with advanced programming skills, the techni

Training Includes new TRS-80 Model III microcomputer, solid state volt-obm meter, digital frequency counter, and the NRI Discovery Lab with hundreds of tests and experiments.

(TRS-80 is a trademark of the Radio Shack division of landy Corp.)

cian can test and debug systems quickly and easily.

Only NRI gives you both kinds of training with the convenience of home study. No classroom pressures, no night school, no gasoline wasted. You learn at your convenience, at your own pace. Yet you're always backed by the NRI staff and your instructor, answering questions, giving you guidance, and available for special help if you need it.

You Get Your Own Computer to Learn On and Keep

NRI training is hands-on training, with practical experiments and demonstrations as the very foundation of your knowledge. You don't just program your computer, you introduce and correct faults.. .watch how circuits interact... interface with other systems... gain a real insight into its nature.

You also build test instruments and the NRI Discovery Lab, performing over 60 separate experiments in the process. You learn how your trouble-shooting tools work, and gain greater understanding of

the information they give you. Both microcomputer and equipment come as part of your training for you to use and keep. Send for Free Catalog... No Salesman Will Call

Get all the details on this exciting course in NRI's free, 100-page catalog. It shows all equipment, lesson outlines, and facts on other electronics courses such as Complete Communications with CB, TV and Audio, Digital Electronics, and more. Send today, no salesman will ever bother you. Keep up with the latest technology as you learn on the latest model of the world's most popular computer. If card has been used, write to:

NRI Schools

McGraw-Hill Continuing Education Center ■VSl'ii 3939 Wisconsin Avenue ■ ■nil Washington, D.C. 20016.

BYTE February 1981

209

Maximum Functions

Minimum Space

Maximum versatility

Minimum Price:

SYSTEM SUPPORT 1

If you ever need to crunch numbers, time i ntervals or events, create sequenced programs, check for power interruption, shuttle information through an RS-232C serial port at up to 19,200 Baud, tell your computer to do somethingat 02:47:37 AM on March 24th of 1982, employ 15 levels of interrupts, or need EPROM or battery-backup RAM to accomplish any of the above.. .and want to do all this while fully conforming to all IEEE 696/S-100 standards.. .System Support 1 is here.

Call (415) 562-0636,9 AM to5PMPST,for the name of a CompuPro retailer nearyou.

System Support 1 prices: $295 Unkit, S395 A/T, $495 qualified under the Certified System Component high-reliability program. Math processor and ROM/RAM optional at extra cost. Pricesshown do not include dealer installation and support services.

CompuPro™

^OAkRnTOrPOR^A94614

SQI

4513231 1789216 024867 579460

battery backup for onesocket

ELECTRONICS

210 BYTE February 1981

Circle 145 on inquiry card.

THE COMPUPRO SYSTEMS APPROACH:

Unlike "all-in-one" computers, CompuPro's modular S-100 systems HTP* TT POW^fTR

are amazingly flexible machines that are ideal for high level industrial 111U11 1 VTT J^JA,

commercial, and scientific applications. Full conformance to all IEEE TJTi° W P¥TT?17rf~IT?lVf A ATI"1!?

696/S-100 specifications ensures well integrated systems performance, XXXvfXX I MliMXF \JM\LVH\11 Vjt^

as well as freedom from obsolescence in the years to come. A rVTTk ITiriTT rrfTnATTniTnTTrr,

All CompuPro products meet the most demanding mechanical AIMD Xllljjl rUlOU (tH PI IT and electrical standards, accept the highest possible clock speeds for

maximum throughput and are backed with one of the best - if not the best - warranties in the business (1 year limited warranty on all products 2 year limited warranty for boards qualified under the Certified System Component program)

When you're looking for a computer, there are lots of choices. But when you need a precision machine that is built for the future as well as the present, the choice narrows down to the most experienced name in the S-100 business: CompuPro

NEW! COMPUTER ENCLOSURE 2

Introductory price: $795

Specify rack mount or desk top version.

We just made it easier for you to move up to an expandable S-100 system. . .COMPUTER ENCLOSURE 2 is ready to accept boards the minute it's unpacked. Heavy-duty, fused, constant voltage power supply provides +8 V at 25 Amps (I), + 16V at 3 Amps, and -16V at 3 Amps; 20 slot shielded motherboard, with active termination, offers high speed performance. Other features include dual AC outlets on rear, heavy-duty line filter, circuit breaker, quiet ventilation fan, reset switch, and black anodized front panel (with textured vinyl painted cover for desktop version). Rack mount version includes slides for easy pull-out from rack frame.

Also available: COMPUTER ENCLOSURE 1. Same as above, but less power supply and motherboard. $289 desktop, $329 rack mount.

LOWEST PRICE EVER ON

16K DYNAMIC RAMS - 8/$37

Just what you would expect from the memory leader: top quality, low power, high speed (200 ns) 16K dynamic RAMs, backed up with a 1 year limited warranty. Expand memory in TRS-80* -I and -II computers as well as machines made by Apple, Exidy, Heath H89, newer PETs, etc. Add $3 for two dip shunts plus TRS-80" conversion instructions. Limited quantity.

S-100 HIGH PERFORMANCE

MOTHERBOARDS

Actively terminated and fully shielded, these advanced motherboards handle the coming generation of 5 to 10 MHz CPUs as well as present day 2 and 4 MHz systems. Mechanically compatible with most computer enclosures. Unkits have edge connectors and termination resistors pre-soldered in place for easy assembly.

20 slot motherboard with edge connectors - Unkit $174, A/T $214 12 slot motherboard with edge connectors - Unkit $129, A/T $169 6 slot motherboard with edge connectors - Unkit $89, A/T $129

SOFTWARE

PASCAL/M* : $175 complete

PASCAL - easy to learn, easy to apply - can give a microcomputer with CP/M18 more power than many minis. We supply a totally standard Wirth PASCAL/M* 8" diskette and comprehensive manual. Specify Z-80* or 8080/8085 version.

8088/8086 MONITOR-DEBUGGER: $35

Supplied on single sided, single density, soft-sector 8" disc. CP/M* compatible. Great development tool; mnemonics used in debug conform as closely as possible to current CP/ M'" DDT mnemonics.

HIGH SPEED S-100 CPU BOARDS

8 BIT CPU Z

Like many others, we claim full conformance to IEEE 696/S-100 specifications; unlike many others, we'll send you the timing specs to prove it. CPU Z includes all standard Z-80A' features along with power on jump, on-board fully maskable interrupts for interrupt-driven systems, selectable automatic wait state insertion, provision for adding up to 8K of on-board EPROM, and 16/24 bit extended addressing. Works with 6 MHz CPUs; supplied with 4 MHz CPU. $225 Unkit, $295 A/T, $395 CSC.

16/8 BIT CPU 8085/88

When we shipped the first CPU 8085/88 board back in June of 1980, we created a bridge between the 8 bit world of the present and the 16 bit world of the future. By using an 8088 CPU (for 16 bit power with a standard 8 bit bus) in conjunction with an 8 bit 8085, CPU 8085/88 is downward compatible with 8080/8085 software, upward compatible with 8086/88 software (as well as Intel's coming P-Series), designed for professional-level high speed applications, and capable of accessing 16 megabytes of memory. . .while conforming fully to all IEEE 696/S-100 standards (timing specs available on request).

Looking for a powerful 8 bit CPU board? Looking for a powerful 16 bit CPU board? Then look at CPU 8085/88, the best of both worlds.

Prices: $295 Unkit, $425 A/T (both operate at 5 MHz); $525 CSC (with 5 MHz 80B5, 6 MHz 8088). Owner's manual available separately for $5.

8 BIT CPU 8085

This is a single 8 bit processor version of the above board, and may be easily upgraded to full 16 bit operation at a later date. $235 Unkit, $325 A/T, $425 CSC.

MPX 1: THE ANSWER TO COST-EFFECTIVE

MULTI-PROCESSING

MPX 1, a powerful front end processor/system multiplexer, unloads the host CPU to handle heavy 8 or 16 bit multi-user/multi-task traffic. This results in greatly increased throughput and speed of operation. MPX includes an on-board 5 MHz 8085 microprocessor, 2K of ROM, 4K or RAM, interrupt controller, and much more. Finally. . .multi-processing is an affordable reality. Call for pricing and delivery information.

OTHER S-100 BUS PRODUCTS

Active Terminator Board $34.50 Kit

Memory Manager Board $59 Unkit, $85 A/T, $100 CSC

Mullen Extender Board $59 Kit

Mullen Relay/Opto-lsolator Control Board . $129 Kit, $179 A/T

Spectrum color graphics board $299 Unkit, $399 A/T, $449 CSC

2708 EPROM Board (2708s not included) $85 Unkit, $135 A/T, $195 CSC

InterfaceM (dual RS-232 serial ports) $199 Unkit, $249 A/T, $324 CSC

Interfacer 2 (3 parallel + 1 serial port) $199 Unkit, $249 A/T, $324 CSC

S-100 MEMORIES FROM THE MEMORY LEADER

CompuPro memories feature fully static design to eliminate dynamic timing problems, full conformance to all IEEE 696/S-100 specifications, high speed operation (4/5 MHz Unkit, 10 MHz A/T and CSC), low power consumption, extensive bypassing, and careful thermal design.

Unkit

8KRAM2A $159

16K RAM 14 (extended addressing) $279

16K RAM 20-16 (extended addressing and bank select) $319

24K RAM 20-24 (extended addressing and bank select) $429

32K RAM 20-32 (extended addressing and bank select) $559

12BK RAM 21-128 (extended addressing) n/a

A/T

CSC

$189

$239

$349

$429

$399

$479

$539

$629

$699

$799

n/a

$2795

Most CompuPro products are available in Unkit form, Assembled/Tested, or qualified under the high-reliability Certified System Component (CSC) program (200 hour burn-in, extended 2 year warranty, more). Please note that unkits are not intended for novices, as de-bugging may be required due to problems such as IC inlant mortality. Factory service is available for Unkits at a flat service charge.

TERMS: Prices shown do not Include daalBT Installation and support servlcas. Cal res add tai. Allow al least 5% shipping: excess refunded. Orders under SIS add S2 handling. VISAS and Mastercard orders (S25 ffttfi) call (415) 562.0636, 24 hrs. Please include street address (or UPS delivery. Prices are subject to change without notice.

FREE CATALOG: Wanl more information? Then send lor our Iree catalog. For last 1st class delivery, add 41 cents in stamps; foreign orders add $2 (refundable with order).

'LEGAL CORNER. ZSOAisa registered trademark of Zilog; TRS-80 is a trademark of the Tandy Corporation: PASCAL'M is a trademark of Sorcim: CP'M is a registered trademark of Digital

COMPUPRO PRODUCTS ARE AVAILABLE AT FINER COMPUTER STORES WORLD-WIDE. . .

CALL (415) 562-0636 FOR THE STORE NEAREST YOU.

Circle 145 on inquiry card.

CompuProM

(BP@®00iJ

W^ ELECTRONICS ^

OAKLAND AiriHOHi, CA «46I4

ELECTRONICS (415)562-0636

BYTE February 1981 211

BYTELINES

News And Speculation About Personal Computing

Conducted by Sol Libes

U,

'NIX Standard Called For: "/usr/group" is a newly formed group for users of UNIX and UNIX-like operating systems. At a recent group meeting, a Western Electric representative disclosed that his company has granted approximately 156 commercial licenses at about 244 commercial sites. Many present at the meeting complained about Western Electric's excessive charges for unsupported software. The company typically charges $12,000 for a single processor license and as much as $40,000 for users of the DEC [Digital Equipment Corporation) VAX machines.

UNIX users, now faced with many different implementations of UNIX, are beginning to be concerned with standards. To help cope with the problem the group plans to issue a UNIX Users Cu/'de.

Also at the meeting, Microsoft announced plans for implementations of its Xenix package on the Texas Instruments TI9900, IBM Series/1, and Point 4 Data Corporation systems.

For more information write, /usr/group, POB 8570, Stanford CA 94305.

u

' CSD Pascal 4.0 To Be Released: A new version of UCSD Pascal will soon be released by Softech MicroSystems. The good news is that Pascal 4.0 will have many new features, such as multitasking and better screen handling. In other words, it will be more flexible, do more jobs, and be generally more powerful.

The bad news is that it will generate code that includes four new p-code instructions. Hence, the Pascal MicroEngine, presently the fastest available Pascal

system, will not be compatible with the new 4.0 version. Of course, WD (Western Digital) can recode the MicroEngine microcode ROMs (read-only memories) to include the new instructions, but I don't know. Considering that it took WD nearly a year to come out with the present ROM set, I do not foresee the possibility of MicroEngine Pascal 4.0 for some time yet.

Vo

olce Entry System For The Apple: Scott Instruments, Denton, Texas, will introduce an Apple version of its voice entry system. To be called "Applevet," this system will be able to recognize as many as 680 words or utterances. An $895 price tag for the system will include a plug-in board, a noise-canceling microphone, and demonstration disk.

Vo

olce-Operated Telephone Dialer Tested:

Bell Labs, Murray Hill, New Jersey, has disclosed that it is testing a telephone dialer that is voice operated. The caller can ask for a 4-digit telephone extension or a name in the directory of the system, and the system will then dial the number. The dialer has already demonstrated a high reliability. If in doubt as to what it is told, it asks the caller to repeat the entry.

The system uses a highspeed array processor attached to a minicomputer to detect the presence of speech and identify voice features to be used by a word recognizer. The word recognizer compares the features of the utterance to a subset of stored features

and generates a word-candidate list, which is ordered according to the probability of the word's occurrence. The system uses a feature template of the caller's voice, learned during a training period, to recognize the caller's voice input and dial the number. The system recognizes only isolated word inputs, and the user must speak slowly and haltingly.

w.

here Are The 64 K-BIt Memory ICs7

At one time, memory size quadrupled every two years. But four years have now elapsed between the introduction of the 16 K-bit and the 64 K-bit memory ICs. Skyrocketing development costs and difficulties in working with such dense devices have caused most of the delay. It is likely that the next quadrupling will take even longer.

Over two dozen suppliers are now delivering samples of 64 K-bit programmable memories to computer manufacturers; some of the samples are already in limited production. You can expect to see the first products using 64 K-bit integrated circuits in the third or fourth quarter of this year. However, do not look for their widespread use until sometime in late 1982 or 1983, when prices should drop to under $10 each.

American memory manufacturers are extremely concerned about Japanese competition in this area, however. The first company to supply 64 K-bit circuits was Fujitsu Ltd, and eight other Japanese manufacturers are jumping in too. Some manufacturers fear that the Japanese may snare 60% to 70% of the

64 K-bit memory market. If this occurs, the entire American computer industry may find itself in trouble.

^mpple Stock Goes On Sale: Shares in Apple Computer Inc, one of the most eagerly awaited public stock offerings, went on sale early in December 1980. Apple offered 8% of the company's 52.4 million shares (ie: 4.6 million shares) at a price of $22 per share.

Apple, incorporated in 1977, reported profits of $11.7 million on sales of $117 million for the fiscal year ending September 26, 1980. 1979's earnings were $5 million on $48 million sales, and, in 1978, sales were $7.8 million with profits of $793,497.

Steve Jobs, 25 years old, and Steve Wozniak, 30 years old, the creators of the Apple computer, each hold 8.3 million shares. That means that they own well over $100 million worth of stock. A C Markkula, 32 years old, who took Apple from a garage operation to its current enviable position, also holds 8.3 million shares. Venrock Associates, a venture capital firm, holds 3.8 million shares. Significant blocks are held by several other venture capital concerns. Xerox holds 80,000 shares.

ultatus Report On The IAPX-432: Late last spring, Intel announced its iPAX-432 32-bit microprocessor with great fanfare. At that time, only very general specifications were released and subsequently reported on in this column. (See "Intel Releases Data On 32-Bit Microproces

212 February 1981 © BYTE Publications Inc

zm

O

yg^

,VN^*S

aftflttO"

C^

OR^

[ttf>Y

,oP<>?8

^rs!*3&5*

>\G\^

«!

'++OS2*

09<0!°J

,«eW

,inon

J\W**.

,wo»*

fl\6t>v

..mo*9*'

«n8'

«n»

Q>|0»OU

««5'W°-ni«i*a',„,0l*<>8*8'

rtanu*

^25»<<

*«CT<w

««*«*

aor

WP

t**220&«0*

tllOO'

16^1

V,eN

»**?

Of***

• To*85.do^000:^*^^

SOW

tftf

for

rt\0»'

»tt*

«BI>»*

own*

.«»•

;RSOos,

0^o°s

«*2*fc*

«t*

ai«o\

oo^^ro^^0

jew tons

»«0.*»'

0(OO

cow**

*&&&£&****»

.11*. »395*

w

'pllW<**'

•8.»»S<

«P.S

BpiBWl"**

eon

^0,,<1,!i0oi«9SO!

wmW*8^

, Ptlce"

>PPL

„ « (8' sl"9

P»Cfc

l0o#8

^SBS^

JC^S

ftVtf

«SB

,»!

«10.

\oi

1W>

piod

■■^S^

1PS1.

SB

1*0"

• - w0.

•'<iV

flMOW

6501

imW'09.

*l5,0o*»«*W

1,6800

on»°lWtf

^8

^>,°'

tf»»

O?!*1*^ NCl

KC1

■ffSl'

SB

^pp^

ws*6':. m»« ^°?:» ,^»^ *B

.Wt?Bt50,,0

,100^9'

,u»8

•.tfSssS"

06M8»0'

,m«rt

. (^OMO^

•»^r

•«»-**iwS

„#,

»A30. »3»0. -»«50

Rei

iu\i2^

cwj*

ono

'SbpsS

U^ „i\\«

OOOB

COI

,mp«el

'SSS*

SSSSff ;;•■>-»

.-^^.«"

w CM*1" u

,„ nssemttW

»io.

'*b!5oW

ooti'

1US80

B0»w C6051

iiert*

CPl*

-aQ.

.»3»

w»

on**

ibo*

ve^07aoon\sW«r^(*P'0'

,*»•*"

,ne*

\ oW*

.«»■

»5?»

W*9„ 0 comfont

«***«! CO*68' „ foW

on*lWrtMSo'««"E

,(Wn»rt

slow

^*t'5>S!*«*«*

o»oo

O

COP'

s^s^

9W6' ,ft-»35

pioot rrusW9

o<5°*;

Cool0'

„Nseo'c,n<

,oi*

sssi

, oort0'

^•Ksass^-5*"

W'Toin*'

^JffiS*^.*-^*-*

^««^*N

*^£

pioceo'

foW

,oW9pl

,o\<*

poo'

*8*

5-0'1

n\o^'

8.SS,

Nff

SB

cp/»»

on*s

SCT?S,

w1

Honu^

aion»

»!*•

S^siotn eport

pie

(A*W9

40^ Tx.»580

del

,l\n»on

woo

, oo».

•<i*<?t^*«-,

soon

BOB*'

oom^rt'

-^JT^^^^'w*^:

-sSgiSSss5*

,u»Pw

OS

coW •HON

fleWs ■

pjiwoW

8,*8

(*P.SB

^

w-**.^.

§SS

to^r*^°ns

f'oo.^0L,e5swn

r^ssv-—*"'

Wcw»*?:.

CP/*08.

C8^W«

. »150

.»250. ,r80"»'*Wn

«odK>

^ppl

(,MP»*

,6ll>'om

3ffl)c

foflnds

.eciof

e«

SS (.W

,nnsw

Report Writer

trademark Carolina Business Computers

Selector IV trademark Micro-Ap Pearl trademark

ot CPU Int'l Pascal/M, ACT & TRANS 86 trademarks Sorcim

CBASIC2 trademark Compiler Systems Mogic Wand trademark Small

Business Applications Textwriter, Datebook & Milestone trademarks Organic Software

Ultrasort-ll & FABS trademarks Computer Control Systems Magic Menu trademark of Charles Merrirt

Copywriter, Copyproof & Diction trademarks Systronlcs Microstat trademark Ecosoft S-Basic trademark Topaz Programming

Spellguard trademark ISA CP/M_& MP/M trademarks Digital Research TRS-80 trademark Tandy Superbroin trademark Intertec Data

oov

^55w*»*

System's UCSD Pascal trademark of Regents of University of California WordStdr trademark Micro Pro Inn Spellbinder trademark Lexisoft For shipping add S5. In US; $10. outside US per package California residents add appropriate stale sales tax Terms: Prepaid check, M/C or VISA or In US COD (UPS) Dealer Inquiries Invited Prices quoted do not include dealer Installation & training Prices effective until April 1,1981

Circle 146 on Inquiry card.

BYTE February 1981

213

BYTELINES

sor," August 1980 BYTE, page 94.) During the fall, however, Intel made largescale presentations to several major systems-level houses. Rumor has it that Intel will deliver a paper at the International Solid State Circuit Conference (ISSCC) this month, in which it will divulge full details on the architectural design of the iAPX-32. Intel should start delivering samples within another month or two.

The iAPX-32 is a 3-chip set that uses more than 100,000 transistors per IC (all 64-pin packages). The design of the instruction set is aimed at supporting high-level compiled programs written in Pascal, Ada, and FORTRAN.

Intel had also let it be known that it planned to supply microcoded firmware in the processor device that would directly execute the Ada high-level language. However, rumor currently has it that Intel is retreating from this concept.

Status Report On 16-Blt M Icrocomputers:

The 16-bit scene matured during 1980. Intel sold about 200,000 of its 8086 devices (at well over $100 apiece, Intel appears already to be profiting from this unit). By midyear, Zilog had managed to remove the bugs from the Z8000 and, by year's end, was in full production. Motorola must be given credit for designing the most powerful 16-bit microprocessor (imagine having seventeen 32-bit-wide registers and 23-bit addressing to reach 16 megabytes of memory directly). It must be considered a landmark achievement that Motorola was actually shipping limited production quantities of fully functional 68000 devices by the end of 1980 that met specifications. This is particularly impressive when you consider the number of elements in the device (about 70,000) and the large size of the silicon chip (246 by 280 mils).

In production now for two years, the 8086 is just beginning to develop a respectable software base. For example, Digital Research is starting to supply an 8086 version of CP/M. The software bases for the Z8000 and 68000 are still extremely limited and are probably more than a year behind the 8086 software base.

National Semiconductor expects to start shipping samples of its new 16032 16-bit chip set, which promises features similar to the DEC (Digital Equipment Corporation) 32-bit VAX machines. The silicon area on this device (250 by 300 mils) is even larger than Motorola's 68000. Industry observers concede that this set of devices is significantly more powerful than the 68000, the Z8000, or the 8086. However, many observers doubt whether National will be able to compete with Intel, Zilog, and Motorola, because of its late start and the great expense of such a project.

■Soviets Develop

8080A-Llke Microprocessor: According to a technical report released by CDC (Control Data Corporation), the Soviet Union is manufacturing a microprocessor that is very similar to Intel's 8080A design. Control Data obtained samples of the integrated circuit from the Hungarian government, and promptly dissected it. They discovered that the device, called the K80IK8077, uses the same circuit blocks as the 8080A, except that it is adapted for the NMOS (n-channel metaloxide semiconductor) process.

In the manufacturing process, Soviet technicians relaxed line widths and geometry separations and used a larger chip size (214 by 192 mils, compared to 193 by 171 mils for Intel, which Intel later reduced to 165 by 161 mils). The Soviet design is thus more conser

vative and more expensive to produce. CDC identified several "workmanship flaws" in the devices (eg: questionable die attachments and scraping of bond wires). CDC felt that the Soviet technology was equal to American technology, vintage 1977. The device uses a 48-pin package with eight unused pins.

H

ome-Banklng/ Information System Inaugurated: Radio Shack, CompuServe, and United American Service Corporation have joined forces to inaugurate a nationwide home-banking and information system. (See "You Can Bank on It," January 1981 BYTE, page 10.) Using the new TRS-80 Color Computer, a television receiver, and a modem, a subscriber will be able to pay bills, obtain a bank statement, do bookkeeping, apply for a loan, send and receive electronic mail, and access the CompuServe data base. The service will cost between $15 and $25 a month. United American expects to have forty banks and 20,000 subscribers in the system by the end of the year.

■digital Research To Introduce Record-Retrieval System: Digital Research (DR) will soon introduce a record-keeping software package called BT-80. Basically, it is the kernel for a data-base management system. DR has also indicated that it is "taking a hard look at possibly implementing CP/M, MP/M, and PL/I on 68000 and Z8000 systems." Further, they have purchased a Digital Equipment Corporation VAX machine. Although this machine is primarily intended to keep track of their internal operations, it will be using the UNIX operating system. Does this mean that DR might be taking a close look

at UNIX? After all, several DR staffers have strong UNIX backgrounds.

Digital Research has also disclosed that it is considering the possibility of developing a software interface between CP/NET and the EtherNet systems.

I he Microprocessor Catch-22: Intel is currently the only supplier of the 8088 microprocessor (which is actually a 16-bit 8086 with 8-bit input and output). Most designers tend to avoid a part that is not "secondsourced." In other words, they want to be able to get the part from another source if their primary source has delivery problems. Mostek has said that it is interested in second-sourcing the 8088 if demand warrants. My question is, how is the demand to materialize while waiting for a second-source to enter the marketplace?

R

andom Bits And Random Rumors: The

EtherNet's specifications have been finalized and published. If you would like a copy, contactthe EtherNet Literature department at either Xerox, Intel, or Digital Equipment Corporation.... NEC is about to introduce a low-cost version of its Spinwriter word-processing printer. This new machine will sell for $1400 (in lots of 100) and it will also be used with a new NEC microcomputer system rumored for introduction later this year.... It is being whispered that Epson America Inc, Torrance, California, will soon unveil a low-cost daisy-wheel printer... Ontrax Corporation, Sunnyvale, California, plans to introduce a 116-megabyte 8-inch Winchester disk drive soon.... Before long, General Instrument will place on the market a speech-synthesis chip set in the $5 price range for large volumes. The set will include the controller, 32 K bytes or 128 K bytes of ROM and speech modules....

214 February 1981 © BYTE Publications Inc

DG: Realizing the H8's Potential

For the Engineer; Businessman; and Serious Hobbyist.

NEW! DG-64D5 Now Available

Uses Single 5 Volt Supply DYNAMIC RAMS. Like our DG-64D, asynchronous refresh maintains memory contents during extended wait states. Call for additional information.

Powerful, Bank Selectable 64K RAM

Our high capacity, low power DG-64D 64K RAM allows more efficient utilization of space, freeing your motherboard for peripheral interfacing.

Now 4MHz Operation

The DG-ADP4 allows for operation of the DG-80 CPU at 4MHz while maintaining compatibility with the H17 Disk System. Execution time of CPU intensive programs is reduced to half even before utilizing the enhanced Z80 instruction set.

Now Use Standard CP/M® Software

DG's system enhancements provide for RAM in Low Memory allowing the use of the widely accepted STANDARD CP/M.

Now Operation in Powerful Z80®Code

Our DG-80 Z80R based CPU opens a new world of more powerful AND efficient languages and software.

Increased Flexibility With New Monitor

DG's FP8 monitor allows front panel debugging of 8080 AND Z80 machine language programs in either hexadecimal or octal format. Maintains all PAM-8R entry points ancTfeatures. All register sets available.

The DG system enhancements for the Heath H8 computer are definitely a step above in price, performance, and factory support.

THE DG-80 ZILOG Z80®BASED CPU — $249.00 (Documentation Only $25.00)

FEATURES:

• Compatible with Heath* H8 hardware and software

• Z80CPU— Enhanced instruction set • Provisions for up to 8KR0M/EPR0M and/or 4K RAM • Jump-On-Reset to any 1K boundary • DIP switch selectable wait

states for any or all 8K blocks of memory • All Z80 interrupt response modes available • Interrupt Acknowledge and Dynamic Memory Refresh signals available on bus • Frequently selected options by DIP switch or solderless jumper • Machined contact gold sockets for

R0M/EPR0M. RAM • Includes many advanced features for future expansion • Assembled, tested and guaranteed • Extensive operations manual and Z80 PROGRAMMING MANUAL

90 DAY WARRANTY

DG-64D BEST RAM EVER AVAILABLE FOR

THE H8.

NEW! 5 VOLT ONLY VERSION 64K RAM —DG-64D5

Uses Single Supply 5 Volt Dynamic RAMS. Call for further information. FEATURES:

• Up to 64K bytes capacity Dynamic RAM

• Hardware bank selectable in 8K increments • Software bank selectable in 16K increments through I/O port • On-board bank select/CPU ROM disable port, address

able to any of 256 I/O addresses • Up to 8 boards controllable through one I/O port (allows page mode operation) • On-board transparent refresh for 8080 or Z80 microprocessor backed up by asynchronous

refresh which maintains memory contents during extended wait states • 4 MHz operation with no wait states required • Low power consumption—less than 8 watts • Assembled, tested, & burned-in • 90 DAY WARRANTY • 64K-S529.00; 48K$480.00; 32K-S431.00; 16K-S382.00; 0K-S333.OO; Documentation 0nly-$15.00

DG-FP8 — $69.95

Monitor/Utility package for DG-80 CPU provides functions of PAM-8 as well as the following:

• Split Octal or Hexidecimal Entry and Display • Z80 monitor features such as display alternate register sets, display index registers, • "Shorthand" display of memory contents pointed to by general purpose Documentation Only - $15.00 (Source Listing Not Included)

registers • Supports STANDARD CP/M provided by D-G as well as HDOS • Provides firmware support for DG-ADP4,4 MHz hardware • Includes single step features

DG-ADP4 — $19.95

Plug-in hardware modification to allow operation of the Heath" H17 disk system with the DG-80at4 MHz. Requires the use of the DG-FP8 firmware package.

16K CHIP SETS $49.00

(8-4116 Type Dynamic RAMS) for DG-32O.0G-64O,Apple".TRS-80" H88/89".andPef

DG-CMD1 — $29.95

ROM disable port for use with the Heath* H8 computer. Addressable to any of 256 I/O ports. Allows the use of a full 64K of RAM when used in conjunc

tion with the DG-80 CPU and the DG-FP8 hardware/firmware package (NOT REQUI RED FOR SYSTEMS UTILIZING THE DG-64D MEMORY BOARD)

DG-FP8/DG-ADP4 - TOGETHER - $79.95

Save on Combination Purchase — Reg. $89.90

DG-32D — 32K — $339.00 — 16K — $287.00 —tfK — $235.00-DOCUMENTATION $12.00

STANDARD CP/M Ver 2.2 $130.00

CP/M is a registered trademark of Digital Research of Pacific Grove. California. Heath. HDOS. H 8, H88/89 & PAM8 are registered trademarks ofthe Heath Company, Z80isa registered trademark of Zilog Corp. PET is a registered trademark of Commodore. Apple is a registered trademark of Apple Computer TRS-80 is a registered trademark of TANDY Corp,

n-B

Ordering Information: Products listed available from DG Electronic Developments Co., P.O. Box 1124,1827 South Armstron, Denison, Tx. 75020. Check, Money Order, VISA or Master Charge accepted Phone orders (charge only) call (214) 465-7805. No COO's. Freight prepaid. Allow 3 weeks for personal checks to clear. Texas residents add 5%. Foreign orders add 30%. Prices subject to change without notice.

Circle 147 on inquiry card.

BYTE February 1981

215

BYTELINES __

Hewlett-Packard is about to set forth a single-board microprocessor version of its 1000-L computer to compete with the Digital Equipment Corporation LSI-11.... Control Data plans to introduce a self-contained PLATO system. The PLATO system is currently a mainframe-based system that includes remote terminals with high-resolution graphics and an extensive library of interactive educational software... Shugart Associates, the current leader in floppy-disk drives, is rumored to be developing an optical diskstorage system. The basic technology for this system was developed by Shugart's parent organization, Xerox, and Thompson-CSF...,

■ Irst Xenlx/Z8001 System Announced: Tri

Data Systems, City of Industry, California, is the first company to announce a microcomputer system using the Zilog Z8001 and Microsoft's Xenix operating system. The Z8001 employs segmented rather than direct addressing. This desk-top system, called the SST, contains a Z8010 memory-management integrated circuit that dynamically relocates

code and protects memory areas. The SST utilizes a tenslot motherboard for memory expansion in 128K-byte modules.

w,

III Microcomputers Leapfrog Over Minicomputers and Mainframes?

The newer 16- and 32-bit microprocessors, soon to be sampled by integratedcircuit manufacturers, will contain some new and sophisticated features. For example, the forthcoming NS16000' 16-bit microprocessor from National Semiconductor and the iAPX-432 microcomputer from Intel will both have true virtual memory capability that will allow very large memory systems. Sixteen-bit microcomputers like the 8086, Z8000, and 68000 do not lend themselves to virtual memory systems. Intel, however, says that it expects to have an 8086 with virtual memory later this year.

Virtual memory requires the microprocessor to stop in the middle of an instruction if it determines that the address called is not in memory, back up execution of the instruction, and restart the instruction after the contents of that virtual address have been brought in from a

mass-storage device (eg: a hard disk).

Returning to the original question, experts concede that, simply because microcomputers now have features once found only in larger machines, it does not follow that they will overtake minicomputers and maxicomputers. Each year the minicomputers and maxicomputers add performance features that keep their power far ahead of microcomputers. In fact, the new more powerful microcomputers now have features that were found in larger systems five or more years ago.

R,

,obot Kit Announced: In the December 1979 BYTE News, I predicted that a robot kit would be introduced in 1980. It now seems as if that prediction will come true in 1982. Heath Company recently demonstrated a 3-foot-high robot prototype to Heath retailers that it plans to introduce in 1982. The robot kit will use the Motorola 6802 microprocessor with 4 K bytes of programmable memory and 32 K bytes of ROM (read-only memory). It will have a detachable

joystick, voice synthesis, and one multipurpose arm. At this time, it is projected that the kit will cost less than $1000.

Whange Of Name:

Seagate Technology is the new name for Shugart Technology. Seagate Technology is the Scotts Valley, California, firm that manufactures Winchester-technology 5'/-inch hard-disk drives. The decision to change its name was made by Seagate Technology to help distinguish it from the famous maker of floppy-disk drives, Shugart Associates. Both companies were founded by David Shugart. However, Mr Shugart is no longer affiliated with Shugart Associates.

MAIL: I receive a large number of letters each month as a result of this column. If you wish a response, please include a stamped, self-addressed envelope.

Sol Libes POB 1992 Mountainside NJ 07092

LET YOUR APPLE SEE THE WORLD!

The DS-65 Diglsector" is a random access video digitizer which converts a TV camera's output Into digital Information the Apple can process. It features 256 X 256 resolution with up to 64 levels of grey scale Scanning sequences are user programmable. On-board software in EPROM is provided for displaying digitized Images on the Hi-Res screen.

Use the DS-65 for: Precision Security Systems • Computer Portraiture • Robotics • Fast to Slow Scan Conversion • Moving Target Indicators • Reading UPC codes, schematics, musi cal scores and paper tape •

THft&D®D^§>

DS-65 Price: $349.95 FSII Camera Price: $299.00 Combination Price: $599.00

NEW SOFTWARE FOR THE DS-65 IS NOW AVAILABLE ON DISK!

— Portrait System Software:This program includes captions and a credit line, reverse printing for T-shirt application and the option to save portraits on disk.

— Picture Scanner: Provides a variety of different dithering algorythms for compressing the digitized Image into the Hi-Res screen.

Write or call for more Information!

GIVE YOUR APPLE THE GIFT OF SIGHT!

Master Charge / Visa Accepted

M® [SUSS3 RO. BOX 1110 DEL MAR, CA 92014 714-942-2400

216 February 1981 © BYTE Publications Inc

Circle 148 on inquiry card.

This

printer

costs less

than $450.

Beat that...

if you can.

Epson

This is the Epson MX-70. The lowest priced dot matrix printer you can buy. Now, that in itself should make it very attractive to a lot of people. But you ain't heard the half of it.

To begin with, the MX-70 has a lot more in common with our now-famous MX-80 than just the name. Like unequalled Epson reliability. And technological breakthroughs like the world's first disposable print head. But frankly, the MX-80 packs a lot more power than some people need. So we built the MX-70 to be a no-frills printer. At a no-frills price.

But the MX-70 is still a great little printer. We give you 80CPS unidirectional printing. Top-of-form recognition. Programmable line feed and form lengths. Plain paper printing. An easy-to-read 5x7 matrix. Self test. And an adjustable tractor feed.

That's what you'd expect

from a basic little printer. But here's something you wouldn't expect: the finest graphics package on the market today. Free.

We call it GRAFTR AX II. And it means 480 dots across the page, resolution to 60 dots per inch, and a graphic image free of the jitter and overlap that plagues other printers. You get cleaner grays and finer point resolution.

So now you've got a choice. You want more power and extra functions, you buy the MX-80. You want a basic little printer that prints, and keeps on printing, you buy the MX-70. They're both at your dealer now.

But at this price, you'd better hurry.

EPSON

EPSON AMERICA, INC.

23844 Hawthorne Boulevard • Torrance, California 90505- (213) 378-2220

Circle 149 on Inquiry card.

BYTE February 1981

217

H

CQMPuTTRQNICS

N C.

... EVERYTHING FOR YOUR TRS-80 •••

* TRS-80" is a trademark of the Radio Shack Division of Tandy Corporation

****** >*-***

MOD-II PROGRAMS

* All orders processed within 24-Hours •k 30-Day money back guarantee on all TRSDOS Software •k Add $2.00 for shipping in UPS Areas • Add $3.00 for C.O.D. or NON-UPS Areas • Add $4.00 outside U.S.A., Canada & Mexico •k We will match any bonafide advertised price in any of the Major Computer Magazines

A

L L

S 0

F T W A R E

LISTED HERE

"w o

R K S

W I

T H

T R S D 0 S*

(1) ELECTRIC PENCIL (Michael Shrayer Software)... Complete word processor with extensive editing and

printer tormatting features $325 (STANDARD

TRSDOS VERSION)...$350 (DIABLO, NEC OR QUME TRSDOS VERSION).

(2) GENERAL LEDGER, ACCOUNTS RECEIVABLE, ACCOUNTS PAYABLE, INVENTORY CONTROL, INVOICING AND PAYROLL (Small BusinessSystems Group) ...an extensive businesssystem for the serious user...can be used one module at a time or as a coordinated system...$225. per module...$1299 for the complete system.

(3) GENERAL LEDGER, ACCOUNTS RECEIVABLE, ACCOUNTS PAYABLE, INVENTORY CONTROL AND PAYROLL (Compumax) ...a complete user oriented business system ...can be used one module at a time or as a coordinated system... $140 per module... $995 for the complete system.

(4) MOD-II UTILITY PACKAGE (Racet Computes)... adds important utilities to TRSDOS...copy files selectively...faster and more accurate file copying... repair bad directories...displays sorted directory of all files on 1 to 4 disk drives...SUPERZAP...change disk IO...and more...$150.

(5) ADVENTURE #1-#9 (Scott Adams - Adventure International)...a series of games formally only available on the large computers...your goal is to work your way through a maze of obstacles in order to recover a secret treasure or complete a mission...the package includes all 9 Adventures written by Scott Adams.. $99.95.

(6) GSF (Racet Computers)...Generalized Subroutine Facility...a series of super fast machine language utilities that can be called from a BASIC program (no machine language knowledge required)...sorts 1000 items in under 5 seconds...allows PEEK and POKE statements...move data blocks...compress and uncompress data., works under TRSDOS.. $50.

(7) DSM (Racet Computes)... Disk Sort Merge ..sorts and merges large multiple diskette files on a 1 to 4 drive system...NOT AN IN MEMORY SORT ...can actually alphabetize (or any other type of sort) 4 disk drives worth of data., sorts one complete disk of information in 10 minutes...information is provided to use DSM with the RS MAILING PROGRAM ...works under TRSDOS...$150.

(8) RSM (Small Systems Software)...a machine language monitor and disassembler...can be used to see and modify memory or disk sectors...contains all the commands found on the Model-I version plus some additional commands for the MOD-II...works under TRSDOS...$39.95.

(9) BLINK BASIC LINK FACILITY (Racet Computes).. Link from one BASIC program to another saving all variables...chain programs without losing variables ...$50.

(10) BASIC CROSS REFERENCE UTILITY (Racet Computes)., lists all variables and strings used in a program (with the line numbers in which they appear) ...lists all GOTO's and GOSUB's (with the line numbers in which they appear) ..searches for any specific variables or strings (with the line number in which they appear) ..$50

(11) DEVELOPMENT PACKAGE (Racet Computes)... SUPERZAP (to see, print or change any byte on a diskette)...Disassembler and MOD-II interface to the

MICROSOFT EDITOR ASSEMBLER PLUS including uploading services and patches for Disk I/O..assemble directly into memory...save all or portions of source to disk., dynamic debug facility (ZBUG)...entended editor commands...$125.

(12) HARD/SOFT DISK SYSTEM (Racet Computes)... The software essential to inte face any of the popular large hard disk drives...completely compatible with your existing software and files...allows up to 20 megabytes ofstorage (and larger)...directory expandable to handle thousands of files...$400.

(13) CAMEO HARD DISK DRIVE CONTROLLER coming soon (November 1?)

(14) HARD DISK DRIVES...coming soon (Nov. 1?).

(15) HIE COMPUTRONICS, INC. SHARE-APROGRAM DISKETTE #1...works under TRSDOS...a collection of programs written by MOD-II owners.. programs include data base management...a word processor.mail system ...mortgage calculations... checkbook register...and many others...$8 (add $3 postage outside of the United States, Canada and Mexico)...FREE if you send us a diskette containing a program that can be added to the SHARE-A-PROGRAM DISKETTE.

(16) WABASH CERTIFIED DISKETTES ..$39.95 (per box of 10).

(17) FLIP SORT DISKETTE STORAGE TRAY ..Stores 50 diskettes, .comes complete with index-dividers, tilt plates and adjustable spacing...$44.95.

(18) MASTER PAC 100...100 essential programs. . BUSINESS...PERSONAL FINANCE ..STATISTICS... MATH...GAMBLING...GAMES...includes 125 page manual and 2 diskettes...$99.95.

(19) BUSINESS PAC 100... 100 essential business programs...INVENTORY CONTROL. PAYROLLBOOKKEEPING SYSTEM...STOCK CALCULATIONS...CHECKBOOK MAINTENANCE...ACCOUNTS RECEIVABLE-ACCOUNTS PAYABLE... includes 125 pagemanualancltwodiskettes...$149.95.

(20) EDITOR ASSEMBLER (Galactic Software Ltd.).., the first user oriented Editor Assembler for the MODEL II and was designed to utilize all the features of the MODEL II It includes innovative features for ease of coding and debugging and complete documentation (over 120 pages)...works under TRSDOS ...$229.00.

(21) BASIC COMPILER (Microsoft)...changes your source programs into machine language ...increases program execution by 3-10 times...$395.

(22) MAIL/FILE SYSTEM from Galactic Software Ltd. stores 2,500 names per disk. No sorting time is required since the file is automatically sorted by first and last name plus Zip Code on input. Retrieve byany combination of 19 user codes Supports an 11 digit alphanumerica Zip. Supports a message line. Comes complete with user-oriented documentation (100page manual). Allows for company name and individual of a company and complete phone number (and extension), works under TRSDOS. .$199.00

(23) INCOME TAX PAC...Professional income tax package...most forms and schedules ..output to video or line printer..automatic memory storage of all information...data can be loaded from diskette, changed and edited ...built in error checking . $199.95.

(24) COMPUTER GAMES (SBSG)...Mean Checker Machine, Star-Trek III, Concentration, Treasure Hunt. Banco, Dog Star Adventure...$74.95.

ICQMPJTRQNICS!

50 N. PASCACK ROAD SPRING VALLEY, NEW YORK 10977

r^m\ _ _ hour

\S8*i24 ORDER \-~~~^~" LINE

(914) 425-1535

218 BYTE February 1981

NEW TOLL-FREE

ORDER LINE

(OUTSIDE OF N.Y. STATE)

(800) 431-2818

[

(1) CP/M (Lifeboat Associates) an alternative

operating system for the MOD-II that allows MOD-II owners to use any of the hundreds of programs available under CP/M...$170.

(2) CP/M HANDBOOK (Sybex) a step-by-step guide to CP/M...takes the reader through each of the CP/M commands...numberous sample programs... practical hints.reference tables...$13.95.

(3) GENERAL LEDGER, ACCOUNTS RECEIVABLE, ACCOUNTS PAYABLE, INVENTORY CONTROL,

AND PAYROLL (Peachtree Software)., requires CP/M and MICROSOFT BASIC...professional business systems...turn key operation ...can be used as single modules or as a coordinated system...$500 per module...$2500 for the complete system.

(4) WORD-STAR...The ultimate word processor ..a menu driven word processing system that can be used with any printer. All standard word processing commands are included ...plus many unique commands only found on WORD STAR...requires CP/M ...$495.

(5) MAIL LIST MERGE ...An add on package that allows the user to send form letters (created on

I WORD-STAR) to any compiled mailing list (using any CP/M based MAIL program such as the PEACHTREE MAIL PROGRAM)..requiresCP/M, WORDSTAR and andy CP/M based mail program...$150

(6) SELECTOR 111 (Micro-Ap) ...complete data management system...userdefined fields and codes... manages any list defined by the user., includes additional modules for simplified inventory control, accounts receivable and accounts payable...requires

I CBASIC-2...S295.

(7) SELECTOR IV (Micro-Ap)...the ultimate data management system...all features use the SELECTOR III plus...data file format conversions., full page report formatter...computations..global search and replace ...hard disk compatible., data/text merging...$550

(8) GLECTOR (Micro-Ap).. add on package to the SELECTOR., general ledger that allows the user to define a customized chart of accounts . $350.

(9) C8ASIC-2 a non-intesactive BASIC used for many programs that run under CP/M...allows user to make more efficient use of disk files...eliminates the use of most line number references...require on such programs as the SELECTOR...$120,

(10) MICROSOFT BASIC...an enhanced version of the MICROSOFT BASIC found on TRSDOS ...adds commands such as chaining (allows the user to LOAD and RUN a new program without losing the variables currently in memory), .long variable length file records. WHILE/WEND and others...can be used with the BASIC COMPILER to speed up programs (3-10 times faster execution)...$325.

(11) MASTER TAX (CPAids) ...professional tax preparation program., prepares schedules, A. B. C. D, E, F, G, R/RP. SE. TC. ES and forms 2106. 2119. 2210. 3468, 3903. 2441. 4625, 4726. 4797. 4972. 5695 and 6521. Printing can be on readily available pre-printed continuous forms, on overlays, or on computer generated IRS approved forms. Maintains dint history files...interactive with CP/Aic!s General Ledger...$995.

(12) GENERAL LEDGER II (CPAids) ...designed for CPA's...stores complete 12 month detailed history of transactions...generates financial statements, depreciation, loan amortizations, journals, trial balances, statements of changes in financial position, and compilation letters...includespayrollsystemwith automating posting to general ledgers...prints payroll register, W2"s and payroll checks..$450.

(13) ELECTRIC PENCIL (Michael Shrayer Software) ...Complete word processor with extensive editing and printer formatting features...$275 (Standard printer version)...$300 (DIABLO. NEC or QUME version).

(14) BASIC COMPILER (Microsoft) .changes your source programs into machine language...increases program execution by 3-10 times...5395.

(CP/M IS A REGISTERED TRADEMARK OF DIGITAL RESEARCH)

A

L L

P R O G R A M S

R

E

Q

U

I

R

E

C P

/ M*

NEW!!!

MOD-II NEWSLETTER $H/year Cor VX issues)

Circle 150 on inquiry card.

THE ORIGINAL MAGAZINE FOR OWNERS OF THE TRS-80™* MICROCOMPUTER

SOFTWARE

FOR TRS-80'"

OWNERS

H

CQMPJTRQMCS

I

N C.

MONTHLY

NEWSMAGAZINE

FOR TRS-80 "

OWNERS

MONTHLY NEWSMAGAZINE

Practical Support For Model I, II & III

PRACTICAL APPLICATIONS BUSINESS

GAMBLING • GAMES EDUCATION PERSONAL FINANCE BEGINNER'S CORNER NEW PRODUCTS SOFTWARE EXCHANGE MARKET PLACE QUESTIONS AND ANSWERS PROGRAM PRINTOUTS AND MORE

FREE*

PROGRAMS AND ARTICLES PUBLISHED IN OUR FIRST 12 ISSUES INCLUDE THE FOLLOWING:

A COMPLETE INCOME TAX PROGRAM (LONG AND SHORT FORM)

INVENTORY CONTROL

STOCK MARKET ANALYSIS

WORD PROCESSING PROGRAM (FOR DISK OR CASSETTE)

LOWER CASE MODIFICATION FOR YOUR VIDEO MONITOR OR PRINTER

PAYROLL (FEDERAL TAX WITHHOLDING PROGRAM)

EXTEND 16 DIGIT ACCURACY TO TRS-80'" FUNCTIONS (SUCH AS

SQUARE ROOTS AND TRIGONOMETRIC FUNCTIONS)

NEW DISK DRIVES FOR YOUR TRS-80'"

PRINTER OPTIONS AVAILABLE FOR YOUR TRS-80'"

A HORSE SELECTION SYSTEM***ARITHMETIC TEACHER

COMPLETE MAILING LIST PROGRAMS [BOTH FOR DISK OR CASSETTE

SEQUENTIAL AND RANDOM ACCESS)

RANDOM SAMPLING***BAR GRAPH

CHECKBOOK MAINTENANCE PROGRAM

LEVEL II UPDATES***LEVEL II INDEX

CREDIT CARD INFORMATION STORAGE FILE

BEGINNER'S GUIDE TO MACHINE LANGUAGE AND ASSEMBLY

LANGUAGE

LINE RENUMBERING

AND CASSETTE TIPS. PROGRAM HINTS. LATEST PRODUCTS

COMING SOON (GENERAL LEDGER. ACCOUNTS PAYABLE AND

RECEIVABLE. FORTRAN 80. FINANCIAL APPLICATIONS PACKAGE.

PROGRAMS FOR HOMEOWNERS. MERGE TWO PROGRAMS.

STATISTICAL AND MATHEMATICAL PROGRAMS (BOTH

ELEMENTARY AND ADVANCED) . . AND

Or

' IKS,si)" IS A rWAI'KMAKIWORD PROCESSING PROGRAM For writing letters, text, mailing lists, etc.. with each new subscriptions or renewal LEVEL II RAM TEST Checks random access memory to ensure that all memory locations are working properly DATA MANAGEMENT SYSTEM Complete file management for your TRS-80'". CLEANUP Fast action Maze Game.

ADVENTURE Adventure #0 by Scott Adams (From Adventureland International). * All programs are supplied on cassette (add $3 for Diskette Version - add $5 for modified Mod-II Version).

1)1 I AM IV I OKI'

**££

SEND FOR OUR NEW 48 PAGE SOFTWARE CATALOG (INCLUDING LISTINGS OF HUNDREDS OF TRS-80'" PROGRAMS AVAILABLE ON CASSETTE AND DISKETTE). $2.00 OR FREE WITH EACH SUBSCRIPTIONS OR SAMPLE ISSUE.

CQMPUTRQNICS

50 N. PASCACK ROAD SPRING VALLEY, NEW YORK 10977

ONE YEAR SUBSCRIPTION $24 TWO YEAR SUBSCRIPTION $48 SAMPLE OF LATEST ISSUE $4

HOUR

ORDER

LINE

(914) 425-1535

NEW TOLL-FREE

ORDER LINE

(OUTSIDE OF N.Y. STATE)

(800) 431-2818

START MY SUBSCRIPTION WITH ISSUE

(»1 - July 1978 • S7 - January 1979 • 812 - June 1979 < NEW SUBSCRIPTION RENEWAL

#18 - January 1980)

CREDIT CARD NUMBER

SIGNATURE

NAME

EXP. DATE,

ADDRESS.

-CITY

STATE.

-ZIP

ADD $6 YEAR (CANADA. MEXICO) . ADD $12 YEAR AIR MAIL ■ OUTSIDE OF USA. CANADA & MEXICO *"

Circle 150 on inquiry card.

BYTE February 1981 219

Image Processing With a Printer

Clark A Calkins 2564 Walnut Blvd #106 Walnut Creek CA 94598

For a long time I have been interested in producing recognizable images using a basic Teletype just as you see in many computer stores; and I thought that an expensive camera and interface were required to digitize the picture. But in 1979 an article in Dr Dobb's Journal described just how to do this type of image processing with a Diablo printer. (See reference 1.) While I didn't have this type of printer, I figured the concept should work with my Model 43 Teletype or any other printer. After all, the hardware interface required looked simple enough. What could I lose? I worked out my ideas, implemented the system, and now I can process images inexpensively at home. So as a successful personal-computer experimenter, I'll pass on my experience to you.

An Overview of the System

The principle behind this image processing system is easy to understand and implement in a home computer system. The procedure used to

About the Author

Clark A Calkins has worked for 11 years with the General Electric Company at the Vallecitos Nuclear Research Center and now holds a position as a systems programmer for the Advanced Nuclear Applications Group.

prepare a digital picture contains the following steps:

• Connect a light-sensitive device (such as a phototransistor) to the input of an A/D (analog-to-digital) converter that is connected to the computer.

• Mount the phototransistor on the print head of the printer so that it senses light reflected off the paper in the printer's print position.

• Place the paper containing the image in the printer so the print head will traverse the image; then send a series of space characters to the printer to cause the print head to move across the paper.

• Measure and store the values of light intensity at each character position under program control, using A/D-converter output.

• Insert a blank sheet of paper into the printer.

• Use a computer program to print selected characters onto the blank sheet; each character corresponds to the light intensity at a given print position. The higher the intensity, the lighter the character should be.

Having decided that this would be an interesting project, I went to the local electronics store and purchased the necessary parts and assembled the unit. When I loaded in a sample control program written in BASIC, the

thing actually worked, and after a little experimentation, I could even recognize some features! Then the fun started, I cut pictures from the magazines lying around the house and started to process them while trying different substitution characters. This was great fun for my entire family!

After a few hours of playing with this system, I started to realize that I needed a better control program that would execute faster. The BASIC program worked at about three characters per second, but with a faster program, I could try larger pictures. The basic functions required were:

• Scan over a variable-width image of any reasonable length at a much faster speed.

• Save the resulting digital data out on a disk file for later use.

• Be able to use a user-defined character-substitution sequence (the more flexible, the better).

The results of this effort are shown in listing 1. Here is a control program written for the CP/M (version 1.4) operating system that does what is required (and a little more). It can scan a line of up to 255 characters and as many as 255 lines (memory permitting). The character-substitution sequence is limited to sixty-four char

220 February 1981 © BYTE Publications Inc

o ro vj m

U M M M

i—i i—i ro ro ro oj ro o oo r*B :

c*jc*ji—'roHHt—trorjrororowo

»—1»—iWMfoww^OD*

ro i—i ro ro ro

coji-Ht—i w i-i ro ro ro i-h

u u u

ro o ■**»■

u u z

04 V* SB

OJ CO 4*

2! Mh Z U M

z ro h

1—1 ro ro ro ro ro

wio\jMW\iHWHro wrosjHMHWWHWfo

u u h # h m >-1 f-i ro f» 0*1 _ roroi—i+r +ri—tNjxjrororoWM

ron# \i \i \j 1-• .—» t—< ro oj ■»*

■nj »—1 »-H o at

nj 1—1 ro o a»

1—* »-< i-h ro 00 a*

h m ro z a

H H H o it *

■—* ro ro oj m m

M \J H M 4^ « •

•-. _ ►_1 00 «i a«

NJ H N} CD « « + + +r +r i^NJ\JMtt»«

* + + NJ\JttMMWM»«

* * +r + #sJMHO*«« + + + +r *- Nj 1—. .—1 U « « »

*•■ + + *\j+r»-trooa»«»ar»

-4- +fr # 4- #H\JhCO««*

+ + + ■* #NWWCO»»«

+r * + <t-NNrouz«««

+ + + + #HHM*«««

+ —. —- -w -H-xjroow****

* ■+■ ■+- +NJHHU*«««

ro ro ro ro ro ro

OWN)

** ro i-i

ro i-h

n-i ro

•-• nj

1—1 ro

NJ l-l

1—1 *—*

1—1 ro

NJ f-t

ro 1—t

■VI

+

NJ

"■J

NJ

-0

+r

+r

NJ

NJ

+f

■M

NJ

•M

t—1

•VI

+

-O

1—1

NJ

w

VI

w

NJ

1—4

+

+r

NJ

NJ

1—1

*r

+

+r

1—1

NJ

+

+f

+r

*

»—1

■M

+

"VJ

NJ

NJ

ro w m ro

ro ro Nl ro ro 1-1 Nl ro Nl ro vj t-t

* ro i-i 1—1

vj l-l

* ro

■ ••^UHHMNJ

• * 00 •• h a r» m go w a* ►-• rm

M at O at •* M *•

* * O 0OM *M M at O O M M M

CO

CD >-"

M ro

■» o

a* 00

vj 1-1

MM VJ

ro ro

ro .-1

o l-l

M CO

at at co o vj +. o ro vj vj vj « —» —

NJ U « «

+ vj m ro

CO l-l

VJ 00 — vj

W M - I

1-1 + — I

at © Nl ^

+ nj ro ro

— + * * ft oj 00 + -v +f vj i-h ro ae

+ vj ro ro

vj v^ ,_, w

+ ft t—t ro

+r +r rO Ul

vj 1-1 i-i o

+ vj ro ro

1» CO

at O

at * w M ^ n 1

00 o ro 1—1 + v. 1

o >-i + ro vj + —

• ••0O ONJ

CO OJ CO o

•>- • MM W«

+ + + vj ro ro at

^v + vj vj 1-1 oJ

vj vj vj + — I

^ V I I

vj >_| vj I-I l-l vj

* l-l

vj vj l-l VJ

# l-l

l-l vj

VJ l-l

VJ ft

ft vj

ro i—t 1-1 ro

OJ l-l OJ 1-1

ro 1—1

O vj O l-l O 1-1 0O vj «► 1-1

00 1—1 CO l-l

co ro

at 1-1 00 I—I

00 ro as vj

~. * 1—1 1—1 ro a*

» vj ro ro

co oo co co

» W M M \J ^. I

o u ro ro h #

~v + f, ft ft o M

1—1 ro oj

o ro ♦* # ft © ro * — —

+ ^ « \J H M W H

+ + + » \i ro ro at

+ + +r NJ NJ |-| OJ at

vj+ + vj 1—11—1 OJ IV

co OJ

CO ©

00 «►

CO CO

W M * * M * Wm \J

o

CO

I

ro ro + # vj ^.

NJ + vj vj

+ » ro # » ro vj

— o

VJ OJ VJ OJ

* ft vj

l-l ft #

M M «

+ + —

vj « + —

HH # + VI

►—i i—1 ro o i»

vj 1-1

ro oj oj o

at as as nji aps m art

w # vj ro oj o a*

* VJ _ ft oj o M

+ + 1-1 oj ro *» <»

VJ VJ vj ro oj o »-t

# vj ro ro oj «» as w * 1-1 oj oj o at i-h 1-1 1-1 ro o oj at

M M U U U « Z

f < f t ro o o o at

ro ro ro ro o o co

\l M UOU » CO

rororo 0*0 09

ro uou «co go

1-1 ro o •»• •» 00 as

oj o o «» as 00 at

u « at at at: * H

at 00 o

• o « o i» ar: o oj M at 00 oj

aj ai H at co

co a: oo

oj «» co

oj ro oj

ro i-i vj

vj * *

U H t

OJ 1-1 VJ +

O 1-1 * ^»

O OJ *

o ro ft +t

» W M +

» orj +

« uro •

co oh +

O OJ VJ

O OJ 1-1

00 OJ VJ

00 »» ro 00 o

— \

^v I

VJ *

vj

vj

»-l I—1 vj

ro i-i i-i

co o ro

as o +

010^

1 " at t-a

\ 1 ■*► a-a -w»

\ I H O H

1-1 vj 1—1 ro

OJ 1-1 00 OJ

oj ro

ft VJ

ro » — +

«► vj

OJ l-l OJ VJ

ro vj 1—1 1—1

1-1 VJ 1-1 vj vj VJ

l-l #

VJ vj vj VJ vj vj

# •-"

VJ VJ

# vj

-^ \ I I

\ « # l-l —. I

I — U ft -~* s

\ + m ro + I

\ # ro ro vj s

\ # w ro * 1

<* o

** OJ

CO o

as co 00

— OJ + •» vj

ro ^

ro *» •► vj

M MZO)*M»M\| I

» co 1a aa at o at a* a* at

•> CO IB

o as at

ro w co a

oj ro oj 00

ro oj o «►

w ro w *

oj ro ro oj

ro oj oj o

oj ro ro o

oj ro oj oj

ro ro oj o

oj ro ro oj

ro oj

ro ro

oj o

OJ OJ

o OJ

o o

OJ OJ

o o

o v.

o o

•«• *»

o 00

00 00

V

\fiiiH

tt

iiSS:

ii

SSil

:■■ " - :■'

V

liiiaiiiri.fMtj'

«tjaaj«M«jiaa«a**<^p^a^

ill! II

s:sss|

^!

HiHiii!

5||pi||||

o

00

<*■ o •«» at

» CO 2 2 2

«► 00 at as ac <» 1-1

co z a at

lllJIJ.lH.il

ooojrooooojj. #

corOH»»o*'

ooorovjooooji—1--^

'OVJi—1OJCOW1-1 +

J »» ro^

GO OJ ro # H CO 1A U 4> ZUUHHOZUH

00 oj w ft ft oj as t^ vj

z » ro sj +

z co •

z « o

at z *

at arc 00

at co «

at at co

at at co

ro 1-1 vj +

M at at at at at co

H h at Z Z CO CO at at at at at 00 *» Hazzzzcoo H h a Z CO 00 at at at at at co at at 00 at at 00 00

a a co oj co » at at at at co <» at at at at at co

•-I vj

ro i-i

ro ro

oj ro

o o

ro oj

oj ro

OJ OJ

oj ro

o OJ

oj o

OJ OJ

4» O

OJ O

V» OJ

# ro

+ vj

+ #

vj vj vj

vj vj vj

ft ft ft

oj oj o

OJ 4* CO

•*» at at

00 at at

o «» co

W CO z

O 00 CO

O «» CO

•> CO CO

OJ OJ o

oj oj ro

oj ro vj

ro nj ^

«► OJ OJ l-l

O* O W W NJ CO 09 00 * « « a z 0 * • *

«» OJ f- O OJ o

ro * » i-i * ro

oj + -» + —

co o oj ro

«zo)mm«»WM

ZCO|fr*WM#^

nim ~

NJ * NJ M »

oj ro ro Nj +

ro ro ft nj *

+ ,-. + VJ

N ^- •»

* NJ

I

I

co at

at 00

4* 00

o «»

«► o

OJ o

ro ro

ro ro

NJ l-l

»-i »

NJ VJ

h-i 1—1

oj ro

ft OJ

nj 1-1

* nj

1* m at 00 00

00 at at 00 00 co

» CO »

o«co 000

ro 1-1 ro

ro nj nj

NJ H M

l-l * NJ

NJ NJ +

+ * •»

co at 00 00

at 00

at 00

o o

OJ OJ

OJ OJ

ro ro

ro ro

i-i ro

NJ VJ

•-1 vj

oj ro #

« oro

«» O OJ

«► ** o

00 CO CO

«» o o

«► O OJ

oj oj ro

l-l ft vj

ro 1-1 1-1

NJ l-l 1-1

•» * NJ

NJ NJ NJ

» + +

NJ * NJ

ro 1-1

i» o

o OJ

o OJ

OJ OJ

ft ro

ro ro

1-1 ro

nj VJ

1-1 ro

NJ II

NJ l-l

nj ro

+ + +

» NJ NJ

+ NJ NJ

* VJ »

NJ l-l NJ

» NJ NJ

l-l NJ VJ

I—I NJ 1—I

NJ « NJ

l-l NJ 1—1

NJ l-l l-l

NJ VJ VJ

* VJ + 1—1 + NJ

* l-l + l-l

* NJ

* l-l

* l-l NJ «.

* l-l

* l-l NJ VJ + l-l

* VJ

# VJ « VJ + + NJ #

# * 4- HH + NJ VJ |_| + + NJ NJ

« nj * ro

+ NJ l-l NJ

# » l-l l-l

nj 1-1 nj ro

H" NJ NJ VJ

OJ OJ

OJ OJ

ro ro

ro ro

vj l-l

nj *

1-1 #

* —

NJ ^v

NJ «

» +

VJ

^ + NJ N) I-II—II—II—I NJ

#NjNl#^-^ + MMH

-~ ^ 'v # # Nl VJ

+ ^ + h ro u

11 Nl NJ VJ

NJ + 4- + NJ

j-^^^ + ^^^-i^ 4. ^.^.

ro ro 1-1 ro + NJ

ro ro

ft ro

ro nj

ro ro

* nj .-. NJ

+ ft

NJ l-l

ro oj i-i ro oj ro

OJ OJ

ro ro

OJ OJ

ro oj hh ro

Nl ft

# Nl NJ «

# Nl

— + ~- ~- -~

+ — + + ^ + *

# Nl

* ^ ^ — -~

Nl Nl Nl W# '* VJ

+ + » Nl * *

NJ Nl *

# + # 4- •» *

* + * Nl VJ VJ

NJ NJ l-l

l-l Nl NJ NIMH

NJ NJ l-l

l-l l-l l-l

i-i 1-1 ro

l-l NJ l-l

ro ro ro

1-1 1-1 ro

ro >-i 1-1

ro ro oj

1-1 ro ro

oj ro ro

ro ro OJ

ro ro ro

OJ OJ OJ

ro oj oj

oj oj ro 000

OJ OJ OJ

O OJ OJ

000

OJ OJ OJ

OJ o o

ro oj o

nj 1-1 ro

NJ I—I I—1

ro ro ft ro 1-1 i-i ro ro

1-1 ro 1-1 ro ro 1-1 nj ro 1-1 ro ro 1-1 1-1 ro ro 1-1 ro ro ro oj

OJ l-l

ro ro ro ro ro 1—1 ro ro

OJ l-l

ro 1-1 ro ro

l-l l-l OJ l-l

ro 1-1

ro ro

►1 ro

ro ro

ro oj

ro ro

OJ OJ

ro oj

oj ro

oj o

OJ OJ

o OJ

oj o

OJ OJ

o ©

ro o

ro ro

ro

^-+#NI+J,###VJ -N + ^N • NlNI M Nl »

«•*■ + + + « NJ

u M NININI » Nl

NJ Nl Nl

i-i 1-1 ro

Nl Nl

ro 1-1

ro ro ro ro

OJ l-l

ro ro oj ro oj to ro oj o ro oj ro

OJ OJ

© ro

OJ OJ OJ OJ

© ro oj © o OJ o OJ ro © ro oj 1-1 © ni © ro oj ro ©

Figure 1: The image reproduced by IMAGE was originally a black-and-white photograph. The analog-to-digital converter used by the author registered a dark-to-light difference of 130, when the picture was processed. Magazine and book photos or artwork can also be reproduced satisfactorily.

February 1981 © BYTE Publications Iik 221

F =

file the data.

H =

help, display menu.

M =

set maximum and minimum values.

P =

print the data back

out.

Q =

quit and return to CP/M.

R =

read the file in.

S =

scan a new page.

T =

set the tone array.

Table 1: The menu

displayed

by

IMAGE.

acters, and there is a primary and secondary string. Two separate strings were chosen so the printer would not have to backspace to provide overstrike capability; characters from the secondary string print on top of those from the primary string. However, it does have to return the carriage without feeding a line.

For an example of what a user can do with this system, refer to figure 1. In order to achieve the desired contrast, it was necessary to use overstrike on the darker areas. This picture originally was a black-and-white photograph reproduced from a magazine page. The difference between the maximum and minimum values read from the A/D converter for this picture, was decimal 130. The higher this difference is, the more contrast the resulting printout will have and the better it will look.

Using IMAGE

The image processing program, IMAGE, is run as a transient program under Digital Research's CP/M operating system. If IMAGE is being used under some other system, the start-up procedure would change. The program is initially executed by typing in the following command line:

A> IMAGE filename

In this case, the data-storage file is identified as "filename.img". (The extension "img" is assumed by the program.) This will be used for all correspondence with the disk. When control is transferred to this program, a heading and initial menu are displayed, allowing the user to choose one of several options. (See table 1.) The user may type either F, H, M, P, Q, R, S, or T (uppercase or lowercase). Anything else is ignored and causes the full list to be printed.

F: File the Data

This writes out the data that was

Text continued on page 240

Listing 1: IMAGE, the control program for image processing. This version is written for CP/M version 1.4 (compatible with version 2.0) and can scan 255 lines of up to 255 characters. Overstrike capability is provided to increase contrast of output pictures by darkening areas as necessary. Try squinting your eyes or holding the images at different viewing distances to obtain a maximum of picture clarity (ie: the illusion's gestalt).

IMAGE.ASM NOVEMBER 4,1979

COPYRIGHT 1979, CLARK A. CALKINS

THIS PROGRAM ALLOUES A USER TO SCAN OVER AN IMAGE PLACED IN THE CP/M LIST DEVICE AND RECORD THE RELATIVE GRAPHIC DENSITY VIA AN A/D. IT IS ASSUMED THAT THE USER HAS PLACED A PHOTO SENSITIVE DEVICE ON THE HEAD OF THE PRINTER AND CAN READ THE RELATIVE ENTENSITY OVER AN A/D CHANNEL. REFER TO DR. DOBBS JOURNAL, OCTOBER 1979 (VOL 4, ISSUE 9, H39) FOR DETAILS ON DOING THIS.

TO USE THIS PROGRAM, TYPE: AHHAGE FILENAME<RET>

ONCE EXECUTING, THIS PROGRAM UILL ASK FOR THE OPTION THAT IS DESIRED. THE USER MAY;

1) SCAN A NEU IMAGE AND RECORD THE DENSITY DATA,

2) FILE THE EXISTING DATA AUAY ON THE FILE SPECIFIED,

3) READ IN DATA FROM A PREVIOUSLY SAVED SCAN FROM THE SPECIFIED FILE,

4) SET THE TONE ARRAYS THAT UILL BE USED TO PRINT BACK THE IMAGE TO ANY DESIRED SET OF CHARACTERS,

5) PRINT OUT THE IMAGE USING THE CURRENT TONE ARRAYS,

6) SET MAXIMUM AND MINIMUM VALUES.

THE FILE NAME SPECIFIED UILL BE GIVEN THE DEFAULT EXTENSION OF 'IMG'AND THIS MUST EXIST IF DATA IS TO BE READ BACK IN, OR IT UILL BE CREATED (IF NECESSARY) IF NEU DATA IS TO BE FILED AUAY. TO SCAN A NEU IMAGE, THIS CODE UILL ASK FOR THE DESIRED LINE LENGTH. TYPE IN THE LENGTH (IN DECIMAL) AND THEN YOU UILL BE GIVEN THE OPPORTUNITY TO POSITION THE PAPER BEFORE THE SCAN STARTS. ONCE STARTED, THE SCAN UILL CONTINUE UNTIL 2SS LINES HAVE BEEN SCANNED OR THE USER HAS TYPE ANY KEY (ONLY CHECKED AT THE END OF A LINE). THE RANGE OF VALUES READ UILL BE GIVEN AND CONTROL UILL RETURN TO THE OPTION SELECTION LEVEL. UHEN PRINTING THE DATA BACK OUT, TYPING ANY KEY (AGAIN AT THE END OF A LINE) UILL HALT THE PROCESS AND RETURN TO THE OPTION SELECTION LEVEL.

THIS PROGRAM UILL NOT CHECK MEMORY USAGE, SO BE SURE THAT THERE IS ENOUGH ROOM FOR THE IMAGE BEING SCANNED (ONE BYTE IS USED PER COLUMN POSITION, PER LINE.

0100

ORG

100H

0100 31D307

IMAGE

LXI

SP,STACK

JSETUP STACK

0103 117C04

LXI

D,HELLO

0106 0E09

HVI

C,9

0108 CD0S00

CALL

CPM

010B 216500

LXI

H,005CH+9

JSET IMAGE EXTENSION TO

010E 3649

HVI

H,'I'

0110 23

INX

H

0111 364D

MVI

H,'H'

0113 23

INX

H

0114 3647

MVI

M,'G'

'IMG'.

0116 11BS04

OPT

LXI

0119 OE09

MVI

011B CD0S00

CALL

011E 118105

UHAT

LXI

0121 CDF303

CALL

0124 E65F

ANI

0126 FE46

CPI

ASK FOR THE DESIRED OPTION. HERE UE DON'T UAIT FOR A CARRIAGE RETURN, JUST THE FIRST THING TYPED. INVALID RESP0NCES ARE IGNORED.

D,0PTI0N;UHAT DOES THE USER UANT TO DO?

C,9

CPM

D,QUESTN

ASK

5FH ;MAKE UPPER CASE FOR COMPARISONS.

'F' ;FILE THE DATA?

Listing 1 continued on page 224

222 February 1981 © BYTE Publications Inc

Circle 151 on inquiry card.

Udntex

IMPACT PRINTERS

150 CHARACTERS PER SECOND

80/136 COLUMNS PER LINE

The Series 6000 is perfect for applications where high reliability at a low cost is a major consideration. M icroprocessorcontrolled. Heavy duty operation.

Loaded with standard features. Tractor paper feed. Multi-part forms control. Top of form operation. Manual paper advance control. Built-in test capability. Cartridge ribbon. 9x7/9x9 dot matrix. Parallel or serial interfaces. Plus more.

Contact us today for a free print sample.

Odntex

Va'CJI IIC?A Division of North Atlantic Industries

60 Plant Avenue,

Hauppauge, NY 11787

(516) 582-6060 TWX 510-227-9660

For more information please call

800-645-5292

Intri

t It

ucing

The days of com plicated, unreliable, dynamic RAM are gone:

$199,

the ultrabyte memory board

QC 1 complete kit \ %t W ymVi teKmemoty)

Netronics consistently offers innovative products at unbeatable prices. And here we go again —with JAWS, the ultrabyte 64K S100 memory board. ONE CHIP DOES IT ALL JAWS solves the problems of dynamic RAM with a state-of-the-art chip from Intel that does it all. Intel's single chip 64K dynamic RAM controller eliminates high-current logic parts... delay lines... massive heat sinks... unreliable trick circuits. REMARKABLE FEATURES OF JAWS Look what JAWS offers you: Hidden refresh ... fast performance ... low power consumption ... latched data outputs... 200 NS 4116 RAMs... on-board crystal... 8K bank selectable ... fully socketed ... solder mask on both sides of board ... designed for 8080,8085, and Z80 bus signals... works in Explorer, Sol, Horizon, as well as all other well-designed S100 computers.

IBNEYOURCOMPUTERABIBBmOFMEMORY | P0WERWimJAWS—SAVEUPT0$300N K

IN1RODUCTORYUMI1ED-OFFERSPECIAI PRICES! |

UNDECIDED? JW A WHO m JAWS IN YOUR COMPUTER ON OUR W-OAYMOHIY- BACK OmKSPCCIFYYOURCOMPUTm.

CONTINENTALU.S.A.CREDITCARO BIKERS OUTSIDECONNECncirrCAU

CALL TOLL FREE 800-2437428

From Connecticut Or For Atiiitinci, (203) 354-9375 Dept

l^k ||[Tnn|||PQRESEARCH & b:

ImniinUmuUDEVELOPMENTLTDi

333 Litchfield Road, New Milford.CT 06776 Please send the items checked below: D JAWS 16K RAM kit, No. 6416. S199.95.* G JAWS 16K RAM fully ammblid, tested, burned in,

No.6416W.S229.95.* D JAWS32KRAMtot,No 6432, (reg. price S329.95!

SPECIAL PRICE '299.95.* G JAWS 32K RAM fully aitamblad, tailed, burnad in,

No. 6432W. (reg. price S369.95I, SPECIAL PRICE

$339.95. * G JAWS 4BK RAM kit, No. 6448, (reg. price S459.95I,

SPECIAL PRICE 1399.95.* D JAWS 46K fully aiiamblad, tatted, burned in, No.

6448W, (reg. price S509.95I, SPECIAL PRICE

♦449.95.* CI JAWS 64K RAM kit, No.6464. (reg. priceS589.95).

SPECIAL PRICE t499.95.* G JAWS 64K RAM fully aitamblad, tatted, burned in,

No. 6464W, (reg. price S649.95), SPECIAL PRICE

1559.95.* CI Eipamion kit, JAWS 16K RAM moduli, to expand

eny of the above in 16K blocks up to 64K. No. 16EXP,

S129.95*

*AII prices plusS2 postage and handling. Connecticut residents add sales tax. Total enclosed: S.

CI Personal Check G Money order or Cashiers Check

G VISA G MASTER CHARGE (Bank No )

Acct. No. Exp. Dete

Signature

Print Name

Address —

City

State

G Send me more information

_Zip.

Listing 1 continued:

0128 CAA302

JZ

FILE

012B FE50

CPI

'?'

JPRINT THE FILE

012D CA0502

JZ

PRT

0130 FE54

CPI

'T'

JSET THE TONES

0132 CA5A03

JZ

TSET

0135 FE53

CPI

''S'

;SCAN A NEU PACE

0137 CA4C01

JZ

SCAN

013A FES1

CPI

'Q'

•QUIT PR0CESSIN6

013C CA0000

JZ

0

013F FE52

CPI

'R'

;read in the file?

0141 CA0F03

JZ

READF

0144 FE4D

CPI

*N'

•SET HAX AND HINS

0146 CA7D03

JZ

SETKAX

014? C31601

JMP

OPT

;N0T RECOGNIZED

014C

AF

014D

32D307

0150

3D

0151

32D407

0154

111D06

0157

OE09

0159

CD0500

015C

CD9C03

015F

32D507

0162

1E0D

0164

CD0A04

0167

11?F05

016A

CDF303

016D

1604

016F

3E01

0171

320807

0174

OEFF

0176

21D707

017?

3AD507

017C

47

017D

CDCF03

0180

77

0181

3AD307

0184

BE

0185

D28C01

0188

7E

018?

32D307

018C

3AD407

018F

BE

0190

DA9701

0193

7E

0194

32D407

0197

23

0198

14

0199

F2A501

019C

3A0807

019F

3C

01A0

320807

01A3

1600

01A5

1E20

01A7

CD0A04

01AA

05

01AB

C27D01

01AE

1E0D

01 BO

CD0AO4

01B3

1E0A

01B5

CD0A04

01D8

CDFD03

01BB

DACF01

01 BE

D5

SCAN ACROSS THE PAGE AND COLLECT DATA FROM THE A/D. AT FIRST ASK THE USER FOR THE LINE LENGTH TO USE (A DECIMAL NUMBER). THEN GIVE HIM/HER AN OPORTUNITY TO POSITION THE PAGE BEFORE STARTING. CONTINUE SCANNING UNTIL 255 LINES HAVE BEEN CHECKED OR THE USER HAS TYPED A KEY (CHECKED AT THE END OF A LINE ONLY). UHEN DONE, REPORT THE MAXIMUM AND MINIMUM VALUES READ FROM THE A/D. HE HOPE THAT THE USER HAS ENOUGH MEMORY FOR ALL OF THIS SCAN DATA (ONE BYTE PER COLUMN PER LINE) AS A CHECK IS NOT MADE (BUT COULD BE IN NECESSARY).

SCAN

OUTLP

INLP

DOI

D02

D03

XRA

STA

DCR

STA

LXI

MVI

CALL

CALL

STA

MVI

CALL

LXI

CALL

MVI

MVI

STA

MVI

LXI

LDA

MOV

CALL

MOV

LDA

CMP

JNC

MOV

STA

LDA

CMP

JC

MOV

STA

INX

INR

JP

LDA

INR

STA

MVI

MVI

CALL

DCR

JNZ

MVI

CALL

MVI

CALL

CALL

JC

PUSH

;set maximum and minimum values

;find line length from user

;tell user to ready the paper ;this is a sector counter

A

MAX

A

MIN

D,LLNGTH

C,9

CPM

GETNUM ;GET NUMBER FROM USER

LNGTH

E,13 ;RETURN THE CARRIAGE

PRINT

D,P0S

ASK

D,4

A,1

NSECT

C,255 ;MAXIMUM ROU COUNT

H.BUFF ;SET BUFFER ADDRESS

LNGTH ;C0LUHMN COUNT

B,A

READ

M,A

MAX

M

DOI

A,M

MAX

MIN

M

D02

A,M

MIN

H

D

D03

NSECT

A

NSECT

D,0

W '

PRINT

;get a value from the a/d

;keep track of max AND MIN VALUES

jcount bytes jsector limit yet? ;yes, count them

;move one column

INLP

E,13

PRINT

E, 1 0

PRINT

CHECK

TOUT

D

;NEXT LINE

;CHECK THE KEYBOARD

Listing 1 continued on page 226

224 February 1981 © BYTE Publications Inc

Are you prepared for the explosive transformation? Right in your own home? Electronic mail. Personalized •. investment analysis. Foreign language tutorial. Home energy management. Robots. Computer music. Secretarial service. Diet and menu planning. And more, more, more.

onCompating™ the new McGraw-Hill quarterly, prepares you for the enormous changes coming during the

Pcrso nitouc

''' '■':'■ . ■

Computer YOU?

1980's (Some are already here).

onComputing™ explains in nontechnical

language what personal computers are,

how they work, and how you can use

them at home, for fun and profit.

Don't let the personal computer

explosion catch you off guard. Know

what's happening and help make it

happen! Prepare now for the exciting

future with a subscription to

onComputing™!

Call Toll-Free

800-258-5485

Start your subscription today.

onCompottag™ Subscription Dept. P.O. Box 307, Martinsville, NJ 08836

DOMESTIC subscription rata

□ U.S. 1 vr. (4 issues) @ $850 □ Canada & Mexico, 1 yr. (4 issues) @ S 10.00

FOREIGN (to expedite service, please remit in U.S. funds drawn on a U.S. bank.)

□ Europe (and all other countries, except above), 1 yr. @ S 12.00 — surface delivery.

D Bill Visa D Bill Master Charge □ Bill me (North America only)

© onComputing, Inc. 1980

Card Number

Expiration

<

Signature

Name (please print)

c

Street/Apartment Number !

City

State/Province/Country Code

7B21

Circle 152 on Inquiry card.

' MBC Systems, Inc.

(203) 342-2747

I ss»"a

NORTH STAR HORIZON:

HRZ-2-32K-D-Factory ASMS2275 HRZ-2-32K-Q-Factory ASM$2675 64K DD or Q Also Available

HDS-18-F $4449

Northword DQ $ 359

INFO-Manager $ 365

Mail Manager $ 269

General Leger $ 775

ACC. REC. OR ACC. PAY..$ 445

Word Star $ 350

Medical-Dental SYS $2500

COMMODORE (PET):

2001-32K-BorN Keyboard $1090 16K Also in Slock....$859!!! 8032 (80 Column Screen)$1599 2040 Dual Floppy Drive $1090 8050 Dual Floppy (1MEG)$1599 2022 Tractor Printer...$ 749

Word PRO IV $ 290

VISICALC $ 195

APPLE II PLUS Call For Price!

ATARI 800 $ 849

TI 99/4 ConsoleSMonitor .. $990 INTERTEC SUPERBRAIN:

32K RAM $2595

64K RAM $2695

PRINTERS

Letter Quality:

NEC 5510 or 5530 $2550

NEC 5520 KSR $2950

DIABLO 630 $2390

C.ITOH $1690

Dot Matrix:

CENTRONICS 730 $ 599

737-1 $ 799

799 $999

EPSON MX-80 $ 599

PAPER TIGER 460G $1250

BASE II MST $ 649

DISPLAY TERMINALS

HAZELTINE 1420 $ 949

" " 1500 $ 999

INTERTUBE III $ 775

TELEVIDEO 920C $ 849

Since 1977 complete sales and service. Most items in stock, prices are subject to change. Visa and Master Charge welcome Most items shipped by UPS.

MBC Systems, Inc.

Multi Computer Business Systems, Inc. 28 MARLBOROUGH STREET PORTLAND, CONN. 06480

(203)342-2747 TWX 710-428-6345 k M-F 9-6 SAT.9:30-3:00

Listing 1 continued:

01BF

110000

01C2

IB

01C3

E3

01C4

E3

01C5

7B

01C6

B2

01C7

C2C201

01CA

D1

0 1 CB

0D

01CC

C27901

01CF

3EFF

01D1

91

01D2

328607

01 D5

OC

0 1 D6

OB

om?

0E01

01 D9

C40500

01DC

214A06

01 HF

3AB307

01E2

5F

01E3

1600

01ES

010A03

01E8

CB3404

01EB

215A0A

01EE

3AD407

01F1

5F

01F2

1600

01F4

010A03

01F7

CD3404

01FA

112E06

01FD

0E09

01FF

CD0500

0202

C31E01

0205

119F05

0208

CBF303

020B

3AB607

020E

47

020F

21B707

0212

EB

0213

C5

0214

211107

0217

3A1007

021A

B5

021B

C04E02

021E

B1

021F

215307

0222

3A5207

0225

A7

0226

D5

0227

C44E02

022A

El

022B

C0F003

022E

BA4502

0231

1E0A

0233

CD0A04

0236

3AD507

0239

5F

023A

1600

023C

19

023B

CI

023E

05

023F

C21202

0242

C31E01

0245

CI

0246

0E01

0248

CD0500

024B

C31E01

BELAY

TOUT

PRTMX

LXI

BCX

XTHL

XTHL

H0V

0RA

JNZ

POP

DCR

JNZ

HUI

SUB

STA

INR

BCR

HUI

CNZ

LXI

LBA

HOU

HUI

LXI

CALL

LXI

LBA

HOU

HUI

LXI

CALL

LXI

HUI

CALL

JMP

[i,0 D

,-BELAY TO ALL0U RETURN OF CARRIAGE

A,E

B

BELAY

D

C

0UTLP

A,255

C

LINES

C

C

C,1

CPH

H,HAXU

HAX

E,A

D,0

8,3*254+10 |USE DECIMAL

BT0A

H,MINU

MIN

E,A

8,0

8,3*256+10

BT0A

B.HAXHIN ;PRINT THIS DATA N0U

C,9

CPM

UHAT

;bone uith page?

jc0hpute number of lines used

JRETRIEVE CHARACTER TYPED

;UNLESS THERE UAS NONE.

JSETUF THE MAX AND MIN UALUES FOR THE

JUSER TO SEE

PRINT OUT THE IHAGE. THERE ARE TU0 TONE ARRAYS THAT UILL BE USEB FOR EACH LINE SUCH THAT 'OvERSTRIKE' MAY BE USED UITH A PRINTER THAT B0ES NOT BACKSPACE. EACH TONE ARRAY UILL BE C0NSIBEREB SEPERATLY (THEY BON'T HAVE TO BE THE SAME LENGTH). THIS WILL ALLOU THE USER TO HAUE LOTS OF CONTROL OUER THE OUTPUT, IF HE/SHE CAN EUER BECIDE ON UHICH CHARACTERS TO USE.

PRT

PRTLP

POUT

LXI

CALL

LDA

HOU

LXI

XCHG

PUSH

LXI

LDA

PUSH

CALL

POP

LXI

LDA

ANA

PUSH

CNZ

POP

CALL

JC

HUI

CALL

LDA

HOU

HUI

DAD

POP

DCR

JNZ

JHP

POP

HUI

CALL

JHP

D.POS

ASK

LINES

B,A

H,BUFF

H.T0NE1

NUHBR1

8

PRINTLN

8

H.T0NE2

NUHBR2

A

8

PRINTLN

H

CHECK

POUT

E, 10

PRINT

LNGTH

E,A

8,0

[i

JTELL USER TO REABY PAPER

;THIS IS HOU LONG THE SCAN IS

THE SCAN BATA STARTS HERE.

HOVE BATA AB8RESS TO (BE)

SAUE LENGTH

THIS IS THE PRIHARY TONE ARRAY

ANB ITS LENGTH

SAUE BATA ADDRESS

PRINT THIS LINE

RESTORE DATA ADDRESS

HOU USE THE SECONDARY TONE ARRAY

NOTE THAT THIS IS ZERO IF THERE IS

NO SECONDARY ARRAY.

SAUE ADDRESS

;SET (HL) TO START OF LINE JUST PRINTED.

;CHECK THE KEYBOARD

;AND QUIT IF ANYTHING IS PRESENT

;add A (LF> to the output FOR THE NEXT

;line.

jcompute start of next line

;(hd has start address nou ;decrehent line counter.

PRTLP

UHAT

B

C,1

CPH

UHAT

;back TO option selection level

;SET STACK STRAIGHT ;GET CHARACTER TYPED

;but ignore

Listing 1 continued on page 228

226 February 1981 © BYTE Publications Inc

Computer experts (the pros) usually have big computer experience. That's why when they shop system software for Z80 micros, they look for the big system features they're used to. And that's why they like Multi-User OASIS. You will too.

DATA INTEGRITY: FILE & AUTOMATIC RECORD LOCKING

The biggest challenge for any multi-user system is co-ordinating requests from several users to change the same record atthe same time.

Without proper co-ordination, the confusion and problems of inaccurate or even destroyed data can be staggering.

Our File and Automatic Record Locking features solve these problems.

For example: normally all userscanviewa particular record atthe same time. But, if that record is being updated by one user, automatic record locking will deny all other users access to the record until the up-date is completed. So records are always accurate, up-to-date and integrity is assured.

Pros demand file & automatic record locking. OASIS has it.

SYSTEM SECURITY:

LOGON, PASSWORD

& USER ACCOUNTING

Controlling who gets on your system and what they do once they're on it is the essence of system security.

(THEN COMPARE.)

Without this control, unauthorized users could access your programs and data and do what they like. A frightening prospect isn't it?

And multi-users can multiply the problem.

But with the Logon, Password and Privilege

Level features of Multi-User

OASIS, a system manager can specify for each user which programs and files may be accessed — and for what purpose.

Security is further enhanced by User Accounting —a feature that

lets you keep a history of which user has been logged on, when and for how long.

Pros insist on these security features. OASIS has them.

EFFICIENCY: RE-ENTRANT BASIC

A multi-user system is often not even practical on computers limited to 64K memory.

OASIS Re-entrant BASIC makes it practical.

How?

Because all users use a single run-time BASIC module, to execute their compiled programs, less

memory is needed. Even if you have more than 64K, your pay-off is cost saving and more efficient use of all the memory you have available—because it services more users.

Sound like a pro feature? It is. And OASIS has it.

AND LOTS MORE.

Multi-UserOASIS supports as many as 16 terminals and can run in as little as 56K memory. Or, with bank switching, as much as 784K.

Multi-Tasking lets each user run more than one job at the same time.

And there's our BASICa compiler, interpreter and debugger all in one. An OASIS exclusive.

Still more: Editor; Hard & Floppy Disk Support; Keyed (ISAM), Direct & Sequential Files; Mail-Box;

Scheduler; Spooler; all from OASIS.

Our documentation is recognized assome of the best, most extensive, in the industry. And, of course, there's plenty of application software.

Put it all together and it's easy to see why the real pros like OASIS. Join them. Send your order today.

OASIS IS AVAILABLE FOR

SYSTEMS: Alios: Cornpucorp:Cromemco: Delta Producls: Digital Group: Digital Microsystems; Dynabyte; Godbout: IBC; Index; Inlersystems; North Star: Onyx: SD Systems; TRS 80 Mod II: Vector Graphic: Vorimex

CONTROLLERS: Bell Controls: Cameo; Corvus; Konan; Micromation: Micropolis: Tarbell; Teletek: Thmkertoys: X Comp

Write for complete.

free Application Software Directory,

PLEASE SEND ME:

Price

with

Manual

Product

Manual

Only

OPERATING SYSTEM

(Includes:

EXEC Language;

File Management,

User Accounting;

Device Drivers;

Print Spooler;

General Text

Editor; etc.)

SINGLE-USER

$150

SI 7.50

MULTI-USER

350

17.50

BASIC COMPILER/

INTERPRETER/DEBUGGER

too

1500

RE-ENTRANT BASIC

COMPILER/INTERPRETER/

DEBUGGER

150

15.00

DEVELOPMENT PACKAGE

(Macro Assembler;

Linkage Editor;

Debugger)

150

25.00

TEXT EDITOR &

SCRIPT PROCESSOR

150

15.00

DIAGNOSTIC &

CONVERSION UTILITIES

(Memory Test;

Assembly Language;

Conveners; File

Recovery; Disk Test:

File Copy from

other OS; etc.)

100

15 00

COMMUNICATIONS

PACKAGE

File Send & Receive)

100

15.00

PACKAGE PRICE

(All Of Above)

SINGLE-USER

500

60.00

MULTI-USER

350

60.00

FILE SORT

100

15.00

' COBOL-ANSI '74

750

35.00

Order OASIS from:

Phase One Systems, Inc.

7700 Edgewater Drive, Suite 830

Oakland, CA 94621

Telephone (415) 562-8085 TWX 910-366-7139

NAME

STREET (NO BOX=)

CITY

STATE ZIP

AMOUNTS

(Attach system description;

add S3 for shipping,

California residents add sales tax)

□ Check enclosed □ VISA

□ UPS C.O.D. □ Mastercharge

Card Number

Expiration Date

Signature

MAKES MICROS RUN LIKE MINIS

Circle 153 on Inquiry card.

MORE FOR YOUR ^

RADIO SHACK TRS-80 MODEL I !

THE DATAHANDLER

DATABASE MANAGEMENT SYSTEM IN MMSFORTH

Now the power, speed and compactness of MMSFORTH drive a major applications program for many of YOUR home, school and business tasks! Imagine a sophisticated database management system with flexibility to create, maintain and print mailing lists with multiple address lines, Canadian or the new 9-digit U.S. ZIP codes, and multiple phone numbers, plus the speed to load hundreds of records or sort them on several fields in 5 seconds! Manage inventories with selection by any character or combination. Balance checkbook records and do CONDITIONAL reporting of expenses or other calculations. File any records and recall selected ones with optional upper/lower case match, in standard or custom formats. Personnel, membership lists, bibliographies, catalogs of record, stamp and coin collections—you name it! ALL INSTANTLY, without wasted bytes, and with cueing from screen so good that non-programmers quickly master Its use! With manual, sample data files and custom words for mail list and checkbook use.

Technical: Handles data as compressed indexed sequential subfiles of up to 25K characters (9K in 32K RAM). Access 1-4 data diskettes. Modified Quicksort. Optionally precompiles for 5-second program load. Selfadjusts for many routine mods. Structured and modular MMSFORTH source code ideal for custom modifications.

THE DATAHANDLER V1.1, a very sophisticated database management system operable by non-programmers (requires Disk MMSFORTH, 1 drive & 32K RAM); with manuals $59.95*

FORTH

THE PROFESSIONAL FORTH FOR TRS-80 MODEL I

(Over 1,000 systems in use)

MMSFORTH Disk System V1.9 (requires 1

disk drive & 16K RAM) )ust $79.95*

MMSFORTH Cassette System V1.8 (requires Level II BASIC & 16K RAM) $59.95*

AND MMS GIVES IT PROFESSIONAL SUPPORT

Source code provided

MMSFORTH Newsletter

Many demo programs aboard

MMSFORTH User Groups

Programming staff can adapt

THE DATAHANDLER to YOUR needs.

MMSFORTH UTILITIES DISKETTE: includes FLOATING POINT MATH (L.2 BASIC ROM routines plus Complex numbers, Rectangular-Polar coordinate conversions, Degrees mode, more), plus a full Forth-style Z80 ASSEMBLER; plus a powerful CROSSREFERENCER to list Forth words by block and line. All on one diskette (requires MMSFORTH, 1 drive & 16K RAM), . . $39.95'

FORTH BOOKS AVAILABLE

MICROFORTH PRIMER (comes with

MMSFORTH) separately $15.00*

USING FORTH — more detailed and advanced than above $25.00*

THREADED INTERPRETIVE LANGUAGESadvanced, excellent analysis of

MMSFORTH-like language $18.95*

CALTECH FORTH MANUAL — good on

Forth internal structure, etc $10.00*

* — Software prices include manuals and require signing of a single-system user license. Add $2.00 S/H plus $1.00 per additional book; Mass. orders add 5% tax. Foreign orders add 15%. UPS COD, VISA & M/C accepted; no unpaid purchase orders, please.

Send SASE lor free MMSFORTH information. Good dealers sought

Get MMSFORTH products from your computer dealer or

MILLER MICROCOMPUTER SERVICES (B2)

61 Lake Shore Road, Natick, MA 01760 (617)653-6136

Listing 1 continued

024E

4F

024F

3AD407

02S2

47

0253

3AD307

0256

?0

025?

0600

025?

?)

025A

DA6102

025D

04

025E

C35902

0261

78

0262

320707

0265

A7

0266

C8

026?

EB

0268

D5

026?

3AD507

026C

47

026D

3AD407

0270

96

027)

2F

0272

3C

0273

F5

0274

3A0707

0277

5F

0278

F1

027?

1600

027B

?3

027C

DA8302

027F

14

0280

C37B02

0283

7?

0284

3D

0285

BA

0286

DA8A02

028?

7A

028A

D1

028B

D5

028C

83

028D

5F

028E

3E00

02?0

8A

02?)

57

02?2

IA

0293

5F

02?4

CD0A04

0297

23

0298

05

02??

C26D02

029C

1E0D

029E

CD0A04

02AI

D1

02A2

C?

PRINT OUT ONE LINE OF IMAGE DATA. ONE ENTRY, (HL) POINTS TO THE TONE ARRAY TO USE AND (A) CONTAINS ITS LENGTH. THE SCAN DATA TO USE IS POINTED TO BY (DE). ALL REGISTERS ARE USED BY THIS ROUTINE AND NOT RESTORED.

PRINTLN

DIVLP

D1

0UTLP1

INLP1

DIVLP1

D2

D3

MOV

LDA

MOV

LDA

SUB

MVI

SUB

JC

INR

JMP

MOV

STA

ANA

RZ

XCHG

PUSH

LDA

MOV

LDA

SUB

CHA

INR

PUSH

LDA

MOV

POP

MVI

SUB

JC

INR

JMP

MOV

DCR

CMP

JC

MOV

POP

PUSH

ADD

MOV

MVI

ADC

MOV

LDAX

MOV

CALL

INK

DCR

JNZ

MVI

CALL

POP

RET

C,A

MIN

B,A

MAX

B

B,0

C

D1

B

DIVLP

A,B

SCALE

A

D

LNGTH

B,A

MIN

M

A

PSU

SCALE

E,A

PSU

D,0

E

D2

D

DIVLP1

A,C

A

D

D3

A,D

D

D

E

E,A

A,0

D

D,A

D

E,A

PRINT

H

B

INLP1

E,I3

PRINT

D

JSAVE LENGTH OF TONE ARRAY. •COMPUTE (MAX-MIN)/LENGTH

-save result here -reject bad image data

;(hl)=scan data, (de)=t0ne array "and save this on the stack ;c0lumn limit

jcompute: (data-mini/scale ;nou <a>=min-data

;nou (a>=dtat-nin

•DON'T ALL0U IT TO BE TOO BIG

; ITS 0K, JUST USE IT.

•GET THE A(TH> BYTE FROM THE TONE STRING

•GET THE BYTE TO PRINT ;next BYTE

;ADD (CR)

JCLEANUP STACK ; AND BACK OUT

FILE THE DATA AUAY ON THE SUER SPECIFIED FILE. ON ENTRY TO IMAGE, THIS FILENAME UAS SPECIFIED (HOPEFULLY) AND UE HAVE ALREADY ADDED THE EXTENSION 'IMG' TO IT. IF THE INDICATED FILE ALREADY EXISTS, IT UILL BE DELETED AND A NEU FILE IS CREATED. THE INFORMATION SAVED UILL BE THE SCAN DATA ARRAY ITSELF, THE MAXIMUM AND MINIMUM VALUES IN THIS ARRAY, THE NUMBER OF SCAN LINES PRESENT, AND THE LENGTH OF EACH LINE. THIS DATA MAY BE READ BACK IN AT ANOTHER TIME UITH THE 'R' COMMAND.

JCHECK FOR ANYTHING TO FILE

Listing 1 continued on page 230

02A3

3A0807

FILE

LDA

NSECT

02A6

A7

ANA

A

02A7

CA0403

JZ

NOTHING

Are important letters and reports leaving your office with spelling errors?

ELLGUARD

can proofread 10,000 words in one minute.

SPELLGUARD is a revolutionary new computer program that finds spelling mistakes and typographical errors in documents prepared with CP/M1 or CDOS5 compatible word processors and text editors.

In less than one minute, SPELLGUARD proofreads 20 pages of text (10,000 words) and identifies all misspelled or mis-typed words based on its 20,000-word dictionary* After proofreading, SPELLGUARD asks the operator to review words identified as potential errors and judge each as correct or incorrect. Correct words may be added to the dictionary. SPELLGUARD marks incorrect words in the text so the operator can use a word processor or text editor to easily find and correct them.

SPELLGUARD is Easy to Use

• full proofreading capabilities are mastered after a few minutes of instruction.

• comprehensive user's manual contains step-by-step examples of all SPELLGUARD features.

SPELLGUARD is Powerful

• text files to 85 pages (CP/M 1.4), and 2,800 pages (CP/M 2.0).

• includes a 20,000-word, expandable dictionary.

• contains powerful commands to construct customized dictionaries for special areas, e.g., medicine, real estate, law, insurance, engineering.

SPELLGUARD is Reliable

• thoroughly tested in actual use.

• 30-day money-back limited warranty.

Minimum System Requirements: 8080/85, Z80 CPU with 32K memory: CP/M' 1.4 (dictionaries to

256K bytes), CP/M' 2.0 or later (dictionaries to 4 MB), or CDOS; word processor or text editor

compatible with SPELLGUARD (currently several excellent new CP/M word processors, and

WordStar2, WordMaster2, Magic Wand3, Electric Pencil4, and ED).

Trademarks: 'Digital Research (registered). 2MicroPro Int'l Corp., ;'Small Business Applications,

"■Michael Shrayer Software, 5Cromenco.

*Time estimates based on 4Mhz 8085 with 48K memory, CP/M 2.1 double density 8" floppy drive,

10,000-word text file.

INNOVATIVE SOFTWARE APPLICATIONS

Box 2797, Menlo Park, California 94025 415-326-0805

The price of SPELLGUARD includes rapid turnaround and delivery by UPS or airmail. Sales will be made only if the purchasers' word processor is compatible with SPELLGUARD. Software license agreement is required.

□ Send me a free, detailed description of SPELLGUARD.

□ Send me SPELLGUARD at $295.00. (Manual and diskette(s). Formats: 8" CP/M single density Shugart compatible, and 5'/4" Northstar double.)

□ Send me copies of the

SPELLGUARD manual at $20.00 each. (Airmail, credited toward purchase.)

□ Send COD (add $10.00 handling). California residents add 6% tax. Add $10.00 for foreign shipment.

Check enclosed for$ .

(Certified check, COD, and money order shipped immediately.)

ORGANIZATION

WORD PROCESSOR

COMPUTER SYSTEM

DISK FORMAT

Checks payable to ISA

Box 2797, Menlo Park, CA 94025.

STATE-OF-THE-ART SOFTWARE

Circle 154 on inquiry card.

BYTE February 1981 229

The joy of music —

without years of practice!

ALF offers the very finest in music hardware and software for the Apple® II. You can enter your own songs from sheet music and play them back very easily — our detailed manual shows you how, step by step. And there's a growing library of preprogrammed songs available too — now over 115 songs on 7 "albums", priced under $15 each. ALF's highly acclaimed music software has many features found on no other Apple music product — and no customer has ever reported a "bug" or error.

Whether you pick our exciting 9-voice MCI music card at just $195, or our gourmet 3-voice MC16 card at $245, you'll get ALF's topquality hardware that's famous for reliability and clean sound (we've been designing computer-controlled musical instruments since 1975).

So see your Apple dealer today, and be sure to specify ALF music cards for the best performance. When you've seen ALF's total music package, you'll know why some music cards are more equal than others!

Please mention this magazine when requesting information from:

<^|\ A L F Products Inc.

^&? 1448 Estes Denver. CO 80215 (303) 234-0871 Apple is a trademark of Apple Computer Inc.

Listing 1 continued:

DISK COPYING

Dependable, no-hassle copying of Apple-compatible disks (all formats, including copy-protected). Fast service on 50 copies or thousands of copies. Mix titles for quantity discounts. Call or write for more information.

ALF Products Inc.

1448 Estes Denver, CO80215 (303)234-0871

02AA 02AD 02AF 02B2 02B5 02B7 02BA 02BD 02BF 02C2 02C3 02C6 02C9 02CB 02CE 02D1 0204 02B5 02B8 02DB 02DC 02BD 02DE 02E0 02E3 D2ES 02E8 02EB 02EC D2ED 02F0 02F3 02F4 02F5 02F6 02F? 02FC 02FE 0301

115C00

0E13

CD0500

115C00

0E16

CD0500

115C00

0E0F

CD0500

3C

C2D102

11B805

0E09

CD0500

C30000

21B307

AF

327C00

3A0807

F5

E5

EB

0E1A

CD0500

0E15

115C00

CD0500

E1

A7

C2C602

118000

1?

F1

3D

C2DB02

115C00

0E10

CD0500

C31E01

0304 115F06 0307 0E09 030? CD0500 030C C31E01

030F 0312 0314 0317 0318 03 IB 03 IE 031F 0322 0323 0324 0325 0327 032A 032D 032F 0332 0333 0336 0339 033A 033B 033C 033B 0340 0341 0344 0347 0349

11scoo

0E0F

CD0500

3C

CA4F03

21D307

AF

327C00

F5

E5

EB

0E1A

CD0500

115C00

0E14

CD0500

A7

C24003

118000

El

19

F1

3C

C32203

F1

320807

11SCOO

0E10

CD0500

ERR

F1

FILELP

LXI

Hvl

CALL

LXI

Hvl

CALL

LXI

HVI

CALL

INR

JNZ

LXI

hvl

CALL

JHP

LXI

XRA

STA

LDA

PUSH

PUSH

XCHG

Hvl

CALL

Hvl

LXI

CALL

POP

ANA

JNZ

LXI

DAD

POP

DCR

JNZ

LXI

Hvl

CALL

JHP

NOTHING LXI Hvl

CALL JHP

D,005CH

C,19

CPH

D.005CH

C,22

CPH

D,005CH

C ,15

CPH

A

F1

D,ERR1

C,9

CPH

0

H,HAX

A

005CH+32

NSECT

PSU

H

C,26

CPH

C,21

D,005CH

CPH

H

A

ERR

D, 1 28

D

PSU

A

FILELP

D,005CH

C, 1 6

CPH

UHAT

D,NQNE C,9 CPH UHAT

;use default fcb ;delete the file

;create it n0u ;and open it.

;no rooh

;this is uhere it is stored. ;set initial sector counter to zero ;in default fcb. ;and this is hou long

;set the transfer address

jurite this sector

;check status of last urite ;hust be out of space ;c0hpute address of next

;CL0SE THE FILE NQU

;TELL USER TO SCAN S0HETHING FIRST.

READ IN THE FILE THAT UAS GIVEN IN THE INITIAL C0HHAND.

READF

READLP

READDN

LXI

Hvl

CALL

INR

JZ

LXI

XRA

STA

PUSH

PUSH

XCHG

Hvl

CALL

LXI

Hvl

CALL

ANA

JNZ

LXI

POP

DAD

POP

INR

JHP

POP

STA

LXI

Hvl

CALL

D,005CH ;0PEN THIS FILE

C, 15 CPH

A JUAS THIS FILE PRESENT ? NOFILE

H,HAX ;PUT THE DATA HERE A ;SET INITIAL SECTOR COUNTER TO ZERO 005CH+32;IN DEFAULT FCB. PSU H

;SET THE TRANSFER ADDRESS C,26 CPH

D.005CH ;READ A SECTOR C,20 CPH A READDN

D, 128 H D

PSU A

READLP PSU NSECT

D,005CH ;CL0SE THE FILE

C,16

CPH

Listing 1 continued on page 232

fZERO IS A GOOD READ

;C0HPUTE NEXT ADDRESS ;C0UNT THEH SECTORS READ.

;SAVE SECTORS READ

230 February 1981 © BY! E Publications Inc

Circle 156 on inquiry card.

Ten reasons

l

BASF FlexyDtok 1 No.

rr%!3 $r

More than four decades of experience in magnetic media-BASF invented magnetic recording tape, the forerunner of today's wide range of magnetic media, back in 1934, and was the first independent manufacturer of IBM-compatible floppy disks.

Tough Tyvek sleeve —no paper dust, no static electricity.

Special self-cleaning jacket and liner help eliminate data errors and media wear and tear.

BASF BASF RexyDisk

Center hole diameter punched to more accurate standards than industry specifications, for top performance.

Packaging to suit your requirements - standard flip-top box, Kassette 10® storage case, or bulk pack.

Bi-axially oriented polyester substrate - for uniform and reliable performance year after year.

Cross-linked oxide coating-for low head wear and long troublefree media life.

Total capability-one of two manufacturers in the world that iimakes both 8" and 5.25" models, has tape and disk experience, and manufactures floppy disk drives.

Double lubrication-lubricants both in the formula and on the disk surface, to minimize media wear due to head friction.

100% certification-every single disk is tested at thresholds 2-3 times higher than system requirements, to be 100% error-free.

For the name of your nearest supplier, write BASF Systems, Crosby ■rive, Bedford, MA 01730, or call 617-271-4030. See us at the NCC, Booth 1121

BASF

Floppy Disks Mag Cards Cassettes Computer Tapes Disk Packs Computer Peripherals

Circle 157 on Inquiry card.

PERSONAL

COMPUTER

SYSTEMS topple computer

■ Sales and Service

APPLE II, 16K, List $1195 $ 989

32K, List $1395 $1169

48K 1259

ATARI® 400™, List $630 OUR PRICE ONLY $499

820 PRINTER, List $599.95 $499

810 DISK DRIVE, List $699.95 $589

only $2799

• Extended BASIC Language

• Advance Graphics

• CRT Built-in Display

• Magnetic Tape Cartridge for Storage

CALCULATORS BY

[VI

HEWLETT PACKARD

HP-41C Calculator, "A System" .. $244.95 HP-32E Scientific w/Statistics ... $ 53.95 HP-33C Scientific Programmable ... 99.95 HP-34C Advanced Scientific

Programmable 123.95

HP-37E Business Calculator 58.95

HP-67 Handheld Fully Advanced

Programmable Scientific for

Business & Engineering 298.95

HP-97 Desktop w/Built-in Printer.. 579.95

COMMODORE PET Call for Prices

Prices do not include shipping by UPS. All prices and offers are subject to change without notice.

R

ersonal omputer ys terns

c

s

609 Butternut Street

Syracuse, N.Y. 13208

(315) 478-6800

'232 February 1981 © BYTE Publications Inc

Listing 1 continued:

034C C3DC01

JHP

034F 117706

I

NOFILE

LXI

0352 0E09

HVI

0354 CD0500

CALL

0357 C31E01

JHP

039C 039F 03A0 03A2 03A5 03A6 03A7 03A8 03A9 03AA 03AB 03AC 03AE 03B1 0363 03B6 03B7 03B8 03B9 03BA 03BB 03BC 03BP 03BE 03BF 03C0

110907

D5

0E0A

CD0500

AF

El

23

4E

23

47

7E

B630

FAC403

FE0A

B2C403

57

78

A7

17

5F

17

17

83

82

0D

C2A903

PRTHX ;GIVE DENSITY LIHITS.

D,NFHSG ;TELL USER THAT THIS FILE IS NOT

C,9 ;SAVED.

CPM

UHAT ;BACK TO OPTION LEVEL

SET THE TONE ARRAYS TO THE USER'S CHOICE. BOTH THE PRIMARY AND SECONDARY TONE ARRAYS HUST BE SET. EITHER ONE NAY BE BLANK.

035A 11B405 TSET LXI

D.MSG1

035D 0E09

HVI

C,9

035F CD0500

CALL

CPH

0362 110F07

LXI

D,INPUT1

;PUT THE STRING HERE

0365 0E0A

HVI

C,10

;USE CP/H'S LINE INPU

0367 CD0500

CALL

CPH

036A 110E06

LXI

D.HSG2

;ASK FOR SECONDARY AR

036D 0E09

HVI

C,9

036F CD0500

CALL

CPH

0372 115107

LXI

D,INPUT2

;PUT IT HERE

0375 0E0A

HVI

C, 1 0

0377 CD0500

CALL

CPH

037A C31E01

JHP

UHAT

,N0THING TO IT,

SECTION TO GET THE DESIRED HAXIHUH AND MINIMUM VALUES FR0H THE USER. THESE VALUES UILL REPLACE THOSE FOUND BY SCANNING THE DATA RECEIVED FR0H THE A/D. THIS UILL BE NECESSARY FOR THOSE CASES UHERE A PICTURE UAS BROKEN UP INTO H0RE THAN ONE IHAGE (DUE TO SIZE) AND A CONSISTENT SET OF CHARACTER SUBSTITUTIONS IS DESIRED.

037D 119F06 SETHAX LXI

D.SETHX

JTELL USER UHICH ONE TO TYPE.

0380 0E09

HVI

C,9

0382 CD0500

CALL

CPH

0385 CD9C03

CALL

GETNUH

;and get it.

0388 32D307

STA

HAX

;and save it.

038B 11D006

LXI

D.SETHN

;N0U DO THE SAHE FOR THE HIN VALUE

038E 0E09

HVI

C,9

0390 CD0500

CALL

CPH

0393 CD9C03

CALL

GETNUH

0396 32D407

STA

HIN

0399 C31E01

JHP

UHAT

;N0 CHECK IS HADE FOR LEGAL VALUES

ROUTINE TO READ IN A DECIHAL NUHBER TYPED BY THE USER. THE RESULTING VALUE IS RETURNED IN REGISTER (A). ALL REGISTERS ARE USED AND NOT RESTORED.

GETNUH

GETNH1

LXI

D,INBU

PUSH

B

HVI

C,10

CALL

CPH

XRA

A

POP

H

INX

H

HOV

C,H

INX

H

HOV

B,A

HOV

A,H

SUI

'0'

JH

BADNUH

CPI

10

JNC

BADNUH

HOV

D,A

HOV

A,B

ANA

A

RAL

HOV

E,A

RAL

RAL

ADD

E

ADD

D

DCR

C

JNZ

GETNH1

D.INBUFF JINPUT BUFFER TO USE

;use cp/h's input routine to allow corrections. clear the accuhulator. jpoint to buffer ;and skip over both counters ;get count anb save in (c>.

;save resulting value in (b) ;get a character ;hake binary

;legal?

jit's ok, save it here, jhultiply previous total by 10. jclear the carry flag.

;ADD IN NEU DIGIT. ;D0 ALL DIGITS.

Listing 1 continued on page 234

APPLE II ® TRS'80 <d

QUALITY DISK SOFTWARE

HOME FINANCE PAK I: Entire Series $49.95 ®£) ELECTRONICS SERIES: Entire Series $259.95 ®0

CHECK REGISTER AND BUDGET: This comprehensive CHECKING ACCOUNT MANAGEMENT SYSTEM not only keeps complete records, it also gives you the analysis and control tools you need to actively manage your account. The system provides routines for BUDGETING INCOME AND EXPENSE, AUTOMATIC CHECK SEARCH, and BANK STATEMENT RECONCILING. CRT or printer reports are produced for ACTUAL EXPENSE vs BUDGET, CHECK SEARCH DISPLAY, RECONCILIATION REPORT and CHECK REGISTER DISPLAY by month. Check entry is prompted by user-defined menus of standard purposes and recipient codes, speeding data entry and reducing disk storage and retrieval time. Six fields of data are stored for each check: amount, check no., date, purpose, recipient and TAX OEOUCTIBLE REMINDER. CHECK SEARCH routines allow searching on any of these data fields. Routines are also provided for CHECK SORT by date and check no., DATA EDITING and Report Formats. Up to 100 checks/mo. storage $39.95

SAVINGS: Account management system for up to 20 separate Savings accounts. Organizes, files and displays deposits, withdrawals and interest earned for each account. Complete records shown via CRT or printer $14.95

CREDIT CARD: Get Control of your credit cards with this program. Organizes, stores and displays purchases, payments and service charges for up to 20 separate cards. Use for credit cards or bank loans. CRT or printer reports $14.95

UNIVERSAL COMPUTING MACHINE: $49.95®®

A user programmable computing system structured around a 5 0 row x 50 column table. User defines row and column names and equations forming a unique computing machine. Table elements can be multiplied multiplied, divided, subtracted or added to any other element User can define repeated functionscommonto row or column greatly simplifying table setup. Hundreds of unique computing machines can be defined, used and stored, and recalled, with or without old data, for later use. Excellent for sales forecasts, engineering design analysis, budgets, inventory lists, income statements, production planning, project cost estimates in short for any planning, analysis or reporting problem that can by solved with a table. Unique curser commands allow you to move to any element, change its value and immediately see the effect on other table values. Entire table can be printed by machine pages (user-defined 3-5 columns) on a 40 column printer.

COLOR CALENDAR: $29.95®

Got a busy calendar? Organize it with Color Calendar. Whether it's birthdays, appointments, business meetings or a regular office schedule, this program is the perfect way to schedule your activities. The calendar display is a beautiful HI-RES color graphics calendar of the selected month with each scheduled day highlighted in color. Using the daily schedule, you can review any day of the month and schedule an event or activity in any one of 20 time slots from 8:00 A.M. to 5:30 P.M. Your description can be up to 20 characters long. The system will also print out hard copies on your minimum 40-column printer.

BUSINESS SOFTWARE: Entire Series $159.95 ®(D

MICROACCOUNTANT: The ideal accounting system for small businesses. Based on classic T-accounts and double-entry booking, this efficent program provides a ledger journal for recording, posting and reviewing up to 1,000 transactions per month to any one of 300 accounts. The program produces CRT and printer reports covering: Transaction Journal Balance Sheet Account Ledgers Income and Expense Statement Includes a short primer on Financial Accounting. Requires 48K Ram $49.95

UNIVERSAL BUSINESS MACHINE: This program is designed to

SIMPLIFY and SAVE TIME fai the serious businessman who must

periodically Analyze, Plan and Estimate. The program was created using

our Universal Computing Machine and it is programmed to provide the

following planning and forecasting tools.

CASH FLOW ANALYSIS SALES FORECASTER

PROFORMA PROFIT& LOSS SOURCE AND USE OF FUNDS

PROFORMA BALANCE SHEET JOB COST ESTIMATOR

REAL ESTATE INVESTMENT INVENTORY ANALYSIS

Price, including a copy of the Universal Computing Machine . . .$89.95

BUSINESS CHECK REGISTER AND BUDGET: Our Check Register and Budget programs expanded to include up to 50 budgetable items and up to 400 checks per month. Includes bank statement reconciling and automatic check search (48K) $49.95

LOGIC SIMULATOR: SAVE TIME AND MONEY. Simulate your digital logic circuits before you build them. CMOS, TTL, or whatever, if it's digital logic, this program can handle it. The program is an interactive, menu driven, full-fledged logic simulator capable of simulating the bit-time response of a logic network to user-specified input patterns. It will handle up to 1000 gates, including NANOS, NORS, INVERTERS, FLIP-FLOPS, SHIFT REGISTERS, COUNTERS and user-defined MACROS. Up to 40 user-defined random, or binary input patterns. Simulation results displayed on CRT or printer. Accepts network descriptions from keyboard or from LOGIC DESIGNER for simulation $159.95

LOGIC DESIGNER: Interactive HI-RES Graphics program for designing digital logic systems. A menu driven series of keyboard commands allows you to draw directly on the screen up to 15 different gate types, including 10 gate shape patterns supplied with the program and 5 reserved for user specification. Standard patterns supplied are NAND, NOR, INVERTER, EX-OR, T-FLOP, JK-FLOP, D-FLOP, RS-FLOP, 4 BIT COUNTER and N BIT SHIFT REGISTER. User interconnects gates just as you would normally draw using line graphics commands. Network descriptions for LOGIC SIMULATOR generated simultaneously with the CRT diagram being drawn $159,95

MANUAL AND DEMO DISK: Instruction Manual and demo disk illustrating capabilities of both programs $29.95

MATHEMATICS SERIES: Entire Series $49.95 ®

STATISTICAL ANALYSIS I: This menu driven program performs LINEAR REGRESSION analysis, determines the mean, standard deviation and plots the frequency distribution of user-supplied data sets. Printer, Disk, I/O routines $19.95

NUMERICAL ANALYSIS: HI-RES 2-Dimensional plot of any function. Automatic scaling. At your option, the program will plot the function, plot the INTEGRAL, plot the DERIVATIVE, determine the ROOTS, MAXIMA, MINIMA, INTEGRAL VALUE $19.95

MATRIX: A general purpose, menu driven program for determining the INVERSE and DETERMINANT of any matrix, as well as the SOLUTION to any set of SIMULTANEOUS LINEAR EQUATIONS. $19.95

3-D SURFACE PLOTTER: Explore the ELEGANCE and BEAUTY of MATHEMATICS by creating HI-RES PLOTS of 3-dimensional surfaces from any 3-variable equation. Disk save and recall routines for plots. Menu driven to vary surface parameters. Hidden line or transparent plotting $19.95

ACTION ADVENTURE GAMES: Entire Series $29.95 ®

RED BARON: Can you outfly the RED BARON? This fast action game simulates a machine-gun DOGFIGHT between your WORLD WAR I BIPLANE and the baron's. You can LOOP, DIVE, BANK or CLIMB-and so can the BARON. In HI-RES graphics $14,95

BATTLE OF MIDWAY: You are in command of the U.S.S. HORNETS' DIVE-BOMBER squadron. Your targets are the Aircraft carriers, Akagi, Soryu and Kaga. You must fly your way through ZEROS and AA FIRE to make your DIVE-BOMB run, In HI-RES graphics $14.95

SUB ATTACK: It.s April 1943. The enemy convoy is headed for the CORAL SEA. Your sub, the MORAY, has just sighted the CARRIERS and BATTLESHIPS' Easy pickings.But watch out for the DESTROYERS-they're fast and deadly. In HI-RES graphics $14.95

FREE CATALOG-AM programs are supplied on disk and run on Apple II w/Disk 8t Applesoft ROM Card & TRS-80 Level II and require 32K RAM unless otherwise noted. Detailed instructions included. Orders shipped within 5 days. Card users include card number. Add $1.50 postage and handling with each order. California residents add 6'/:% sales tax. Foreign orders add $5.00 postage and handling.

142 Carlow SPECTRUM P-O.Box 2084 SOFTWARE Sunnyvale, CA 94087

FOR PHONE ORDERS:(408)7384387

DEALER INQUIRIES INVITED.

Circle 158 on inquiry card.

BYTE February 1981 233

Circle 159 on inquiry card.

CTC-101 Terminals

we're overstocked on these powerful, reliable standard data terminals. The GT-101 is Z-80 based with standard printer port, user-settable clock, 8 user-programmable function keys and much more! Order Today! Limited Quantities.

Reg. S999.00 S7QC

Clearance Price Only / <j D

CTA ADC-16C

16 Channel variable

a-d Board!

can be used for Position/Pressure/Photoelectric/and Temperature Measurements, and as a computerized Volt/Ohm meter. Board is shipped with operating manual, software, and a test conducter. For use with Apple ll/lll. ._--,.

Introductory Price I /<j

NOTE: Soon To Be Available CTA's new 16K Memory Board!

CTA I

COMPUTER

TECHNOLOGY

ASSOCIATES

5812 cromo Drive, Suite 102

El Paso, Texas 79912

(915)581-3500

Visa/MasterCard/Diner's Club Accepted.

TO ORDER: Send check, money order or credit card number and exp. date to Computer Technology Associates, 5812 Cromo Drive, Suite 102. El Paso, Texas 79912. Personal or company checks require two weeks to clear, credit card users can call with card information.

shipping: we ship terminals prepaid by motor freight. Air and express delivery are available on all products.

There is no handling charge.

Listing 1 continued: 03C3 C9

03C4 11DD06

03C7 0E09

03C9 CD0500

03CC C39C03

03F3 0E09 03F5 CD0500 03F8 0E01 03FA C30500

RET |ALL DONE, RESULT IS IN (A).

BADNUM LXI D.BADINP ;TELL USER TO TRY AGAIN.

HVI C,9

CALL CPH

JHF GETNUH

READ THE A/D AND AVERAGE OVER EIGHT READS TO REDUCE THE SCATTER THAT IS BOUND TO EXIST UITH THIS SIMPLE IMAGE PROCESSING SYSTEM.

03CF

E5

READ

PUSH

H

03D0

C5

PUSH

B

03D1

210000

LXI

H,0

;KEEP SUM HERE

03D4

0608

HVI

B,8

03D6

CD1604

RLP1

CALL

AT0D

|READ THE A/D

03D9

85

ADD

L

;add VALUE TO OUR sum

03DA

6F

NOV

L,A

03DE

3E00

HVI

A,0

03DD

BC

ADC

H

03DE

67

MOV

H,A

03DF

05

DCR

B

03E0

C2D603

JNZ

RLPt

03E3

0603

MVI

B,3

;nou divide by s

03E5

A7

RLP2

ANA

A

;CLEAR CARRY

03E6

7C

MOV ■

A,H

03E7

1F

RAR

03E8

67

MOV

H,A

03E9

7D

MOV

A,L

03EA

IF

RAR

03EB

6F

MOV

L,A

03EC

05

DCR

B

D3ED

C2E503

JNZ

RLP2

03F0

C1

POP

B

03F1

El

POP

H

03F2

C9

;

RET JTILITY

ROUTINES..

ASK A MESSAGE POINTED TO BY (DE), AND GET A ONE CHARACTER RESPONCE. THE RESP0NCE IS RETURNED IN (A). ALL REGISTERS ARE USED AND NOT RESTORED.

ASK

MVI C,9

CALL CPM

MVI C,1

JMP CPM

JPRINT MESSAGE AND GET RESPONCE

CHECK THE KEYBOARD TO SEE IF ANYTHING IS READY. ON SYSTEMS THAT LATCH THE OUTPUT FROM THE TERMINAL, THE USER JUST HITS A KEY AND THEN THIS UILL DETECT IT. ON OTHER TYPES (LIKE MINE), THE USER MUST HOLD THE KEY DOUN UNTIL THIS ROUTINE IS CALLED. A MINOR INCONVENIENCE. ALL REGISTERS EXCEPT (A) ARE SAVED. IF A KEY IS TYPED, THEN THIS UILL RETURN UITH THE CARRY FLAG SET.

;CHECK THE KEYBOARD FOR ANYTHING

03FD C5 CHECK PUSH

B

03FE E5

PUSH

H

03FF D5

PUSH

D

0400 OEOB

MVI

C, 11

0402 CD0500

CALL

CPM

0405 Dl

POP

D

0406 El

POP

H

0407 CI

POP

B

0408 IF

RAR

0409 C9

RET

SEND ONE CHARACTER TO THE LIST DEVICE. THE CHARACTER MUST BE IN REGISTER (E) AND ALL REGISERS (EXCEPT A) ARE SAVED.

Listing 1 continued on page 236

040A C5

PRINT

PUSH

B

JPRINT (E)

040B E5

PUSH

H

040C D5

PUSH

D

040D 0E05

MVI

C,5

040F CD0500

CALL

CPM

234 February 1981 © BYTE Publications Inc

"WITH THE UCSD p-SYSTEM,™ WE CAN WRITE ONE APPLICATION THAT GOES FROM APPLE TO ZENITH?

HARRY BLAKESLEE, President, Denver Software

UCSD p-System and UCSD Pascal are trademarks of the Regents of the University of California.

Our business is bigger and better than ever. A lot of the credit for that goes to the UCSD p-System software from SofTech Microsystems. It's given us ten times the market we used to have.

We can write a single, sophisticated applications program with the UCSD p-System — like our financial management package—and it just keeps on running. On Apple, Commodore, Ohio Scientific, Texas Instruments, Zenith, and more. That's the real beauty of the UCSD p-System. Any program you write for one microcomputer runs on others, both today and tomorrow. You protect your software investment, without restricting your hardware options.

And with the UCSD p-System,you can use the language of your choice —UCSD Pascal,™ FORTRAN-77, BASIC, or assembly language. All are backed by SofTech Microsystems, a leading system software company who's been around for over a decade, who knows how to develop professional quality software, and who's committed to delivering it.

Get a head start on tomorrow. With the microcomputer software that goes from "A" to "Z." Distribution licensing and single copies available. Write or call for details, so you can start going places, too.

micRosvsTems

Ft SUBSOWIV OF SOFTECH

For the software that's going places.

9494 Black Mountain Road, San Diego,

CA 92126. (714) 578-6105

TWX: 910-335-1594

Circle 160 on inquiry card.

BYTE February 1981

235

Circle 161 on inquiry card.

Buy By Mail and Save!

INTERTECSuperBank, 32K .$2495

64K Ram, List $3345 $2695

64K Quad, List $3995 $3395

NORTH STAR Horizon I

32K DD List $2695 $1989

Horizon I QD List $2995 $2245

Horizon 2 32K DD.List $3095 $2289

lntersystemDP-1 List $1749 . .$1495

t

CROMENCO Z-2, List $9995 .$7945

System 64K, List $3990 $3179

System 3 64K, List $7395 5689

ATARI 800, List $1080 $799

APPLE II, 16K $969

DISK SYSTEMS

THINKER TOYS" Discus 2D ..$939

Dual Discus 2D $1559

Discus 2+ 2, List $1549 $1259

M26 Hard Disk, List $4995 .. .$3949

PRINTERS & TERMINALS

PAPER TIGERS IDS-440 $679

With graphic option $749

CENTRONICS 730-1,List $795 $595

737, List $995 $789

704-9 180 cps $1495

703-9 180 cps $1569

T I 810,List S1895 $1489

NECSPINWRITER5530 $2395

NEC SPINWRITER 5515 $2395

DIABLO 630 List $2711 $2399

INTERTEC

Intertube III.List $895 729

Emulator $729

Televldeo 912C $679

920C $799

Hazeltine1420 $789

1500 $845

Soroc 120, List $995 $689

Soroc140 $994

Most items in stock for immediate delivery. Factory sealed cartons, w/toll factory warranty. NYS residents add appropriate sales tax. Prices do not include shipping. VISA and Master Charge add 3%. C.O.D. orders require 25% deposit. Prices subject to change without notice.

Computers Wholesale

P.O. Box 144 Camillus, NY 13031 S. (315)472-2582

Listing 1

conti

tued:

0412 D1

POP

D

0413 El

POP

H

0414 C1

POP

B

0415 C9

RET

READ THE A/D. IT IS ASSUHED HERE THAT THE SETUP IS SIMILAR TO THAT PROPOSED IN DDJ, OCTOBER 1979. HERE, THE H/A IS CONNECTED TO OUTPUT PORT 2, AND THE RESULT OF THE COMPARITOR IS READ FROH INPUT PORT 2, BIT 0. FOR THE DIGITAL GROUP SYSTEN, THE INPUT DATA UILL BE INVERTED BY THE CPU CARD. IF YOURS DOES NOT UCRK THIS UAY, CHANGE THE 'JNZ' TO A 'JZ' IN THE CODE BELOU. THE RESULTING VALUE IS RETURNED IN IA) AND ALL OTHER REGISTERS ARE SAVED. THIS PROCEDURE USES A BINARY SEARCH TECHNIQUE TO FIND THE VALUE OF THE VOLTAGE INPUT TO THE A/D.

0416

C5

ATOD

PUSH

B

;READ A/D (.34 MS PER READ AVERAGE)

0417

AF

XRA

A

;READ THE A/D

0418

0680

HVI

6,128

041A

0E08

HVI

C,8

041C

80

ADLOOP

ADD

B

;SET THE D/A

041D

D302

OUT

2

041F

F5

PUSH

PSU

0420

DB02

IN

2

;READ AND CHECK BIT DO

0422

E601

ANI

1

0424

C22A04

JNZ

ADI

;*** SYSTEM DEPENDENT **»

0427

F1

POP

PSU

0428

90

SUB

B

;T00 FAR, BACK OFF

0429

F5

PUSH

PSU

042A

78

ADI

MOV

A,B

;next BIT

042B

1F

RAR

042C

47

MOV

B,A

042D

Fl

POP

PSU

042E

OD

DCR

C

;D0 ALL 8 BITS

042F

C21C04

JNZ

ADLOOP

0432

CI

POP.

B

0433

C9

RET

BINARY TO ASCII ROUTINE

THIS ROUTINE UILL CONVERT A 16 BIT BINARY NUMBER INTO ASCII ACCORDING TO A SPECIFIED RADIX VALUE. THE DIGITS USED ARE: 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F,G,H,I,J,K ETC

TO USE:

HL=ADDRESS OF A BUFFER FOR THE RESULTING ASCII DIGITS

DE=CONTAINS THE 16 BIT NUMBER TO CONVERT

B =THE NAXIMUM LENGTH OF THE BUFFER

C =THE RADIX TO USE (2,8,16,...ETC)

ON RETURN, THE CARRY FLAG IS SET IF AN OVER-FLOU OCCURED (BUFFER UAS TOO SHALL).

0434

3E30

BTOA

HVI

A,'0'

JADJUST THE RADIX FOR ASCII CONVERSION

0436

81

ADD

C

0437

FE3B

CPI

'9' + 2

0439

DA3E04

JC

BT0A1

043C

C607

ADI

7

043E

4F

BT0A1

MOV

C,A

; BLANK

OUT THE BUFFER

SPACE

043F

78

MOV

A,B

0440

3620

BT0A2

MVI

■V '

0442

23

INX

H

0443

3D

DCR

A

0444

C24004

JNZ

BT0A2

0447

2B

DCX

H

; CONVERT THE

NUMBER NOU.

0448

3630

MVI

N,'0'

|ZER0 OUT THE FIRST DIGIT.

044A

7A

MOV

A,D

JCHECK FOR ZERO

044B

B3

ORA

E

044C

C8

RZ

044D

34

INR

M

Listing 1 continued on page

KIM AIM

ANALOG INTERFACES

Industrial, Scientific, Laboratory, or Commercial Microcomputer Usersindustrial quality data conversion boards are available for APPLE, S-100, PET, TRS-80, AIM, and KIM systems. Tecmar can provide individual boards, data conversion subsystems, or complete Data Conversion Systems. Tecmar's growing productline offers outstanding features, meticulous engineering, exceptional documentation, and a seven year record of proven reliability.

TRS-80

Tecmar's new Analog to Digital Converter Series (AD-200) is designed to meet sophisticated data acquisition needs. The board accommodates various precision A/D modules made by Analogic and Data Translation. These modules are easily interchanged to provide options such as 12, 14, or 16 bit accuracy; 125 KHz throughput; variable ranges and gains. AD212 S-100 A/D and Timer Board $695

AD211 Apple A/D Board $495

AD-200 Features

• 12 bit accuracy and resolution standard

• 30 KHz conversion rate standard

• 16 single-ended or 8 true differential inputs • jumper selectable

• External trigger of A/D

• Output formats: Two's complement, binary, offset binary

• Auto channel incrementing from any channel to any channel

• Data is latched providing pipelining for higher throughputs

• Provision for synchronizing A/Ds

• Utilizes interrupt or status test

• Jumper selectable input ranges: ±10V, ±5V, Oto+lOV, Oto +5V In addition the S-l 00 version:

• Complies with IEEE S-100 specifications

• Transfers data in 8 or 16 bit words

• Provides for expansion to 256 channels

• Is switch selectable I/O or memory mapped

Timer Features on S-100 Board

In addition to the A/D features, the S-100 Board contains a powerful timer circuit which can start A/D conversion and can also be used independently for time of day, event counting, frequency shift keying and many other applications.

• 5 independent 16 bit counters (cascadable)

• 15 lines available for external use

• Time of day

• Event counter

• Alarm comparators on 2 counters

• One shot or continuous frequency

• Complex duty cycle and frequency shift keying outputs

• Programmable gating and count source selection

• Utilizes vectored interrupt

outputs

Options for AD-200

Programmable gain up to 500

14 bit accuracy

1 6 bit accuracy

100 KHz conversion rate

125 KHz conversion rate

Screw Terminal and Signal Conditioning panel

• Thermocouple cold junction compensation

• Rack mounting assembly with plexiglass cover Low level, wide range permitting low level sensors such as thermocouples, pressure sensors and strain gauges to be directly connected to the module input

$

175 717 1,117 517 617 250 125 125 70

TRS-80

Apple D/A Features $295

12 bit accuracy and resolution

2 independent digital to analog converters

8 parallel latched output lines

Jumper selectable output ranges: ±10V, ±5V, ±2.5V,

Oto+lOV, Oto +5V

• 3 microsecond conversion time

• Minimal software required

• Optional 4-20 mA board available

S-100 PET2 TRS-801

The original Tecmar data conversion boards (AD-100 and DAT 00) continue to solve less sophisticated conversion problems. These S-l 00 boards interface to the PET, TRS-80, AIM, and KIM through S-100 expansion interfaces.

AD-100 Features $495

AIM3 KIM2

12 bit accuracy and

resolution

30 KHz conversion rate

16 single-ended or 8 true

differential inputs (specify

AD-100SorAD-100D)

Minimal software required

I/O or memory mapped operation for S-100 systems - jumper selectable Jumper selectable input ranges:+10V.+5V, Oto +10V, 0to+5V IEEE S-100

DA-100 Features $395

• 12 bit accuracy and resolution

• 4 independent digital to analog converters

• 3 microsecond settling time

• Jumper selectable output ranges:+10V, ±5V, +2.5V,

Oto +10V,0to+5V

• I/O or memory mapped operation for S-100 systems - jumper selectable

• Minimal software required

• IEEE S-100

• Optional 4-20 mA board available Expansion board, power supply, and enclosure for PET * 250 Expansion board and power supply for TRS-80, KIM, or AIM 150

S-100 Real Time Video Digitizer

Digitizes and Displays in 1/60 sec, flicker-free 16 Gray Levels Switch Selectable to display Black and White Graphics (8 pixels/byte) Maximum Resolution: 512 pixels/line x 240 lines Minimal software requirements $850

EC

RR

INC.

Data Acquisition Systems and Video Digitization Systems Available

23414 Greenlawn • Cleveland, OH 44122

S-l 00 BOARDS

8086 CPU $450

W/vectored interrupts

RAM $395

8Kxl6/16Kx8

8086 $495

PROM-I/O

Serial and $350

Parallel I/O

Parallel I/O $350

& Timer

'Reg. Tiademarto of Tandy Corp. 2Reg. Tiademaik of Commodore JReg. Tiademaito of Rockwell

TECMAR, INC.

(216)382-7599

Circle 162 on inquiry card.

Circle 163 on Inquiry card.

Are your users saying . . .

"@#* It should be here, but where?!"

How much valuable time is wasted searching for items which should have been indexed?

At Last, Indexing for WordStar™

DocuMate™ from the Orthocode Corporation solves this annoying problem.

DocuMate™ features

■ Table of Contents Generation

■ Multi-level Indexing

■ See and See also references

DocuMate can make a table of contents automatically from any Wordstar text file. In conjunction with a sort utility such as Supersort™ it can also generate alphabetized, multi-level sorted indexes.

Just put simple DocuMate commands in your text file; DocuMate does the rest. DocuMate commands look like comments to WordStar; they have no effect on your printed output.

If you publish computer manuals or other documentation, nothing will give them that professional look like a good index.

DocuMate is available now on standard 8" CP/M™ diskettes.

■ Manual only - $5.

■ CP/M version - $50.

Add $4 for shipping & handling

>5fflH®C0DE

The Textware Company

THE ORTHOCODE CORPORATION

P.O. Box 6191

Albany, California 94706

Phone (415) 527-9300

TWX 910 366-7046

WORDSTAR &SUPERSORT ARE TRADEMARKS OF

MICROPRO INTERNATIONAL

CP'M IS A TRADEMARK OF DIGITAL RESEARCH.

238 February 1981 © BYTE Publications Inc

I

Listing 1 continued:

044E IB BLP OCX

044F 7B HOv

0450 B2 ORA

0451 CB RZ

B

A,E

B

;roll boun counter |is it zero yet ?

;yes then ue are bone, roll up the result in odometer fashion

0452 E5

0453 C5

0454 7E

0455 3C

0456 B9

0457 C26C04 045A 3630 045C 2B 045D 05 045E CA7504

0461 7E

0462 FE20 0464 C25404 0467 3630 046? C35404 046C 77 046D FE3A 046F C27504 0472 C607 0474 77

0475 CI

0476 E1

0477 C24E04 047A. 37 047B C9

BT0A3

BT0A4

PUSH

PUSH

MOV

INR

CHP

JNZ

MVI

BCX

DCR

JZ

HOV

CPI

JNZ

NVI

JHP

MOV

CPI

JNZ

ABI

MOV

H

B

A,M

A

C

BT0A4

M, 0'

H

B

BT0A5

A,M

JT0A3 H, '0' BT0A3 M,A "9' + 1 BT0A5

M,A

JKEEP REGS

JREACHEI RABIX LIMIT ?

JYES, RESET THIS BIGIT TO ZERO ANB U0RK JON THE NEXT (IF THERE IS ONE).

JOVER-FLOU

;CHANGE A BLANK INTO A ZERO FIRST TIME HERE

jCHECK FOR A BIGIT >? ANB BUMP PAST SOME JASCII JUNK

RESTORE THE REGS AND CONTINUE UNLESS THE ZERO FLAG IS SET.

BT0AS

POP POP JNZ STC RET

B H BLP

|SET THE CARRY ON AN 0VER-FL0U ERROR

MESSAGE AREA

047C 049E 04 B 5 04BF 04B0 04E7 050B 0528 0543 0557 056A 0560 0561 059F 05B8 05D4 05FC 060E 061B 062E 064A 065A 065F 0677 069F 06C3 06D0 06DD 0702

0D0A494D41HELL0

2020207665

0D0A4B656E0PTI0N

463B46696C

483D48656C

4B3B536574

503B507269

513B517569

523D526561

533B536361

543B536574

24

0B0A4F7074QUESTN

0B0A506F73P0S

0B0A446973ERR1

0B0A456E74MSG1

3C7265743E

0B0A536563MSG2

0D0A4C696ELLNGTH

0D0A496B61MAXMIN

3030302C20MAXV

3030302E24MINV

0D0A4E6F20N0NE

0B0A4E6F20NFMSG

0B0A536574SETMX

0B0A4B6178

0B0A4B696ESETMN

0B0A4F6E6CBABINP

0B0A3F2024

BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB BB

10,'"IMAGE Inage Processing Progran' ver 2.00 11-05-79*' 10,'Henue:',13,10 File the data',13,10 Help, display nenue■ ,13,10 Set the naxinun and hininim values',13,10 Print the data back out',13,10 Quit and return to CP/M', 13,10 Read the file in',13,10 Scan a new page',13,10 Set the tone array',13,10

10,'

10,'

10,'

10,'

et>'

10,'

10,'

10,'

0, n

0.*'

10,

10,'

10,'

10,'

10,'

10,'

10,'

Option (F,H,M,P,Q,R,S,T) ? $'

Position paper (space)*'

Disk or directory is full*'

Enter density characters (nax to Kin),"

,13,10,'Prihary -?*'

Secondary -?*'

Line length -?*'

Inage scanned: Max value ='

in value ='

No inage was scanned.*'

No scan data was saved for this file.*'

Setting naxinuK and nininun values'

MaKinuh ? *'

Minimin 1 *'

Only digits 0-9 are allowed, retry."

? *'

BATA STORAGE AREA

0707 00 SCALE BB

0708 00 NSECT BB

0709 0400000000INBUFF BB 070F 40 INPUT1 BB

0710 1E NUNBR1 DB

0

0 JSECTORS USED IN SCAN

4,0,0,0,0,0 JNUMERIC INPUT BUFFER

64 JMAX LENGTH OF FRIMARY TONE ARRAY

30 JCURRENT LENGTH

Listing 1 continued on page 240

Aflft ^B ^P Licenced I>t Sinclair Research Lid

Microcomputer

for everyone at a Micro Price

The LMicrofkel

The unique

and valuable

components of the MicroAce

The MicroAce is not just another personal computer. Quite apart from its exceptionally low price, the MicroAce has two uniquely advanced components: the powerful BASIC interpreter, and the simple teach yourself BASIC manual.

The unique versatile BASIC interpreter offers remarkable programming advantages:

• Unique 'one-touch' key word entry: the MicroAce eliminates a great deal of tiresome typing. Key words (RUN, PRINT, LIST, etc.) have their own single-key entry.

• Unique syntax check. Only lines with correct syntax are accepted into programs. A cursor identifies errors immediately. This prevents entry of long and complicated programs with faults only discovered when you try to run them.

• Excellent string-handling capability - takes up to 26 string variables of any length. All strings can undergo all relational tests (e.g. comparison). The MicroAce also has string input to request a line of text when necessary. Strings do not need to be dimensioned.

• Up to 26 single dimension arrays.

• FOR/NEXT loops nested up 26.

• Variable names of any length.

• BASIC language also handles full Boolean arithmetic, conditional expressions, etc.

• Exceptionally powerful edit facilities, allows modification of existing program lines.

• Randomise function, useful for games and secret codes, as well as more serious applications

• Timer under program control.

PEEK and POKE enable entry of machine code instructions, USR causes jump to a user's machine language sub-routine.

• High-resolution graphics with 22 standard graphic symbols.

• All characters printable in reverse under program control.

• Lines of unlimited length.

'Excellent value' indeed!

For just $149.00 (including handling charge)you get everything you need to build a personal computer at home.., PCB, with IC sockets for all ICs; case; leads for direct connection to a cassette recorder and television (black and white or color); everything!

Yet the MicroAce really is a complete, powerful, full-facility computer, matching or surpassing other personal computers at several times the price.

The MicroAce is programmed in BASIC, and you can use it to do quite literally anything, from playing chess to managing a business.

The MicroAce is pleasantly straightforward to assemble, using a fine tipped soldering iron. It immediately proves what a good job you've done: connect it to your TV ... link it to the mains adaptor ... and you're ready to go.

Fewer chips, compact design, volume production-more power per Dollar!

The MicroAce owes its remarkable low price to its remarkable design: the whole system is packed on to fewer, newer, more powerful and advanced LSI chips. A single SUPER ROM, for instance, contains the BASIC interpreter, the character set, operating system, and monitor. And the MicroAce 1K byte

- a new generation of miniature computers

A COMPLETE COMPUTER for $149.00 for 1K Kit

Post and Packing FREE

(Add 6% Tax for Shipments inside California)

RAM (expandable to 2K on board) is roughly equivalent to 4K bytes in a conventional computer typically storing 100 lines of BASIC. (Key words occupy only a single byte.)

The display shows 32 characters by 24 lines.

And Benchmark tests show that the MicroAce is faster than all other personal computers.

No other personal computer offers this unique combination of high capability and low price.

The MicroAce teach-yourself BASIC manual.

If the features of the BASIC interpreter mean little to you-don't worry. They're all explained in the specially-written book free with every kit! The book makes learning easy, exciting and enjoyable, and represents a complete course in BASIC programming-from first principles to complex programs. (Available separately-purchase price refunded if you buy a MicroAce later.) A hardware manual is also included with every kit.

The MicroAce Kit:

$149.00 with IK COMPLETE

$169.00 with 2K

Demand for the MicroAce is very high: use the coupon to order today for the earliest possible delivery. All orders will be despatched in strict rotation. If you are unsuccessful in constructing your kit, we will repair it for a fee of $20.00, post and packing FREE. Of course, you may return your MicroAce as received within 14 days for a full refund. We want you to be satisfied beyond all doubt and we have no doubt that you will be.

280 A microprocessor chip, widely recognised as ihe best ever marie.

■■■■■■■■■a ■■■■■■■«■■ BiiiiiiiiBi;

Your MicroAce kit contains...

• Printed circuit board, with IC sockets for all ICs. Complete components set, including all ICs-all manufactured by selected world-leading suppliers. New rugged keyboard, touch-sensitive, wipe-clean. Ready-moulded case. Leads and plugs for connection to domestic TV and cassette recorder. (Programs can be SAVEd and LOADed on to a portable cassette recorder.) Mains adaptor of 600 mA at 9VDC nominal unregulated. FREE course in BASIC programming and user manual.

JOIN THE REVOLUTION - DON'T GET LEFT BEHIND - ORDER YOUR MICROACE NOW!!

Send Check, Money Order or quote your Credit Card No. to: MicroAce 1348 East Edinger, Santa Ana, California, Zip Code 92705. or phone (714} 547 2526 quoting your Credit Card Number.

Quantity

Description

Unit Price

MicroAce Kit 1K

$149.00

MicroAce Kit 2K

$169.00

Manual

$10.00

1K Upgrade Kit

$29.00

Shipmen add 6%

Is inside California TAX

TOTAL

Amex. Diners Check

Money Order Master Charge Visa

Card No..

Exp. Date

Name.

AddressCity

.Zip.

Circle 164 on inquiry card.

BYTE February 1981 239

Text continued from page 222:

collected onto the file specified in the initial command "filename". If this file already exists, it will be deleted. This allows the user to keep the basic data for processing at a later time. When completed, the user is returned to the option-selection level. Two possible errors may occur here:

• "Disk or directory full". This means that you don't have enough room on the current disk to save all the data. Sorry, you will have to start over. Note that the storage space required is 1 byte per column per line.

• "No image was scanned". Here, you must scan an image before trying to file the data.

H: Help Me

The user can type H to view the whole menu again. Normally only the "option" line is printed.

M: Set the Maximum and Minimum Values

This option allows the user to specify what values are to be used in place of the actual maximum and minimum values in the data array. This is necessary when you want to print two separate pictures with the same character-substitution sequence. (For example, this is the case when, due to its size, a picture was broken up into two or more sections.) The numbers are entered as decimal numerals in the range 0 to 255. If the data is filed after making this change, the new maximum and minimum values will be permanent.

P: Print the Data

When you are ready to print the image, with the charactersubstitution array set and an image scanned, this option will give you time to change the paper and position the carriage by issuing the following message:

Position paper (space)

Hit the space bar when ready to begin. The program scales all of the light intensity levels stored so that the picture fits the length of charactersubstitution array entered. (Both the primary and secondary arrays are treated separately.) To terminate the printed listing prior to the actual end of the data, type any key. You are returned to the option-selection level.

Listing 1 continued:

0711 4045252423T0NE1

DB

'eEZ«lt;1*HI!7AXItN8»032I7*+(!',39,'-'

,39,' '

072F

DS

34

0751 40 INPUT2

DB

64 SECONDARY TONE ARRAY

0752 1E NUHBR2

DB

30 JITS CURRENT LENGTH

0753 2323232323T0NE2

DB

'HRHMMMI!!!!! ',39,'

/

0771

DS

34

0793

DS

&4 ;STACK AREA

07D3 = STACK

EQU

«

07D3 00

MAX

DB

0

07D4 00

HIN

DB

0

07D5 00

LNGTH

DB

0

07D6 00

LINES

DB

0

07D7 =

BUFF

EQU

t

THE F0LL0UING DATA IS SAVED ON THE FILE.

;haxihuh value in array ;hinihun value ;line length jnuhber of lines ;start data array here.

0005 =

CPU

EQU

;ENTRY to the system.

07D7

END

100H

042A AD1

041C

ADL00P

03F3

ASK

0416

AT0D

06DD

BADINP

03C4 BADNUH

044E

BLP

0434

BT0A

043E

BT0A1

0440

BT0A2

0454 BT0A3

046C

BT0A4

0475

BT0A5

07D7

BUFF

03FD

CHECK

0005 CPM

018C

D01

0197

D02

01A5

D03

0261

11

0283 D2

028A

D3

01C2

DELAY

0259

DIVLP

027B

DIVLP1

02C6 ERR

05B8

ERRI

02D1

F1

02A3

FILE

02DB

FILELP

03A9 GETNM1

039C

GETNUH

047C

HELLO

0100

IHAGE

0709

INBUFF

017D INLP

026D

INLP1

070F

INPUT)

0751

INPUT2

07D6

LINES

061D LLNGTH

07D5

LNGTH

07D3

MAX

062E

MAXHIN

064A

MAXV

07D4 HIN

065A

HINV

05D4

HSGI

060E

HSG2

0677

NFMSG

034F N0FILE

065F

NONE

0304

NOTHING

0708

NSECT

0710

NUHBR1

0752 NUHBR2

0116

OPT

04B5

OPTION

0179

0UTLP

0269

0UTLP1

059F POS

0245

POUT

040A

PRINT

024E

PRINTLN

0205

PRT

0212 PRTLP

01DC

PRTHX

0581

QUESTN

0340

READDN

030F

READF

03CF READ

0322

READLP

03D6

RLP1

03E5

RLP2

0707

SCALE

014C SCAN

037D

SETHAX

06D0

SETHN

069F

SETMX

07D3

STACK

0711 TONE)

0753

T0NE2

01CF

TOUT

035A

TSET

011E

UHAT

w • cm

MM*

co mi \

s o * IN

— n» ■» CM —

• na»Hn

■ nooniN

ro co •» w rs.

+ m rs \ i

+ «• f~> \ * 4

— 00 Pv s «• <

CM GO CM M GO (

-HN I — M CO

+ co \— — # — \ + t*y m t

— CO +#%—*. I w © *> 4

— •> — ps. — — i \ — © m t

\ CO— rO©i-»CNrNCN*»M»«

— co * (N<*nnN»oo»tti * co P9 No«ococo«t)«»i

I !•>■¥»■*» K »•.»•■» <

p*> oo *

won DMn

OOONCO I »00)H(D •

■o CM t— I

CO CO M * I * •

— CM CM * I

— CO M Pv

IMHIBN • l*H(DNn\

. o co ** o ro \ ■ oo«nN i

+ r>. ro en m* m, ■

+ -■ >-< o m> r-« ■■ w

\ \ + ora*Ha

■ Nm- » CM «k •» «» «

• ONnnwomoi

■ » © CO —

—■ h* to \

■ «■* r*» o

* PO GO H* Pv fO ~' ■

• NMNOWI

» » r-j ro ro o •

i CO CO

' © *> • Pv Pv

■ Pv »■♦■— — i s \

■ W M N + '

i oa cd »o n nn

> » o-j ** .

l»«(Di

© © po

© ro © \

© © PO

' N«ffiOO<

» CM © CO CO I

I * ro «* «• co »-• O ■

\ + ro co o co P-t *► l

*- » » \ o co 10 co co co i

— rv cm * «no«Hni

I Nnn*NocoH«»'

' n to « to cbi

ro co <=> co i* t

i © co m %•> co <

, « r\ * m n co I

• • * PN. PO

i «-■ cm © o

IPJPIO o INMOO •

© CO © CO

I CO CO «» CO

iNNNMI

O CO CO CO 4* (

ipionn*eoM*ococo(

i cm m n po «

240 February 1981 © BYTE Publications Inc

yum/u.

M1CR0PR0CE5S0R

INTERFACE TECHNIQUES

i

r ly^Tnrnt.

BUY ONE ofthese great professional books and

ET ONE FREE

(values up to $60.00)

when you join the COMPUTER I PROFESSIONALS' BOOK CLUB

Choose any one of these books at the special club discount, and select any other as your gift Free of Charge when you enroll:

MICROPROCESSOR PROGRAMMING AND SOFTWARE DEVELOPMENT By F. G. Duncan 582069-2 Pub. Pr., $28.00 Club Pr„ $21.50

BIT-SLICE MICROPROCESSING DESIGN By J

Mick & J. Brick 417/814

Pub. Pr, $18.50

Club Pr.,514.50

COMPUTER DICTIONARY AND HANDBOOK,

3/e By C. J. Sippl

582079-X Pub. Pr., $29.95 Club Pr., $24.95

ELECTRONICS DICTIONARY By J Markus 404/313 Pub. Pr., $24.50 Club Pr, $19.50

MICROCOMPUTER INTERFACING By B. Artwick 789/436 Pub. Pr., $21.95 Club Pr„ $16.95

SOFTWARE DEBUGGING FOR MICROCOMPUTERS R y R Bruce

582075-7 Pub. Pr., $18.95 Club Pr„ $14.25

ENCYCLOPEDIA OF COMPUTER SCIENCE

EditedbyA. Ralslon & C. L. Meek

769/01X Pub. Pr„ $60.00 Club Pr., $39.95

AUTOMATIC DATA PROCESSING HANDBOOK

Edited by The Diebold Group, Inc.

168/075 Pub. Pr., $44.95 Club Pr., $31.50

PROGRAMMING LANGUAGES BY A B Tucker. Jr. 654/158 Pub. Pr, $23.95 Club Pr., $16.95

MICROPROCESSOR APPLICATIONS MANUAL

By Motorola. Inc.

435/278 Pub. Pr., $42.50 Club Pr., $29.50

DATA BASE DESIGN By G. Wiederhold 701/30X Pub. Pr., $25.95 Club Pr„ $19.95

PRINCIPLES OF INTERACTIVE COMPUTER GRAPHICS, 2nd Ed. By W. M. Newman & R F. Sproull 463/387 Pub. Pr., $26.95 Club Pr., $20.95

MICROPROCESSOR INTERFACING TECHNIQUES, 3/e By R. Zaks & A. Lesea 582050-1 Pub. Pr., $25.00 Club Pr., $19.95

THE GIANT HANDBOOK OF COMPUTER PROJECTS By the Editors of 73 Magazine 582012-9 Pub. Pr., $15.95 Club Pr., $13.50

PROGRAMMING THE 6502 By R Zaks 582048-X Pub. Pr, $12.95 Club Pr., $10.95

SOFTWARE ENGINEERING By R. W Jensen & C. C. Tonies 788/367 Pub. Pr., $27.50 Club Pr, $19.95

PROGRAMMING THE ZBO By R Zaks

582049-8 Pub. Pr, $14.95 Club Pr., $12.70

HANDBOOK OF OPERATIONAL AMPLIFIER CIRCUIT DESIGN By D. F Stout, edited by M. Kaufman 617/97X Pub. Pr, $29.95 Club Pr, $17.50

Why YOU should join now!

• BEST BOOKS IN YOUR FIELD —Books are selected from a wide range of publishers by expert editors and consultants to give you continuing access to the latest books in your field.

• BIG SAVINGS—Build your library andsavemoney too! We guarantee savings of at least 15% off publishers' list prices on every book. Usually 20%, 25% or even higher!

• BONUS BOOKS—You will immediately begin to participate in our Bonus Book Plan that allows you savings between 70-80% off the publisher's price of many books.

• CONVENIENCE —14 times a year you receive the Club Bulletin FREE, fully describing the Main Selection and alternate selections, together with a dated reply card. If you want the Main Selection, you simply do nothing —it will be shipped automatically. If you want an alternate selection —or no book at all —you simply indicate it on the regular reply card and return it by the date specified. You will have at least 10 days to decide. If, because of late mail delivery of the Bulletin you should receive a book you do not want, just return it at the Club's expense.

As a Club member, you agree only to the purchase of four books (including your first selection) over a two-year period.

McGraw-Hill Book Clubs

COMPUTER PROFESSIONALS' BOOK CLUB

RO. Box 582. Hightstown. New Jersey 08520

Please enroll me as a member and send me the two books indicated, billing me for mytirst selection only al the discounted member's price, plus local tax, postage and handling. If nol satisfied, I may return the books within 10 days ond my membership will be canceled. I agree lo purchase a minimum of 3 additional books during the next 2 years as outlined under the club plan described in this ad. Membership in the club Is conlinuous but cancellable by me any time offer the four book purchase requirement has been fulfilled.

Write Code # of FREE selection here

Write Code # of FIRST selection here

Orders from outside the U.S. must be prepaid with international money orders in U.S

dollars.

Charge my a VISA a MASTER CHARGE* Exp. Dole

Credil Card # 'MCBonk*

Signature

Name

Address

City, Stole. Zip

Corporate Affiliation

This order subject to acceptance by McGraw-Hill. All prices subject to change without notice. Offer good only to new members. A postage ond handling charge is added to oil shipments. P3948B

IttVIVfRfVPI*

mbbbbbbmbmbmbbmbmbmmmbmbmmmbbbb

tBBBBBBBHj«k»«aBMB»-iMBMBBBfN. +■ IN O * < iMBMMMMBOtvtMBMBi-tMMMCMr^i-iroeOC IBBanBa«B*»BB.aBM0TO«B«B«BI>4«»rMrO«»«

i«=.ro»^«*»«i*»*i»i--ir-ir\M*«»or*jo< ioommmm*>-hoo» rs. — r» cm «*■»*-• ro •

i»-«i-)«»*««*ooro*t+"' " « » pi n « i

iN«t«MHCJOn + w -■ — — v ■_■ ro «»> I

i ■■ n mm m» «-« r-. ro ■* — — rs. ~. — \ *._•-#( i • m n • » m w - -. I — +»\ r- + mo i

> IB a» ■■ MM MB i—■ 0> 1 I I rv ■-• «— CM s f*S I

IMBmbummmbo-o — \ 1 S w NHM +1

IBBjMBMBjMBjMBjMBjMBtO-t- ) 1 T _ ** Op \ <

lHH«NHB*OMw —' 1 w q « .. (

IMBm*mb«*0*~ + \ I — >• ^ + «B> \ \ ■

# O MB M I

i cm *» *► l*s *

I «4 •» CM M O CM •

i «« m r- \ » • ro •» m o •»

■b. — o rv

i — • \ ■

— • — ■

i cm ■*

> m + ■

cm ro *

• »*■■}*■ *»H*»o*»*»aB**j«Ba>M«»«»orv

CM *

O *

I ■■ t4 *•> O —• s I 4-mmmmmbmbmbmmmbmb

IBBMh) v I + <*««MMM«N

I MB MB !-• (^J I S -'«»>«•■■■■■

i »-• m m i-i i i<— rsro«»»<iMBBBMBBB**

i mi m m — s — r^>->t-irvt-4CM>->oo4 i

I HN (M — V wHMH*t«-fNt«

i MM MM » Iv * N M M # — \ I I l\ ~ > CM + — I

CM .

CM

trots « osmjoiN" —

<r^\ s WMHM"»W»w.

irv l — 'NUNHMOHN'

■ *» •* — i

i »-i ro v i

— rv m i + cm ro i

* O * i

■ CM CM r» —

— I o —•

l~^ — MB ■

I MBJ MB O MB I

© O O O ■• — I

' # + M O ■•■ N I

■ — s >~> ft « CM *

s \ — + — rv ■

v I \ —.—,—. I

I I X \ -s — I

\ \ \ \ — - CM I

Q: Quit and Return to CP/M

This returns control directly to CP/M. If you want to save the collected data, this must be done prior to quitting the program.

R: Read In the File

The current disk will be searched for "filename.img", as specified in the initial command. If it is found, the entire data file will be read into memory. The maximum and minimum values associated with the data will be printed. If the file cannot be found, then an appropriate message will be printed and the user will be returned to the option-selection level.

S: Scan a New Page

The length of the scan line will be

asked first. Type in the decimal number of characters per line (1 to 255). You will be given a chance to position the paper before the scan is started. Hit the space bar to begin. The program will scan over the image in the print device until 255 lines have been scanned or a key has been hit. The maximum and minimum values read from the A/D converter are printed, and control is returned to the optionselection level.

T: Set the Tone Array

This is the heart of the processing system. For each column position, up to two characters will be typed to represent the A/D-determined intensity at this point. To accomplish this character substitution, two tone

arrays are used. A primary tone array is always used and consists of up to sixty-four characters chosen by the user. They are entered in the order of maximum darkness to minimum darkness. (Minimum darkness is usually a space.) A secondary tone array can also be given for overstriking characters to achieve greater density variation. This array, if given, is generally the same length as the primary array, although this is not required. The program will determine which character to use for any given value read from the A/D converter by the procedure:

SCALE = (MAX-MIN)/N INDEX = (VALUE-MIN)/SCALE if INDEX > N-l then INDEX =N-1

where:

MAX = the maximum integer value

in data.

MIN = the minimum integer value

in data.

N = the integer number of

characters in the tone array.

VALUE = the integer value read

from the A/D converter for this

position.

SCALE = the integer scale factor to

use.

INDEX = the integer index into the

tone array (0 to N-l).

The result of these computations (INDEX) specifies which of the N characters in the tone array will be used. A 0 refers to the first (or maximum density) character and (N-l) refers to the last available character (the minimum density). Note the value of (INDEX) is prevented from being greater than (N-l).

Integer arithmetic is used for all computations and, as such, the number of characters in the tone array affects the scale factor used. If the number of characters in the tone array is not an even divisor of the maximum-to-minimum variation, then the truncation that occurs in computing the scale factor has the effect of extending the minimum-density character until the number is an even divisor. This can cause large blank areas to appear in the final printout.

The tone arrays are entered using CP/M's buffered input routine. This means that all normal correction keys can be used on mistakes. Type a carriage return to end the line. To skip

242 February 1981 © BYTE Publications Inc

Please send your free software catalog.

(Check which software is of particular interest)

D C COMPILER. Optimized native code for VAX 11/780, PDP-11, LSI-11, Z80, 8085,8080. Full C language as defined in Kernighan and Ritchie, with comprehensive portable library. Cross compilers available. Runs under VMS, IAS, RSX-11D, RSX-11M, RSTS/E, RT-11, UNIX, Idris, CDOS, CP/M. From $600

□ IDRIS OPERATING SYSTEM. System calls and file system identical to UNIX V6, including pipelines. Utilities include shell, editor, assembler, loader, archiver, compare, copy, grep, etc., plus system utilities for file system maintenance. Runs on LSI-11, PDP-11. From $1000.

□ PASCAL COMPILER. Optimized native code for VAX 11/780, PDP-11, LSI-11, Z80,8085,8080. Full Pascal language as defined in Jensen and Wirth, with standard library. Includes C compiler and portable library, permitting intermixed C and Pascal. Cross compilers available. Runs under VMS, IAS, RSX-11D, RSX-11M, RSTS/E, RT-11, UNIX, Idris, CDOS, CP/M. From $750.

Name.

Company..

Street

City

.State.

-Zip.

Idris is a trademark of Whitesmiths Ltd. UNIX is a irademark of Bell Laboratories. CP/M is a trademark of Digital Research Co.

VMS. RSX-11, RT-11. RSTS/E. VAX. PDP-11, LSI-11 are trademarks of Digital Equipment Corporation.

Whitesmiths, Ltd.

Software for srownups.

(212)799-1200

RO.B. 1132 Ansonia Station, New York, N.Y. 10023

Prinary - "8EZi»;l*#B7AJ!«NBi032I7*+(!'-' "

Secondary-"««»#»«»«!!!!!

Table 2: The primary and secondary image-tone character arrays, with highintensity correspondence increasing from left to right.

the secondary tone array, just type a return. This doubles the output speed but won't allow overstrike on certain characters.

Setting the Tone

To help me decide which characters to choose for the substitution arrays, I wrote a simple program (though it's not included here) that took the character set as a dot matrix and looked at all overstruck combinations of two characters. The following algorithm

was used to determine the resulting intensity from each combination:

I(i,j,k,l)=RCI.[P(i,J,k) + {S(i,j,D -RCI*P(i,j,k)}]

INTENSITY(k,l)=sum I(i,j,k,l), i = l to n, j = l to m

where:

INTENSITY(k,l)= intensity value for character "k" printed over character "1". P(i,j,k)= primary character num

■}>■■»■■»■

- U M UU .

mWmmO«'-+ > •—» *»NJ

.WWWOWM-+ I to 1 *SI M

.ons-oro**** s t— i » m

.■b>mm«=»*omvi» I ro t W-sJ

U VVJNJ

WWWWWW

. +■ I ■«-■*- •••BMMMmMMMM*

. # I ■«-■•. '■■♦■mMMmMMMMMMmMMMMMMMM

SJ *■ ■+ • « \JM"\JM,«JNJ\J\JNJNJ'SJ>JSJNJNJNJNJ#NJ

■sj \J# "SJ + MMNJMSJNJNJMNJNJNJNJNJNJNJNJVJVJNJ

i SJ M

*

o

VJ

O

VJ

VJ

«

1

ro

VI

*

VJ

VJ

*

VI

VJ

VJ

VJ

VJ

VJ

VJ

VJ

VJ

VJ

VJ

VI

w

VI

VI

C-J

VI

C-J

♦

VI

*

*

*

VI

■*

VI

VI

VI

VI

VI

VI

VI

VI

VI

VI

VI

VI

M

VI

VI

-J

M

_,

M

M

h)

M

M

_

_,

M

M

_,

_

_,

_

_,

_,

fc,

-s,

M

M

_,

r->

M

h)

fc,

M

M

_,

_,

M

_

_,

_

„

„

00

CO

03

CD

X

x

X

00

co

03

CO

CO

MB

SB

*B

SB

sb

MB

MB

<BJ

M

+*

M

B4

CO

00

M

VI

VI

VI

VI

VI

SB

MB

SB

as

m

SB

SB

MB

<m

X

X

m

X

sb

X

X

MB

03

CO

MB

SB

SB

SB

SB

■B

■B

MB

MB

MB

MB

MB

MB

VI

VI

VI

VI

•"*

SJ

•SJ

•

s»

■

SB

■

■

■

mb

MB

MB

sb

MB

MB

sb

MB

mb

X

M

x

X

CO

*

m

SB

SB

■

SB"

■

■B

■B

■B

«B)

MB

MB

MB

MB

VI

VI

*

*

CO

O

00

x

co

X

X

CO

o

«,

t-j

co

m

ft)

BB

MB

BB

m

!fj

MP

MB

«

MP

MP

MP

PJ

VI

VI

*

*

VI

SB

MB

mb

■1

mb

MB

X

t-J

t-J

00

O

o

BB

BB

BB

BB

BB

MB

VI

VI

VI

VI

VI

MB

MB

MB

SB

mb

X

w

Cm

o

t-J

<-J

©

VI

sb

SB

SB

■B

MM

MB

■B

MB

MB

BB

MB

VI

VI

VI

•

MB

mb

■1

sb

CD

o

OJ

c~i

OJ

*

w

o

BB

VI

VI

*

VI

VI

a*

MM

SB

bb

mb

mb

MB

©

t-J

C-J

VI

+

*

*

t-J

C-J

X

X

IX

M

M

•BJ

■B

MB

MB

MB

MB

VI

VI

4

VI

VI

bb

MB

mm

MB

mm

MM

X

O

t-1

t-J

VI

VI

VI

*

*

■*

VI

(-J

©

*■*

M

•X

MM

MB

MB

MB

MB

VI

VI

VI

MB

MB

mb

SB

SB

m

o

o

t-J

VI

VI

VI

■1

*

-f

VI

4

OJ

M

«-«

+4

MB

MM

MB

MB

VI

*

■NJ

VI

SB

■1

•

■1

CO

o

t-J

VI

VI

VI

VI

*

*

VI

VI

VI

VI

VI

VI

SB

MB

at

at

M

C-J

VI

VI

VI

VI

VI

VI

OJ

CO

MB

MB

MB

MB

MB

VI

VI

N--JBBBBBMWOI imMBMBBMCOCDW' iNMMBlBJBJWaSHCOi iMMBBJBCDCDHNa'

. C-J 00 M M I

■ t-J t-J VI . t-J K> ■—

■ t-J M VI

■ «* t-J i—i p O t-J i—

■ t-J # t-J t-J VI «

' t-J t-J t-J VI '

» t-J O O '

o CO ft VI I

i vi sj + — —

SJUUOCOBCDBI

m U KJ * CO CO CO

■ O O I

iOU I

t-J O O t-J t-J

00-Ot-JVI»»+•* t-J CJ O — VI « -4- ■

w e u w u n vi +

OOt*Ot-Jt-Jt-JVI OOOMMOUi-4

t-Jt-Jt-Jt-Jt-JOhJi—I

I BB M CO MM

i t-J ro vi * sj

* sj sj

mobs s i

>UM SSI

* ■» sj

« SJ SJ

« B) SJ

* * SJ

iSJSJSJMBaaOBBBBMBaBI

1SJSJ«B4COOJMMBMMBI

VJVIVIMfOOCDMBMBMBI

1MMSJHNOCOHBBI

i vj —i vniownsssi

1MMMCONCOCOHSSI ISjMtOUMHHSSI 1 \J MM (J (J ImSIM«OCO»«HS)S)B) I M m « <BCD<MCO«HB)S) mMMCONBBSSSS 1MMMHSMCONBBB

-J — *COMB<«lMMMMBMB VI VI SJ0OSBBCOB4SBBSB VI VI * MBBBB*B«k»4IMBMB

IMMtCOSSSCSI

i O t-J i O t-J I

] SJ SJ M >-t >-t •

SB MB MB M CO O I MB MB M CO I

I M M # ■• a # ■ I M M « - - # I I m M • « M M i

(O SJ a + ■*■

SSSSSNHNOIO

M M CO

N H N

M M M

M COCO

H HO)

CO ■*> ■»»

oo «• oo

I t-J o i o oj

I M M M t-J VI

t-J t-J t-J 1— —1 -4- .

O O C-J ■— ■— VI

U U N M N * •

O O t-J VI K) VI

■ o o c»i sj sj * ■

<• O KJ » » — •

I t-J O t-J * + ■-

I N N UN m « '

1 U O SJ —. — \ I \

i W w M - - - -

VI VI * CO MB I

isssHCOi

' t-J t-J C-J VI —- -~ VI

M W N « - ■

SJ SJ SJ SJ (

1 « CO CO H N • 1 SJ 00 00 00 CO MB I • CD H CO IM BJ

* CO H «• CD H

* CD MB 0O CO M » 00 MB M CO M

* 00 SB M 00 00

SSMCOHMHHI

•> OSBSBBBSBSBBBSBOSJI

—.—..«■ sj o sj

O C-J — —• » " » M W "

roe + ■»■* » vi vi vi —

MO » NJ t M m M M M

MO + MM MH WM M .

ro ro o —i —i

.- vi m- .

OO OO M M 00

MB M CO

M oo oo

M CD M

CO CO

00 M

a> m

M 00 00 B) ■

ICDMCDOCDMCOCO.

> CO N N CO CO H »

> N CO CO CO B CO t

J M CO CD M CD CD +

■ 00 MB M M

I CDHOO INCOOO 1 B4 M 00 O

i B4 M o ro

CO CO C-J VI

w mu m

MCDO M

t-J O I

O O I

o o r

oj cj I

SJ + + »

SJ SJ SJ SJ

« CD BB MB 0O M ■

M CD S H CD S> I B CD • CO MB *

i S3 N H H H CD '

I H N 00 CO CO H 00 '

I O U M M h I

i CO M \J VJ M i

I CO U « * VI (

■*> ro sj .— — i

o « sj — —■ •

■O M- —- * -~

COOHSI

ibbMjmbsbmooom

ibssssshocoho

l**BBBBMBSJIB»MBC>jajM —

CO CO <• <

CO *• •

co co w <

CD M rxi # M M «- +

' MB MB O +

- » m M » - | SI U I

» VI M- * M- * S+t-Jl

M M m « M « I + t*i "

oi-tsjsjro* i • o i

o ro vj sj ro vj \mui

* m m h m » v ro a i

BMM MN • SfOOl

SJ SJ SJ SJ 4

MM M * 0D I M M SJ M B* I VI VI VI * «» ■

M MMMSI

1 CO 00 M <

I CO CO CO 1 CO CO O •

> CO 00 H H CO CO <

IBBMBMBSBMBCOMBMCO

* O M — i

# MH •> I

I — s O M '

i -~ — O M '

• m m o ro i

I N UNU i

I O M M ■»» I

■ ro t-j t-j o c-j ■

.« « U ONM I ' N CO « CO U H I

'SCOBNOSl

i t-J t-J + +

I CO CO O MB 00 00 mi

SJ

VI

_

M

«k

BB

■p

BB

SB

pp

MB

SB

M

_i

—

CO

NJ

MB

MB

M

CO

o

«F>

■_■

4>

IS1

«t

■p

■f

■p

CO

V.

■tr

MB

M

M

MB

MB

MB

MB

o

*

4

+

VI

M

VI

BB

SB

MB

MB

BB

M

t-J

MB

MB

M

M

M

C-J

M

M

M

MB

MB

o

VI

BB

MB

MB

o

MB

MB

MB

MB

t-J

•Mt

SB

MB

MB

o

+■

M

VI

MB

MB

SB

MB

MB

MB

MB

MB

MB

MB

MB

MB

M

•Mt

O

M

MB

o

*

M

VI

VI

o

MB

BB

MB

MB

MB

MB

MB

MB

M

M

M

•Mt

MB

MB

M

•Ml

MB

M

■o

•»

*

~J SJ

-•i

VJ

VI

o

o

*

**

+

VI

-.g

VI

C-J

MB

MB

MB

M

MB

M

M

■X

MB

■X

M

•4

■M

<M)

*-*

—t

M

M

M

pj

pj

CO

M

■X

MB

ea

VI

M

co

CO

X

M

00

w

M

X

t-j

+

SJ

It

■sl

—•

•-J

VI

*

*

VI

*

fc

VI

VI

VI

VI

M

VI

VI

VI

M

VI

VI

VI

VI

Vl

VI

*

VI

VI

Sj

M

*

VI

VI

VI

VI

*

*

ber "k", row "i", and column "]".

= 0, if this dot is not printed.

= 1, if this dot is printed. S(i,j,l)= secondary character number "1", row "i", and column "j".

= 0, if this dot is not printed.

= 1, if this dot is printed. RCI= ribbon condition index (range from 0.0 to 1.0). n = number of rows for character matrix.

m= number of columns for character matrix.

Using this method, I checked all combinations of two characters and made a list ranging from maximum to minimum darkness. (There were 4560 in all.) The resulting intensities ranged from 0 (a space over a space) to 27 (a # on an @). To account for the results of typing one dot on top of another, an RBI (ribbon-condition index) was used. It works like this: for a new ribbon (RBI = 1.0), two superimposed dots are not blacker than one dot. However, for an older ribbon (RBI < 1.0), the second dot will result in a darker intensity. A value of 0.75 for RBI seems about right for a normal ribbon. The characters I use for the Teletype 43 are shown in table 2. Note that the quotes (") at the ends are used here as delimiters and should not be typed in.

If your printer does not use a dotmatrix system, there are other ways to objectively judge character combinations. Write a simple BASIC program to print out a character combination and then position the phototransistor over this and read the result with the A/D converter. Or, of course, you could just guess. The characters listed in table 2 would be a reasonable place to start. Experimentation is the way to find the best character-substitution array for your own printer.

Recognition of Images

Pictures generated by this system are easier to recognize if they are "blurred" by moving the paper or your head rapidly, by squinting, or by viewing the object from a distance. This has the effect of reducing the geometric distortion caused by the sudden change in contrast from one character to the next. Such blurring can be automated. A simple procedure would be to select the intensity value at a given point by averaging the points around it. This average value is then used when

244 February 1981 © BYTE Publications Inc

this screen test?

WordStar™ does! And does it better than any other word processing system. Not only do you get all the sophisticated features youd expect from a high-priced WP system, with WordStar you will always have a true screen image of what your printout will look like before you print it!

With WordStar, you'll erase, insert, delete and move entire blocks of copy. Page breaks are

displayed and automatically revised on the screen. You can specify enhancements like underlining and boldfacing, and much more.

And WordStars so much easier to learn because of its unique and extensive self-help menus. Every typist in your office can be an instant screen star. Call (415) 457-8990 and ask for a copy of our WordStar demon

stration booklet. Remember, when you're the star, we're the star.

•Requires CP/M (TM of Digital Research), 48K, terminal with addressable cursor.

Circle 165 on inquiry card.

kioPio,

INTERNATIONAL CORPORATION

The Star Maker

MicroPro International Corporation 1299 4th Street, San Rafael. CA 94901 [415) 457-8990 TELEX 340388 Sold through authorized dealers and distributors only. OEM inquiries invited

BYTE February 1981 245

""l((t(»t»«I20BN8III- "-U«««7II7«('- ' '-'(((t"'-""-'<t«III7««"-!2It- '!♦•♦!--- ------ — -.-«/--

'""-I723222III0IS37""" '♦7I7«««t«7I0337<"' '"II ((♦♦♦•I2277II3INIBIHSBM02IIIX- "!♦('-'-"- " '" '

'-(♦•!-'"<3007<- " '♦I22«l'!U!'<7III7I3BIIIIM«XIIIIIJjmiH8BIIBBI07<-"-<*t- ' ' "'"" - ' ' """ '

'!»77<'-WI»»02«'"" -*I322«II 73«meM»IIIIIIIIIMMMIIII7«7II»IIIN««! '" ' " " '

-(7I7t(tI0«BIK»I*l 'KII'l«I0BHB07!t0IIMIIIBBBBIIIIBBBBIIIBBBIIIIHJ»«77IJIIJ3! ' ' '"""" -"

" '-(♦♦♦•70BIH07(""-"l!l'l»7II7730H80t'-3M*»IBBBBIIIIBBBBIIIIBBBBIIIIBBBJ»»7IBIJIIIIBI(MI'- ' '((-"" --'-'

""-♦7222I23MI037X-"' "-(730003233000I7347IIIBIIBIIIBIIIBIIIBBBIIBIIIBIJIBII7JIBIIIBJXBI2 '" ' --"- '

-(••tt>772Bi;Htl3t'""-(300327<730B02Billlllll||MIIBIIIIIIIBIIIBIIHBIIIBIIIBIIIIII7B37(-- 13»IIM3<-' '

M I'-' l«*IIIIIIIIII7il3I>20IINI<ll8l<l<IIH*3NIIIIIIH»IMIIIIIIIIIIII777777lll777MIIIIIMIItZN008«2<( '"! I II30I7IM7777I11*'-"' I

lillllllllllllllllllllllllllllllllllllBIIM««»0BBIIBBIIIIIIIIBBBIBBJI»003300»8l<7BIIBIIIIIBIIIIJIBB7l7ll777777l77777l77IJIIIIIIIIIIII

• IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIMI77IX23IIIIIIMHIII7III»<«7«*" -.IH7ltlltlMIM7I«BHIIIMIimillMMIMIIM« I

IIIIIIHIIIIIIIIIIIIIIMIIIIItlllllllimii020MimiM7l2< .8I77777IIII4M3 B BBBBBBB

BIIIBIIBIIIIIBIIIIIIIBIIBIIBIIIIIIIBIIBIIIBI0U7I »3(' (2MIIHHIII»BNBBHBIBIBIIIIIBI»tBII»tBII»IBHIIII

• BBIB IHHHHHHHHIBBHHHtHHMMBBBBI ♦ XIIIIIIIII77IMBI»IIIBIIIIBIIHBMMMiHlilllll

lllllll|llllll|BI|IIIBIIIIIIIIIIIBIIIIBBIIIIBM»llltBMI('-- <♦♦!-" "-llaBilBilUiltltBIBIBIHtHHIIBIfllllHMBMIM

»|»HIH»MHB»»IBB«BBIIBBBIBBIIBBIIBBIIBB«BBI7IHII7( (»•«»♦('-' ' IIIIIIIIIIMII I HMMMMMM

MMMMMIIMIIIIIMHIMIMHIMIIMIIHIIMIMIIHO - ".I22<- " !72I*e7llllllillllllllllllllllllllllllllllllllH

|||„||| Illlllll Illl Illlllllll!*! "*20««37*+l- Ml-" " '-'4|||IIIIIIIIIIIIIIIIIIIMIIIIIIIIIIIIIIIIH»

• •IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII7II7 -I- — 'I7IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIHIMI

IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIH70t(" ' 7HIIBIBBIBIBIBIBIBIBIBmBIBIBIIIIIIIIIIIIIII

IIIIUIIMMI77777777777IIIIUI IMIIMiMMIIIK ' 38I4I7I477777I7777774777I7IIIIHIIIMMMIHIII

IIII««7I«<'--" "l(" -<('-""--'-'<♦<" '18NIIie«30»l7llllll7IHHX»IHIIIIIIIIIIIIIIIIIIII

ttttl''l'-' '." ....... ..,...\.-. .,,.,. "l220003H7IO«l8eeiNH»0IHIIIIIIII777777777«77777l

I2I2I7«««"«*t«t*t«t< «♦♦♦♦♦♦♦♦♦»♦♦<♦<♦*♦♦«♦♦♦♦••••«♦♦♦♦< I-" "--'" - - - "I»t<7«a»aat«a<a777123338l7tlltlt7l7llil7it6il7ltt

00330033332I7«»a77aataaaaaaaaaaat<(«t«»*«»aaaaaaaataaaaat<-" """ - '" " 'I ♦*aaaa*aataaa7«777222308X7HIII77«M».*.*.#.7»»7»777l 888eilH«llie»277«»««t«t»*+»*«((((((«tt»««»«<t»*««t»«"<«<»*("' ' ' ' ' ' \ (..,..♦7I22277»7»722300KHIIIIII777I«»I«77777777I

»t»»HIXIIIlXII37aaattaaa«a(«(<(<(t*t«aa*aaaaatat(*taaaaaatt*a<- ...... '"••*7>I0«IH»I7>7>7I230H<7IBBItimiI«i7lllllllll

33338M77777»e0I7«*»(»t»t»tt*t((»»*«*t»«tt»»«»«*»t«»««***»««»!-' "" ' ' ' ' I (t>70eilII27««>7II30«I7ll7ll77MlUU7IIH7IH7

0OOOeillII77»K»2««««((**»*U(((U«t+»»«*«*«««*»»«««t(!((t+«('-' ' . . . > "-"-(78IH*3I7»«II30«»ll777l777l«m»l77l77777l

OO00aMNtNHNtXN*2***((* + < !<(<<( €++♦++♦♦++♦♦+•♦♦+♦♦< (!"-'l"ll-' '..'.' "-7I7*!"" (2»02777IIO»IMM7lt777#.HII»777l77lll7 »tMKIlIIHM7If.2atta(<<<<<<attata«ata*<(((«a**«*«a(<-"'"<7I7- ' - - ' "| 1303217*1'-' 'I♦7a7II0BIIIII7l777»Ii«I4i777l777777

88eeNIIIIII»«N32»«t»*«**<((t«*»**«4***»( ((♦♦..♦♦(♦((-"-'.7II7C-" ' ' '"-<70M0022I7««"-" U»II0NIIBBI7BII7<mXMI77l77l77l

""l7I30H00*0Iat*at*at*at*«a«at«aaaaa«(<(aaatt('-' — l«7I2IIt"-'"-'-(t«"2»»8»00033227«tl — -/IMIIII7M77tMIIIX777l777777

77773Mm030«02aat*«a*«tt*aat*««t*aaaaa< (♦♦♦(- -'I»7I3302« " l«7t"I0B8»»»l0033I77tl I'- -'3X177717711111111711777777

""'♦72332120027 •••••••7«7777«t('- IIO7I23002 -"-'♦2B8BfltllOI033II77« I'I'--'"""—I3NJI77II4IIIII7III7II77

77777«t«<12300327777 7777IIIIII<»I-"""""—' I (♦•7II330I07-'" -l2888MH0*003332I27tttt< ((I-'—""--l8I«iIIIXIIilll77B777

'r'l(aaIII222II7777aaaa<|"||(t77a|-'" ""—' |(«.7II233»I»0»-" I208I88MH000033332I 7aaata!""!'-*IIIIXIZIXI7II777777

'"-'—'llll(««««*(ll'-'" "--'""--M(«771122200t8l7*7»»IH«mOO»00033037»«»»t»771II7722II(I27('"»OIIIII777l77I777

ll"t«('(«UI«('-""" ' '.'...: "'-'I<<*77III22300800*00»0M0»00I000000027 ♦«7I21I2I3»0I232«t( I "I3IXXII7I77IIIII

-'"-((I :----<----'-'- -- "tm "—'((«»III223003300000000000000000I0I7««7 7I22I230BI00027«7«(t>IIIIIIIIIIXIXII

.......................... ----__-t3j,-_- |.......... |«4>7II23322000030000000330300t3I7I7»777>>II72II30mM»27I7>«I2I0IIIIIIIZXIXII

- - - "-K'|203aWa(l'l"—"lt««77I22233333333330333333303II777»77777III2I200»00NH022I7>I0273IIXIiitltilt<

"'74l73027«*(!' "<<<777I2332322322223222220027»«»7"77777II7II2IH00NBI32I7730"3NIXX7III7777I

' '«(13II3803a*»< 11'---'---1 <«7722222I222223222II2203I7»««*4«»7I7I77I77223MOO»H3322I28I! «7tllal7l7ailll

" ' !2270KHINOI7««Ut(!l""(»722232222322222222220321777»««4«7I7IIIII7220«l08IN000323«0<'**«8H«»777»XI4

....... ......... ---|!-'70228»8IIH3I777»7»»t(ni72303222322332322222233i7777»«+«7>»I7I77IlI230ro»fll«6b033e87«(*r'IIZ4»77J«III

- "'-II>'l«»03BBNIBB032II77>tt(«I0033223233232232222032277«»<7»»»><t7»77III333008IN«l«00«N3IIII7«(7MM77*liII

" — II0III2H»Mttl8»32III7aa200033333333323223230»03327 7a*aa*aa7aa77I33300IIB88«INNIaIIIII777BM77iiXIII

'" ' ""*I3B3aaI0HIXtXIB8t322I23«000003332222233333l0003332I7aaaa7aa7 ••77I3300BXNNINNIB033322002770BI77KIIX

Mill—'--"" '" "-IO0BNItl7t70l8XiliII88tl08B«ll003033333333330l003300033I7777I7>7*» III233BIXI«IIXI033323002>723NX77«XIII

'" "I«*3»eK«8l»l8«HI7«IIIIHH88ee»8»«»«000333330ll00300000332I77II77«t«»77»ni23IX7lll7»H0303300»lI«3330N777»HX

'"-'Ht2I30ll8ll888l*BII77«IIIIBN88BBBe«l0»00000»l033000000000322IIIII77II7III22308IBIIIlB0000008Ne2I2003«8l}7<III

'-MUM (I — !OII3I30«8868e8KHI7l7W»IIIHH»MK8ee»nOOOM00000000030300332HI7I7«77722233»N7IIIM800«OONIIOI2330330»X»7»IX«

-'taII7(ll<«II7l'<0tBXI20BIIM88tB8l7li8BIIXXIIIIIIBIHH8«8HIIBBmeBBH00300002IIII7aa77II200«I7IIHIIIH088I«l2I200322222NNB8Ml

" (•I308IIIIII0I770«0BIH33B8B8«IBBK«7K«(' — I l>30KXt7«t<IZBBBBXIIIINMI«BMB8««l0033I777III3l8BIIBIBMB«BBNitl3II333322I7II0«00332

'" —(7ItNIIII«llB23*030B80»NN8*00»N*7*2 (♦•II200»««IIKN88IIII03277« ! I'-'-'! (I2IIIIH868ll7»e2113332I77»»"«n77< !'

' lt73«B«HBBB0II»83I2ll0»BltH0tBI7B«'" ....... ---------- -- '"28IIIH8BIt7IN2IIII2I7>«( (I '"-'—-

'-' ln'(OI8l»l«032>tIBB3II2033BB«««8M8("""'"" ' ' " "" ' "'2II«K«IX7IIII7««t<('

""-|.I33027ie«8l0322I»(«3IIOI7I230l«IO«X»3'- '-«8K»HH«7X02I7»«*(( I"—"-"-' '

llll"<3IMII3IO«»00330I"«08H»3II2300H8I»2/- ' . . .... ...... '(0B8II«K3I77aaat<(I'---" -' """."

"-|2»H||H»0B8B«0»M«t'-t70M3II230MBII«- ■''.'' ' ' ' 't II8II«27«*«*« (((!"--' ' - ' ' '

-"l'<0»l«IU»IIOO»N3*"-<7232I77233$III l20NB27aaaaa< (|'"-"

'|""-'(«723330IB3(-'-'l«77«<7I20»3 -I0»I7aaa«taa(((I-'--' '

"(((♦♦((♦♦(♦7I3BB3('-"(t»777I23«- (72II7»«7»*»*++++< 11'-'-' .......... .

' '"" "at708«2a|'l(aa777I20887al'-' ' ' " ' " "" " '"♦•7777««««*«t*t( (111'—"""-"""" '

' "♦ll<7002a<l!(<a.7I2tll»""'"" " ' '" ' '"■"." ' " -|73I7I7a7a7a»aaaat*(((|l" .............. ,

' ' '-♦»IM»000I»((«»77I22»KBI-"""" ' ' "" ' ' "" " ' '"<a72I77aaaaaat ♦♦(<!'" ----_--<-------

......... - <--'-"<|,2M7«X»I«U*77II20S8l' '-'--'-'' "" " "--(71 II7«7.•»••♦*•»♦.*♦(♦♦( I \'-'—'-■...' -"

••«•!('(" "1"-(7«lI*B3«t+»»II20»»|- ' ' " ' "" " " '-+lII7»7»»»+«++*+++*++**+ (+ (11"'-' '--'!(•«♦••((

• (((JINIJ*'" "♦•♦♦•♦-'"(20IXI07««7I230»IC" ' ,,,,.,, ,, '^}ian*************{ (♦((((♦((( 11 (11 11 11'***7******** IIIIIIIIIIIt-""-l3«3II-"-l(I0BI(0I77I230l8*"" ' ' ------ - -|«3332I7»(t( (♦♦♦♦♦*♦(♦( (((((((11 (III lll'l !'♦♦((( (11 (()(

IBIB88HXIMI<7t-'(«2»l2l-"-'(«2B80I7I230H»IM0I«*l ----- '23003327«»l 1111 ((I !♦(( ((((((11 (I ((l( I'l I'11 (♦♦♦( H1111II

2222088BI<H02083l'«2201('(t«*'"«133220»8X»ll322200»l»HNKIIIIK8l8»032II77230027«t«*t««*»«*«<(((((lt(l(((((«(<((((l(ll((( ♦♦•♦♦(

"Illl'III I(('-«I007"(I3l8«3II2320«lttBIMItHtIXIIIIIIIIIMt7«t77ll70«t«t>IIIII77>7<»»«>t«(lt(lt(♦♦♦•♦♦♦<<((((I(1*777122222177

-"l«I080*"-'«I3Hlie«30«l7ll7»m»7l77777llll7l77IIIH7«IH«7««772III7<7 ♦<»(((((*♦<»«♦<((((( I <( I ( +7112223 222111

" -(7738N37I—' (*720e8»0HIII4*l«888IH7777»«7IIIH37*!- -I (••♦♦( !♦((♦((( ((I K (((((( (♦(({ IIIII (I ♦•7212333322211

'••71»M03I«("lt»I3000»»BBBBIBHIIIJ4XXBI»l-'-' ' ' '111 l""l"l"l'l"l'" II 1*72333300033333

"" "'♦I770B07tl(((ll'l(I30«8»IIIIBIIIBIIIIB«' - , - >--((,(,|- I <723«008888«I«|8

"-"-"-"--"-(7I7('|»(|-,j7I21.t((«20»IHimilll»t- ------ - ---.308»U027«('-'"(((I"-- (((♦(♦••20B88BNIIIIIXII

—'-'-"""""II23I3BHMIt«< II'l<7I2tKIIIIIIIIIIN!- " -"""" '"<It88N8NIIIIIINNIINN»37«l " (72I««««II28IIIIM777«7I77

7777»«tl — '-'(*»33I30IO«l«e83tI2«'!2KIX7lllllllll8« ' " l38N8»888«l»l0300»KHNNHN88IIXIXXIIIIIie<iOOI4»»«»777777777

selecting an appropriate character to print. Different amounts of blurring can be simulated by using more or fewer points in the averaging process. Obviously, the current program would have to be modified to accomplish this.

Area for Further Investigation

Due to the digital form of the data, an area that would be interesting to

look into is anamorphic art. This term refers to pictures that are greatly distorted (usually by some geometric procedure) and the original contents are difficult to recognize without transforming the image back by an appropriate means (like curved mirrors). A description and analysis of anamorphic art is contained in Martin Gardner's "Mathematical Games" noted in the references.

Because the images are in digital form, transformation becomes a mathematical problem and not an artistic one. I am sure that many enthusiastic hobbyists can produce fascinating pictures along these lines.

Running Under Another Operating System

This program can be modified to run under most operating systems, in

246 February 1981 © BYTE Publications Inc

H

CQITIPLITRQNICS

N C.

• • • EVERYTHING FOR YOUR TRS-80 • • •

TRS-«o In a trademark of the Radio Shack Division of Tandy Cor (Miration

1980 INCOME TAX PAC

Completely Revised • Latest Tax Tables • Fully Tested * Complete Manual and Documentation * + The New Version Of The Income Tax Pacs Are Full Of Error Catching Codes + *

* * Making It Impossible To Make An Error • • — Follow The Simple Step By Step Procedure That Makes Tax Preparation Simple —

L.

• INCOME TAX PAC A

FOR LEVEL II 16K

• DOES FORM 1040 and 1040A

• SCHEDULE A ITEMIZED DEDUCTIONS

• SCHEDULE B INTEREST and DIVIDENDS

• OUTPUT TO VIDEO DISPLAY

• SCHEDULE C TAX COMPUTATION

_L

• INCOME TAX PAC B

FOR LEVEL II with or without Printer. Cassette or Disk Has all features of Income Tax A PLUS,

• WORKS WITH LINE PRINTER

. FORMATS FORM 1040 and 1040A FOR TRACTOR FEED FORMS

• SCHEDULE C INCOME FROM A PERSONALLY OWNED BUSINESS . FORM 2106 EMPLOYEE BUSINESS EXPENSE

FORM 1040 (LONG FORM)

FORM 1040A (SHORT FORM)

FORM 2106 EMPLOYEE BUSINESS EXPENSE

FORM 2440 DISABILITY INCOME EXCLUSION

FORM 2441 CREDIT FOR CHILD AND DEPENDENT CARE EXPENSES

FORMS 3903 MOVING EXPENSE ADJUSTMENT

FORM 4797 SUPPLEMENTAL SCHEDULE OF GAINS AND LOSSES

* * PROFESSIONAL * * INCOME TAX PAC C

• SCHEDULE A ITEMIZED DEDUCTIONS

• SCHEDULE B INTEREST AND DIVIDENDS

• SCHEDULE C PROFIT (OR LOSS) FROM BUSINESS OR PROFESSION

• SCHEDULE D CAPITAL GAINS AND LOSSES

• SCHEDULE E SUPPLEMENTAL INCOME SCHEDULE

• SCHEDULE G INCOME AVERAGING

• SCHEDULES R & RP-CREDIT FOR THE ELDERLY

FOR MODEL I (32K) or MODEL II (64K)

WITH 1 OR MORE

DISK DRIVES

ALL SPECIFICATIONS SUBJECT TO CHANGE

• SCHEDULE SE-COMPUTATION OF SOCIAL SECURITY SELF-EMPLOYMENT TAX

• SCHEDULE TC TAX COMPUTATION

• OUTPUT TO VIDEO OR LINE PRINTER

• FORMATS FOR TRACTOR FEED OR INDIVIDUAL FORM FEED PRINTERS

• AUTOMATIC MEMORY STORAGE FOR INCOME TAX PREPARERS

• INSTANT LINE CHANGE

• BUILT IN ERROR CHECKING

•CQMPJTRQNICS

50 N. PASCACK ROAD SPRING VALLEY, NEW YORK 10977

PLEASE SEND ME:

□ INCOME TAX PAC A (S19.95)

□ INCOME TAX PAC B (S49.95)

□ PROFESSIONAL INCOME TAX PAC C ($99.95)

□ MODEL II PROFESSIONAL INCOME TAX PAC C ($199 95)

NEW TOLL-FREE

ORDER LINE

(OUTSIDE OF NY. STATE)

(800) 431-2818

• A COMPLETE LINE OF NELCO TAX FORMS

ARE AVAILABLE

• INDIVIDUAL FEDERAL and STATE FORMS

• 2 OR MORE PART FORMS

• TRACTOR FEED FORMS ELASTIC OVERLAYS

I • PLA!

+ All orders processed within 24-Hours * 30-Day money back guarantee on all Software • Add $2.00 for shipping in UPS Areas • Add $3.00 for COD. or NON-UPS Areas • Add $4.00 outside U.S.A., Canada & Mexico

CREDIT CARD NUMBER

SIGNATURE

NAME

.EXP DATE,

STREET.

CITY.

.STATE.

.ZIP.

Circle 166 on Inquiry card.

HOUR 24 ORDER LINE

(914) 425-1535

BYTE February 1981

247

eluding cassette-tape systems, if the necessary system routines are provided. The calling sequence for all CP/M functions is to specify the desired function by using the C register, loading any arguments using the DE register pair, and calling location 0005 (hexadecimal). Function results are returned in register A. The functions used by IMAGE are:

• Function 1: Read a character from the keyboard. This routine will return a character (with bit 7 cleared) in the A register. If a character is not ready, it waits until it is.

• Function 5: Print a character on the list device. The contents of the E register are sent to the printer.

• Function 9: Print a message. The ASCII (American Standard Code for Information Interchange) character string pointed to by DE will be sent to the console device. A dollar sign ($) terminates the message.

• Function 10: Buffered input. The register pair DE points to a character buffer that will contain a line typed by the user. The first byte must contain the maximum number of characters to be read; the second byte will

be set to the actual number read (less the carriage return). The following space will be used to store the input characters (bit 7 cleared).

• Function 11: Interrogate console status. This checks the status of the keyboard. If a character is ready to input (by function 1), the A register will be set to hexadecimal FF. Otherwise the A register is cleared.

• Function 15: Open a file. For this call, DE points to a FCB (file control block) describing the file that will be opened. The program uses the default FCB built by the initial command processor within CP/M. The file is opened for either reading or writing unless the A register contains hexadecimal FF, indicating that the file was not present.

• Function 16: Close a file. Pointing DE at the FCB for the desired file will cause it to be closed. All I/O (input/output) must be completed. The directory will be updated.

• Function 20: Read the next record. The next 128-byte record will be read from the file (DE points to the proper FCB). The data will be read into a buffer whose address is set with function 26. On return, A will contain a 0

Attention TRS-80 Mod II owners: P&T CP/M® 2 has more to offer!

More Disk Storage 596K bytes with double densityon standard singlesided disk drives. If that's not enough, versions are available for double sided expansion drives (1,2M bytes per disk) and the Cameo Hard disk system (10M bytes).

More CRT Functions P&T CP/M 2 has the most advanced screen driver available for the Mod II including: erase to end of line/screen, insert/delete line, cursor addressing, non-scrolling area on screen, and much more. More Serial I/O Capabilities The serial drivers in P&T CP/M 2 support ETX/ACK, XON/XOFF, and request to send handshaking. Direct control of the serial ports is also available for special applications.

More Documentation We provide the standard CP/M manuals and our own 150 page manual written specifically for P&T CP/M 2.

More Utilities We have added 14 of our own utility programs for the Mod II to the standard CP/M utilities. More Useful System Functions P&T CP/M 2 has all sorts of useful features you won't find elsewhere: type-ahead buffer for keyboard input, system time ofdayclock, automatic program execution, and lots more.

Prices Standard P&T CP/M 2 $ 185

P&T CP/M 2 for Shugart 850

2 sided drives $220

P&T CP/M 2 forCameo Hard

Disk system $250

Wealso carrytheseothersoflware packages:

Magic Wand text processor $350

VEDIT text editor $110

LYNC data communication program $95

MCALL intelligent terminal program $65

MAC macro assembler $90

Pascal/M $175

Microsoft Basic-80 Interpreter $325

Microsoft Basic-80 Compiler $350

CBASIC2 (improved performance) $105 Osborn accounting software (requires CBASIC 2; manuals extra) each package $95: all four $295 Also available are single and double sided expansion disk drives and the Cameo Hard Disk System. Call or write for details.

Prepaid. COD. Mastercharge or Visa orders accepted Shipping entra California residents add 6% sales tax.

>*-—^ PICKLES & TROUT

1 ROU 1 P.O. BOX 1206. GOLETA. CA 93017. (805) 967-9563

CP/M is a trademark of Digital Research Inc. TRS-80 is a trademark of Tandy Corp.

(if the transfer went properly) or a 1 (if the end of the file was reached).

• Function 21: Write the next record. The FCB pointed to by register pair DE indicates from which file the 128 bytes are taken. The address of the data must be set by function 26. On return, the A register should contain 0; anything else is interpreted by IMAGE as an out-of-space error.

• Function 26: Set the DMA (direct memory access) address. The next disk read or write will reference data at the address specified by register pair DE. If this is never called, hexadecimal 0080 will be assumed by default.

So there's my system. It's simple, inexpensive, and leaves enough room for your creative modifications such as manipulating blurrihess, shadows, outlines, overstrikes, etc. The possibilities are myriad—how about using colored ribbons on your printer to obtain different overstrike hues? Whatever modifications you design, enjoyment is guaranteed. ■

References

LBowden, J C and A K Scharschmidt. "Producing Pictures on Your Computer With a Diablo Printer." Dr Dobb's Journal of Computer Calisthenics & Orthodontia, Volume 4, Number 39, Issue 9, October 1979, pages 26 thru 29.

2.Gonzales, R C and P A Wintz. Digital Image Processing. Reading MA: Addison-Wesley, 1977. 3Gardner, M. "Mathematical Games: The Curious Magic ol Anamorphic Art." Scientific American, Volume 232, Number 1, January 1975, pages 110 thru 116.

4.Harmon L D. "The Recognition of Faces." Scientific American, Volume 220, Number 5, November 1973, pages 70 thru 87.

5.Hale JAG. "Dot Modulation for the Production of Pseudo Grey Pictures." Proceedings of the SID, Volume 17, Number 2, Second Quarter 1976, pages 63 thru 74.

6.McDonough T. "Computer Graphics With the Diablo." Creative Computing, Volume 5, Number 6, June 1979, pages 32 thru 35.

For those readers who do not care to type in a program as long as the one in listing 1, the author is willing to provide source code on a floppy disk for $10. The disks will be IBM soft-sectored format, written in single density, and will be compatible with CP/M versions 1.4 and 2.0. Contact:

Clark A Calkins

2564 Walnut Blvd §106

Walnut Creek CA 94598

Please allow 1 to 2 weeks for UPS delivery.

248 February 1981 © BYTE Publications Inc

Circle 167 on Inquiry card.

Start learning and computing for only $129.95 with a Netronics 8085-based computer kit. Then expand it in low-cost steps to a business/development system with 64k or more RAM, 8" floppy disk drives, hard disks and multi- terminal I/O.

THE NEW EXPLORER/85 SYSTEM

Special! Full 8" /loppy, 64k system for less than the price of a mini/ Only $1490.95!

Imagine — for only $129.95 you can own the starting level of Explorer/85, a computer that's expandable into full business/development capabilities — a computer that can be your beginner system, an OEM controller, or an IBM-formatted 8" disk small business system. From the first day you own Explorer/85, you begin computing on a significant level, and applying principles discussed in leading computer magazines. Explorer/85 features the advanced Intel 8085 cpu, which is 100% compatible with the older 8080A. It offers onboard 8-100 bus expansion, Microsoft BASIC in ROM, plus instant conversion to mass storage disk memory with standard IBM-formatted 8" disks. All for only $129.95, plus the cost of power supply, keyboard/ terminal and RF modulator if you don't have them (see our remarkable prices below for these and other, accessories). With a Hex Keypad/display front panel. Level "A" can be programmed with no need for a terminal, ideal for a controller, OEM, or a real low-cost start.

Level "A" is a complete operating system,perfect for ^beginners, hobbyists, industrial controller use. $129.95

LEVEL "A" SPECIFICATIONS

Explorer/85's Level "A" system features the advanced Intel 8085 cpu, an 6355 ROM with 2k deluxe monitor/ operating system, and an advanced 8155 RAM I/O ... all on a single motherboard with room for RAM/ROM/ PROM/EPROM and S-100 expansion, plus generous prototyping space,

PC Board: Glass epoxy. plated through holes with solder mask. • I/O: Provisions for 25-pin (DB25) connector for terminal serial I/O. which can also support a paper tape reader... cassette tape recorder input and output... cassette tape control output... LED output indicator on SOD (serial output) line ... printer interface (less drivers).., total of four 6-bit plus one 6-bit I/O ports. • Crystal Frequency: 6.144 MHz. • Control Switches: Reset and user (RST 7.5) interrupt... additional provisions for RST 5.5, 6.5 and TRAP interrupts onboard. • Counter/Timer Programmable. 14-bit binary. < System RAM: 256 bytes located at F000, ideal for smaller systems and for use as an isolated stack area in expanded systems ... RAM expandable to 64K via S-100 bus or 4k on motherboard,

System Monitor (Terminal Version): 2k bytes of deluxe system monitor ROM located at F000. leaving (WM free for user RAM/ROM. Features include tape load with labeling ,., examine/change contents of memory... insert data... warm start... examine and change all registers... single step with register display at each break point, a debugging/training feature. - ■ go to execution address ... move blocks of memory from one location to another... fill blocks of memory with a constant... display blocks of memory ... automatic baud rate selection to 9600 baud ... variable display line length control (1-255 characters/line) ... channelized I/O monitor routine with 6-bit parallel output for high-speed printer... serial console in and console out channel so that monitor can communicate with I/O ports.

System Monitor (Hex Keypad/Display Version): Tape load with labeling ... tape dump with labeling ... examine/change conlentsof memory ... insert data ... warm start... examine and change all registers ...

(Also available wired & tested, $1799.95)

Full 8" disk system for less than the price of a mini (shown with Netronics Explorer/85 computer and new terminal). System features floppy drive from Control Data Corp., world's largest maker of memory storage systems (not a hobby brand.')

single step with register display at each break point... go to execution address. Level "A" in this version makes a perfect controller for industrial applications, and is programmed using the Netronics Hex Keypad/ Display, II is low cost, perfect for beginners. HEX KEYPAD/DISPLAY SPECIFICATIONS Calculator type keypad with 24 system-defined and 18 user-defined keys. Six digit calculator-type display, that displays full address plus data as well as register and status information. LEVEL "B" SPECIFICATIONS Level "B" provides the S-100 signals plus buffers/ drivers to support up to six S-100 bus boards, and includes: address decoding for onboard 4k RAM expansion selectable in 4k blocks ... address decoding for onboard 6k EPROM expansion selectable in 6k blocks .,. address and data bus drivers for onboard expansion . . . wait state generator(jumper selectable), to allow the use of slower memories ... two separate 5 volt regulators.

LEVEL "C" SPECIFICATIONS Level "C" expands Explorer/65's motherboard with a card cage, allowing you to plug up to six S-100 cards directly into the motherboard. Both cage and card are neatly contained inside Explorers deluxe steel cabinet. Level "C" includes a sheet metal superstructure, a 5-card. gold plated S-100 extension PC board that plugs into the motherboard. Just add required number of S-100 connectors.

LEVEL "D" SPECIFICATIONS

Level "D" provides 4k of RAM power supply regulation, filtering decoupling components and sockets to expand your Explorer/85 memory to 4k (plus the origi

nal 256 bytes located in the 8155A). The static RAM can be located anywhere from jflfinfl to EFFF in 4k blocks.

LEVEL "E" SPECIFICATIONS Level "E" adds sockets for 8k of EPROM to use the popular Intel 2716 or the TI2516. It includes all sockets, power supply regulator, heat sink, filtering and decoupling components. Sockets may also be used for 2k x 8 RAM IC's (allowing for up to 12k of onboard RAM). DISK DRIVE SPECIFICATIONS

• 8" CONTROL DATA CORP. • Data capacity: 401,016 bytes professional drive, (SD), 802,032 bytes (DD),

• LSI controller. unformatted.

• Write protect. • Access time: 25ms (one

• Singleordoubledensity. track). DISK CONTROLLER/ I/O BOARD SPECIFICATIONS

• Cont.-ols up to four fl" drives. • 2716 PROM socket included

• 1771A LSI (SD) floppy disk for use in custom controller. applications.

• Onboard data separator • Onboard crystal controlled. (IBM compatible). • Onboard I/O baud rate

• 2 Serial I/O ports generators to 9600 baud.

• Autoboot to disk system • Double-sided PC board when system reset. (glass epoxy,)

DISK DRIVE CABINET/POWER SUPPLY

• Deluxe steel cabinet with individual power supply for maximum reliability and stability.

ORDER A COORDINATED EXPLORER/85 APPLICATIONS PAK!

Beginner's Pak (Save $26.00!) — Buy Level "A" (Terminal Version) with Monitor Source Listing and AP-1 5-amp Power Supply: (regular price $199.95), now at SPECIAL PRICE: S169.B3 plus post. & insur. Experimenter's Pak II (Save $53.40!) — Buy Level "A" (Hex Keypad/Display Version) with Hex Keypad/Display. Intel 60B5 User Manual, Level "A" Hex Monitor Source Listing, and AP-15-amp Power Supply: (regular price $279.35). all at SPECIAL PRICE: $219.93 plus post. & insur. Special Microsoft BASIC Pak (Save $103,001)— Includes Level "A" (Terminal Version). Level "B". Level "D" (4k RAM). Level "E". 8k Microsoft in ROM, Intel 6085 User Manual, Level "A" Monitor Source Listing, and AP-15-amp Power Supply: (regular price $439.70), now yours at SPECIAL PRICE: $329.9$ plus post. & insur.

ADD A TERMINAL WITH CABINET, GET A FREE RF MODULATOR: Save over $114 at this SPECIAL PRICE: $499.9$ plus post. & insur. Special 6" Disk Edition Explorer/83 (Saveover$104l) — Includes disk-version Level "A", Level "B", two S-100 connectors and brackets, disk controller, 64k RAM, AP-1 5-amp power supply, Explorer/85 deluxe steel cabinet, cabinet fan, 8' SD/DD disk drive from famous CONTROL DATA CORP. (not a hobby brand!), drive cabinet with power supply, and drive cable set-up for two drives. This package includes everything but terminal and printers (see coupon for them). Regular price $1630.30. all yours in kit at SPECIAL PRICE: $1499.9$ plus post. & insur. Wired and tested, only $1799.95.

Special! Complete Business Software Pak (Save $625.00!) — Includes CP/M 2.0. Microsoft BASIC. General Ledger. Accounts Receivable. Accounts Payable. Payroll Package: (regular price S1325). yours now at SPECIAL PRICE: $699.95.

Please send the items checked below: D Expl0rer/85 level "A" kH(Terminal Version). . . $129.95 plus

$3 post. & insur. D Explorer/83 level "A" Idt (Hex Keypad/Display Version). . .

$129.9$ plus S3 post. & insur. □ Bk MlCrOSC-fl BASIC on cassette tape. $64.95 postpaid. O 8k Microsoft BASIC In ROMIdt [requires Uvels "B", "D" and

"E")... $99.95 plus 12 post. & insur. DLevel"8"(S-100)Idt. .. $49.95 plus $2 post. & insur. D Level "C" (S-100 6-card expander) ki t $39.95 plus $2 past.

& insur. D level "D" (4k RAM) Idt... $69.95 plus S2 post. & insur. D level "E" (EPROM/ROM) Idt... $5.95 plus 50« p&h. D Deluxe Steel Cabinet for Explorer/85... $49.95 plus $3 post.

& insur.

□ Fan For Cabinet . . . $I5.00plus SI 50 post. & insur.

D ASCII Keyboard/Computer Terminal kit: features a full 12s

character sel. u&l case: full cursor control: 75 ohm video output: convertible to baudot output: selectable baud rale. RS232-C or 20 ma. I/O. 32 or 54 character by 16 line formats, and can be used with either a CRT monitor ora TV set (if you have an RF modulator) . . . $149.95 plus $3.00 post. & insur. D Deluxe Steel Cabinet for ASCII keyboard/terminal . .. $19.95 plus S2.50 post. & insur.

D New! Terminal/Monitor: (See photo) Same features as above, except 12" monitor with keyboard and terminal is in deluxe single cabinet: kit... $399.95 plus S7 post. & insur.

D Hazelllne terminals: Our prices loo low to quote— CALLUS

D Iear-Slgler terminals/printers: Our prices loo low to quote: CAULS

D Hex Keypad/Display Idt... $69.95 plus S2 post. & insur.

D AP-1 Power Supply Kll ±8V ® 5 amps) in deluxe steel cabinet

. . . $39.95 plus S2 post. & insur. D Gold Plated S-100 Bus Connectors... $4.85 each, postpaid.

□ RF Modulator HI (allows you to use your TV set as a monitor)

... $8 95 postpaid.

D 16k RAM Idt (S-100 hoard expands to64k). . . $l99.95plusS2

post. & insur. O 32k RAM kit. . $299.95 plus $2 post. & insur. a 48k RAM kit.. . $399.95 plus $2 post. & insur. D 64k RAM kit $499.95 plus $2 post. & insur. D 16k RAM Expansion kit (to expand any of the above in 16k

blocks up to 64k) . . . $99.95 plus $2 post. & insur. each.

D Intel 8065 cpu Users' Man ml... $7.50 postpaid.

D 12" Video Monitor (10MHz bandwidth) .. . $139.95 plus $5 post. & insur.

□ Beginner's Pak (see above) $189.95 plus S4 post. & insur.

D Experimenter's Pak (see above) . . . $219.95 plus $6 post. & insur.

D Special Microsoft BASIC Pak Without Terminal (seeahovo|..

$329.95 plus S7 post. & insur.

D Same as above, plus ASCII Keyboard Terminal With Cabinet, Gel Free RF Modulator (see above). . . $499.95 plus $10 post. & insur.

O Special 8" Disk Edition Explorer/85 (sen above) . $1499.95

plus $26 post. & insur.

O Wired t, Tested $1799.95 plus $26 post. & insur. D Extra 8" CDC Floppy Drives. .. $499.95 plus $12 posl. & insur. D Cabinet £ Power Supply For Drive .. $69.95 plus $3 post. &

insur.

D Drive Cable Sei-up For Two Drives... $25 plus $1.50 post. &

. $199.95 plus $2 post.

D Disk Controller Board With I/O Pons.

& insur.

D Special: Complete Business Software Pak (see above) ...

$689.96 postpaid.

SOLD SEPARATELY: DCP/MI.4. .. $100postpaid. 'J CP/M 2.0... $l50poslp,iid. D Microsoft BASIC... $325 postpaid. D Intel 8085 cpu User Manual. . $7.50 postpaid. D level "A" Monitor Source listing... $2$ postpaid. ^m Continental U.SA Credit Card Buyers Outside Connecticut ^

I CALL TOLL FREE: 800-243-7428 m

^H To Order From Connecticut Or ForTechnical I^V ^ Assistance, call (203) 354-9375 ^

Total Enclosed (Conn res. add sales tax) S

Paid By:

D Personal Check D Cashier's Check/Money Order

□ VISA D Master Charge (Bank No )

Acct. No. Exp. Date

Signature

Print

Name

Address

Cily

Slate

. Zip_

■^ NETRONICS Research & Developmenl Ltd. ISA 333 Litchfield Road, New Mllford, CT 06776

Southern California

r o

Q.

a O

ia>

(D

i.

CO

O

CO

'c o

ra O

c

3 o

03

O

r

CD

>

■a <

Southern California—a mecca for engineers—is rallying in anticipation of a booming business economy because of increased military spending expected under the new Reagan administration. The result is that the demand for electrical/electronic, computer science, data communications or aerospace/aeronautical engineers in the Golden Gate State has never been better.

As one engineer working in Southern California recently remarked, "If an engineer doesn't like the job, he or she can literally walk across the street to another one."

The hub of Southern California's aerospace activity is located in Los Angeles County, Orange County, and San Diego County, areas which in 1980 utilized the talents of 55,859

engineers. This year, according to economists, an additional 15,040 will be required by the high-technology companies that need them.

With 40% of the total aerospace population employment in the United States located in Southern California, New England, another high technology area, runs a distant second, providing 14% of the nation's aerospace engineering employment. Southern California will continue to outshine the rest of the nation in this industry during the 1980s because of two reasons:

1. The projected spurt in defense spending by the Reagan administration.

2. The construction of commercial, fuel-efficient jet aircraft that will be sold here and abroad.

A spokesman for a major aircraft

manufacturer says, "There's talk of a new military bomber, either the B-1 or another one. There is even the possibility that the MX missle program may be sited for our state, and that the cruise missile program will be accelerated. The Polaris, a submarine-launched missile, may also be built here."

Another engineer at the plant of a major aircraft manufacturer confided, "Because Reagan is homegrown, we hope he'll let us build the B-1 bomber here." He added that in addition to the need for aerospace engineers, there are also great opportunities for those interested in alternative energy sources.

The reason is that tax credits of 25% to 50% are awarded to anyone who installs solar heating. Approximately 100,000 solar-heated

250 BYTE February 1981

homes and businesses exist in the Golden Gate State. Obviously Southern California is a hot market for this field, which is growing in importance.

The computer business is also booming, and companies are scouring the country seeking engineers with the qualifications necessary to develop the high technology products we need for tomorrow.

In addition to the progressive scientific climate, the weather in Southern California is "the closest thing to perfect," according to the United States Weather Bureau. The average temperature isasunny71 degrees, with only 14 inches of rain a year, falling mostly between November and March. ("It never rains in Southern California," so the song goes.) The proximity of the ocean, the

desert, and the mountains makes it possible to ski, bask in the desert sun, and swim in the Pacific ocean, all in the same day.

Southern California's standard of living is one of the highest in the nation: the median family income in Orange County in 1980, for example, was $29,000. Los Angeles families averaged $26,000, Santa Barbara, $27,000, and San Diego households took home $24,000. But the Catch-22 on housing is that the median price was a whopping $100,000, and this substantial rate is exacerbated (if not caused) by a housing shortage and high interest rates. Businesses employing engineers are, in some instances, trying to circumvent this problem by paying part of the interest rate on the mortgages of employees that relocate. For example, if the mortgage rate is 14%, the company may pay 4% of the cost.

To help ease the housing problem, business-oriented Lieutenant Governor Michael Curb has assembled a task force of real estate, government, and labor officials. He blames rent control for the shortage because he says it discourages construction of new housing.

"If we could increase the supply of houses, demand would diminish, and so would prices," an aide says. He adds, "Average personal income in the state is the highest in the country; it's $9,900 compared with a national average of $8,700. Housing is the only major stumbling block to an otherwise excellent quality of life."

He concludes, "Today business is no longer a dirty word. It's a four letter word meaning jobs."

This statement is borne out by recent figures that show that California will continue to grow at a rate of 30% to 50% through the mid-'80s. Economists in the state predict that there will be 300,000 new jobs needed for manufacturing in the next few years, a sure sign of the state's vibrant economy.

Another advantage of living and working in Southern California is that it offers engineers the opportunity to continue their education. The University of California at San Diego, for example, boasts three Nobel Prize winners on its staff and 36 members of the National Academy of Sciences.

California Institute of Technology in Pasadena is another first-rate school for engineers.

In addition, many of the high

California's Lt. Governor, Mike Curb, is working with a task force of real estate, government, and labor officials to help ease the housing problem.

technology companies in Southern California offer their employees in-house courses. In some cases engineers are updated in their specialties through the use of closed-circuit television beamed from schools in other parts of the state.

Most companies encourage their engineer employees to upgrade their skills, and many pay full or partial tuition.

To sum up, the demand for engineers in beautiful Southern California in this decade is expected to remain strong. The salaries are high, the work is both exciting and important, and industry is hiring at an accelerated rate. In addition, the Golden Gate State offers a lifestyle with every kind of cultural and recreational activity available anywhere in the world.

As one Southern California economist put it, "Where are all those engineers? We need them."

If you area recent graduate or a veteran engineer seeking a virtually unlimited future, the Golden Gate State offers an opportunity that you may never have again. If you are serious about your career, are an electrical/electronic, computer science, data communications, or an aerospace/aeronautical engineer, don't miss the following Southern California Career Opportunities Section featuring blue-chip companies that are interested in you and your talents now and in the future.

—John Brand

>

Q.

<

3. o

0)

o

c

3" CD

3

o

B ^» O

-^ 3 0>'

O

^

CD

o

■o ■o o

3

BYTE February 1981

251

SOUTHERN CALIFORNIA CAREER OPPORTUNITIES

Who will be first with the avionics of the 21st century?

It could be you and Hughes Radar Systems.

We pioneered pulse Doppler radar and built the first operational airborne programmable signal processor. Today, three out of the four front-line U.S. tactical aircraft have Hughes radars. We're leaders in synthetic aperture radar, in-weather reconnaissance and strike radar, high order language, antenna arrays and holographic displays. We're even building the rendezvous radar for the Space Shuttle.

And with computer-aided design, manufacturing, and testing of intelligent radar devices, the future is at Hughes.

In fact, Hughes is one of the nation's largest employers of electronic engineers and a major employer in virtually every other scientific, computer and technical discipline — with 1,500 projects and a backlog of over $5 billion. Yet we're decentralized to give you the kinds of environments that stimulate innovation and promote recognition of your work.

Who will be first with the avionics of the future? It could be you and Hughes.

At Hughes Radar Systems, we'll introduce you to people, ideas and jobs that could change your world. And maybe ours.

It could be you and Hughes

Radar Systems.

Call (213) 647-4900, collect, or send resume to:

Engineering Employment

Dept. B2

Hughes Aircraft Company

Radar Systems Group

P.O. Box 92426

Los Angeles, CA 90009

Current openings:

Software Design/Analysis Software Test Engineering Systems Integration & Test Computer-Aided Design &

Manufacturing RF/Microwave Design Digital Circuits Design & Test Radar Systems Design Large Scale Integration Design,

Development & Test Production Process Engineering Microprocessor Development/

Applications Antenna Systems Design & Test Reliability Engineering Production Test Engineering Industrial Engineering

HUGHES AIRCRAFT COMPANY

RADAR SYSTEMS

Proof of U.S. Citizenship Required Equal Opportunity Employer

252 BYTE February 1981

Circle 168 on inquiry card.

Product Review

The Heath H-14 Printer

Bradford E Rehm, 1004 Middle Cove Dr, Piano TX 75023

What this country needs is a good $250 printer. It ought to accept characters at 9600 bps (bits per second) and print them at 100 lines per minute. It should produce letter-quality print in various formats, including 80, 96, and 132 columns per page and 6, 8, or 10 lines per inch. It should have graphics capabilities, and it should offer an adjustable tractor-feed mechanism that can use narrow or wide paper. It should be very reliable, easy to service, quiet, and pleasing to look at.

Has Heath given us the Ail-American line printer? Perhaps not, but the folks in Benton Harbor, Michigan, have chalked up real accomplishments in several areas. As a $595 kit, the H-14 comes closer than any other 80-column impact printer on the market (at this writing) to meeting the price criterion. The somewhat higher "assembled" price still falls below most of its competitors' prices. And the H-14 does this while making a fine showing in the area of capabilities.

The H-14 Kit

The kit version of the printer is somewhat intimidating because of the sheer number of parts that emerge from the shipping carton. Rumors have been circulating to the effect that Heath had simply built electronics around an imported printer mechanism or that they had built a new enclosure around a familiar American-made mechanism which uses the Practical Automation dot-matrix print head. The truth is that while Heath uses the Practical Automation DM-101 print head, the rest of the mechanism (except, of course, for the driver motors) is of Heath's own design.

The builder, at any rate, assembles the printer mechanism from the very beginning. Happily, it is surprising to discover how easy the assembly is to execute, because, as always, Heath has done an outstanding job of preparing the kit manual. In fact, it is hard to believe that Heath charges $300 more for the assembled version.

There are few special parts in the mechanical portion of the printer. Two of the four shafts that operate the sprocket feed and support the print head, for example, are standard, quarter-inch extension shafts. This allows use of common quarter-inch bushings, collars, and grommets, which not only contributes to the low cost of the device, but also makes maintenance simpler.

Heath chose a more expensive route in providing a substantial die-cast metal base upon which the printer is built. It forms the lower half of the housing and supports the print-head mechanism, power transformer, and printed-circuit board. Although the molded plastic cover of the device is very light (why not, since it supports nothing), the metal base gives the H-14 the hefty, stayput feel of a heavy-duty piece of equipment.

The Electronic Circuitry

Nearly all of the parts in the electronics portion of the H-14 are mounted on two printed-circuit boards. The main board is busy but by no means crowded, and there are two extra LEDs (light-emitting diodes) available for checking logic functions as the integrated circuits are installed. The second, smaller board, which corrects a design oversight and which was not initially shipped with the kit (original shipment, February 1979), is mounted adjacent to the paper-drive motor.

The circuit is assembled on a double-sided, 12.5 by 25.5 cm (4% by 10y8 inch) board which includes the power-supply rectifier diodes, the printer-data-handling electronics, and the print-head and motor-driver circuits. The power-supply filters, a low-voltage regulator and a series-pass transistor, and an end-of-paper sensor are mounted off the board.

Because a microprocessor-controller is used, the circuitry is straightforward. Data enters and leaves the printer through a pair of EIA or 20 mA current-loop interfaces. These are connected to a UART (universal asynchronous receiver/transmitter) that provides the inter

Name

matrix, impact); ASCII

H-14

96-character set; 75

cps maximum print

Manufacturer

speed (40 cps average);

Heath Company

80-, 96-, or

Benton Harbor MI

132-column line width,

49022, (800) 253-0570

software selectable; ac

cepts 2V2- to 9 Vi -inch

Dimensions

wide paper, fan-folded

Height: 12.2 cm (43/«

sprocket-feed only

inches); Width: 46.5

cm (18% inches);

Software

Depth: 36.2 cm (1413/16

Requires H-8-14,

inches)

H-8-17, or H-8-18 soft

ware for use with

Price

Heath H-8 computer

$595 kit; $895

or HT-11 software for

assembled

use with Heath H-llA

computer

Features

Controlled by Fair

Hardware Options

child F8 microproces

Serial interface via

sor; uses Practical

RS-232 or 20 mA cur

Automation DM-101

rent loop, 110 to 4800

print head (5 by 7 dot

bps

February 1981 © BYTE Publications Inc 253

Circle 169 on inquiry card.

INTRODUCING THE LDP1 8088 MAINFRAME

Want to move to the new 16 bit generation of micro's? You do not want to assemble a system from board products? Finally, a complete system that only needs a Video Terminal plugged in to be on the air.

The LDP1 will get you going with your 16 bit systems quickly while not obsoleting other boards in your system. The LDP1 is a 16 bit system based on the LDP88, 8088 CPU board and the LDP72. advanced floppy disk controller. In addition you get 64 K of RAM, an 8" floppy disk, a mainframe with power supply and your choice of two different operating systems. All this for the unbelievable price of $3499 (with 86-DOS). And to make a good deal better, if ordered before February 28th, you pay only $2995 (with 86-DOS).

PRICES

BEFORE FEB. 28

LDP1 with 86-DOS

$3499

$2995

LDP1 with CP/M-86

3599

3099

Kit

Assembled & Tested

LDP88

$349.95

$399.99

LDP72

219.95

274.95

S100 Prototype Board

29.95

86-DOS

195.00

CP/M-86

250.00

Microsoft Basic 86

500.00

86-DOS required

350.00

with LDP1 and 86-DOS

PASCAL/M

250.00

CP/M-86 required

Rev. A LDP88's while they last $275

LOMAS DATA PRODUCTS

11 Cross Street

Wostborough, MA 01581 Telephone (617) 366-4335

PA5CAL/M is a trademark 01 Sorcim CP/M-86 is a trademark of Digital Research B6-DOS is a trademark ol Seattle Computer Products

LINE VOLTAGE TRANSIENT CLIPPING

Features Parallel Operation

PROTECTS:

•Computers

• Micro-Computer Systems •Word Processors •Cash Registers

• Power Supplies

5000 Hits/Second

PROTECTS AGAINST:

• High Energy Voltage Transients

•On-Off Switching •Lightning Induced Transients

• Inrush of On/Off Power

>Yma

Nj INDUSTRI

DV/MARC

INDUSTRIES, INC.

TRANSIENT VOLTAGE SURGE SUPPRESSOR

B7BF

®

(formerly PDF)

7133 Rutherford Rd. , (301)29^3130

Baltimore, Md. 21207 800-638-9098 ^

face between the serial communication lines and the parallel data bus of the microprocessor. The latter is a descendant of Fairchild's F8 family and includes on-chip read-only memory. This custom-masked device holds the program which enables the microprocessor to operate the printer. Data storage and address latching (which helps the processor interleave I/O [input/output] and printing tasks) are handled by a pair of 2112 memory devices and a 74LS273 8-bit latch. The processor also has four 8-bit I/O ports which are used as follows: two drive the seven print-head solenoids, the head-drive motor, the ribbondrive motor, and the paper-drive stepper motor; another does I/O to the UART; and the remaining one selects the specific device which is being driven.

Two Interesting Circuit Details

Two other sections of the circuit merit attention. Asked about how Heath was able to make the Practical Automation print head operate at speeds in excess of 120 cps (characters per second) while other printers using the same head have been restricted to lower speeds, an engineer at Heath explained that the H-14 continually monitors the resistance of one of the head magnet coils. In light-duty printing, the coil temperature does not rise significantly. During long printing jobs or when using the compact 132-column print, the internal temperature will rise to the point at which the head could be damaged. The increased temperature also increases the resistance of the winding, however, so a simple bridge circuit, monitored by two op amps, is used to detect the change and briefly halt printing.

On learning about this trick, one wonders if the printer will spend most of its time cooling down after it reaches operating temperature. In practice, however, this arrangement works well. The H-14 printed eight to fifteen 80-column pages before pausing to cool. The number of pages it executes seems to depend mainly on the ambient air temperature and circulation. Heath has left a slot in the bottom plate to provide cooling air from below, which can exit through the paper-viewing slot in the top cover, so the Heath engineers clearly understand that air circulation affects throughput.

That large rectangular slot in the bottom plate, just below the print head, is surrounded by a row of small holes. Some H-14 owners will visualize a blower and bellows arrangement fastened to the bottom plate at a flange bolted at these holes. It is surprising that they are not there for that reason at all. Although the printer is not certified by the US Underwriters' Laboratories, it has been approved by the latter's Canadian counterpart. The row of holes is necessary so that the H-14 can pass a test in which flaming oil poured into the enclosure must be quenched as it exits from the ventilation slot on the bottom plate. (Isn't it good to know your H-14 can be used as a flaming-oil quencher!)

The number of pages which can be printed before the first cool-down pause is smaller, of course, when the 96or 132-column print format is selected. The duty cycle of the head is increased in these modes—laying down 96 characters in a line before taking a breath (while going to the next line starting position) is more taxing than printing only 80 characters before taking a line break. Nevertheless, the pauses the H-14 takes for head cooling are not long. Again, the time required depends upon the ambient air temperature, but I find that most pauses are on the

254 February 1981 © BYTE Publications Inc

Circle 170 on Inquiry card.

From Digital Research

The Best Gets Better

CP/M®, the industry standard, continues to expand, because your needs continue to expand.

CP/M-80™

For cost-effective computing on 8-bit Z-80, 8080 and 8085-based microcomputers, CP/M-80 gives you the widest variety of mature, specialized software products anywhere. CP/M-86™

For jobs that require more address space and increased computing resources, CP/M-86 provides the soft

ware power you need. CP/M-86 is enhanced to operate with Intel's new 16-bit 8086 and 8088 microprocessors, with all the qualities that have given CP/M industry-wide support. And there's more to come: MP/M™, our multi-programming monitor, and CP/NET™, our network operating system, and PL/1, now available for 8-bit machines, will soon be available for the 8086/8088 family. CP/M. It's available on over 250 types of computers. For a closer look, ask your dealer, your manufacturer, or Digital Research.

U.S.A.

DIGITAL RESEARCH

P.O. Box 579

801 Lighthouse Avenue

Pacific Grove, CA 93950

408-649-3896

TWX 910 360 5001

EUROPE

VECTOR INTERNATIONAL

Research Park

B-3030 Leuven

Belgium

32 (16) 20-24-96

Telex 26202 VECTOR

FAR EAST MICROSOFTWARE ASSOC.

102 Plasada

3-16-14 Minami Aoyama

Minato-ku

Tokyo 107, Japan

03-403-2120

Telex 2426875 MSA

IQ DJGJTflL RESEARCH*

Circle 171 on inquiry card.

BYTE February 1981 255

S-100 GRAPHICS

Unretouched photograph

• TEKTRONIX EMULATOR

• PRINTER INTERFACES

• CHARACTER GENERATOR

Designed to work with the CDL

DYNAMIC BLACKBOARD

High Resolution Graphics Interface

• 51 2 x 640 Matrix • High Speed • Gray tones and color

• Light pen • Fast delivery • 2-year field experience.

Send for brochure and data.

CAMBRIDGE DEVELOPMENT LABORATORY

36 Pleasant Street, Watertown, MA 02172 (617)926-0869

order of two to five seconds, and they occur, nominally, every two to five lines after an eight- to fifteen-page warm-up period.

How closely does the H-14 approach the thermal limits of the print head in this kind of operation? A call to Practical Automation in Shelton, Connecticut, yielded the information that the DM-101 head can be operated at 100 cps (characters per second) bidirectionally if sufficient forced-air cooling is available. Continuous bidirectional operation above 16.5 cps is not recommended without forced ventilation or other protection, and the maximum internal operating temperature of the head is 62° C.

Heath claims that the temperature threshold for the shutdown has been set at approximately 50° C, which is well within the Practical Automation specification. This suggests that the printer can be run for long periods without fear of overheating the head. If you should want to try this, by the way, you may want to make sure that the head nose bearing has adequate lubrication. There is a felt-pad oil retainer on the back of the unit which should normally be given a few drops of machine oil after running through five boxes of paper. Giving it a drop or two before printing a whole box nonstop would be prudent.

There is no way to directly lubricate the solenoidoperated wires that actually do the printing. As is true for most wire-matrix heads, the wires are continuously lubricated by ink in the ribbon. This means that if you intend to realize the full, 100-million-character life of the H-14's head, you will never want to run the printer with a dry ribbon or without paper. You will also want to use only nylon ribbons, since cloth ribbons are easily perforated by the head wires.

Practical Automation recommends that nylon ribbons containing oil-based ink be used. A Heath representative that I contacted could not confirm that the officeequipment-type ribbon Heath supplies contains an oilbased ink. Testing at Heath has shown, however, that maximum head life is possible with its ribbons. (The manufacturer of one of the leading brands of ribbons available in office-supply stores was also contacted in an attempt to learn whether the ink used in these products is oil-based. In spite of the best efforts of the company's Dallas office, we were not able to acquire the information.)

The other interesting circuit is the driver for the paperfeed motor. There was a note in the original instruction manual for the H-14 saying that Heath would provide, upon request, a modification kit to enable the printer to more reliably lift paper from a box placed on the floor below it. The problem addressed occasionally appeared when my H-14 was required to lift 20-pound paper. The paper-drive stepper motor would occasionally growl and feed the paper in fractional-line increments instead of a full line.

The original stepper drivers used 7416 open-collector inverter/buffer devices to interface the microprocessor port to transistors that switched the motor on and off. One side of each winding was pulled high by a 12 V supply, while the other was pulled low by a transistor. A step was executed by turning off a pair of transistors. The problem was that the motor did not develop enough torque with a 12 V supply, but a higher voltage would probably have overheated it (stepper motors consume

256 February 1981 © BYTE Publications Inc

Circle 172 on Inquiry card.

DYNACOMP

Quality software for :

ATARI

PET

APPLE II Plus

TRS-80 (Level II)* NORTH STAR CP/M 8" Disk

GAMES, SIMULATIONS and EDUCATION

BRIDGE 2.0 (Available for all computers)

Prke: S17.95 Cassette 121.95 Diskette

An all-inclusive version of this mosl popular of card games. This program both BIDS and PLAYS eilhci contract or duplicate bridge. Depending on the contract, your computer opponents will either play the offense OR defense. If you bid loo high, the computer will double your contract! BRIDGE 2,0 provides challenging entertainment foi advanced playeis and 'isan eicellenl learning tool for the bridge novice.

HEARTS 1.5 (Available for all computers) Prke: $14.95 Cassette

$18.95 Diskette

An exciting and entertaining computet version or this populat card game. Hearts is a trick-oriented game in which the purpose is not to lake any hearts or the queen of spades. Play against two computer opponents who are atmed with hardto-beat playing strategies.

VALDEZ (Available for all computers) Price: S14.95 Cassette

$18.95 Diskette

A simulation of supertanker navigation in the Prince William Sound and Valdcz Narrows. The program uses an extensive 256X256 element radar map and employs physical models of ship response and tidal patterns. Chan your own course through ship and iceberg traffic. Any standard terminal may be used for display.

FLIGHT SIMULATOR (Available for all computers)

Price: S17.95 Cassette S21.95 Diskette

:malicat simulation of take-off, flight and landing. The program utilizes aerodynamic equaf a rial airfoil. You can practice instrument approaches and navigation using radials and compass headings. The more advanced flyer can also perform loops, half-rolls and similar acrobatic maneuvers.

CR1BBAGE 2.0 (TRS-80 only) Prke:S14.95 Cassette

S18.95 Diskette This is a well-designed and nicely executed two-handed version of the classic card game, cribbagc. It is an excellent program for the cribbagc player in search of a worthy opponent as well as the beginner wishing to learn the game, in particular the scoring and jargon. The standard cribbagc score board is continually shown at the top of the display (utilising the TRS-BO's graphics capabilities), with the cards shown underneath. The computer automatically scores and also an

CHESS MASTER (North Star and TRS-80 only) Prke:S19.95Cassc((e

523.95 Diskette This complete and vciy powerful program provides live levels of play. It includes castling, en passant captures and the ptomolion of pawns. Additionally, the board may be preset before the start of play, permitting the examination of "book" plays. To maximize execution speed, the program is written in assembly language Iby SOFTWARE SPECIALISTS of California). Full graphics ate employed in thcTRS-80 vetsion. and two widths of alphanumeric display todate North Star users.

STARTREK 3.2 (Available for all computers)

Prke: S 9.95 Cassette S13.95 Diskette

This is the classic Starlrek simulation, but with several new features. For example, the Klingons now shoot at the Enterprise without warning while also attacking starbases in olhet quadiants. The Klingons also attack with both light and heavy cruisers and move when shot at! The situation is hectic when the Enterprise is besieged by three heavy cruisers and a starbasc S.O.S. is received! The Klingons gel even!

SPACE TILT (Apple only) Prke: $10.95 Cassette

S14.95 Diskette

Use the game paddles lo till the plane of the TV screen to "roll" a ball into a hole in the screen. Sound s'trnpt? Not when the hole gels smaller and smaller! A built-in timer allows you lo measure your skill against others in this habit-rorming ac

GAMES PACK I and GAMES PACK II Price: S 9.95 each, Cassette

$13.95 each. Diskette GAMES PACK 1 contains BLACKJACK. LUNAR LANDER, CRAPS, HORSERACE. SWITCH and more. GAMES PACK II includes CRAZY EIGHTS. JOTTO. ACEY-DUCEY. LIFE, WUMPUS and others. Available for all corn

Why pay 15.95 or more per program when yoi

STUD POKER (ATARI only)

a DYNACOMP collection for just S9.95?

IIV

Price: Sll.95Cassetle

S15.95 Diskette

the classic gambler's card game. The computer deals the cards one al a lime and you (and the computer) bet on >u see. The computer does not cheat and usually bcls the odds. However, it sometimes bluffs! Also included is a d draw poker betting practice program. This package will run on a 16K ATARI. Color, graphics, sound.

NOMINOES JIGSAW (TRS-80 only) PricesS16.95Cassette

SZ0.95 Diskette NOMINOES JIGSAW is an intriguing and sophisticated graphical puzzle. The jigsaw consists of a 9 by 9 board partially tilled with randomly chosen shapes (nominocs), of which there are 60 types. By knowing lhal the shapes must be legally connected, and by guessing thcshapeal each location, all the nominocs maybe eventually deduced. Scoring is based on the number of guesses required and the difficulty of the board set-up.

MOVING MAZE (Apple only) Price: S10.95Cassette

S14.95 Diskette

MOVING MAZE employs the games paddles to direct a puck from one side of a maze I o the other. However, the maze is dynamically (and randomly) built and is continually being modified. The objective is to cross the maze without touching (or being hit by) a wall. Scoring is by an elapsed lime indicator, and three levels of play are provided.

BLACK HOLE (Apple only)

This is an exciting graphical simulation of the probli

Price: S14.95 Cassette S18.95 Diskette

ed in closely observing a black hole with a space probe. The

he anomaly lhal ihe lidal stress destroys ihe probe. Control or the craft is realistically simulated using side and main ihruslers for acceleration. This program employs Hi-Res graphics and is educational as well as

challenging.

TEACHER'S PET I (Available for all computers)

This is the first of DYNACOMP's educational packages. Primal provides ihe young student with counting practice, letter-word

Price: S 9.95 Cassette 513.95 Diskette

intended for pre-school lo grade 3. TEACHER'S PET lognilion and three levels of math skill e:

CRYSTALSIATARl only)

are built. No iwo patterns are ihe same, and has been used in local stores lo demonslral

PrlcetS 9.95 Cassette S13.95 Diskette

ing, graphics displays accompany with tones which vary as the patterns ombined effect of the sound and graphics are mesmerizing. CRYSTALS

r feaiu

of ihe

POKER PARTY (Available for all computers)

Price: 517.95 Cassette $21.95 Diskette

POKER PARTY is a draw poker simulation based on ihe book, POKER, by Oswald Jacoby. This is the mosl comprehensive version available Tor micro compulcrs. The party consists of yourself and six other {computer) players. Each of these players (you will gel lo know them I has a different personality in ihe form of a varying propensity to bluff or hold under pressure. Practice with POKER PARTY before going lo thai expensive game lonite!

Availability

DYNACOMP soFlwarc is supplied with complete documentation containing clear explanations and examples. All programs will run within I6K program memory space (ATARI requires 24K). Except where noted, programs are available on ATARI. PET, TRS-80 (Level II) and Apple (Applesoft) cassette and diskette as well as North Slar single density (double density compatible) diskette. Additionally, mosl programs can be obtained on standard (IBM formal) 8" CP/M Doppydisks for systems running under MBASIC.

' ATARI, PET, APPLE II, TRS-8Q. NORTH STAR, CP/M and IBM are registered trade n.

tnd/or trademarks.

BUSINESS, UTILITIES and MISCELLANEOUS

MAILLISTII (North Staronly) Prlcc:S21.95

This many-featured program now includes full alphabetic and zip code sorting as well as File merging. Enlries can be retrieved by user defined code, client name or Zip Code. The printout fo nal allows the use of standard size address labels. Each diskette can store more lhan 1100 entries (single density: over 2200 with double density systems!?

TEXT EDITOR I (Letter Writer)

An easy lo use, line-Oliemed text edilot editor is ideally suiled for composing le

Prke: S14.95 Cassette 518.95 Diskette

which provides variable line widths and simple paragraph indexing. This ted lers and is quite capable of handling much larger jobs. Available for all com

PERSONAL FINANCE SYSTEM (ATARI only) Prke: 534.95 Diskette

PFS is a single disk menu oriented system composed of 10 programs designed to organ ue and simplify your personal finances. Features include a 300 transaction capacity; fasl access; 26 optional user codes; dala retrieval by month, code or payee; optional printing of reports', checkbook balancing; bar graph plotting and more. Also provides on the diskette is ATARI DOS 2.

F1NDIT (North Star only) Prke:S19.95

This is a three-in-one program which maintains information accessible by keywords of three types: Personal (eg: lasl name). Commercial (eg: plumbers) and Reference (eg: magazine articles, record albums, etc). In addition lo keyword searches, ihere are birthday, anniversary and appo uilment searches for ihe personal records and appointment searches for the commercial records. Reference records are accessed by a single keyword or by cross-referencing iwo or three

DF1LE (North Slar only) Prke: $19.95

"1 his handy program allows North Star users lo maintain a specialized data base of all Tiles and programs in the stack of disks which invariably accumulates. DF1LE is easy lo set up and use. It will organize your disks to provide efficient locating of the desired file or program.

COMPARE (North Star only) price: S12.95

COMPARE is a single disk utility software package which compares two BASIC programs and d tplays the file sizes of the programs in bytes, the lengths in lerms of ihe number of statement lines, and the line numbers at which various listed differences occur. COMPARE permits ihe user lo examine versions of his software to verify which are the more current, and to clearly identify the changes made during development.

COMPRESS (North Star only)

COMPRESS is a single-disk utility program which rente from North Slar BASIC programs. The source file is pro

Price! $12.93

:csand (optionally) REM :d one line al a time, ihus permitting very large progra Bry, Tile compressions of 20-50*. are commonly achii

GRAF1X (TRS-80 only)

This unique program allow

Price: S12.95Cassette 51*5.95 Diskette

asily create graphics directly from the keyboard. You "draw" your figure using the program's extensive cursor controls. Once ihe figure is made, il is automatically appended lo your BASIC program as a siring variable. Draw a "happy race", call il HI and ihen print il from your program using PRINT HI! This is a very easy

TIDY (TRS-80 only) Prke: S10.95Cassette

S14.95 Diskette TIDY is an assembly language program which allows you to renumber the lines in your BASIC programs. TIDY also removes unnecessary spaces and REMark statements. The rcsull is a compacted BASIC program which uses much less mcmoiy space and executes significantly faster. Once loaded. TIDY remains in memory; you may toad any number of BASIC programs wiihoul having to reload TIDY!

NORTHSTAR SOFTWARE EXCHANGE (NSSE) LIBRARY PrkeS9.95 Diskette

DYNACOMP now distributes the >u+ volume NSSE library. Most of these diskettes ofTer an outstanding value for the purchase price. Write for details regarding ihe contents of ihis library and quantity (four or more) purchases.

STATISTICS and ENGINEERING

DATA SMOOTHER (Not available for ATARI)

This special dala smoothing program may be used lo rapidly derive useful information fior ingdata which are equally spaced. The software features choice in degree and range of Til, second derivative calculation. Also included isaulomatic plotting of Ihe inpul data and si

FOURIER ANALYZER (Available for all computers)

■other

Price: S14.95 Cassette 518.95 Diskette

ihe frequency spectra of limited duration signals. The program features automatic scaling and results. Practical applications include the analysis of complicated patterns in such fields

TFA (Transfer Function Analyzer)

and Filters by examining their response lo pulsed inputs. TFA is a maj contains an engineering-oriented decibel vetsus log-frequency plot as * ANALYZER is designed for educational and scientific use. TFA is an

HARMONIC ANALYZER (Available for all computers)

Prke: S19.95 Cassette S23.95 Diskette

ions of systems such as hi-fi amplifiers ilion of FOURIER ANALYZER and editing features. Whereas FOURIER g tool. Available for all compulcrs.

Price: 524.95 Cassette S28.9S Diskette

HARMONIC ANALYZER was designed for the spectrum analysis of repetitive waveforms. Features include dala file generation, edilingand storage/retrieval as well as data and spectrum plotting. One particularly unique facility is that ihe inpul dala need not be equally spaced or in order. The original data is sorted and a cubic spline interpolation is used to create the dala file required by the FFT algorithm.

FOURIER ANALYZER, TFA and HARMONIC ANALZYER may be pruchased together for a combined price of 144.95 (three cassettes) and $36.95 (three diskettes).

Prke: 519.95 Cassette SZ3.95 Diskette versatile one-dimensional least squares "polynomial" curve filling pro ■ utomatic degree determination option; an extensive internal library of fitI curve plotting; a statistical analysis (eg: standard deviation, correlation icw fits may be tried without reentering the data. REGRESSION I is cer.lysis software library.

REGRESSION I (Available for aU computers)

-yhigha

optionally

REGRESSION I is gram. Features inch ling functions; dala editing; coefficient, etc.) and much n la'inly ihecornersloneprogr,

REGRESSION II (PARAFIT) (Available for all computers)

polynomial filling, and PARAFIT Tor iht

REGRESSION 1 and 11 may be purchased together for £36.95 (<

Prke: S19.95 Cassette 523.95 Diskette

s in which (he parameters are imbedded (possibly nonlineaily) in the fitting inalform. including the parameters (A(l). A(2). etc.) as one or more BASIC lanipulated and plotted as with REGRESSION I. Use REGRESSION I for c complicated functions.

;)and $44.91 (diskettes)

BASIC SCIENTIFIC SUBROUTINES, Volume I (Not available for ATARI)

DYNACOMP is lhc exclusive distributor for ihe software keyed to the text BASIC Scientific Subroutines. Volume /by F. Ruckdeschel (see lhc BYTE/McGraw-Hill advertisement in BYTE magazine, January 1981). These subroutines have been assembled according lo chapter. Included with each collection is a menu program which selects and demonstrates each

Collection l\: Chapters 2 and 3: Dala and function plotting, complex variables Collection #2 Chapter 4: Matrix and veclor operations

Collection Ki: Chapters 5 and 6; Random number generators, series approximations Price per collection: 114.95 Casselle JI8.95 Diskette All three collections are available Tor $19.95 (three cassettes) and $49.95 (ihree diskettes).

Because ihe lexl is a vital pan of ihe documentation, BASIC Scientific Subroutines. Volume I is available from DYNACOMP for 119.95 plus 75; postage and handling.

Circle 173 on inquiry card.

Ordering Information

All orders are processed and shipped postpaid within 48 hours. Please enclose mation. If paying by VISA 01 Master Card, include all numbers on card. For t p~u.ga.nd handling.

Add 12.50 10 diskette price Tor 8" floppy disk (IBM formal soft sectored, CP/M, Microsoft BASIC) •TRS-80 diskettes arc nol supplied with DOS or BASIC.

Deduct 10% when ordering 3 or more programs.

ler. Write for detailed descriptions of these and other program

DYNACOMP, Inc.

6 Rippingale Road

Pittsford, New York 14534

(716) 586-7579

New York State reildcnli pleu, idd 7 » NYS ,,le, IM

Circle 174 on Inquiry card.

r

AT LAST!

Mass production prices (or high quality software. Buy direct and save 50%. Also available tor CPM and HDOS.

DATA BASE MANAGER Mod I & III S69. S149 (48K), Mod II S199

Maintain a data base and produce reports, all without user programming. Define tile parameters and report formats on-line. Key random access, fast multi-key sort, field arithmetics, audit log, label. No time-consuming overlays. 500 happy user-s in one year. Mod-ll and 48K versions have over50enhancements. including 40 fields maximum. IDM-M2 is great!' - 80-US.

A/R Mod-IS69 Mod-ll S149 Mod-Ill S69

Handles invoices, statements, aging, sales analysis, credit checking, forms input, and order entry. Unlike other accounts receivable programs, ours can be used by doctors, store managers, etc.

WORD PROCESSOR S49

Centers, justifies, indents, and numbers pages. Mod-I version features upper/lower case without hardware modification! File merge option available.

MAILING LIST Mod I & III S59, S79 (48K). Mod-ll S99

The best1 Compare and be selective. Includes forms input. 5-digit selection code, zip code extension, sort on any field, and multiple labels. Who else offers a report writer and merges with word processor?

INVENTORY Mod I & III S89, S109 (48K) Mod-ll S149

Fast key random access. Reports include order info, performance summary, EOQ and user-specified reports Many people have converted to our system! Next to impossible to damage the file.''

GL. A/R. A/P. PAYROLL Mod-ll S129 each

Integrated accounting package 100* page manual As opposed to Osborne's slow binary search and 64 column screen, we use fast ISAM and 80columns. Dual disk and TRSDOS required.

L21B S59

A cassette package of 10 business programs for Level I116 K systems. Includes word processor and data base manager. Poker game S19.

Most programs are on-line, interactive, random-access, bug-free, documented, and delivered on disks. Mod-I programs require32K TRSDOS. Were »1 in business software—don't let our low price fool you! Ask for our free 20-page catalog if you're still not convinced. Compiled versions are available.

fc*

MICRO ARCHITECT. INC.

96 Dothan St., Arlington, MA 02174

interactive video

• Provide a sophisticated teaching/training system or an audiovisual procedure manual

• Offer a comprehensive audio-visual database searchable by keyword

• Integrate interactive power of the computer with audiovisual impact of videotape using the same TV screen

• Use with Apple* or RS-232 computers, Sony or Panasonic VCR's

• Order in Applesoft or PASCAL, Choice of Authoring systems. Frame accurate stops and switches, no accumulated error

Cavil

SYSTEMS, INC.

26 Trumbull Street, New Haven, CT 06511 (203) 562-4979

*TM - Apple Computer Co.

B2/81

power even while they are not in motion). The solution required removing the motor-driver transistors from the main circuit board and adding a piggyback board at the motor.

The new circuit uses three 7486 two-input exclusiveOR gates and a flip-flop to determine whether the circuit is in the step or the hold mode. A diode and a pass transistor are added to determine whether 12 V or 35 V DC will be applied to the motor windings. The rest of the circuit is similar to the original, except for the addition of another set of inverter/drivers, which are necessary because the wiring to the motor-winding pairs has been reversed. In the hold mode, the diode feeds 12 V to the motor windings, enabling them to hold the feed mechanism at the current line. When a step signal arrives from the processor, the transistor is turned on (by the exclusive-OR gates and the flip-flop) and applies 35 V to the motor. In this way, the higher voltage is available for stepping, when maximum torque is needed. The rest of the time, the motor sees only 12 V, and its average power-dissipation limit is never exceeded.

Once again, Heath assures that this tactic, which coaxes superior performance from a conventional part, will not appreciably shorten its life. Thumb-and-indexfinger measurement confirms that the motor does not become appreciably hotter with the new driver than it did with the original one. Apparently, burning the candle at both ends works in this instance.

Configuring the H-14

When the printer has been assembled and tested, it is time to connect it to a computer and do some printing. As with most interfacing tasks, this one requires some planning. Heath chose to include a 256-character buffer in the H-14 so that, for example, a multitasking system could fill the buffer and go off to continue other tasks. To facilitate this kind of operation, the H-14 can accept serial ASCII (American Standard Code for Information Interchange) data at up to 4800 bps (110 to 4800 bps options are selected at a switch in the printer). Handshaking between the printer and the computer system can take place in either of two ways. When the buffer is empty, the H-14 sends an ASCII Control-Q (hexadecimal 11) on the return communication line to its host. When the buffer is full, a Control-S (hexadecimal 13) is transmitted. The computer software can therefore use these characters as signals to start or stop sending data.

The other handshaking option includes having the computer system look at the RTS (Request To Send) line from the printer. When the line buffer is empty, RTS is on (low), indicating that there is room for sixteen more characters; when it is full, RTS goes off.

I have already mentioned that the H-14 can provide variable line widths and line spacings. The 80-column and 132-column options can be selected by means of a push-button on the front panel. These and all the other options can also be obtained through software commands transmitted in the text. The sequence Escape/u/ Control-T, for example, switches the output from 80-column to 96-column format; an Escape/y sets the line spacing to 8; the Form Feed (hexadecimal OC) executes a carriage return and a form feed. The front panel also has Feed Forward and Feed Reverse buttons which can be used to position the print head at the top of a form, when the printer is switched off-line.

One option which will probably not be offered for the

258 February 1981 © BYTE Publications Ire

Circle 175 on Inquiry card.

THE PERFECT MARRIAGE

CHRISLIN 256KB MEMORY

minim i/i/i

iMk Ml itt ^^ *^L ^^ i^k |g^ m^ I 'MJ^f'*

bBBBbBbBB wLv

lllllllll

uu\\\\\\\v\\\\\\

DEC® LSI® 11/23

NOW AVAILABLE! 256KB memory on a dual height board only $1925. CHRISLIN INDUSTRIES now offers state-of-the-art 64K RAM Memory system designs. Like our recently introduced 512KB MULTIBUS® compatible single card memory our 256KB LSI 11/23 memory is an industry first.

Free up critical and expensive backplane space. Saves you 3 dual slots.

Addressable in 4K increments up to 4 Megabytes.

On board parity generator checker totally DEC hardware and software compatible.

Single 5 volt power requirement.

Battery back-up capability. 256KB unit draws less than 300 ma at 5 volts in battery back-up mode.

Tested and burned in. Full year warranty.

DON'T ASK WHY WE CHARGE SO LITTLE, ASK WHY THEY CHARGE SO MUCH.

«

Chrislin Industries, Inc.

Computer Products Division 31352 Via Colinas • Westlake Village, CA 91362 • 213-991-2254

Multibus is a trademark ohne Intel Corp tSI II is a trademark ol Digital Equipment Corp

Circle 176 on inquiry card.

BYTE February 1981 259

H-14 is an F8 processor with different programming to permit graphics printing. The reason is the lack of program and table space in the processor. Another consideration is that the paper movement is not reversible because of the H-14's rear paper inlet. One is tempted to try to feed the paper through the ventilation slot in the bottom plate of the enclosure—it is in just the right position below the print head and platen. An LED and photodiode are mounted in the normal feed path, however, to detect the out-of-paper condition. If the paper were brought in through the bottom of the cabinet, modifications to a paper guide would have to be made and the paper-detector feature would have to be sacrificed.

The Results

The print output of the H-14 is pleasing to the eye and easy to read, even when the 132-column format is used. The ribbon is canted a few degrees to minimize ink draining caused by the print head's covering the same area of the ribbon in repeated passes across the page. The ribbon can be canted further by shifting washers under its pulley. This gives additional protection from draining.

The spacing between the tractor-feed gears is adjustable, so that they can accept papers from 5.5 to 24.5 cm (2V2 to 9V2 inches) wide. Although I normally use 24.5 cm (9V2-inch) forms which can be burst to a 22 cm (8V2-inch) page, I have also used 22 cm multiform paper and 8 cm (3V2-inch) wide label forms. The H-14 handles the heavy labels very well, and it easily pulls 20-pound paper from a box on the floor, two feet below the feed inlet.

CURE TO

SOFTWARE

PROBLEMS

PROFESSIONAL SOFTWARE

Medical, Dental & Legal Systems, Accounting & Financial, Educational, Word Processing, Office Management

Check your Local Dealer or Contact:

Chofle/ fllonn & A//ociote/

7594 San Remo Trail

Yucca Valley, Ca. 92284

(714) 365-9718

Apple II

TRS-80

Tl 99/4

Is the H-14 the All-American Printer?

A number of new, inexpensive impact printers have entered the market since the H-14 was first advertised in January 1979. IDS, C Itoh, and Anadex are a few of the companies which have produced under-$1000 offerings with a variety of features. A buyer faced with the task of choosing among them will do well to check the performance specifications very closely. The H-14's need for cool-down time after printing ten or fifteen pages could be annoying in an office environment. On the other hand, some of the units that can print continuously may have no thermal overload protection and rely on the office air conditioning to keep things cool. Others have long duty cycles, but do not offer variable page and line widths.

The H-14 is a particularly good choice for the personalcomputer user because it not only performs well, but it should be inexpensive to maintain. It accepts a standard B-72 Teletype ribbon that can be purchased at most office supply stores for two or three dollars. If the kit is assembled, the buyer has a working knowledge of the construction of the unit and can probably repair mechanical faults which might develop. The excellent testing and troubleshooting guides included in each of the printer's two manuals cover most electrical problems.

Finally, there are Heath's own service and parts distribution facilities. Service is available in many cities at Heathkit stores, and parts are shipped from the factory within 24 hours of a telephone call, if a credit-card number is provided.

Parts are not expensive, by the way. The most expensive is the print head itself, which costs $133. The next dearest (excluding the power transformer) are the paperdrive motor and F8 microprocessor, priced at $15.95 and $14.90, respectively. Considering that a service contract for a commercial printer can cost in excess of $50 per month and that a service call to replace an ailing circuit board has been known to cost over $125, the H-14 should, indeed, be very economical to operate, even in the unlikely event that a part should fail.

The H-14 does not quite satisfy my criteria for the AllAmerican line printer, but it is certainly an excellent buy and, more important, a tough competitor for the title.■

A Public Service of This Magazine & The Advertising Council

Need help? Callus. ■£

CjOUKH

Red Cross counting on you.

260 February 1981 © BYTE Publications Inc

Circle 177 on inquiry card.

Is BASIC too SLOW?

OSBORNE/ McGraw-Hill's Assembly Language books help you speed up your programs

by Lance Leventhal

by Lance Leventhal

Assembly language programming is fast and efficient. For some applications, like computer animation or close control of peripherals, its speed makes it indispensable.

Now Osborne/McGraw-Hill helps to simplify assembly language programming. You needn't know anything about assembly language to use our ALP series. Each book is a straightforward, self-teaching textbook that is both concise and easy to understand. Each book explains assembly language programming, describes the function of assemblers, structured programming, and presents over 80 fully debugged practical programming examples.

Table of Contents:

Introduction to Assembly Language Programming Assemblers

The Assembly Language Instruction Set Simple Programs Simple Program Loops Character Coded Data Code Conversion Arithmetic Problems Tables and Lists Subroutines Input/Output Interrupts

Problem Definition and Program Design

by Lance Leventhal Adam Osborne Chuck Collins

Debugging and Testing Documentation and Redesign Sample Projects

by Lance Leventhal

by Lance Leventhal

h&>

Name.

Address.

City_ State.

.ZIP.

Phone.

HOW TO SHIP.

ef>.

OSBORNE/McGraw-HIII 630 Bancroft Way, Dept. B12 Berkeley, California 947lO

m

', *°ok

Price

Qty

Amount

':' 6809 Assembly Language Programming

-^- now available

Si 6.99

6502 Assembly Language Programming

516.99

ZBO Assembly Language Programming

516.99

68OO Assembly Language Programming

515.99

S080A/8085 Assembly Language Programming

515.99

ZSOOO Assembly Language Programming

519.99

The 8O86 Book

516.99

To order, return coupon with check or money Tax order. Include 75« per Item for 4th class mail, SI .25 per book UPS, or S2.50 per book air mail In the U. S. Shipping

California residents also Include local sales tax. ti-vtai To place an order by phone, call: 415/548-2805 TOTAL

1123

Circle 178 on inquiry card.

BYTE February 1981

261

Product Review

Zork, The Great Underground Empire

Bob Liddil, POB 66, Peterborough NH 03458

Deep within the inky underground Lurk things only half whispered of And twisty hidden passages Which hide both treasure and death. But who can deny the challenge Offered to he who would trespass here, For would not the lure of gold and glory Be worth more to a man than breath?

From Song of Zork by Freerover the Bard

Adventure has evolved many times during its short history. From Crowther's and Wood's creation to the genius of Scott Adams to the wild antics of Greg Hassett, the journey has been exciting and entertaining for the fans of inventive computer puzzles. No single advance in the science of Adventure has been as bold and exciting as the introduction of Personal Software Inc's Zork, The Great Underground Empire.

The first thing that everyone will look for when Zork boots up is the blinking cursor, and the "I AM..." and "YOU SEE..." format that Scott Adams has popularized in his nine Adventures. That is not the case here. The screen layout is arranged in such a way as to move the

Af a ninnro

Name

Language

Zork, The Great

Z80 machine code

Underground Empire

Computer

Radio Shack TRS-60

Type

Model I with 32 K

Adventure game

bytes of memory and

one disk drive

Manufacturer

Personal Software Inc

Documentation

1330 Bordeaux Dr

Printed instructions

Sunnyvale CA 94086

included

(408) 745-7841

Audience

Price

$39.95

Anyone interested in

Adventure or fantasy

gaming

Format

Backup Capability

5-inch floppy disk

None apparent

WHERE prompt (which gives your current location in the game) down to the bottom of the screen. I found this most useful after reading ten or twelve lines of detailed area description. Additionally, the number of turns elapsed, the number of points accumulated, and the location form an information display on the bottom line of the screen. Other game information scrolls upward as the game progresses, giving a very professional screen layout for the game.

If you happen not to have an unlimited amount of time to spend with your computer, Zork has a SAVE command that allows you to save your position in the game onto a blank, initialized floppy disk. While some cowards use it to retain their hard-earned position in the game before making some dangerous move, the true purpose of this command is to let you follow the game through to its ultimate end (which may take weeks), or as protection against losing your position due to, say, a brief power failure.

Zork comes on a write-protected single-density 5-inch disk with what appears to be its own operating system doing the booting and initialization. The disk defied examination by the most sophisticated methods available to me. I hope that Personal Software (which distributes Zork) will be able to foil the software pirates and traders for a while. The disk seems to be absolutely uncopyable.

Loading and preparing for play is simple enough. Merely insert the Zork disk into drive 0 and press the reset button of your computer. When the program is up and running, a pleasant block cursor greets you. You are now ready to play Zork.

Zork requires a 32 K-byte disk system (in this case, a Radio Shack TRS-80 Model I with 32 K bytes of memory and one disk drive) due to the eloquence of the descriptions and the large number of locations that are stored on the disk to be recalled at the appropriate times during the game. The advance copy I used had no instructions, so, in the beginning, I played a fairly straight game of Adventure.

I was eager to test Zork's biggest selling point, intelligent input (ie: its ability to accept free-form instructions). I typed "OPEN THE BAG AND GET THE LUNCH," in reference to a brown paper sack inside the house. The computer complied. There was water and food, so I typed "EAT THE LUNCH AND DRINK THE WATER," to which the computer responded with gratitude for satisfying its hunger and thirst.

I was hooked.

262 Febiuary 1981 © BYTE Publications Inc

QMEG A "WHOLESALE COMPUTER PRICES" sales DIRECT TO THE PUBLIC

co- 12 Meeting St., Cumberland, RI 02864

I lntcrtec Superbrainl 32K Ram - $2449 64K Ram • $2649

PRODUCT SPECIAL

of the MONTH!!

NEC spinwritcr 5510 5530 - $2449

Apple II- 16K$ 949 48K$1099

Diablo 630 H995

52195 (with tractor feed)

Products are

NOW

IN

STOCK

AT

OMEGA

Sales

Co.

Televideo , 912 B or C 920 C

»699| '7691

Centronics (limited quantitiescall for availability) 779-11 ' 749

704-9 '1500

730-3 » 599

737-1 ' 699

OMEGA OFFERS THE BEST DELIVERY AND PRICE ON: APPLE • ATARI • TRS-80 Model II • INTERTEC •

DIABLO • EPSON • HEWLETT-PACKARD • SOROC • COMMODORE • NEC • QUME • CENTRONICS

CALL TOLL FREE FOR OMEGA'S PRICE!

1-800-556-7586

OMEGA sells only quality merchandise to our customers. OMEGA will try to match any current advertised price with similar purchase conditions.

Before you buy anywhere else — be sure to call OMEGA Sales Co.

1-401-722-1027

OMEGA "A member in good standing of the better business bureau."

OMEGA ships via UPS, truck, or air. COD's. Visa, Mastercharge accepted, with no service charge.

Circle 179 on inquiry card.

BYTE February 1981

Exploring Zork

This Adventure begins in a beautiful forest near a large white house that is boarded up in an obvious attempt to keep explorers out. I managed to get into the house through the front once, but I was plunged into darkness and eaten by a monster called a grue. The game gave me the option of reincarnating myself, which I did (at a cost to myself of 10 points). I was revived in a forest.

Beyond the forest is a deep and beautiful canyon through which the River Frigid flows. This was the first time I had ever been at the end of the rainbow. No, I didn't see a pot of gold, but just because I didn't see it doesn't mean it wasn't there.

In these three locations (ie: house, forest, canyon), the descriptions were lavish, sparing no words in their bestowal of clues and information to the player. An ordinary jeweled treasure, in the form of a bird's egg, more than once sent me scurrying to the dictionary in search of the meanings of some of the words used to describe it.

There are many tools available to the explorer. I was able to obtain a lantern (light wards off grues), a length of rope, a nasty-looking knife, an elvish sword (which glows for reasons of its own), a refillable water bottle, a lunch, and garlic (which presumably repels Were-beings or Vampires, though I encountered none). Armed with these things, I entered the Underground Empire in search of gold and glory.

There was this pugnacious troll who popped up in the middle of a room description early in the game. Here, I got a chance to test thescombat capabilities of the game. I

Desk Main/Frame

Desk Main/Frame

LOW COST & ATTRACTIVE STYLING

• MAIN/FRAME INTEGRATED INTO FURNITURE QUALITY DESK

• ELECTRONICS PACKAGE SLIDE MOUNTED FOR EASY ACCESS

• SUPPORTS TWO 8" FLOPPY DRIVES FROM SEVERAL MANUFACTURERS (DRIVES NOT INCLUDED)

• 10 SLOT MOTHERBOARD INCLUDES CONNECTORS

• POWER SUPPLY FOR DRIVES AND CARDS

• DESK AND MAIN/FRAME AVAILABLE SEPARATELY

• MATCHING PRINTER DESK AVAILABLE

WRITE OR CALL FOR OUR BROCHURE WHICH INCLUDES OUR APPLICATION NOTE: 'BUILDING CHEAP COMPUTERS'

INTEGRAND

8474 Ave. 296 • Visalia, CA 93277 • (209) 733-9288 We accept BankAmericard/Visa and MasterCharge

typed "ATTACK TROLL", to which the computer supplied a supplemental <with hands>. Look out! Remembering that the program accepts more complex input, and, having survived the first combat turn, I typed "ATTACK TROLL WITH SWORD." This gave more satisfactory results: the troll expired, his body obligingly turning to black smoke in the interest of litter-free dungeon delving.

A thief came along shortly thereafter and challenged my right to exist in Zork. I typed "THROW KNIFE". He caught it in his sack and dispatched me to the netherworld, all in one swift motion. I could still hear him laughing as I lay ruefully reincarnated on the forest floor. I was ten points lighter and my possessions were scattered to the four winds. Sadder but wiser, I reentered the lower levels after 20 minutes of rounding up those items that were absolutely needed.

More cautious now, I explored the passages and tunnels of Zork (level 1). There are no unwarranted locations here—unless you can count the presence of a dam with color-coded control buttons in a maintenance room. Gleefully, I began pushing buttons, something I should know better than to do, as a veteran of the Death Dreadnought and Strange Odyssey Adventures. When the water level began rising, I was not concerned. Then I drowned.

The program was really getting testy with me by now. Grudgingly I was reincarnated by the Patron Deity who guards the souls of all Adventurers. Empty-handed once more, I resumed my journey. I retraced my steps to the Loud Room, where whatever you say is echoed. Then, after 768 turns and an afternoon of unparalleled enjoyment, my luck ran out. I became Grue Munchies, part of the balanced diet of silly dungeon players allotted to those carnivorous native dark dwellers of Zork.

On other occasions, I have been expelled from Zork on multiple charges of being a reckless Adventurer. Nonetheless, armed with the dubious rank of Amateur Explorer and my knowledge of the highest levels, I am looking forward to the time when I will plunge once more into the troll-, thief-, and grue-laden depths of the Underground Empire.

Zork, as peer to the Microsoft Adventure and heir apparent to the throngs of Adventure cultists who wait breathlessly for each new offering, is equal to the awesome task it has been given. That the program is entertaining, eloquent, witty, and precisely written is almost beside the point. Unlike the kingdoms of the Adventures for machines with 16 K bytes of memory and far from the classic counter-earthiness of the Colossal Cave in the original Adventure, Zork can be felt and touched— experienced, if you will—through the care and attention to detail the authors have rendered.

I've been to Zork today. Tomorrow, I will take a friend. Together we will unwrap the cloaks of mystery surrounding this most excellent and memorable work of computerized fiction. And when we have extracted from this land every drop of adventuring that can be obtained, we will likely not be kept waiting. A sequel is nearing completion, even as this is being written.

Somebody, please, let me know when it's done.H

264

February 1981 © BYTE Publications Inc

Circle 180 on inquiry card.

COMPUTING POWER FOR THE 80'S

8Mhz.

8086

WITH

MICROSOFT

BASIC

OPENS THE DOOR TO HIGHSPEED 16-BIT COMPUTING

BASIC-86

IT'S THE STANDARD — This BASIC is essentially identical to version 5 of Microsoft's BASIC interpreter, the accepted standard with widely available application programs. Programs distributed in CP/M® format are easily converted to the 86-DOS system. (CP/M is a registered trademark of Digital Research.)

IT'S FAST — It is two to seven times faster that BASIC-80 on a 4 Mhz. Z-80, depending upon application.

BREAKING THE 64K BARRIER — How many of you can run an extended disk BASIC and see the message "63309 Bytes free" when it signs on?

RUNS UNDER 86-DOS — Our high-performance operating system can load the 30K BASIC interpreter in less than 2 seconds. LOADing and SAVEing BASIC programs is done with similar speed.

8086 HARDWARE

MEMORY — Our two card 8086 CPU set is the only highperformance 16-bit processor for the S-100 bus that allows using standard 8-bit memories for economy or IEEE 16-bit memories for speed — in any mix.

16-BIT OR EXTENDED ADDRESSING — Special circuitry is included to allow memories without IEEE extended addressing to be used in systems with more than 64K (uses PHANTOM).

FAST 8 MHZ. OPERATION — Gives you high performance without requiring expensive memory. Most any 250 nsec. static memory board will do the job. Or, at the flip of a switch, a 4 Mhz. clock may be selected and/or a wait state may be added.

2-CARQ CPU SET — Includes serial I/O, parallel I/O, a monitor in 2716 EPROM, a time-of-day clock, and a very flexible and expandable vectored interrupt system.

86-DOSm

THIS HIGH-PERFORMANCE disk operating system provides a hardware-independent environment for running programs. By presenting a high-level interface for disk and peripheral I/O, the operating system relieves a considerable burden from the program.

DEVELOPMENT SOFTWARE — 86-DOS provides a complete package of development software, including editor, assembler,

debugger, Z80 to 8086 source code translator, and utilities

I/O CONFIGURATION — The hardware-dependent portions of the I/O system have been isolated into a single module. Full specifications are provided to allow customizing the module for a given hardware configuration.

From Seattle Computer, the System Design Experts

The products described here are only the beginning of a broad line of high-performance hardware and software products for the 80's. All of it is designed with "The Big Picture" — the total system — in mind.

For highest reliability, all of our hardware uses bus receivers which exceed the IEEE specifications by including

hysteresis. The system already includes complete hardware support for the multi-user superset of 86-DOS that will be released later this year. And our future products, such as a high-speed DMA controller for floppy and hard disks, will demonstrate an even further support for fast multi-user systems.

Prices: 8 Mhz. 2-card CPU set, fully assembled, tested, guaranteed, documented, 86-DOS included — $595; BASIC-86 — $350. Sale price ot $280 for 8/16 16-bit RAM ends March 1. Manuals for all SCP products may also be purchased separately. Overseas orders must be prepaid in US funds and include $10 per board for air shipment.

Circle 181 on inquiry card.

i Seattle Computer Products, Inc.

^f^ 1114 Industry Drive, Seattle, WA. 98188

(206) 575-1830

BYTE February 1981 265

Programming Quickies

Energy-Saving Cost/Benefit Analysis

Richard Hetherington

637 Pendleton Ave, Apt D

Chicopee MA 01020

The recent skyrocketing cost of energy makes us think of ways of conserving heat and saving money, whether by increased home insulation, using storm windows, lowering the thermostat, or any number of other methods. Cost versus benefit is always debated. How many times have you asked yourself: will the cost of adding 6 inches of insulation to the attic far outweigh the benefits?

In order to answer the cost/benefit question relating to home insulation, the mechanism of heat travel must be understood. I will briefly review the concepts of heat transfer, what influences it, and show how to use a BASIC program to make the cost/benefit decision.

Heat Transfer

Heat can travel between locations by any of three mechanisms: conduction, convection, or radiation.

Conduction is the flow of heat by molecular vibration and is usually associated with transfer through solids. For example, when a spoon is placed in a cup of hot coffee, the spoon gets hot by conduction of heat from the liquid.

Convection is the transport of heat through a fluid transporting medium by fluid movement caused by differences in density due to different temperatures, as when air picks up heat from a radiator in the home and distributes it throughout a room.

Radiation transports heat through electromagnetic energy, which is absorbed and converted to heat energy by a solid material. For instance, if you stand close to a blazing fireplace the radiant heat can become unbearable.

Heat can be lost from your home by all three mechanisms, but in most cases, the loss by conduction is most significant and is our main consideration.

The flow of heat from one place to another by steadystate conduction can be expressed by:

Q = TxA/R

where: Q = heat flow in BTU (British thermal

units)/hour T = temperature difference in °F (degrees

Fahrenheit)

A = area of heat flow in square feet R = resistance to heat flow in hour-square-feet- °F/BTU

The resistance to heat flow is related to the thickness of the material through which the heat is flowing, and the thermal conductivity (shown in table 1) of the material. For flat surfaces, it is found by:

R = L/K

where: L = thickness of material in inches

K = thermal conductivity of the material in BTU-inches/hour-square-feet-°F

If the heat is traveling through more than one material then R is expressed as:

R = U/K, + L2/K2 + L3/K3 + ...

where: Ll( L2, L3... = the thickness of each

material through which the heat flows Ki, K2, K3... = the thermal conductivity of each material

The R value can be calculated for any number of materials sandwiched together as long as the thickness and thermal conductivity of each material is known.

Looking at the formulas, you can see that the flow of heat depends on the temperature difference, the area it flows over, and the thickness and thermal conductivity of the material it flows through. Using these three formulas, you can readily calculate heat loss by conduction through flat surfaces.

Once the rate of heat loss is known, its cost can be calculated. Table 2 lists common fuels, the heating value of the fuel, and approximate cost of that fuel. The cost of the fuels will vary significantly depending on your location and the quantity purchased. For maximum accuracy, modify the fuel costs in table 2 to match the particulars of where you live.

266 February 1981 © BYTE Publications Inc

computer products, inc.

NEW LOCATION

1198 E. Willow Street

Signal Hill, CA 90806

(CALL COLLECT)

(213) 595-6431,6432,6433

ATARI 800

(NEW 16K VERSION)

'COMPUTER CONSOLE-OPERATORS MANUAL 'ATARI BASIC BK RAM »RF MODULATOR ■57 FULL STROKE -POWER SUPPLY

ALPHANUMERIC KEYS * ADDED OPTIONS PLUS 4 FUNCTION KEYS-JOYSTICKS ■INVITATION TO PRO- -EDUCATION ROM GRAMMING CASSETTE (NO CHARGE) CALL FOR PRICE 10% OFF SOFTWARE WITH PURCHASE

ATARI OPTIONAL ACCESSORIES

MODEL #810 DISK DRIVE SYSTEM MODEL #820 40-COL. DOT MATRIX PRINTER MODEL #822 40-COL. THERMAL PRINTER MODEL #825 80-COL. DOT MATRIX PRINTER MODEL #830 ACOUSTIC MODEM MODEL #850 INTERFACE MODULE MODEL #CX853 16K RAM MODULE

CALL FOR PRICE & AVAILABILITY

■'■■■■■Jammmmiswg&mi*&

. ■ ■

.- 'imps;.

MICROBYTE

% -Quad RS-232C Serial Pons. 1 20mA Currant Loop Porl

.JB|JJ'BBS:||-3

\ -Fully IEEE S-ICDBus Como I •Asynchronous Communical ■ wiln ZBOA Dflf|it«|orSyncri I Communications wilh Z80A j SlO/OilMI 5 'Full Sel ot Modem Conliol E

| includingRI (Ring Indicator)

yfeP

■■■■;■■

*■■ •';■:: ■■:;,: ■':■

I "I/O Servicing Environments: | 0) Polled; (2) Bus Vector; | (3) ZBOMOdBZ Vector f 'Oil.Board Inleirupl Daisy C

I/O Board $249.00 z^z.tzrJ:

Assembled & Tested :;r«",11™£""*"

single b

ird Z 60A CPU > proposed

•A compleli with 5cri.il/parnllcl mil

• Fully compahtile with IEEE S-100 Bus Standi

•Z-80A CPU (4MH; version of tho Z-flO) ■superselol and e from the BOSO's

•Up to 4K ol on board Eprom wilh Optional Z-flO monitor program — 1K(2708). 2K(2716)or 4K(2732)

• Full veclored inlorrupl capability —

MSB in

Z-80A/I-O $335.00

Assembled & Tested Optional Monitor Program $50.00

for e

', MREQ*. IOHQ*

a ROM

Dual FIS-232 serial I/O pons us lha Z80A-DART with Individual (from 50-19,200 or arallel I/O port—f p/Oflrammablfl Intel 8255A

•Up

ORDERING INFO

Name, address, phone,

Ship By: UPS or Mail

Shipping Chrg. Add $2.50 up to

5 lbs. (UPS Blue)

U.S. Mail Add $1.50 (U.S. Only)

($25.00 Minimum Order)

A-r An • SOFTWARE & A I AHI ACCESSORIES

BASKETBALL ROM $30.00

SUPER-BREAKOUT ROM $30.00 STAR RAIDERS ROM $45.00

CHESS ROM $30.00

VIDEO EASEL ROM $30.00

MUSIC COMPOSER ROM $45.00 3D TIC TAC TOE ROM $30.00

JOYSTICKS $18.00

PADDLE CONTROLS $18.00

#410CASSETTE RECORDER $60.00 ASK ABOUT NEW SOFTWARE

MICROBYTE

le ollliaan NEC765 LSI

■ ; '<:■.■■ ' • :

: i: = 1^ recovery Is, ,c:3lly re,

4 lllil

Disc Controller $349.00 :§|fff"""r

Assembled & Tested .s.„".V;cc''.",*pi,ir,,ae,,r,,,

64K RAM Board

Assembled & Tested

MICROBYTE

ully SlOObeis ; e':i::r.nelr

V Wltrl LED leal

Call lor Price

MHK=U.I=H

VERBATIM MD525-01 (SOFT) SCOTCH 744-0 (SOFT SECTOR) SCOTCH 744-10 (10 SECTOR) SCOTCH 744-16 (16 SECTOR) MEMOREX 3401 (SOFT SECTOR) SCOTCH 743-0(DS/DD SOFT)

l.'.M?ltM:H

LEEDEX 100, 12" B&W $129.00

LEEDEX 100-80, 80x24 B&W $165.00

SANYO VM4509, 9" B&W $175.00

SANYO VM5012, 12" B&W $240.00

SANYO DMC6013, 13" COLOR $450.00

HITACHI COLOR MONITOR $395.00

QUMEDT-8.DBL SIDED DBL DENSITY 8" DRIVE SHUGART SA801R DRIVE CABLES AVAILABLE CALL FOR PRICE

S.D. SYSTEMS

EnEnug

$27.50 CENTRONICS 737-1 $35.00 ANADEX DP8000 $3500 ANADEX DP9500 $25.00 ANADEX DP9501 $50.00 TEXAS INST 810 BASE 2 800 MST

CALL FOR PRICE

NOVATION CAT

300 BAUD, AUTO ANSWER/ACOUSTIC

$149.00 ea.

NOVATION D-CAT

300 BAUD/DIRECT CONNECT

$169.00 ea.

(OPTIONAL RS232 CABLE $22.00)

LIVERMORE

LIV-STAR 20M/300 BAUD

RS232, ACOUSTIC,

AUTO ANSWER, ETC.

$159.00

APPLE SOFTWARE

BY EDU-WARE

COMPU-MATH (FRACTIONS) $29.95

COMPU-MATH (DECIMALS) $29.95

COMPU-READ $19.95

EDU-PAK I, CONTAINS

COMPU-READ, PERCEPTION

STATISTICS $35.00

H?..H.W-1I.T,I3T¥1

MICROBYTE D2

<tO-|QC00 FLOPPY DISK SYSTEM ^^ ' SyJ

•(2) QUME DT-8, DMA S-100 CONTROLLER, POWER SUPPLY, CABINET, ASSEMBLED & TESTED WITH CABLE.

LESS CONTROLLER $1875°°

TERRORIST

WINDFALL

NETWORK

SPACE

PRISONER

$24.95 $16.95 $16.95 $24.95 $24.95

ALL SOFTWARE IS ON DISK.

PLEASE CALL IF YOU

HAVE ANY QUESTIONS.

EXPANDORAMI

2MHz DYNAMIC RAM BOARD

EXPANDORAM II

4 MHz DYNAMIC RAM BOARD

16K $230.00 32K $258.00 48K $286.00 64K $314.00

16K $245.00

32K $273.00

48K $301.00

64K $329.00

SBC-100 KIT $275.00

2.5 MHz/Z-80 CPU

WITH SERIAL & PARALLEL

I/O PORTS

SBC-200KIT $300.00

4 MHz/Z-80 CPU

WITH SERIAL & PARALLEL

I/O PORTS

VDB-8024 KIT $350.00

80x24 I/O MAPPED VIDEO BOARD WITH KEYBOARD I/O

S-100 PRODUCTS

VERSAFLOPPY I KIT $230.00

DISK CONTROLLER FOR 8" & 5%" DRIVES S-100 BUS COMPATIBLE

VERSAFLOPPY II KIT $330.00

NEW DOUBLE DENSITY DISK CONTROLLER FOR 8" & 5V." DRIVES

PROM-100KIT $190.00

S-100/EPROM PROGRAMMER FOR 2708, 2716, 2732, 2758 & 2516(TI)

ALL BOARDS ARE AVAILABLE

(ASSEMBLED & TESTED) CALL FOR PRICE & DELIVERY

(SYSTEM SOFTWARE) AVAILABLE UPON REQUEST)

CALIFORNIA COMPUTER SYSTEMS

MODEL 2016 2032 2065 2116 2200 2400 2422 2501 2710 2718 2720 2802 2810 5400 5416

16K STATIC RAM BRD.

32K STATIC RAM BRD.

64K DYNAMIC RAM BD.

16K STATIC RAM BD.

MAINFRAME

MINI-8100S

DISK CONTROLLER

MOTHERBOARD

4-PORT SERIAL I/O

2 SER. PORT & 2 PAR.

4-PORT PARALLEL I/O

6502 CPU BOARD

Z-80 CPU BOARD

MINI-8100

THE-8100

CALL FOR PRICE & DELIVERY

(SOFTWARE AVAILABLE)

TERMS

We Accept Cash, Check, Money

Orders, Visa & Master Charge

(U.S. Funds Only)

Tax: 6% Calif. Res.

COD'S & Terms Available on

Approval (School PO's Accepted)

4116's(200NS)

(APPLE, TRS-80, HEATH, ETC.)

8 for $30.00

16-49 pes. 3.60

50-99 pes. 3.40

100-499 pes. 3.25

500 Up 2.95

IJil[H:t»]J:CW=WiM:kH

8080A 2.50

Z80A 10.00

320T5 80

320T12 80

340T5 70

340T12 75

LO-PRO SOCKETS

14 PIN 16 PIN 18 PIN 20 PIN 24 PIN 28 PIN 40 PIN

1-99

.10 .12 .15 .23 .26 .30 .40

100 Up

.09 .11 .13 .21 .24 .28 .38

(BURNDY/TIN SOLDERTAIL)

RS-232 CONNECTORS

1-9 10-24 25 Up

DB25P 2.75 2.56 2.35 DB25S 3.80 3.70 3.60 Data Phone Hood$1.35ea.

COMPONENTS

74LS240 1.35 ea.

74LS241 1.25 ea.

74LS244 1.25ea.

74LS373 1.50 ea.

74LS374 1.50ea.

8T245 1.65ea.

2114 L-2/200 NS

1-16

$3.85 ea

17-49

$3.65 ea

50-99

$3.40 ea

100-499

$3.15 ea

500 Up

$2.95 ea

2708/450 NS

$6.25

ea.

or

8/$48.00

2716/5 VOLT

$10.00 ea.

(INTEL, TOSHIBA, ETC.) 100-Pc. Price $8.00 ea.

CAPACITORS

12 Volts Ceramic 90 ea.

OR 100/8.00

Circle 182 on inquiry card.

BYTE February 1981 267

Circle 183 on inquiry card.

MAIL ORDER DISCOUNTS

"apple computer

Sales and Service

APPLE II PLUS 48K

$999

APPLE #// CALL FOR PRICES

ACCESSORIES

DISK II DRIVE & CONTROLLER (DOS 3.3) 525

DISK II DRIVEONLY 420

INTEGER BASIC FIRMWARE CARD 149

APPLESOFT II FIRMWARE CARD 149

M&RSURR-MOD RF MODULATOR 30

CENTRONICS PRINTER INTERFACE CARD . .179

HIGHSPEED SERIAL INTERFACE CARD 139

LEEDEX VIDEO 100 12" B8.W MONITOR 139

290

MICROSOFT2-80SOFTCARO SYSTEM V1DEX 80 COLUMN BOARD

W/GRAPHICS AND SWITCH 350

HAYES MICROMODEM II 315

SILENTYPE PRINTER W/INT. CARD 495

LANGUAGE SYSTEM W/PASCAL 395

GRAPHICS TABLET 649

ALF MUSIC SYNTHESIZER 235

SOFTWARE

APPLE FORTRAN 159

PFSSOFTWARE 85

APPLE DOS TOOL KIT 65

APPLEPLOT GRAPH & PLOT SYSTEM 60

CCA DATA MANAGEMENT 85

515

THE CONTROLLER BUSINESS SYSTEM

THE CASHIER RETAIL MANAGEMENT 1B9

VIS1CALC 115

APPLEWRITER TEXT EDITOR 59

BASF5V*" DISKETTE(IO) 30

CALL FOR PRICES AND SELECTIONS OF PRINTERS AND MONITORS

TO ORDER: Please phone using VISA, Master Card and American Express. Or send cashier's check, money order or personal check {allow 10 business days lo clear). VISA and MC credit card service add 2%. AE credit card service add 5%.

Shipping, handling and insurance add 3% (minimum $3). California residents add 6% sales tax. Equipment is subject to price change and availability. All equipment carries factory warranty.

computer age. inc.

Authorized Apple Dealer & Service Center 4688 CONVOY ST., SUITE 105, SAN DIEGO, CA 92111 (714) 565-4042

-•" Clock/Calendar

CompvtefW atch

Now available on Three Buses

Features *APPLEII

• 12/24 Hr. Format

• Month-Day-Year

• Day of Week *TRS-80

• Leap Year Bit

• 4 Interrupts

• +-30Sec.Adjust\^>^

• Battery Backup 5^ QQ

• Simple to Program,

S I 50 FOB ' Apple is a Trademark of

Apple Computer Co.

COmpUTim© * TRS80 is a Trademark of Tandy Corp.

Dealer Inquire (714) 536-5000

P.O. Box 5343 Huntington Beach, CA 92646

Programming Quickies

Thermal conductivity (K)

Material

BTU

inches/hour-square feet-°F

air (horizontal heat flow)

1.00

air (vertical heat flow up)

1.20

aluminum

1400.00

asbestos cement board

5.16

asphalt

5.16

building brickwork

4.80

concrete

6.50

concrete block (6-inch)

6.60

copper

2700.00

corkboard

0.27

corrugated cardboard

0.44

dry sand

2.28

expanded vermiculite

0.48

fiberboard

0.34

fiberglass

0.25

granite

18.00

gypsum

3.00

ice

15.60

lead

240.00

masonite

0.33

macerated paper fill

0.28

mineral wool

0.27

paper

0.90

plaster

4.00

plywood

0.79

polyurethane foam

0.20

slate

10.30

snow

3.24

sawdust

0.41

styrofoam

0.31

water

4.30

window glass

5.00

white pine

1.04

wood shingles

1.15

Table 1: Thermal conductiv

ity (K) of common materials used

in construction and insulation. Note

that the K for air is

relatively constant for Vt-inch to 4-inc

h thicknesses. When

entering these values into

the BASIC

program shown in

listing 1, use the indicated figures for air (1.0 or 1.2)

regardless of the thickness

of the air

layer. (Data is from

various sources researched

by the auth

or.)

Fuel

L P gas hardwood electricity anthracite coal natural gas #2 fuel oil kerosene

Heating Value (H) Cost (Z)

21 ,000 BTU/lb 21,000,000 BTU/cord 3413 BTU/kW hr 12,700 BTU/lb 1050 BTU/cu ft 138,700 BTU/gal 135,500 BTU/gal

$0.245/lb

$100.00/cord

$0.055/kW hr

$0.04745/lb

$0.004845/cu ft

$0.93/gal

$0.97/gal

Table 2: The heating value in BTUs (British thermal units) and cost of various fuels commonly used for home heating. The indicated costs are local spot prices in western Massachusetts during the winter of 1979-80 and will vary significantly in different areas. For the greatest accuracy when using the BASIC program shown in listing 1, make sure the fuel costs are accurate for your area. (Data is from various sources researched by the author.)

The cost of heat lost is calculated by:

C = ZXQ/H

where: C = cost of heat lost in dollars/hour

Z = fuel cost in dollars/unit H = heating value of fuel in BTU/unit Q = heat flow in BTU/hour

268 February 1981 © BYTE Publications Inc

Circle 184 on Inquiry card.

MICROCONDUCTOR™

the ultimate data base manager t/s—_ for your TRS-80® and Apple® '299

The MICROCONDUCTOP.'" is nor jusr o file manager bur a true Dara Dose Managemenr Sysrem suirable for borh rhe novice and professional users.

DATA FILES —No limir on the number of records o file can have.

FIELDS—Any type (srring. inrerger. single, double). Eighr enrry modes (including defoulrs. counring, ond suppress). REPORTS—Four ways ro generare reports. Total numeric column(s). Print on any paper in any format (statements, labels, etc.). SORT—Any field(s) (i.e. mulriple-key sort). Any size file, numeric or ASCII. Ascending or descending. MAINT.—Commond anticipation. Record duplicarion, Direcr access ond sequenrial search. UPDATING/—Add, subtract, multiply, divide fields. Combine resulrs from MERGING previous calcularions. Tesr for any condirion ond roke action,

TRS-80® MODEL I s249

APPLE® $299

TRS-80® MODEL 11 >399

SAVE ON APPLE II 16K

FREE MEMORY UPGRADE KIT TO 46K WITH PURCHASE OF APPLE II 16K

>1195

INTRODUCTORY OFFER SAVE S300 LIST s949

Okidata Microline 80

$639

Model 82

$899

Patch for Apple Graphics '89

MTI APPLE 8" DISK SYSTEM

• One SA800R Floppy « M f\ f\

• 1 Drive Chassis b Power 5upply 9*1 A ^\%J

• Controller. Coble ond DOS I "T Vr/ *

SUP-R-MOD II s24.95

ADT KEY PADS s99.00

Z-80SofrCord '339

The Source MOO

Applesofrwore '29.95

SANYO MONITORS

9 inchQ/W '209

12 inchB/W '279.50

12 inch green phos... '309

10 inch color dara.... '470

MONTHLY

SPECIAL

SA801

DARE DRIVE

>469

Printers

Centranic700 '1,069

Base 2 '649

Centronics 737 '895

Centronics 702-9...'1,995

Malibu '2,093

Spinwrirer '2,569

Daisy Wheel '1,779

Anadex9500 M,549

A new enhanced NEWDOS for the TRS-80®

The most powerful Disk Operaring Sysrem for rhe TRS-80® designed forrhesophisricared user and professional programmer who demands rhe ultimate.

NEWDOS/80 is the planned upgrade from NEWDOS 2.1. Some of rhe fearures are:

• New BASIC commands for files wirh variable record lengths up ro 4095.

• Mix or march drives. Use 35, 40 or 80 rrack 5" disk drives or 8" disk drives, or combo.

• Security boor-up for BA5IC or machine code applicarion programs.

• New edirinq commands.

• Enhanced RENUMberrhar allows relocation.

• Command chaining.

• Device handling for rouring ro display and prinrer simulraneously.

• DFG function; striking of D. F and Gkeysallowsuserroenrer a mini-DOS wirhour disturbing program.

• Comparible wirh NEWDOS b TR5DOS.

• Machine language Superzap/80 2.1 uriliries $A A Q ad enhanced debug and copy. I" jt

Disk Drive Sale!

Complete with pawet supply and

chassis.

TF-3 5hugatt 5A400 '339

Perrec FD200, 40 ftack '379

• TF-5 MPI D51, 40 track '359

• TF-7Micropolis, 77 track ...'579 TDH-1 Duol sided,

35 rrack '469

TF-3M Drive 5ys 2 Shugarr.. '656

Disk Expansion System

• 2 Shugarr SA400 TF-3 '678

• 1 Twa-Drive Cable '26

• 1 Expansion interface 32K .. '459

• 1 35-rrock DOS+ '99

TOTAL LIST PRICE ....'1262

SPECIAL PRICE ONLY ....

$1,149

NEWD05+ 40 rrack '110

NEWDOS+ 3 5 track '99

D-Cor '199

Head Cleaner '19.95

AJA Business Pkg '359

The Source MOO

Dasic Compiler '195

Mail List '60

Elecrric pencil '150

NEW FOR

TF-8 80 TRACK DISK DRIVE by MPI

Double your capacity. Single head mini floppy. More than 200K byres of storage. Complete wirh power supply and chassis.

TRS-80®

TF-9 DUAL 80 TRACK DISK DRIVE by MPI

Quadruple your capacity. 400K byres of storage (like having 4-40 track drives in one unit). Complete with power supply and chassis.

*639

*789

• DARE DRIVES FOR ANY MICROCOMPUTER

Does nor include power supply b cabiner.

Perrec FD200 '262 FD250 '359

Shiqard5A400 35 rrack '269 5A410 40 track '279

MPIB51 '279 D52 '439

MPI B91 '399 B92 '525

fi»

/VIICROCO/VIPUrER

TECHNOLOGY INCORPORATED

Order Desk Only 800-554-7222 Telex #678401TAB IRIN

3304 W. MacArthur

Santa Ana, C A 92704

(714) 979-9923

ALL PRICES CASH DISCOUNTED

FREIGHT FOB FACTORY

ASK FOR FREE CATALOG

®Registeted Ttade Mark of Apple® ond Radio Shack

Circle 185 on inquiry card.

BYTE February 1961

269

Programming Quickies

Listing 1: A BASIC program for cost/benefit analysis of energysaving expenditures. Line 250 adds a constant factor to the resistance to heat flow (R) that takes into account externalsurface air-film resistance. This program is written in Processor Technology Extended Cassette BASIC and can easily be modified for other BASIC systems.

30 90 100 110 120 130 140 150 1.0 170 ISO 190 200 210 220 230 240 250 260 270 230 290 300 310 320 330 340 350 360 370 330 390

FOR LAYER ";I

THICKNESS <IN.>? ",L<I>

THERMAL CONDUCTIVITY (BTU.IN.'HR.SO.FT.DEG.F.>? ",K<I>

REM—SAUE MONEY BY INSULATING

REM—WRITTEN BY RICHARD E. HETHERINGTOM

REM—MARCH 1980

FOR J=l TO 2

PRINT "FOR CASE »";J

INPUT "AREA OF HEAT FLOW <SG.FT.>? ",A INPUT "INDOOR TEMPERATURE <DEG.F . >? ",T1 INPUT "OUTDOOR TEMPERATURE <DEG.F.>? ",T2 LET T-T1-T2

INPUT "HEATING UALUE OF FUEL USED <8TU.'UHIT>? INPUT "COST OF FUEL USED <*'UNIT>? ",Z PRINT "NUMBER OF LAYERS OF MATERIAL" INPUT "THROUGH WHICH THE HEAT FLOWS? ",K FOR 1=1 TO N PRINT PRINT INPUT INPUT NEXT I LET R«0 FOR 1 = 1 TO N

LET RCI>HL<t>'K<I) LET R=R*R(I> NEXT I LET R-R4-.5 LET Q<J>=T»A^R

LET c<j>=z*q<:jvh

PRINT

PRINT "HEAT LOST IS" PRINT "COST OF FUEL LOST IS";C<J) PRINT : PRINT : PRINT NEXT J

PRINT "HEAT SAUED CASE »2 OUER CASE HI IS" ; Q< 1 >-Q<2 > ; " BTU-'HR PERCENT OF HEAT SAUED IS"; < <Q< 1 >-<K2> VCK1 >>*1 00; " V COST SAVINGS IS";C<1)-C<2>;" *'HR." WHAT WILL BE THE C«ST TO YOU" TO HCHIEUE THIS SAUINGST ".E PRINT "PAYOUT PERIOD IS";E'<C<1>-C<2>>;" HOURS" END

; Q < T);" BTU^HR.

J.-HR.

PRINT PRINT PRINT INPUT

Another important consideration is the pay-out period. This is the length of time to recover any money spent on conserving energy through fuel savings. The pay-out period is:

P = E/(Cr-C2)

where: P = pay-out period in hours

E = cost to achieve the savings (in

dollars)

Ci= cost of heat lost before (in dollars

per hour)

C2 = cost of heat lost after (in dollars

per hour)

The pay-out period is the real indicator of whether you should spend the money. Generally, the shorter the payout period the better; however, under certain conditions pay-out periods as long as ten years may be acceptable. For example, it may take ten years to recover the cost of insulating the walls of your home. However, if it is a new home and you don't plan to move for a long time, then it will be worth it.

Listing 1 is a BASIC program that uses the equations to calculate the pay-out period and other information. The program is designed to compare two situations. Line 250 adds a constant factor to the resistance to heat flow (R) to take into account external-surface air-film resistance. This resistance becomes significant when considering materials with very low resistance to heat flow. The program is written in Processor Technology Extended Cassette BASIC.

One more thing: don't forget that you might be able to deduct money spent on energy conservation from your federal income taxlH

Problem 1

You have purchased a home that doesn't have any insulation in the attic, and you want to insulate it with 6 inches of fiberglass insulation. The attic is 20 by 25 feet (ie: 500 square feet). The ceiling below the attic is constructed of V2-inch pine boards (K = 1.04) and Vi inches of plaster (K=4). Average attic winter temperature is 40 °F and room temperature below the attic is 68 °F. The insulation will cost $110 for 500 square feet (K = 0.25). The house is heated with natural gas (H = 1050 BTU/cubic foot, Z = $0.004845 /cubic foot). You will do the work, so the only cost will be the insulation. Should you insulate the attic?

Solution

A 96% reduction in heat loss is indicated, and you will recover the money spent in 1970 hours (ie: 82 days) under the conditions given. Since this is less than one winter season, you should insulate.

Problem 2

You have a house identical to. the one described in Problem 1, except there already are 6 inches of insulation in the attic. Should you add 6 more inches of insulation?

Solution

By adding the insulation, you will save 49% of the heat presently lost. However the pay-out period is 87,469 hours. This is 3645 days (ie: thirty winter seasons). Under these conditions it's advisable not to spend the money.

Problem 3

Your house is well insulated but doesn't have any storm windows. There are twelve windows in the house, each 3 by 5 feet. (The total window area is 180 square feet.) Combination windows cost $35 each and will be installed by a contractor for a total cost of $600. (The total job cost is $1020.) The average outside winter temperature is 35 ° F, and the inside temperature is 72°F. The house is heated with electricity (H=3413 BTU/kW-hour, Z=$0.055/kW-hour). Should the combination windows be installed?

Material the heat passes through is:

Case 1: one layer of glass (L = 0.125 inches, K = 5) Case 2: two layers of glass (L = 0.125 inches each,

K = 5)

one layer of air (L = l inch, K = l)

Solution

There is a 66% reduction in heat lost through the windows. The cost savings is quite high at $0,135 per hour. But the installation cost is so high that the payout period is fairly long (about three winter seasons). The best plan would be to look for a cheaper contractor and then have the windows installed.

270 Februaiy 1981 © BYTE Publications Inc

Programming Quickies

A Variable Type Converter for Numerical Quantities

Mike Moskowitz, 23400 E Silsby, Beachwood OH 44122

Listing

\<A

?;a 33 n 3

50 ftfl 73

f?H 93

133 1 lfl

123

I 3f1

1 4*1 1 53 1 ft PI 1 7 3 1R3

1 93 P33 81 3

pp. 3 :?3 3

2 63

P73

PRM P93

3(10

313 393

3 3 3 343 3^3

3 63 37 3 3 8 PI 393 433 413 423

p P r* P40 2 ft 3

S T E P - 1

XM".\!

them

T M E M

X H E M P q [7

THEM 3 3''"

X H E M 3 o ri

XHEM 343

X H E \! 3 6 3

1: /I Hewlett-Packard BASIC program that converts string

R F. v< *l T '< E v| 3 S < 1W T X 2

RE"! COMVERTS STRIMG VARIABLES TO

I) I vi A[ S3 1 , R[ S'li , CC v^l , DC S3 1 . EC 53

A=C=D=E=3

B=1

A$=""

primx "'/"; t mp lit as

C = LEM ( A SO E03 o=c TO' 1 if Asrn»rn-"'v if- Asco,ni = "r

I F ASC l)# 01 = '*2' TE A$CD»riJ="3'

if A$rn, m ="/i

IF A£CD>D1='*5'

tf ASCD»m = "ft' ie Asm. m = "7"

IF A¥C0»m="8" THEM 3R3

TF ASC n. D] = "9" THEN] 433

33TO 413

E [ D 1 = 3

30X0 413

E C m = 1

30X0 413

E C D 1 = 2

GOTO 413

E C D1 = 3

30 TO 413

E C 3 1 = 4

30X0 413

ec m = s

GOTO 'H3

EC 01 = 6 GOTO 413 E C m = 7 GOTO 413 EC D1 = R GOTO 413 EC 01 = 9 A=A+ECD1 *3

B- B* 13 Listing 1 continued on page 272

variables to numeric variables.

v) 1 HEMIC VA'U Afll.ES 1 » A $ C 5 !.11

In most versions of BASIC, there are some operations and functions which can be performed only on alphanumeric (string) variables and not on numeric variables. Likewise, there are operations which will work only on numeric variables and not on strings. For example, most BASICs will accept operations such as these:

10 A = LEN(A$)

20 PRINT A$(l,l)

30 LETA = B*C

40 PRINT SQR(A)

But these statements are illegal in BASIC:

10 A = LEN(A)

20 PRINT A(l,l)

30 LET A$ = B$*C$

40 PRINT SQR(A$)

It would be convenient to have a subroutine which would convert numeric quantities stored in string variables into numeric variables, and vice versa. This would allow all numeric quantities to gain the use of both types of functions, regardless of the type of variable they were originally assigned to. This is an easy task in some of the newer, more powerful BASICs which allow access and manipulation of ASCII representations. Most BASIC systems, however, do not have this capability.

Listing 1 converts numbers from strings to numeric variables. This subroutine is invaluable when some number which must be operated on arithmetically is embedded in an input string. Listing 2 converts numbers from numeric variables into string variables. It allows numeric quantities to receive the use of operations such as substring selection, A$(X,Y), and the LEN function. These subroutines may be improved by modifying them to accommodate decimal points or scientific notation. These programs were written in BASIC on a HewlettPackard 2000E computer, and may need slight modifications, but will run on many microcomputer BASICs. ■

February 1981 © BYTE Publications Inc 271

Listing 1 continued:

430 me*t d

440 PRIMT A

4 50 P • <! T \l T

460 TOT") 30

473 EMD

Listing

1 0 20 3 0 40 50

60

70 Fid 100 1 10 120 131?) 1 40 1 50 1 60 1 70 1*0 1 90 200 210

2: A program that converts numeric variables to string variables.

RZV MTXE '■nSKOWIT'2.

REM CONVERTS NUMERIC VARIABLES TD STRIM

DIM AC50],3[501,C[5 0]>D[50]»X[501»A?C50

A=8=C=D=X~0

4$=""

A

VARIABLES.

= 0 THEM 120

PRIMT IMPUT B = B+ 1

IE IMTCA/1 0tB):

GOTO 80

EOR X=l TO B

DCX3 = C(A-I\lT(A/10TX)*10TX)-CA-TMT(A/10TCX-1))*10TCX-l)))/10TCX-n

MEXT X

C=l

EOR X=H TO 1 STEP -1

TP" DC X 1 = 0 THEM 2 70

IE

TE IE IE

D[X]=1 DCX]=2 DCX]=3 DCX1 = 4

THEM THEM THEM THEM

290 310 330

3 50

THE FORTH SOURCE

Specializing in printed material for the FORTH language. Send for listing of current material.

Installation Manual $10.00

8080 Listing $10.00

6502 Listing $10.00

6800 Listing $10.00

6809 Listing $10.00

PDP-11 Listing $10.00 more

Using FORTH, Manual $25.00 PDP-11 User's Guide $20.00 Kitt Peak Primer $25.00

more

Dealer Inquiries Invited.

Write for complete listing of FORTH material.

MOUNTAIN VIEW PRESS

PO Box 4656

Mt. View, CA 94040

220

IE DC X 1 = 5 THEM

37A

230

TE DCX] = 6 THEM

3 90

240

IE ncX1=7 THEM

410

2 50

IE DCX1=8 THEM

430

260

IE DC X1 = 9 THEM

4 50

27 0

A$CC*C1="0"

230

GOTO 460

290

ASCC*CI="1"

300

GOTO 460

310

ASCC*C]="2"

320

GOTO 460

330

A$CC>C1="3"

3 40

GOTO 460

3 50

A$CC>C1="4"

360

GOTO 460

370

A8[C*C]="5"

380

GOTO 460

3 90

ASCC>C] = ,,6"

400

GOTO 460

410

ASCC>C]="7M

420

GOTO 460

430

A$CC>C1="S"

4 40

GOTO 460

450

ASCC>C1="9"

460

C=C+1

470

MEXT X

4R0

PRTMT AS

490

PRIMT

500

GOTO 10

51 0

EMD

272 February 1981 © BYTE Publications Inc

Circle 186 on Inquiry card.

World Leader in Phonetic Voice Synthesis

Announces the Formation

of its New Sales Distribution Division

l/ODE\

To serve your specialized low-volume speech synthesizer needs.

PRODUCTS AVAILABLE NOW:

VOTRAX SPEECH PAC

$275.00

The Votrax Speech PAC (Phoneme Access Controller) provides a system designer with low cost, unlimited vocabulary speech synthesis. The small circuit board can be easily designed into systems and is suitable for experimentation and evaluation of phoneme-based speech synthesis. Operating in a handshaking mode with an external controller, up to 255 words can be accessed. Prestored words and phrases can be intermixed with phoneme sequencing to provide unlimited vocabulary. The Speech PAC includes these features: SC-01 Low Data Rate Speech Chip, expandable memory with the use of a 32 K EPROM, on board audio amplifier, parallel interface — TTL compatible.

VOTRAX VSM-1

The Votrax VSM-1 (Versatile Speech Module™) introduces a new high level of performance and flexibility for computer speech modules. The Speech Module is an extremely powerful audio response system designed to simulate or develop talking products.

Over 1300 stored words and a built-in prefix/suffix table provide a vocabulary of over several thousand words. Additionally, up to 8 K bytes of user vocabulary can be accommodated. Phoneme sequences can be easily intermixed with prestored words to generate unlimited vocabulary.

TO ORDER CALL TOLL FREE (800) 521-1350.

$1195.00

Speech rate and pitch can be dynamically programmed to develop stress patterns. Many voice effects are programmable using master clock frequency controls. A wide range of sound effects can be generated using prestored sound macros. Additional sound macros can be user defined. VSM-1 interfacing can be either parallel or serial (RS-232C). With selectable baud, a common computer terminal can be used to directly

UODEX

A VOTRAX COMPANY %^

create speech and sound effects. The VSM-1 operating system (voxOS,M) is 6800 series MPU based. voxOS may be bypassed or downloaded 6800 compatible segments may be executed to change system functions. Adding additional devices to the speech module is facilitated by an expansion bus connector.

SC-01 SPEECH SYNTHESIZER CHIP

Available in quantities 10 to 5000

The SC-01 Speech Synthesizer Chip is a self-contained, 22 pin CMOS device. The chip synthesizes continuous speech of unlimited vocabulary by combining phonemes (the building blocks of speech) in the appropriate sequence. The chip produces continuous speech from a 70 bit data rate. Included on the chip is an audio preamplifier. The SC-01 chip produces 64 phonemes which are accessed by a 6-bit code. Two additional input codes can be used to set an inflection level. An on-chip master clock circuit can be externally controlled to enhance voice quality and to provide a broad range of sound effects.

500 Stephenson Highway Troy, Michigan 48081 Phone: (313)588-0341

Circle 187 on inquiry card.

BYTE February 1981 273

Education Forum

Microcomputers in the Chemistry Laboratory

Robert P DeSieno, Director, Computer Services Center, Davidson College, Davidson NC 28036

Editor's Note: Since writing this article, Mr DeSieno has moved from Westminster College, New Wilmington, Pennsylvania, to his present post at Davidson College.

Photo Is An Altair 8800b microcomputer, floppy-disk drive, and Lear-Siegler ADM 3A terminal interfaced to a pH meter.

Photo 2: The graphics display presented by an RG-512 Retrographics card in the Lear-Siegler terminal. The Y axis is calibrated in units of pH, the X axis in milliliters of titrant. The plot is a titration curve for the reaction between sodium hydroxide and phosphoric acid.

The advances in microcircuitry, the production of solid-state components, and the development of microcomputers provide small chemistry departments with inexpensive resources for interfacing computers and laboratory instruments (see references 1 and 2). Marketed by a cottage industry that serves hobbyists, microcomputers and their peripheral devices offer faculty and students modern means to gather data, process information, and enrich their understanding of chemistry.

Equipment and Hardware

In the last three years, faculty and students in the Chemistry Department of Westminster College built from kits an Altair 8800b microcomputer, a Lear-Siegler ADM 3A terminal, 48 K bytes of dynamic memory, two serial ports, and four parallel ports. In addition, the department bought a graphics module (Digital Engineering RG-512 Retrographics card) for the Lear-Siegler terminal and a MITS 3200 disk drive. We assembled these components into a system (see figure 1 and photo 1) that samples the output of gas chromatographs, spectrophotometers, or pH meters, stores data on disks, calculates results, and displays information on a video terminal and a printer.

To change analog signals into digital information for the computer, we use a digital-panel meter (Analog Devices AD2010 DPM) that converts signals in the range ±199.9 mV into 3V2 binary coded decimal (BCD) numbers and displays the data transferred to the computer. We program a Motorola PC6820 Peripheral Interface Adapter (PIA) to handle two status bits and thirteen parallel-data bits transferred between the computer and the DPM. The DPM delivers data at controlled rates up to a maximum of 24 readings per second, a pace sufficiently rapid for many instrumental measurements of chemical behavior.

Laboratory Activity

To introduce techniques of interfacing, we guide upper-level students for four weeks while they use a microcomputer to study the rate of reaction between ferric and iodide ions and determine titration curves for reactions between acids and bases.

Students use an ultraviolet-visible spectrophotometer (Bausch & Lomb Spectronic 20) set at a wavelength of 425 nm (nanometers) to observe the increasing absorbance of light in a solution of ferric and iodide ions. Triiodide ions, a product of the reaction in solution, cause the growth of absorbance and the changing absorbance signal in the spectrophotometer reflects the rate of

274 February 1981 © BYTE Publications Inc

5,000,000 Reasons to replace your 5-inch Floppies with a low-cost, high-performance

TTT

5 megabytes instantly expand the program and data storage horizons on your H-89r TRS-80, or s-100 microcomputer system.

DJust slip 5 megabytes of on-line data storage Into place In your standard 5-Inch floppy disk openings, and suddenly your capability horizons have dramatically shifted, upwards, now your CP/M* s-100 microcomputer system, or H-89 Heathklt (HDOS or CPM 2.2) computer system can utilize the kind of hlgh-rellablllty and rapidaccess mass storage which today's sophisticated programming demands. DA company named act has created a complete package at a price so good, you couldn't walk away from It. The 5-Inch package Includes the remarkable Shugart Technology ST 506 hard-disk drive with 6.3 megabytes of unformatted mass storage and a micro-sequencing controller card with complete floppy disk-like Interfacing. Harddisks have never been more affordable, nif you are wondering Just how these ultra-fast, high throughput hard-disk drives will work with your multi-terminal or real-time, transaction oriented systems: now you can get some straight answers. Clip and mall the coupon for quick response to all your questions. Or better yet, give us a call today at (703) 471-6288 for some no-nonsense reasons why your system needs to act now. Quantity pricing Is available to meet the needs of Original Equipment! Manufacturers; check the box on the coupon.

Circle 189 on inquiry card.

Clip and mail coupon to:

American Computer 11301 Sunset Hills Road

and Telecommunications Suite A-4, Reston, VA 22090 Corporation 1,703)471-6288

Tell me more about the ACT 5-inch hard-disk drive package:

My present 5-inch hard-disk drive interests center around:

□ S-100 Microcomputer Systems

□ H-89 Heathkit Computer Systems

□ TRS-80 Radio Shack Computer Systems

□ Send me quantity price schedule

Name

Title

Company Address _

City, State, Zip Phone ( )

MICROCOMPUTER

VIDEO DISPLAY

DIGITAL DATA

DIGITAL

PANEL

METER

SIGNAL

OPERATIONAL

INSTRUMENT

AMPLIFIER

FOR IMPEDANCE CONTROL AND AMPLIFICATION

Figure 1: Block diagram for interfacing a laboratory instrument and a microcomputer.

this reaction. The absorbance signal is captured at the amplifier of the spectrophotometer and delivered through the DPM to a parallel port of the computer. To transfer data to the processor and calculate rate constants, exponents of terms, and energy of activation from their rate studies, students program the microcomputer in Extended Disk BASIC.

To trace the behavior of acid-base titrations, students use a combination glass and reference electrode to measure changing concentrations of protons in solution and deliver changing potential differences between these electrodes to a pH meter. A syringe driven by a pump delivers the base at a fixed rate into the acid to be titrated. A clock controlled by software coordinates the rate of travel for a vector across the video screen with the rate of delivery of base. The clock and the pH meter (by way of the DPM and a port) provide pairs of data needed to use the graphics terminal as an x,y plotter (see photo 2).

Educational Approach

These projects embody chemistry that our students have studied earlier in laboratories of lower-level courses. This earlier experience lends confidence to students and helps them concentrate more effectively on the details of interfacing. Students compare results from observations made with the aid of interfacing to results they obtained from earlier studies and to information reported in the literature. Such comparisons impress upon them the value of checking conclusions on the way to scientific understanding.

Students learn quickly that interfacing a microcomputer to a laboratory instrument requires comprehensive understanding of the work they will do. To attain their goals, they must:

• become familiar with the theory of the measurements they will make in order to write and test software that instructs the computer to calculate results and establish a format for reporting information

• connect the computer with the aid of appropriate hardware to the instrument

• use and test software that will control the transfer of information between the computer and the instrument (handshaking)

• prepare and standardize solutions required for the project

To help students develop the skills they will need, we assign exercises that familiarize them with our microcomputer, an instrument, and the details of interfacing these devices. We divide students into two groups: those who have programmed and those who have not.

Students who have programmed refresh their skills by programming with Extended Disk BASIC to calculate physical properties and chemical behavior of gases, liquids, solids, and solutions. We assign tutorials in computer-aided instruction to students who have had no programming experience and work closely with these students until they grasp the fundamental qualities of programming and can also use the computer to solve

Turn your Apple* inside out

Softbus" brings the Apple's bus to your workbench to be conveniently plugged into your breadboards. Don't let a drop of solder or coffee destroyyour computer. With the cover secured and Softbus, your Apple is safe, protected and accessiblefor easy circuitinterfacing. Softbus is the ideal, low cost design and interface tool for hobbyists, technicians and engineers. Write or give us a

call for details. _, .

,,^-,A-,n^A S X Suggested retail S80.00.

(415)747-0614 / \ Dealer inquiries invited.

^^9*^^ ^^0^*^ Mail orders accepted.

Tt^RASsport

-^DGSIGNS

s a registered trademark of Apple Computer, Inc. is a trademark of Passport Designs. Inc.

Marketing; Box 21061. Minneapolis. MN 55421

Headquarters: Box47B. La Honda, CA 94020

276 February 1981 © BYTE Publications Inc

Circle 190 on Inquiry card.

dBASE II vs. the Bilge Pumps.

byHalPawluk

We all know that bilge pumps suck.

And by now, we've found out—the hard way—that a lot of software seems to work the same way.

So I got pretty excited when I ran across dBASE II, an assembly-language relational Database Management System for CP/M. It works! And even a rank beginner like myself got it up and running the first time I sat down with it.

If you're looking for software to deal with your data, too, here are some tips that will help:

Tip #1: Database Management vs. File Handling:

Any list or collection of data is, loosely, a data base, but most of those "data base management" articles in the buzzbooks are really about file handling programs for specific applications. A real Database Management System gives you data and program independence (no reprogramming when data changes), eliminates data duplication and makes it easy to turn data into information.

Tip #2: Assembly Language vs. BASIC:

This one's easy: if you're setting up a DBMS, you're going to be doing a lot of sorting, and Basic sorts are s-l-o-w. Run a benchmark on a Basic system like S*-IV against a relational DBMS like dBASE II and you'll see what I mean. (But watch it: I've also seen one extremely slow assembly-language file management system.)

Tip #3: Relational vs. Hierarchal & Network DBMS.

CODASYL-like hierarchal and network systems, around since the 1960's, are being phased out on the big machines so why get stuck with an old-fashioned system for your micro? A relational DBMS like dBASE II eliminates the predefined sets, pointers and complex data structures of a CODASYL-type DBMS. And you don't need to be a programmer to use it.

dBASE II vs. everything else.

dBASE II really impressed me. Written in assembly language (with no need for a host language), it handles up to 65,000 records (up to 32 fields and 1000 bytes each), stores numeric data as packed strings so there are no roundoff errors, has a superfast multiple-key sort, and supports ISAM based on B* trees.

You can use it interactively with English-like commands (DISPLAY 10 PRODUCTS), or program it (so when you've set up the formats, your secretary can do the work). Its report generator and userdefinable full screen operations mean that you can even use your existing forms.

And if all this makes your mouth water, but you've already got all your data on a disk, that's okay: dBASE II reads your ASCII files and adds the data to its own database.

Right now, I'm using dBASE II with my word processor for budgeting, scheduling and preparing reports for my clients.

Next come job costing, time billing and accounting.

An Unheard-of Money-Back Guarantee.

dBASE II is the first software I've seen with a full money-back guarantee.

To check it out, just send $700 (plus tax in California) to Ashton-Tate, 3600 Wilshire Blvd., Suite 1510, Los Angeles, CA 90010. (213) 666-4409. Test dBASE II doing your jobs on your computer for 30 days. If, for some strange reason, you don't want to keep it, send it back and they'll refund your money.

No questions asked.

They know you don't need your bilge pumped.

AshtonTate

©Ashton-Tate 1980

Circle 191 on inquiry card.

BYTE February 1981

277

problems in chemistry. Eight to ten hours of programming on an interactive terminal, guidance from a teacher, and help from other students give all students the ability and confidence to use the computer for elementary interfacing operations.

To help students understand how information is transferred between the computer and an instrument, a process called input/output or I/O, we provide hard and disk copies of routines that manage I/O. Students study these routines and explore the relationships between hardware and the software that executes I/O. The students then embed their software for calculating results within these routines and synthesize a program that controls transfer of information among instrument, computer, and disk files, as well as presents results at the video terminal.

When students have completed these tasks, we provide sample data retrieved from disk files so they can simulate their experiments and test and correct their programs. Assured of hardware and software that work, students complete their lab work by selecting substances and concentrations that will provide a range of data commensurate with the most reliable operation of the instrument and the computer. To enhance their understanding of interfacing, students write a comprehensive report that describes the procedures and apparatus they have used, as well as the relationships between what they measure, how they measure, and what they conclude. These reports reveal that the careful attention to detail inherent in the use of computers improves the quality of our students' laboratory work.

NEVADA

ForCP/M

Powerful subset at ANSI-74

Why wait?

All the elegant simplicity

of COBOL la now affordabSe!

r

$QQ

DISKETTE ^^W ^^W MANUAL ^»T ^J

95N

REQUIRES only 16K RAM. Available on 8" CP/M standard single density or 5%" diskettes for North Star, TRS-80 Mod I and Superbraln. Other formats tool Manual alone $24.95. '

<*e> Ellis Computing

^ 600-41st Avenue

San Francisco, CA 94121 U.8.A.

These powerful, easy to use COBOL APPLICATION PACKAGES

are also available:

1. BUDGET PLAN REPORT GENERATOR

Fantastic time saver and planning aid for beginning or established businesses.

2. PERSONAL FINANCIAL REPORTING

Eye-opening Insights of personal spending.

3. LABELS lor mailing lists.

4. PRECOBOL (a preprocessor).

ALL 4 in one BOOK!

73 pages with complete COBOL source code listings and super documentation.

$24

95

WE WELCOME C.O.D.s

^2 L^ftJ

[415)751-1522

In CA add sates tax. CP-M trade mark of Digit*! Research. TRS-80 trade mark of Tandy Corp.

Conclusions

We have just begun to teach interfacing of computers in the laboratory. Yet, we believe that such teaching is valuable and conclude:

• Many students who have not used computers fear them and the specific action required to use them successfully.

• Once they use microcomputers to solve traditional problems in chemistry, students develop confidence and approach interfacing with enthusiasm.

• Because students can write software to analyze data only if they possess understanding and expectations of their intended studies, interfacing microcomputers with instruments encourages them to study their project before they begin work in the laboratory.

• Interfacing encourages students to gather more data and analyze the statistical reliability of their information. Moreover, qualities such as signal-to-noise ratio, rates of measurement, and detection limits, frequently given minimal attention in traditional laboratory work, receive careful attention from students when they interface a microcomputer to a laboratory instrument.

• By interfacing the microcomputer with instruments, students learn the differences between analog and digital information and how to report precision and significant figures with the aid of hardware and software.

• Writing software compels students to select a format for information they will report. Thus, experiments that use interfacing encourage students to consider their reader as they use the computer to prepare charts, tables, or outlined presentations of their data and conclusions.

• Interfacing encourages students to blend the systematic use of a computer with their experimental work. Thus, students use, to their benefit, flowcharts to select and guide laboratory activity, or design software for their projects.

• Interfacing of computers encourages a sense of community among students in the laboratory. We urge them to solve their experimental and software problems independently and this produces a variety of solutions for gathering and interpreting data with the aid of the computer. Students enjoy comparing solutions and merging ideas that improve on the techniques they have used.

Our students have emerged from these projects with more confidence in their ability to solve problems. From interfacing, our faculty has gained a more comprehensive basis for discussing the design of laboratory projects and the significance of results that students report. Interfacing microcomputers in the laboratory has guided our students to more detailed awareness of cause and effect. We are designing other interfacing projects that will extend similar educational benefits to students in other laboratories of this department. ■

References

1. Scientific American, 237 (3), September 1977; The Physics Teacher, 16 (10), October 1978.

2. Gerhold, et al, "Bits, Bytes, Boards, Buses, and Beyond," J. Chem. Ed., 56(3), 701 1979.

3. Fudge, A J and Sykes, K W, Journal of the Chemical Society, 119, January-March 1952.

4. Hershey, A V and Bray, W C, Journal of the American Chemical Society, 58, 1760, 1936.

278 February 1981 © BYTE Publications lnc

Circle 188 on inquiry card.

Why is the 88G Printer the new industry

leader?

QUALITY

The attractive, durable 88G casework is formed from impact-resistant, flameretardant Styron. Microprocessor controlled stepper motors provide precision control over print head and paper positioning. Computer quality tractors position paper for readability and are fully adjustable to accommodate varying paper widths.

MICROPROCESSOR CONTROLLED INTERFACE

The microprocessor array provides the intelligence for a dual RS232 serial and a Centronics® type parallel interface. Both inputs are fully buffered to allow the 88G to receive data and print simultaneously. A IK character buffer is standard with a 2K buffer available as an option.

The short line thruput of the 88G has been increased by incorporation of a Quick Cancel feature that fully utilizes the bidirectional/unidirectional printing capabilities. Built-in diagnostic and self-test capabilities allow the user to easily pinpoint system problems and a Power On confidence test verifies operational status of the printer each time power is applied

VERSATILITY

The 88G prints a full upper and lower case 96 character ASCII set with a crisp, clear 7x7 matrix in 80, 96, or 132 column formats. For text processing and correspondence applications, an 11x7, 80 column serif style matrix can be selected by switch or software command. The dual tractor/pressure-feed paper drive system allows the user to choose either pin-feed, roll, or single sheet papers up to 9.5 inches wide.

Complete forms control allows the 88G to be quickly configured for printing single or multiple-ply invoices, purchase orders, checks, or any type of preprinted form. Optional paper roll holders and single sheet feeders can be quickly attached.

The wide use range of the 88G makes it the perfect companion for business systems, data processing, RO teleprinter and terminal printer applications.

GRAPHICS

A high-resolution, dot-addressable graphics option can be added for applications requiring plotting, printing of screen graphics, drawings, illustrations, etc. Single dot print resolution greatly extends the usefulness of the graphics capability. Selection of one of the four horizontal dot densities available customizes the graphic printout, and alphanumerics can easily be included for titling of graphs and illustrations.

LONG LIFE RIBBON CARTRIDGE

Ribbon difficulties are minimized through use of a continuous loop cartridge with a five million character life. It is easily changed without opening the case, and without any complicated or messy threading operations.

PRICE

Every detail is directed toward providing a heavy-duty, commercial quality printer for only $749.00. No other printer on the market today can provide its quality, features and performance at a comparable price. The 88G is an obvious industry leader.

Centronics is J registered trademark of the Centronics Ddt<i Computer Corp.

Circle 192 on inquiry card.

Micro Peripherals, Inc. 4426 South Century Drive Salt Lake City, Utah 84107 Phone (801) 973-6053

Ask BYTE

Conducted by Steve Ciarcia

Sensing Alarms

Dear Steve,

I am currently designing a home-alarm system. I have been reviewing your BYTE articles from January 1979 thru March 1979. (See "Build a Computer-Controlled Security System for Your Home," Part 1, January 1979 BYTE, page 56; Part 2, February 1979 BYTE, page 162; Part 3, March 1979 BYTE, page 150.) I am hoping that you can clear up a couple of questions I have about your articles.

For a little background, my computer system is based on a Z80 microprocessor, rather than the 8085. I will be using sensors which you described in your article, and that is where my questions arise.

To begin with, I refer to photo 3 (January 1979 BYTE, page 68) and figure 1 (March 1979 BYTE, page 151). Is the LM3911 integrated circuit equivalent to

the sensor in photo 3? Can the sensor in photo 3 be used in the system by adding the comparator in figure 1, but leaving out the temperature trigger-point potentiometer, since the sensor in photo 3 will trip above a certain point? My idea is shown as a schematic diagram in figure 1 below. If a commercial device is suitable, can you recommend one for me to use?

Thank you for your time. Brian P Mulhearn

The sensor shown in January's photo 3 is simply a temperature sensitive switch (shown here as figure 2). It operates like any pushbutton switch. It is either open or closed. When the temperature is below 135° F it will be open, and above that temperature it will be closed. The circuit in figure 2 is a way to test these devices. It consists of an LED (light-emitting diode)

Figure 1

+ 12V WOULD A RESISTOR

A BE NEEDED HERE TO

REPLACE THE POTENTIOMETER?

>5.6K

-5V

A

LM3911

T

10K -vw

-l3>output

m

and a 6 V battery. Just dip the sensor in hot water and the LED should light.

The LM3911 is a linear integrated circuit and not a mechanical switch. It uses the difference in emitter-base voltage of transistors (operating at different current densities) as the basic temperature sensitive element. The output voltage of the LM3911 is directly proportional to temperature in

Figure 3

LM 3911

INSIDE DIAGRAM

6.8V ZENER

degrees Kelvin (10 mV/°K). External resistors can scale this to any desired value through an op amp. Internally, the LM3911 appears as in figure 3. The device itself is the temperature sensor. To measure the temperature of a water pipe, the LM3911 would have to be placed against the pipe. To make it operate like the mechanical sensor, a comparator is added which trig

-Opin 3 +v

T

-\ >PIN 2 FEEDBACK INPUT

•50K

-{3>PIN l OUTPUT

10mV/°K

-f^>PIN 4 -V (GND)

Figure 4

+12V +12V

$ 4

50K TEMP TRIGGER -VVV 1 SET POINT

IC1 LM3911

£

10K

£3>0UTPUT

Figure 5

+ 5V

Figure 2

srt

v

27011 -V\Aj

LED OFF = TEMP< 135°F LED ON = TEMP > 135°F

. 4.7K

T=135"F

ies«

-l3>output

OUTPUT

LOGIC "1" LOGIC "0"

135' 135'

280 February 1981 © BYTE Publications Inc

The PRACTICAL MICROCOMPUTER PROGRAMMING™ books

WHAT DO THE CRITICS SAY?

BYTE: "It was apparently Mr. Welter's goal from the beginning to present the fundamental concepts ol assembly language programming in a completely nonthreatening way. He has accomplished this better than any other author to date.. .Practical Microcomputer Programming is' a very powerful series. It is well written and full of essential techniques for the assembly language programmer."... "The authors know the difference between a novice and a ninny. They never talk down. . . on every page the authors spot and clear up the small ambiguities of technical jargon that can block understanding."

Kilobaud: "A powerful plus for this book is the author's determination to demonstrate why and how to use each instruction, not merely to explain how it works.. .At no point do the authors resort to rehashing material available from the manufacturer... but instead choose a less theoretical, more practical approach."

Leventhal: ".. .large numbers ol documented, well structured examples, and a clear readable style, a logical development of major topics."

Digital Design: "This book is the best and most lucid introduction to Z80 programming that we have seen."

CACHE: "This is an EXCELLENT book. . software and documentation."

.dirt cheap for such great

IF YOU'VE TRIED THE "CHEAPJES" AND AREN'T SATISFIED WITH WHAT YOU GOT, IT'S TIME TO TRY THE REAL THING, THE ACKNOWLEDGED WORLD STANDARD OF TECHNICAL EXCELLENCE IN ASSEMBLY LANGUAGE PROGRAMMING INSTRUCTION—THE PRACTICAL MICROCOMPUTER PROGRAMMING BOOKS.

■ FOR THE 6502 PRACTICAL MICROCOMPUTER PROG RAMMING: THE 6502 by W. J. Welter $32.95

20 chapters, 6 appendices, 475 page Smythe sewn hardcover covering all fundamental assembly language techniques lor the 6502 processor. The text explanation is re-enforced with 118 verified, real world programming examples that run on real computers. An extended 6502 language, supported by a new editor/assembler which comes with the book, circumvents many of the problems which have made the 6502 so difficult to program in the past. In addition to the fundamental technique chapters, there are special chapters covering simple graphics, elementary cryptography and random number generation and use. The source texts of both the editor/assembler and a powerful new debugging monitor lor the Apple II and Apple // + included in appendices. The object code for this software is supplied FREE to book purchasers on Apple cassette or lor $7.50 on disk when the licensing agreement from the book is returned to the publisher. The editor/assembler is also available on paper tape for users of other 6502 based systems.

■ FOR THE Z80 ■

PRACTICAL MICROCOMPUTER PROGRAMMING: THEZ80 by W.J. Welter $32.95

18 chapters, 4 appendices, 481 page Smythe sewn hardcover which details assembly language technique as applied to the 180 processor. The Z80 is treated as an 8080 superset in an 8080 extension language, which means that you don't have to discard your hard won 8080 knowledge to program the ZBO. In addition to the fundamental chapters there are chapters on graphic output and full four function decimal arithmetic. The text explanation is re-enforced with 104 tested, verified programming examples. A powerful editor/assembler and debugging monitor, in source form, are provided to support the language used in the book. This software will run on any Z80 based computer with 10K RAM beginning at 0. Object code lor both editor/assembler and debugging monitor is sent to book purchasers FREE on paper tape or, in modified form, on TRS-80 Level II cassette when the coupon from the book is returned to the publisher.

■ FOR THE 8080 ■

PRACTICAL MICROCOMPUTER PROGRAMMING: THE INTEL 8080 by Weller, Shatzel and Nice $23.95

18 chapters, 3 appendices, 318 page Smythe sewn hardcover which applies fundamental assembly language technique to this most popular of processors. The text is supported by 84 separate programming examples. The book includes a special section on the handling ol complex peripheral devices and exotic typefaces. Appendices give the source for an 8080 resident debugging monitor and a minicomputer cross assembler lor the 8080. Also availablefnot shown above) are a workbook for use with this text ($935) and AN EDITOR/ASSEMBLER SYSTEM FOR 8080/8085 BASED COMPUTERS ($15.95) which supports the language used in the text. These three books together make a complete teaching package lor the 8080.

■ FOR THE 6800

PRACTICAL MICROCOMPUTER PROGRAMMING: THE M6800 by W.J. Weller $23.95

76 chapters, 2 appendices, 299 page Smythe sewn hardcover text which details the application ol fundamental assembly language technique to the 6800. 104 separate programming examples re-enforce the text explanation. Contains in addition special chapters on low precision trigonometry and random number generation and use. A resident debugging monitor lor 6800 systems is included in an appendix.

NO GAMES, NO NONSENSE, NO REPRODUCTIONS OR REHASHES OF MANUFACTURER'S DATA SHEETS, JUST TESTED, ACCURATE, RELEVANT PROGRAMMING INFORMATION BACKED UP BY REAL EXAMPLES THAT RUN ON REAL COMPUTERS—THE PRACTICAL MICROCOMPUTER PROGRAMMING BOOKS. THERE IS NOTHING ELSE AS GOOD ANYWHERE, AT ANY PRICE.

Mail to: Northern Technology Books, Box 62, Evanston, IL 60204

D Practical Microcomputer Programming: The 6502

□ Practical Microcomputer Programming: The Z80

□ Practical Microcomputer Programming: The Intel 8080

□ Practical Microcomputer Programming: The M6800

D Workbook for Practical Microcomputer Programming: The Intel 8080 D An Editor/Assembler System for 8080/8085 Based Computers

D Check enclosed (U.S. funds only)

Name

Street

City

D Money order enclosed

. State

-Zip

$32.95 $32.95 $23.95 $23.95 $ 9.95 $15.95

Illinois residents add 5% sales tax

Ask BYTE

gers when a preset level is reached (see figure 4). The 50 k-ohm potentiometer is set for some temperature of interest. When the output of ICl exceeds the setting, the output state of IC2 changes. The advantage of this circuit over the mechanical sensor is that any temperature may be set.

It appears that you want a sensor that signifies a temperature greater than 135° F and is compatible with the computer input. Using the mechanical sensor, this can be accomplished with the circuit in figure 5. A 7414 Schmitt-trigger inverter produces a clear output level once contact bounce has ceased. If you prefer, CMOS (complementary metal-oxide semiconductor) devices can be used instead to reduce power requirements. ...Steve

Probing for Probes

Dear Steve,

This is a nontechnical request, but I sure hope you can help me.

I have been trying for two months to locate an outlet for the type of probes shown in photo 5 of your article "Mind Over Matter: Add Biofeedback to Your Computer," (June 1979 BYTE, page 56). After a letter, three Telex messages, and three telephone calls to American Optical (both east coast and west coast), I finally received a reply from Cambridge Instruments, formerly American Optical, Medical Division, saying, "We don't make the probes, and we don't know anyone who does."

I wear a transcutaneous electronic nerve stimulator over a shoulder injury. The flat carbonized-rubber probes, held on with separate adhesive, sometimes lift free of skin contact when I am active. The normal 40 V 23 ^s pulse (loaded voltage) goes up to about 400 V open line voltage. When it again contacts the skin, it arcs and makes a

sore spot.

Your probe, with the predrilled sponge center, looks as if it would work much better—if I could only locate it. If you give me the address of the medical supply house where you obtained yours, I will contact them directly. I used biofeedback for several months at the UCLA Pain Control Unit, and I intend to build the unit you describe in your article, using a scope as an output, and possibly interface it to a computer later. Bob Vinson

The two kinds of silver/ silver-chloride electrodes I tried were P/N 5113 from American Optical and P/N 14245B from HewlettPackard. The probes themselves were nothing more than fancy clips at the end of 3 feet of shielded cable. When using three probes as shown in the article, the three shields are connected together and attached to the guard input of the isolation amplifier.

I hope this information helps Steve

Remote Data Entry

Dear Steve,

I have been trying to find a way of interfacing inexpensive terminals (calculator-pad type) to the TRS-80. I have also been trying to locate a method for doing this with as many as thirtytwo terminals. The system would be used as a feedback device for working with small to classroom-size groups. Can you give me any leads to manufacturers of hardware, designers of such systems, and persons who have expertise in such matters? Brother Eugene Meyerpeter, SM

In the September 1980 BYTE, my "Circuit Cellar" article was entitled "Build a Low-Cost, Remote DataEntry Terminal" (see page 26). And it is exactly what you need. To build this terminal, it takes essentially a calculator pad, which you

make into a serial terminal using only two integrated circuits. All communication is at 1200 bps (bits per second), full duplex.

To use it in your environment, you would build thirty-two of them and attach them to the TRS-80 through a serial port (such as the Radio Shack TRS-232 board or a COMM-80). To communicate with a single student, you would need a 32-position switch to allow you to select the individual line from that student's terminal. All outputs to the remote terminals can be tied together when you want the same message sent to all units simultaneously.

I have presented the design, but I don't know anyone producing it currently. Perhaps you could find an enterprising person who would custom-build thirtytwo of them for you from my schematic...Steve

Voltage Fluctuations

Dear Steve,

I have a Radio Shack TRS-80 Model I. Occasionally the machine acts strangely, either by "locking-up" so that the reset button must be used to start it again, or by randomly accessing the disk. When I first got the disks, the problem with the random accesses was quite frequent. I have since purchased Radio Shack's power-line filter and it seems to have almost eliminated the problem.

I suspect that the difficulty is caused by fluctuations in the voltage in my office. I have noticed interference on the video display when running the printer and when the air-conditioning unit starts. However, neither of these seems to cause the problem, at least, not consistently.

The landlord says that the power service into the building is 600 amps. Also, certain offices having unusual power requirements have their own circuits

within the building (not, however, separate service entirely). He also has some sort of transformer that he says should eliminate fluctuations caused by the air conditioners.

My questions are:

• Is the TRS-80 sensitive to power fluctuations?

• If so, how can I monitor the circuits in my office to determine whether the computer's requirements are being met?

• If the circuits aren't adequate, is there any way to shield the computer from the fluctuations?

• If power fluctuations aren't to blame, what might be?

I have no knowledge of electronics, so I would be interested in either buying or renting (or borrowing) whatever I might need to solve the problem, rather than building something. Guerri F Stevens

Intermittent operation and bizarre behavior are by no means limited to the TRS-80. It can be a problem with any computer installed and operating under what might be termed marginal conditions. There are quite a few TRSSOs, so, if just 1 % have problems, approximately 3000 people would have complaints.

The first order of business is to determine the source of the problem. Three possibilities immediately come to mind:

• bus cabling between peripherals

• power fluctuations

• power-line transients and induced noise

Make sure you keep the interconnecting cables between peripherals away from power lines and as short as possible. Do not leave equipment attached directly to the computer that is not powered or properly terminated. Keep the bus cabling and disk cables away from the left side of the

282 February 19S1 © BYTE Publications Inc

Year End Surplus Inventory

New Data Terminals

Mfgs. List Texas Instruments price

Model KSR 733 $1050.00 ... $1920.00

with modem $1250.00 ... $2335.00

Teletype

Model 43(4320 AAE $850.00 ... $1355.00

Immediate Delivery

703-893-2250 Ext. 270

Milton Foster

7798 Old Springhouse Road

McLean, Va. 22102

Get Paid

for

Your Software!

Established publisher looking for new and interesting business and communication oriented applications for Apple computers. No games.

Send Info to:

M.G. Hill

54 Ridge Avenue

Newton Center, MA 02159

8035 SYSTEMS

A compact modular set of PC Boards for implementing test instruments, measurement and control systems, badge readers, data communications, data entry, games or home security systems.

KIT A&T

S99 S125

CPU Board. 8035. 2 71 6

1 K RAM. 40 I/O Lines

SIO Board. 3 8251A. RS 232

Dr/Rec. 6 LEDs

PIO Board. 2 8255 PIOs. Line Drivers

2 or 3 Slol Mother Boards . .. Power Supply. 5V, 12VS-12V Diagnostic EPROM andListing

Bare Boards. Schematics and Parts Lists, each

99

99 ~55

125

125

50 65 40

. . S19.95

Boards are 4" by 7". 8$pins. 156 centers edge connector. Development Tools available on CPM.

Make check payable to:

SKP Electronics

221 1 Caper Tree Or .Tustin. CA 92680

(714)832-1732 California residents add 6°o sales tax Please add S3 00 for shipping and handling

Circle 193 on Inquiry card.

Circle 35 on Inquiry card.

A NEW WIRELESS AC REMOTE CONTROL INTERFACE for the Sears and SSR X-lo home control system. Use your present TRS-80 Level II, Apple II or S100 computer to provide complete home security through control of lights, appliances and motors with a few simple BASIC commands.

As featured in: "COMPUTERIZE A HOME" BYTE. January 1980

Busy Box - Assembled & tested For TRS80 ..$109.95 ForSlOO .... 119.95 For Apple II. ..114.95

Realtime control software - TRS-60 19.95 Toordercall (516) 374-6793 or write: The MicroMint Inc

917 Midway,

Woodmere. NY 11598

DEALER INQUIRIES INVITED

BUSY BOX

SPELLING

eliminated with

SPELLGUARD™

Proofreads 100 pp. per minute with Wordstar or Magicwand.

Spellguard $295

Wordstar $325

w/Spellguard $595

Magicwand $275

w/Spellguard $520

TDA 1635 Schot)l st

I rMlvloraga, CA 94557

(415) 376-3753

OAE's PP-Series EPROM Programmers plug directly into any vacant EPROM socket and allow you to transfer data directly from RAM to E PRO Ms. No additional power supplies are required. All timing & control sequences are handled by the programmer. Each unit includes internal DC to DC switching regulator, ZIF and 4 ft. ribbon cable terminated with a 24 pin plug. Programmers are available for all EPROMs from 2708's thru 2532's.

Oliver Advanced Engineering, Inc.

676 W. Wilson Ave., Glendale, CA 91203

(213) 240-0B00 or Telex 194773.

PP SERIES PROGRAMMERS

Circle 326 on inquiry card.

A ATARI*

COMPLETE LINE OF ATARI COMPUTER PRODUCTS 20% OFF

Atari BOO with 16K $799

Alari 810 Disk Drive $525

Alari 815 Dual Disk Drive $1200

NOW IN STOCKI

RAMCRAM 32K RAM MODULES $256

VISICALC $170

WE ARE ATARI EXPERTS IN BOTH HARDWARE AND SOFTWARE

EXCLUSIVE BIT BUCKET SOFTWARE FOR ATARI: Utilities Disk with Disassembler, Character Generator, Basic Renumberer,

Cruncher Utility (requires 24K) $45

Brain Games Disk with MastercorJe. Hex,

Memory, Mr. Simon $30

Action Games Disk $30

•jfial ^E ^" Bucket

,<rvyr 168 Noun Beacon Sireet

.'.,. . PO Box 365

ryl Newlon Highlands. M<\ 02161

°t_J Phono 1617) 783 3144

LETTER QUALITY

DAISY WHEEL PRINTER $2,195.00

* Based on latest version of electronic typewriter by Olivetti, Ltd.

* Use offline as typewriter

* RS232C Interface Standard

* Over 200 words per minute

* 10, 12 ck 15 C.P.I.

* International Type Fonts

* Available Immediately Money order or C.O.D. to:

Vertical Data Systems, Inc

1215 Meyerside Dr., Unit 2A

Mississauga, Ontario, Canada

L5T 1H3

(416)671-1752

Circle 327 on inquiry card.

! (SURPLUS NEW! !

IIMTEL BOARDS

ASKING DIST. COST OR LESS; WILL ACCEPT BEST OFFER. LIST ASKING

SBC 80/20 COMPUTER $925 $650

SBC 534 QUAD SERIAL IO _

790 550

SBC 711 ANALOG INPUT

1400 600

SBC 604 4 SLOT CAGE

235 170

SBC 614 4 SLOT EXPANDER

235 170

BLC416 NATIONAL 16K EPROM

330 250

QUANTITIES LIMITED! CALL KIRK OR BOB AT

[9183 664-2255.

Circle 328 on inquiry card.

Circle 329 on inquiry card.

Ask BYTE

video display (where it can pick up noise from the highvoltage flyback transformer).

Power fluctuations can indeed cause marginal operation. In my mind, however, there are two separate problems: fluctuations and transients. Fluctuations are slow (greater than 5 ms) voltage changes involving a 10 or 20% variation in line voltage. As long as the line voltage does not dip below 105 V AC, you should be all right. Have you ever noticed your room lights dim when you plug in a toaster or an air conditioner? Well, that dimming of the lights is a typical case of power-line fluctuation. A drop of only a few volts will visibly dim a lamp. Fixing this problem is easy, but it is expensive.

Transients, on the other hand, are fast (1 fis to 5 fas) changes in line voltage. Generally these are caused by the inductive kickback of motors and equipment. Usually, the more sophisticated

measures employed to limit general line noise (a powerline filter) will eliminate this problem as well. If you have particularly strong narrowband noise, then a special low-pass filter may have to be used. For example, if the reason your computer malfunctions is the 200 W radio transmitter from the business next door, then a 30 MHz filter might be required.

The fact that you have no knowledge of electronics limits the diagnostic tests that you could use to determine the problem. If you can find a nearby Radio Shack store (or, perhaps, a friendly technician) where you can obtain a VOM (volt-ohm-meter), set it on the 200 V AC range and put the probes in the wall socket next to the computer. The "safe range" is between 110 and 120 V AC. If, however, you notice the indicator taking a dive every now and then, you have a lineregulation problem. This is

bra™ ffimnGDn

P K^^^J^C^

P

b [

b

Q

^Vt^S^^^^ Pr*^

0

9

**r ^^^^

9

9

^^^^^

9

n j

OT PACKAGE SI600O

n

1 ^ L2D 4, L3P PACKAGES S36O0O IfS | MAURO PROAC MP 250 PLOTTER 563500

LI

I 3 «"" L3D package 5JS5CO

U w.lh L2D 1 L3P packages S95000

n

MAURO PLOTTER - Uses II' wide paper ol any length sucn as B - bond or 17" graph paper Plotting

resolution .s 200 steps per inch w.ih 005 Hacking error at plotting speeds ol up to 2' •" per second Uses

standard liber l.ppenslhalcanbeobla.nedalanySlal.onaivSloie ReOunesonl v5 b.tsolaparallelou.Piil port

1 1 Vector driver software m source is supplied with mc plotter lor 6080 280 6502 & 6800 micro processors

□| APPLE TRS 80 and RS 232 interface cards are available as options

LEAPAC SOFTWARE - Complete Iwodimensional and perspective plomng soil ware packages are available

p

L SI become obsoleled as vou upgrade your plotting equipment The sollwaru is supplied as 8080 Z80 relative

p

UL1 linking 1ibraneslL80lloi MICROSOFT compalable oroducis FORTRAN 80 COBOL 80 COMPILER BASIC a.rd

f pi] MACRO 80 on 8- CP M, or 5'." NQHTHSTAR TRS BO or HEATH 89 comrjaiable diskeites

l_yj L2D PACKAGE - Two dimensional plot package trial contains over 25 emr.esihat allowyouioctipor

|DJ

■ v window your drawings annolate vourdraw.ngs and draw ell.Dlical curves Contains CalCompComp

P alable calls such as PLOTS PLOT WHERE FACTOR etc !—-' L3P PACKAGE - Perspective or Ihree dimensional clot package that contains over 70 enlr.es that

Q

nj] allow vou to plot perspective hgures such as the self portrait above Routines for STEREO GENERA | TION ZOOMING FLY BYS. and ANIMATION are built into the package lor minimal programming

H

I 1 pages describing the use of Ihe above packages Cedil back on purchase oi packages

□

] Besides Ihe Mauro Plotter interlace, optional drivers are available lo. CalCompand Houston Instrument Drum S r plolteis Houston Instrument HIPLOT CMP 3 4(17 plollers. and diasv wheel or spindle printers such as

9

U DIABLO 1620 r. 1640 OUME SPRINT 5 and NEC 5510 & 5520

1 Ej LEAPAC SERVICES (916) 381-1717

2 ) 82*5 MEDITERRANEAN WAY SACHAMENTO CALIFORNIA 95826

L5

' CP- M is a regislered trade markol Digital HesearCh. Inc HIPLOT & DMP are trade marks ol Houston Instrument

TRS 80 is a trade mark ol Tandy Coiporal.on

280 is a trade mark ol Zilog. Inc

only a rudimentary check, because the meter has slow response. Checking for line noise and transients requires an oscilloscope (to see the fast pulses).

If you find you need better power-line regulation, you will have to resort to a constant-voltage transformer from the power company (or it may be installed privately). Two companies to contact for further information are: Sola Electric, 1717G Busse Rd, Elk Grove Village IL 60007, (312) 439-2800, and California Instruments, 5150G Convoy St, San Diego CA 92111, (714) 279-8620. Finally, if all else fails, you could encase the entire computer in copper screening and run it from a battery. See my article on "Electromagnetic Interference" in last month's BYTE....Steve

Should I, or Should I Not?

Dear Steve,

I would like your opinion on the purchase of a computer through mail order.

Although a Radio Shack dealer is only a 5-minute walk from my house, the discounts offered by out-ofstate dealers on the TRS-80 make a mail-order purchase very tempting. Can you give me your thoughts before I send a $700 check to someone sight unseen? David Kupferman

The only sure way to tell the winners from the losers in the mail-order business is with time. No company that is crooked will be in business very long. Remember that there have been those occasions where many people were swindled in a short period of time, as happened with World Power Systems. For the most part, the good prevail.

I suggest that you review past issues of BYTE and look for advertisers who have been there for a long time and have steadily increased their product line. This will give you some in

dication of stability and market responsibility.

While it is always good to go to a store and see the item that you are purchasing, much can be gained from mail-order buying. In general, mail-order outlets offer discounts well below the store prices, and, when you order outside of your home state, you usually pay no sales tax; however, you often pay shipping costs.

If you are still concerned, find someplace that takes cash-on-delivery orders and pay for your computer when it arrives on your doorstep Steve

Modem

Dear Steve,

Thanks for the article on modems. (See "A Build-ItYourself Modem for Under $50," August 1980 BYTE page 22.) It got me thinking about something.

I am an ACM (Association for Computing Machinery) member at OSU (Ohio State University). I am lucky enough to be able to have an open account on computers like the DEC PDP-10, IBM 370, and PDP-11. To log onto the system, you call a telephone number, and I would like to use the modem you described to do this from my dorm room. (I have to walk about fifteen blocks to get to the computer center, and, boy, is it cold in the winter.)

How can I build a cheap key board/modem/television set terminal? I can wirewrap and understand schematic diagrams. I know a bit about computers but not a lot. Marc Taylor

At first I was going to point out that there have been numerous articles in previous issues of BYTE on the design and construction of a video terminal. There are also some kits offered for less than $200 in the advertisements at the back of every issue. At least that's what I was going to say.

284 February 1981 © BYTE Publications Inc

Circle 194 on Inquiry card.

Can You Tell Which Tax Practitioner Uses Aardvark Software?

AardvarkSoftware, specializing in tax-related applications, helps you save time and energy while your clients' benefit from the most comprehensive tax programs available. Our programs are designed by CPAs with over 17 years of "Big Eight" taxexperience. These programs meet or exceed the requirements of most professional tax practitioners.

Our programs run on a variety of microcomputers, including Apple, TRS-80 and Commodore.

Tax Preparation

"Tax Prep" allows you to easily calculate your clients' Federal Form 1040, all lettered schedulesexceptR & RP and the most frequently used numbered forms. Selected state forms are also available. Since this system is user-oriented even a novice can process returns immediately.

Price $495

Tax Planning

"Tax Plan" is designed to eliminate hours of work and human error in evaluating various tax alternatives for your clients. It allows you to enter a variety of income and expense items and to determine the tax effects attributable to changes in one or more items.

Introductory Price $395

Depreciation

Quickly computes current year bonus and tax preference depreciation, investment tax credit, and investment credit recapture. At your option the program will automatically switch from accelerated to straight line depreciation, when beneficial. Printed output is available in tax return and/or worksheet format.

Introductory Price $150

Estate Tax Planning

"Estate Plan" permits a comparative analysis of the Estate & Gift Tax effects of different levels of wealth and/or lifetime gift strategies. The user hasthe ability to input a variety of taxable estate assets and valuations.

Introductory Price $595

Aardvark Software1" programs are fast, efficient and easy to use.

Of course, if you enjoy working nights, weekends, holidays,...

For more information, please write orcall us.

AARDVARK SOFTWARE IMC

The Microcomputer People for Professionals

783 NORTH WATER STREET M ILWAUKEE. WISCONSIN 53202 414/289-9988

Circle 120 on inquiry card.

BYTE February 1981

285

Ask BYTE

However, I have changed my mind in favor of practical reality.

Microcomputers and terminals configured from them are becoming cheaper all the time. It isn't quite like the 6-transistor radio or the calculator—yet. But, you may find that the cost of building a terminal is greater than what it costs to buy one. This is especially true if you purchase used equipment.

Also, the new Radio Shack Videotex combination terminal and modem for $399 is worth investigating. It sounds exactly like what you need—at a reasonable price.

As soon as I can get a chance, I'm going to attempt to make a terminal using the Sinclair ZX80 computer. How does a $300 smart terminal sound?... Steve

Shedding Some Light

Dear Steve,

My name is Chris

Richard, and I'm 13 years old. I am doing a science project called "Talking on a Beam of Light." I saw your article in the May 1979 BYTE (see "Communicate on a Light Beam," page 32), and I was wondering if you could tell me where I can buy some optical fibers. Could you also send me a list of reading material on optical communications; I am especially interested in getting several plans for optical transmitters and receivers.

I really enjoyed your article, and I learned a lot from it. Thank you for any help you can give me. Chris Richard

The best sources of information on optical fibers are the manufacturers themselves. Many of them publish application notes which are usually free for the asking. Three of the largest suppliers are: Amp

Inc. 449G Eisenhower Blvd, Harrisburg PA 17105; Corning Glass, Electronic Products Division, Department G, Houghton PkA2, Corning NY 14830; and Galileo Electro Optics, Department G, Galileo Pk, Sturbridge MA 01918.

Another source of circuits comes from optoelectronics manufacturers application notes. These are companies with familiar names like Texas Instruments, General Instrument, General Electric, and HewlettPackard. Any good library should have an electronics

manufacturers product directory. Ask the librarian if he or she has the Gold Book or EEM Directory.

As far as getting optical fiber materials, unless you want a few thousand feet of cable, I suggest you write for a catalog from: Edmund Scientific Company, Department G, E Gloucester Pike, Barrington N] 08007.

I think you have chosen a good subject. I wish you luck. When you write to the optics companies, tell them it is for a science fair project. You may find them to be very helpful....SteveM

In "Ask BYTE," Steve Garcia answers questions on any area of microcomputing. The most representative questions received each month will be answered and published. Do you have a nagging problem? Send your inquiry to:

Ask BYTE

do Steve Garcia

POB 582

Glastonbury CT 06033 If you are a subscriber to The Source, send your questions by electronic mail or chat with Steve (TCE317) directly. Due to the high volume of inquiries, personal replies will be given as time permits. Please enclose a self-addressed, stamped envelope, and be sure to include "Ask BYTE" in the address.

THE CONFIGURABLE BUSINESS SYSTEM™ helps you move full speed ahead when you use a computer. Developed by programming experts especially for the microprocessor environment, CBS provides all the detailed documentation you need to

more efficiently — and more effectively.

It gives you a method instead of madness. And a program instead of problems.

Disks and manual, $395. Manual only, $40.

ALL SYSTEMS GO

create customized systems without using a computer language.

From your initial data input to your file design, CBS helps you use your computer

CBS Disks can fit any 8080 or Z80 computer with a CP/M." Your DMA representative can tell you about DMA»DOS, our CP/M compatible operating system, and ASCOM, an Asynchronous Communication Control Program.

DMA • WE SPEAK YOUR LANGUAGE

DYNAMIC MICROPROCESSOR ASSOCIATES /545 Fifth Avenue/New York, New York 10017/(212) 953-1721/MasterCharge and VISA accepted. We ship prepaid and COD orders. Shipping and handling charges extra. CP/M" is a Trademark of Digital Research Corp.

286 February 1981 © BYTE Publications Inc

Circle 195 on Inquiry card.

Our State of the Art thinking gave you S ARGON.

But chess isn't all we think about!

SARGON II (Spracklen) The Champ of champs "..an excellent program which will provide a (rue challenge for many players - Save your money and buy SARGON II... " '80 Software Critique. 03403. TRS 80 Level II: 03404. Apple It: 03410. OSI CIP: 03440. OSI C4P: 03401. PET: each tape S29.95. 03408. TRS 80 Level II Disk: 03409. Apple I! Disk: 03414. OSI CIP Disk: 03444. OSI C4P Disk: 03484. C8P Disk: each $34.95

BLACKJACK MASTER: A Simulator Tutor Game (Wazaney) A serious game that performs complex simulations and evaluations of playing and betting strategies. 05303. TRS 80 Level 11 tape. $24.95:05308. TRS80Disk Versitn. $2995

REVERSAL (Spracklenl

Winner of the software division of the First Inter

national Man Machine OTHELLO'* Tournament.

this version of the 200 year old game Reversi .features

27 levels of play and high resolution color graphics

07004. APPLE II tape. $29 95:07009. APPLEII Disk.

$34.95

APPLESOFT UTILITY PROGRAMS (Gilder) Increase your BASIC programming speed and flexi bility. Contains 9 useful subroutines: 1. REM Wrilei 2. PRINT Writer 3. POKE Writer 4. Hexadecimal Decimal Converter 5. Line Counter 6. Renumber 7. Append 8 Byte Counter 9. Slow Lisl Stop List 03504. Apple II tape. $29.95

FLASH & CRASH SOUND EFFECTS

(American Micro Products)

A collection of 18 subroutines that can be incorpo

rated into your own programs to produce sound

effects with the American Micro Products music

board. Included are: Train. Explosion. Phaser.

Chimes. Sirens. Jet and 12 others.

08709. APPLE II Disk. $39.95

6502 DISASSEMBLER (Stamm) Produce assembly language source files with labeled subroutines and references from programs already in memory It is compatible with Hayden's ASSEM Bl.Y LANGUAGE DEVELOPMENT SYSTEM. 08609. APPLE // Disk. S34.95

PSEUDODISK(Neuschatz)

This money saving program simulates a disk memory system for Integer BASIC programs. It allows multi pie programs in memory al the same time which can be run from a catalog 04804. APPLEII tape. $24.95

LINE & VARIABLE CROSS REFERENCE GENERATOR (Johnson) Provides a cross refer ence of line numbers and variable names. 07301. PET tape. $16.95

DISK CATALOGER (LeBar) Automatically maintains a cross reference listing of all your programs, their location by disk number, their function and use. Catalogs, lists and sorts programs. 05203, TRS 80 Level II taoe. $16.95: 05208. TRS80 LevelIIDisk. $2195

APPLE'" ASSEMBLY LANGUAGE DEVELOPMENT SYSTEM: An Assembler Edilor

Formatter (Lutus) Write and modify your machine language programs quickly and easily. 04609. Apple II Disk Version. S39.95

SUPER APPLE'" BASIC (Lutus) A structured BASIC that compiles into an optimized Applesoft or Integer BASIC program 05409. Apple II Disk. $39.95

MAILING LIST (Tru Data Software) Lists addresses, prints labels, allows for alterations and deletions, and has the capacity to make duplicate data file disks. Can only be used with version 1.5. 05713. Heath tape. $49 95

■ ORDERING INFORMATION

Hayden J

•m Send me the software checked helow A check or money order is enclosed 1 undersland thai Haydfn pays shipping

Book Company, Inc. ■

■ and handling costs and ih

at 1 can return .my disk or tape

within 5

0 Essex Street

fl 10 days il il is defective or

1 am dissatisfied with il for am

m reason Residenls ol NJ and CA musl add sales lax (Jl

er

good in US only

■ □ 00100

□ 02404 □ 03401

□ 03414

O 04503

□ 05103 □ 07009 ■

■ □ 01401

□ 02501 D 03403

D 03440

D 04504

D 05108 D 07301 ■

■ □ 01403

□ 02503 □ 03404

□ 03444

□ 04513

□ 05203 □ 07809 ■

■ □ 01404

□ 02601 □ 03408

□ 034H4

□ 04609

□ 05208 □ 08609 ■

■ O 01407

D 02701 □ 03409

□ 03504

□ 04804

□ 05.308 □ 08709 ■

■ □ 01413

□ 03304 D 03410

□ 04501

□ 04909

□ 1)5409 □ 5681 8 ■

_ Name of individual ordering musl be filled in

B2 81 ■

FINPLAN: A Financial Planning Program for Small Business {Montgomery) Allows you to enter data from a balance sheet into the program, lomake assumptions about future growth of business, and to have the computer project results for up to a fiveyear period based on those assumptions- And if you change any data, the program revises all result ing data automatically. The disk version can only be used with TRSDOS Version 2 3 05103, TRS-80 Level II tape, S69.95; 05/08. TRS 80 Level II Disk Version. $74.95

DATA MANAGER: A Data Base Management

System and Mailing List (Lutus) Store information on a floppy disk, and retrieve it quickly and easily by specific names, or by category. 04909. Apple II Disk Version, $49.95

MCAP: A Microcomputer Circuit Analysis Program (Savon) Performs a linear voltage, impedance, or transfer impedance analysis of an electronic circuit 04501. PET:04503.TRS-80Level II: 04504. Apple II; each lape $24 95: 045J3. HeathkitZemth Disk. $29.95

MICROCOMPUTER AIDED DESIGN OF ACTIVE FILTERS (Gilder) Eight programs that simplify the design of active filters and will calculate the component values needed for various bandpass, low pass, and notch-type filters. 01401. PET: 01403. TRS-80 Level II; 01404. Apple II; 01407. Heath: each tape $16.95: 01413. Heathkit Zenith Disk Version. $21.95

DISK CERTIFIER AND COPIER (Jacc Inc ) A handy utility program that certifies theacceptability of blank diskettes and rejects those with flaws. It also includes a fast machine language disk copying program that will work on single and dual drive systems. 07809. APPLE II Disk. $19.95

SONGS IN THE KEY OF APPLE (Lopatin) Allows you to see and hear your favorite tunes, preprogrammed tunes or music you create (up to 200 notes, including rests, per musical piece). 03304, Apple il tape. $10 95

HOW TO BUILD A COMPUTER-CONTROLLED ROBOT (Loofbourrow) Contains 5

control programs that consist of: Joystick Control Program; Self-Direction Program; Impact Sensor Control Routine; and more. 00100. KIM-1 tape. $14.95 Should be used with text HOW TO BUILD A COMPUTER-CONTROLLED ROBOT, 5681 8. S9.75

Applets a trademark ol Apple Computet Con-.panv. ''K . and is ti()f affiliated with Harden Book Company. Im

Call Toll Free

24 hours a day,

(1 800-821 -3777, ext. 302)* TO CHARGE YOUR ORDER TO Master Card or Visa. Minimum order is $10.00; customer pays postage and handling. From Missouri call (1 -800 892 7655, ext. 302)

Hayden

50 Essex Street, Rochelle Park, IS J 07662 Book Company, ItlC.

Circle 196 on inquiry card.

BYTE February 1981 287

System Notes

Forcing the Z80 Starting Address

Randy Soderstrom, 1201 W Valencia Apt 224, Fullerton CA 92633

Late in the design phase of my homebrew Z80 microprocessor-based system I realized there would be a problem in bringing the system up. My monitor program was in ROM (read-only memory) and was written to begin at hexadecimal page F0, character 00. My programmable memory began at page 00, character 00, and to further

: IC3

; 74126

7102

Z80 )DATA

BUS

OD7"

OD6

C>D5

Od"

0>D3

0°2

r>Di

O>D0

Q>Z80

RESET

7432

RD O

FROM Z80

lirTN—T^MEMORY

noi J |—'decoding

~l ' CIRCUIT

Figure 1: This circuit will force a Z80 microprocessor to begin execution at hexadecimal page F0, character 00, instead of page 00, character 00. The circuit can be easily modified to begin execution at other addresses.

complicate matters, my system had no front panel.

I faced a number of problems in order to get the processor to begin execution at page F0. When the Z80 reset line was enabled, it zeroed the program counter, causing execution to begin at location 00. Since the interrupt mode was unpredictable on power up, it was no help either.

After some thought, I came up with the circuit shown in figure 1. When the Z80 reset line goes low, the circuit prevents the memory from being enabled. Instead, machine code is generated for a jump to the start of the program monitor.

When the reset switch is pushed, flip-flop ICl (integrated circuit 1) is set. This makes the output of OR gate IC2 high, no matter what happens with the processor RD line. Any memory-read operations are inhibited and the IC3 buffers are activated.

While all of this is happening, the Z80 is clearing the program counter and will begin execution on page zero at location 00. However, when the Z80 pulses the RD line low, the OR gate (IC2) blocks it, and no memory data is placed on the bus.

The IC4 NOR gates decode the address, which in this case is 00, and place hexadecimal C3 on the data bus. Since this is the machine code for a jump instruction, it is executed as such.

Next, the processor expects to find the low bits of the branch address. Address 01 is decoded to address 00 and is placed on the data bus. It will be used as the eight loworder bits of the branch address.

Finally, the Z80 places 02 on its address bus and expects the eight high-order bits of the branch address on the data bus. Gates IC4 place hexadecimal F0 on the system data bus. After this byte is read, the Z80 executes the entire instruction and jumps to page F0, character 00.

Because of the jump, address bit A15 goes from low to high, clocking a zero into the flip-flop. This change disables the buffers and restores the system to its normal state.

The Z80's refresh cycle does not interfere with the circuit. The refresh register operates only on A0 through A6.

If you require a more complex initialization, this same concept can be used with a ROM (read-only memory) placed on the bus rather than gates. Done in this manner, the memory space becomes free for other uses after initialization.!

288 February 1981 © BYTE Publications Inc

Software Received

The following is a list of software packages that have been received by BYTE Publications during the past month. The list is correct to the best of our knowledge, but it is not meant to be a full description of the product or the forms in which the product is available. In particular, some packages may be sold for several machines or in both cassette and floppy-disk format; the product listed here is the version received by BYTE Publications.

This is an all-inclusive list that makes no comment on the quality or usefulness of the software listed. We regret that we cannot review every software package we receive. Instead, this list is meant to be a monthly acknowledgment of these packages and the companies that sent them. Companies sending software packages should be sure to include the list price of the packages and (where appropriate) the alternate forms in which they are available.

Apex, disk operating system for the Apple II. Floppy disk, $99. Apparat Inc, 4401 S Tamarac Pky, Denver CO 80237.

Apple Assembly-Language Development System, a 6502 assembler/editor for the Apple II. Floppy disk, $39.95. Hayden Book Company Inc, 50 Essex St, Rochelle Park N] 07662.

Asteroid, graphics game for the Apple II. Floppy disk, $20. Adventure International, POB 3435, Longwood FL 32750.

Communications Software for the RS-232C, utility program for the transmission of data over telephone wires. Cassette, $29.95. Radio Shack, 1 Tandy Ctr, Fort Worth TX 76102.

Concentration, graphics game with sound for the TRS-80. Cassette, $9.95. Adventure International (see above).

Data Manager, data base system for the Apple II. Floppy disk, $49.95. Hayden Book Company Inc (see above).

Dogfight, graphics game for the Apple II. Floppy disk, $29.95. Micro Lab, 811 Stonegate Dr, Highland Park IL 60035.

FINPLAN, a small business financial planning program for the TRS-80. Floppy disk, $74.95. Hayden Book Company Inc (see above).

Generate, a TRS-80 program generator. Floppy

disk, $100. DataWorks Inc, 97 Jackson St, Cambridge MA 02140.

Interactive Fiction—His Majesty's Ship Impetuous, role-playing game for the TRS-80. Floppy disk, $19.95. Adventure International (see above).

Interactive Fiction—Local Call for Death, role-playing game for the TRS-80. Floppy disk $19.95. Adventure International (see above).

Interactive Fiction—Six Micro Stories, role-playing game for the TRS-80. Floppy disk, $14.95. Adventure International (see above).

Interactive Fiction—Two Heads of the Coin, roleplaying game for the TRS-80. Floppy disk, $19.95. Adventure International (see above).

Magician's Hat, a game program for the Commodore PET/CBM. Floppy disk, $25. Southern Software Ltd, 100 Anzac Ave, POB 8683, Auckland, New Zealand.

Micro Music Audio Sampler, music composer package for the Apple II. Cassette, $5. Micro Music Inc, POB 386, Normal IL 61761.

Microtyping, touch-typing tutorial program for the Apple II. Cassette $10.95. Hayden Book Company Inc (see above).

Musical Yat-C, strategy game for the TRS-80. Cassette, $9.95. Adventure International (see above).

WE DELIVER!

n VANDAIA if

Business Software ii}

\

Before you buy the programs that your company is going to depend on for its accounting, ask the following questions:

Do I get the source (Don't settle for less.

code? You cannot make the

smallest change without it.)

Is it well documented? (The Osborne documentation is the best.)

Is it fully supported? (If not, why not? What are they afraid of?)

The Osborne system is the industry standard accounting package, with literally thousands of users. We offer an enhanced version of that package that will run on most systems without recompiling.

CRT INDEPENDENCE. The original programs were designed to run on a Hazeltine terminal. To use a different CRT, you had to modify and test two modules — and recompile every program! With the Vandata package, you simply pick your CRT from a menu and run.

FILE/DRIVE MAP. The original package had all data files on the same drive as the programs. Ours allows you to dynamically specify the drive assigned to each file. In fact, you can change the drive assignments whenever you wish, to accommodate expanded file sizes or new hardware — all without recompiling!

INTEGRATION. The original AR and AP systems had to be changed and recompiled to feed journal entries to GL. Our installation program eliminates this hassle. It simply asks you if you want the systems integrated, and what your special account numbers are.

SPEED. The original programs used a binary search to access the GL account file. We use an enhanced technique that greatly cuts down on disk accesses, thus speeding up account lookups significantly in the GL, AR and AP systems.

BUGS. We have corrected a number of bugs in the original programs. If you find a bug in our programs, we'll fix it — and send you a $20 reward! Our users are sent bug fixes in source form.

MORE! We have made many minor enhancements, and fixed many minor problems. We are committed to the ongoing support of our package. Vandata has been an independent software supplier for over seven years. Quality and support are our way of doing business.

General Ledger with Cash Journal $95

Accounts Receivable $95

Accounts Payable $95

Payroll with Cost Accounting $95

• All Four Packages (GL, AR, AP, PR) $295

Magic Wand (Super Word Processor!!) $345

Pearl Level III (best prog, tool available) $645

CBASIC-2. $110

TRS-801" MODIICP/M* 2.2 (Pickles & Trout) $185 H89/Z89 CP/M® 2.2 (Magnolia Microsystems)$249

Formats. Sid. B". 5" NorlhSlar DD. TRS-80 MOD II®. H89/Z89 Manuals lor GL. AR/AP. and PR are not included in price — add $20 per manual desired (AR/AP are in one manual) CP/M® and CBASIC-2 required to run accounting soltware Users must sign licensing agreement Dealer inquiries invited.

To order call: (206) 542-8370 or write: VANDATA

17541 Stone Avenue North

Seattle, WA 98133

CP/M° is a registered trademark ot Digital Research. TRS-80® is a registered Irademark of Radio Shack. Inc.

Circle 197 on Inquiry card.

February 1981 © BYTE Publications Inc 289

Circle 198 on inquiry card.

DISK DRIVE WOES? PRINTER INTERACTION? MEMORY LOSS? ERRATIC OPERATION?

DON'T BLAME THE SOFTWARE!

ISO-1

ISO-2

Power Line Spikes, Surges & Hash could be the culprit! Floppies, printers, memory & processor often interact! Our unique ISOLATORS eliminate equipment interaction AND curb damaging Power Line Spikes, Surges and Hash. 'ISOLATOR (ISO-1 A) 3 filter isolated 3-prong sockets; integral Surge/Spike Suppression; 1875 W Maximum load,

1 KW load any socket $56.95

'ISOLATOR (ISO-2) 2 filter isolated 3-prong socket banks

(6 sockets total); integral Spike/Surge Suppression;

1875 W Max load, 1 KW either bank $56.95

•SUPER ISOLATOR (ISO-3), similar to ISO-1A

except double filtering & Suppression .... $85.95

'ISOLATOR (ISO-4), similar to ISO-1 A except

unit has 6 individually filtered sockets .... $96.95

•ISOLATOR (ISO-5), similar to ISO-2 except

unit has 3 socket banks, 9 sockets total . . . $79.95

•CIRCUIT BREAKER, any model (add-CB) Add $ 7.00

•CKT BRKR/SWITCH/PILOT (CBS) . . . .Add $14.00

TOLL FREE ORDER DESK 1-800-225-4876

(Except Ma, HI, Ak, Pr, Canada)

££3Electronic Specialists, Inc.

171 South Main Street. Natick. Mass. 01760 Dept. B2

TECHNICAL & NON-800 AREAS 1-617-655-1532

Software Received.

TEXAS COMPUTER SYSTEMS

Radio /hack

Authorized Sales Center

All Radio Shack merchandise available at a discount. Ask for our price list.

We offer the lowest prices on

■ COMPUTERS ■

MODEL II 64K $3349 P,usS«

All accessories for Model II available — disk expansions, printers and software.

Check out our low, low prices on these fine printers:

• Amdex 9500/9501 • The New Daisy Wheel II

• Epson MX-80 * Line Printer V

• Okidata Microline 80

Special: Price our CP/M for the Model II. It offers 596 K per drive.

* Payment: Money Order, Cashier's Check, Certified Check. Personal Checks require 3 weeks to clear. VISA, MASTERCHARGE — Add 3%.

* Prices subject to change at any time.

+ No tax out-of-state. TX add 5%. * All items new, guaranteed by

manufacturer. + Delivery subject to availability.

TEXAS COMPUTER SYSTEMS

An Authorized RADIO SHACK* Sales Center F70I

Box 1174, Brady, Texas 76825

TOLL FREE Number 800-351-1473

Texas Residents 915-597-0673

PECA—Passive Electronic Circuit Analysis, electronic design utility program for the TRS-80. Cassette, $19.95. Adventure International (see above).

Pen BASIC, machinelanguage utility for Photopoint Light Pen and TRS-80. Cassette, $14.95. Micro Matrix, POB 938, Pacifica CA 94044.

PseudoDisk, a disk simulator for Apple II Integer BASIC. Cassette, $24.95, Hayden Book Company Inc (see above).

Royal Flush, poker solitaire game for the Commodore PET/CBM. Cassette, $14.95. Hayden Book Company Inc (see above).

Royal Flush, poker solitaire game for the TRS-80. Cassette, $14.95. Hayden Book Company Inc (see above).

Scramble, word-guessing game with sound for the TRS-80. Cassette, $9.95. Adventure International (see above).

Shark Attack, game for the TRS-80. Cassette, $7.95. Adventure International (see above).

Slag, multiplayer graphics

game for the TRS-80. Cassette, $14.95. Adventure International (see above).

Spelling, educational graphics game for the Apple II. Floppy disk, $21.95. Software by Witzel, 7778 S Poplar Way E, Englewood CO 80112.

Star Trek 3.5, graphics game with sound for the TRS-80. Floppy disk, $19.95. Adventure International (see above).

TRS-80 Opera, musicplaying program for the TRS-80. Cassette, $9.95. Adventure International (see above).

Tunnels of Fahad, graphics "chase" game for the TRS-80. Cassette, $9.95. Adventure International (see above).

Word Challenge, game with sound effects for the TRS-80. Cassette, $9.95. Adventure International (see above).

Z-Chess III, chess-playing program for the TRS-80. Cassette, $24.95. Adventure International (see above).

Zossed in Space, space exploration for the TRS-80. Cassette, $14.95. Adventure International (see above).■

BYTE's Bits

ing, project management,

Call for Papers

personal computing, office automation, distributed

The 1981 ACM Annual Conference is soliciting sapers for its annual conference to be held November 9-11 in Los Angeles. Technical papers should focus on innovations or recent advances and should emphasize the connection between theory and applications. Suggested topics include operating systems, programming languages, data base systems, artificial intelligence, business data processing, software engineer

systems, computer networks, computer graphics, and simulation.

Authors of papers or surveys must submit four copies of the work, typed and double-spaced, not exceeding twelve pages in length. The deadline for submission is March 7, 1981. Notification of acceptance or rejection is by May 1, 1981. Mail submissions to ACM 81—Call for Papers, Village Sta, POB 24059, Los Angeles CA 90024. ■

290 February 1981 © BYTE Publications Inc

Circle 199 on inquiry card.

Circle 201 on inquiry card.

tt Micros aren't just for games anymoreAARDVARK gets down to brass TAX. f*

AARDVARK SOFTWARE takes home computer use one practical step further with "Personal Tax," a federal income tax program designed specifically for home use.

"Personal Tax" was developed by CPA's and computer professionals. It will calculate Federal Forms 1040 and 4726, as well as schedules A, B, G and TC.The program features multiple entries for a variety of inputs (e.g. wages, dividends and charitable contributions). An indexed instruction, manual and easy-to-follow input forms are included.

"Personal Tax" computes quickly and accurately, then displays or prints the totals automatically (using a standard printer inter

face). You simply copy the totals onto your IRS forms.

This spring, use your microcomputer to simplify your taxes and file with confidence! You won't have to spend half of your refund either. The "Personal Tax" program is very affordable at only $75.

O

"Personal Tax" will run on: Apple ll,TRS-80 Models I and II, and OSI. Additionally, under CP/M, the program will run on Vector Graphics, North Star and Cromemco.

Minimum machine requirements: 48K and one disk drive. Send check or money order, or, write us for more information.

AARDVARK SOFTWARE IIMC

The M icrocomputer People for Professionals

783 NORTH WATER STREET MILWAUKEE WISCONSIN 53202 414/289-9988

(F

=\

A Message to our Subscribers

From time to time we make the BYTE subscriber list available to other companies who wish to send our subscribers promotional material about their products. We take great care to screen these companies, choosing only those who are reputable, and whose products, services, or information we feel would be of interest to you. Direct mail is an efficient medium for presenting the latest personal computer goods and services to our subscribers.

Many BYTE subscribers appreciate this controlled use of our mailing list, and look forward to finding

information of interest to them in the mail. Used are our subscribers' names and addresses only (no other information we may have is ever given).

While we believe the distribution of this information is of benefit to our subscribers, we firmly respect the wishes of any subscriber who does not want to receive such promotional literature. Should you wish to restrict the use of your name, simply send your request to BYTE Publications Inc, Attn: Circulation Department, 70 Main St, Peterborough NH D3458. Thank you.

The WORKSHEET Problem-Solving Language

Want to play "What-if".' Want to do Real Estate Analysis, Family Budgeting, Taxes, Company Cash Flow; want to simulate complex and interrelated processes'.' WORKSHEET is a powerful language designed for the purpose of writing programs to solve these and all other problems that involve a row-column "spreadsheet". Even novice programmers are solving complicated problems on the first day!

WORKSHEET is not a hybrid text editor or a toy. It is a complete, self-documenting model-building system. List the assumptions that went into your budget with the SHOWFIL program—even the bosswill understand!

Change the assumptions, the relationships, or the data, and produce a new spreadsheet, neatly captioned, in minutes.

Model too big to fit on a single page? Format it dynamically— one page of 12 (or any number) columns, or 2 pages of 6 columns, or whatever tells your story best.

Conditional evaluation of a variable? Reference to variables in different rows, several columns back? No problem!

Sample models include portfolio valuation, real estate evaluation, iterative solution of a Diophantine equation, family budget, product profit based on exponentially damped growth of sales.

Use it for tough, professional jobs—it's the only CP/ M modeling system that can handle them!

Requires 48K CP/ M system and Microsoft Basic or North Star Basic running under CP/ M with Matchmaker II.

WORKSHEET Language disk (5" or 8" CP/M). . . . S199.95

(specify Microsoft Basic version or NSBasic version) 80-Page Manual only $ 19.95

The SoHo Group

1-10 Thompson St., Suite 4-B

New York, NY 10012

Note: CI' M. Microsoft, and North Star an: registered trademarks of Digital Research. Microsoft, and North Star Computers, respectively.

Circle 200 on inquiry card.

BYTE February 1981

291

Circle 202 on inquiry card.

FULL COLOR GRAPHICS

The original 256-color imaging system with high resolution video FRAME GRABBER

for the S-100 bus. .. ,-sA

Capture and digitize a video frame in 1 /60 of a second. Select the best resolution foryour ^ application, from 256 to 1280 pixels ^tf^Lper TV line. Display your digitized ^*f£ > or computer processed image ^ ,-^ i-,:!"^ * with 256 gray levels or 256 (■>.; colors 'on stand B&W.NTSCorRG

480x512 Computer-generated

I

Compact two-board basic system

Features:

• Highest possible quality 480x512x8 digital video Image presently available on the market

• Input capability from TV camera or other sources

• Variety of synchronization choices

• 2 selectable video A/D conversion circuits

• Choice of 1, 2. 4. 8, 16 or 32 bits per pixel

• 32K-byte Image memoiy on the basic system

• 32, 64. 128 & 256K byte system capacity

• LJghtpen Input

• Photographic trigger control Input

• Software selectable system parameters

• Interfaces for TRS-80 and other processors

• Comprehensive line of accessories, monitors and support software

SEND FOR FREE CATALOG

= DIGITAL GRAPHIC SYSTEMS

e== 441 California Ave.,Palo Alto, CA 94306 415/494-6088

Send S3.00 for 11*14 reprint to: P. 0. Box 801, La Canada, CA 91011 ^Robert Tinney Graphics 1980

Books Received

An Age of Innovation, by the Editors of Electronics. New York: McGraw-Hill Publications Company, 1981; 22 by 29 cm (8V2 by HVi inches), 267 pages, hardcover, ISBN 0-07-606688-6, $18.50.

Computers and Education, James L Poirot. Manchaca TX: Sterling Swift Publishing Company, 1980; 13.5 by 21 cm (5V« by 8V* inches), 84 pages, softcover, ISBN 0-88408-137-0, $6.95.

Computer Graphics Primer, Mitchell Waite. Indianapolis IN: Howard W Sams & Company Inc, 1979; 14 by 22 cm (5Vz by 8V2 inches), 173 pages, softcover, ISBN 0-672-21650-7, $12.95.

CRT Controller Handbook, Gerry Kane. Berkeley CA: Osborne/McGraw-Hill, 1980; 18 by 23.5 cm (6% by 9V8 inches), 206 pages, softcover, ISBN 0-931988-45-4, $6.99.

Electrical and Electronics Drawing, fourth edition, Charles J Baer and John R Ottaway. New York: Gregg Division of the McGraw-Hill Book Company, 1980; 16.5 by 24.5 cm (6V2 by 9Vi inches), 432 pages, hardcover, ISBN 0-07-003010-3, $16.25.

Machine Independent Organic Software Tools (Mint), M D Godfrey, H J Hermans, D F Hendry, and R K Hessenberg. New York: Academic Press, 1980; 15.5 by 23 cm (57/8 by 9 inches), 340 pages, hardcover, ISBN 0-12-286980-X, $28.

Microcomputer Primer, Mitchell Waite and Michael Pardee. Indianapolis IN: Howard W Sams & Company Inc, 1980; 14 by 22 cm (5% by 8V1 inches), 367 pages, softcover, ISBN

0-672-21653-1, $11.95.

Microcomputer Systems and Apple BASIC, James L Poirot. Manchaca TX: Sterling Swift Publishing Company, 1980; 13.5 by 21 cm (5Yt by 8V4 inches), 136 pages, softcover, ISBN 0-88408-136-2, $9.95.

Owning Your Home Computer, Robert L Perry. New York: Everest House Publishers, 1980; 18.5 by 25.5 cm (7V4 by 10 inches), 200 pages, softcover, ISBN 0-89696-093-5, $10.95.

Programming & Interfacing the 6502, With Experiments, Marvin L De Jong. Indianapolis IN: Howard W Sams & Company Inc, 1980; 14 by 22 cm (5Vi by 8V2 inches), 407 pages, softcover, ISBN 0-672-21651-5, $15.95.

Radar & Radio Communications IC Handbook, Plessey Semiconductors. Irvine CA: Plessey Semiconductors, 1980; 14 by 22 cm (5V2 by 8V2 inches), 436 pages, softcover ISBNnone, $4.

Son of Cheap Video, Don Lancaster. Indianapolis IN: Howard W Sams & Company Inc, 1980; 14 by 22 cm (5V2 by 8Vi inches), 220 pages, softcover, ISBN 0-672-21723-6, $8.95.

Teams in Information Systems Development, Philip C Semprevivo. New York: Yourdon Press, 1980; 15.5 by 23 cm (6 by 9 inches), 126 pages, softcover, ISBN 0-917072-20-0, $16.75.

Using CP/M, Judi N Fernandez and Ruth Ashley. Somerset NJ: John Wiley & Sons Inc, 1980; 17.5 by 25.5 cm (63A by 10 inches), 236 pages, softcover, ISBN 0471-08011-X, $8.95. ■

This is a list of books received at BYTE Publications during this past month. Although the list is not meant to be exhaustive, its purpose is to acquaint BYTE readers with recently published titles in computer science and related fields. We regret that we cannot review or comment on all the books we receive; instead, this list is meant to be a monthly acknowledgment of these books and the publishers who sent them.

292 Februaiy 1981 © BYTE Publications Inc

Circle 204 on inquiry card.

To Place An Order

From Outside Texas

1-800-231-3680

MARYMAC INDUSTRIES, INC.

(Radio /hack)

Questions & Answers

& Orders Texas 1-713-392-0747

Store #G-189

AUTHORIZED SALES CENTER

BRAND NEW IN CARTONS DELIVERED. Marymac Industries owns & operates Radio Shack® dealership in Katy, Texas. Warranties will be honored by all company owned Radio Shack® stores, & participating franchisees and dealer authorized sales centers. Save State Sales Tax. Texas Residents Add Only 5% Sales Tax. Open Mon.-Sat. 10-7. We pay freight and insurance. No extra charge for Master Charge & Visa. Call us for reference in or near your city. Ref: Farmers State Bank, Brookshire, Texas. Write or visit us at, 21969 Katy Fwy, Katy (Houston), Texas 77450.

WE OFFER ON REQUEST

Federal Express 0

Houston Intercontinental Airport 0

Delivery

U.P.S. BLUE 0

References from people who have 0

bought computers from us probably in your city

In stock TRS-80 Model II and III

No Tax on Out of Texas Shipments!

ED McMANUS

Model III

10% 15%

OR MORE I

WE ALWAYS OFFER

0 NO extra charge for Master Charge or Visa

0 We always pay the freight and insurance

0 Toll free order number

0 Our capability to go to the giant Tandy Computer warehouse 5 hours away, in Ft. Worth, Texas, to keep you in stock.

JOE McMANUS

RadM /hack

In Stock

:

' o j>*—" ~»*^o(i o'o ooooooooo o'OOo&fioA&o^'

To further improve ervice to our customers we have installed a toll-free ^ WATS line in our Peterborough, New Hampshire office If you would like to order a subscription to' BYTE, or if you have a question relat ed to a BYTE subscription, you are invited to call (800)258-5485 between 8:00 AM and 4:30 PM Eastern Time. (Friday 8 AM - Noon). Calls from conti nental U.S

only. / o

joS 9178°

JLgJULO-g-g-g-g-OJLvl. ■oJCLg-B-tt.g-ft.g-PJLflJ

BYTE's

Toll-free Subscriber W.A.T.S. Line

(800)258-5485 \*

We thank you and look forward to serving you.

THE BEST OK BOTH WORLDS-EVEN BETTER NORTH STAR BASIC RELEASE 5.2-CP/M

MORE MEMORY ...BIGGER KII.ES . .. ASCII SAVE AND LOAD PROGRAM MERGE . . . COMPATIBLE WITH WORKSHEET

The "perfect marriage" between CP/ M and North Star Basic is more blissful than ever! MATCHMAKER II works with the newly available North Star Basic release 5.2. This relocatable Basic means that you can use all your system's memory! And you get files up to 2 Megabytes, two new commands (ASCSAV and ALO AD), true merging of program with interlocking or conflicting line numbers, as well as all the powerful features of the industry standard CP/M operating system. CP/ M gives you dynamic file allocation, automatic f ilecreation and extension, and automatic reuse of deleted files. What a powerful combination with the powerful instruction set of the outstanding North Star Basic interpreter, the finest microcomputer Basic available!

If you have CP/ M version 2.0 or later, the installation takes only 35 keystrokes and about 2 minutes! Don't be "DOS-bound" anotherday—leapinto the world of the pros! With Matchmaker, it's a snap!

Requires any CP/ M system and the ability to read a standard North Star diskette

The MATCHMAKER II S109.95

(specify 8" or North Star CP/ M disk)

Manual only S9.95

North Star Basic 5.2 S24.95

(supplied only on standard North Star disk)

NEW North Star FACTORY CP/ M 2.2 S229.95

WORKS WITH DD, QUAD, AND HARD DISK

ALL THREE $330.00

The SoHo Group

140 Thompson St., Suite 4-B

New York, NY 10012

Nole: CP/ M and North Slararc registered trademarks of Digital Research and North Star Computers, respectively.

Circle 205 on inquiry card.

BYTE February 1981

293

Clubs and Newsletters

Pascal/Z Users Group

The purpose of the Pascal/Z Users Group is to spread the application and use of the Pascal language. The group is offering four disks of public-domain software applicable to Z80 and Pascal/Z systems. The floppy disks cost $10 each; membership in the group is

not required for purchase. The programs are in source code and in a COM file. They include tutorials, utilities, and various applications. The group is continually seeking quality software from programmers. A bimonthly newsletter is available for $6 per year. Additional details can be obtained by writing the Pascal/Z Users Group, 7962

Center Pky, Sacramento CA 95823.

I-SUG

This group has been organized as a co-op to enable Exidy Sorcerer users to gain access to a mailing list and a user-contributed library. The library contains programs and other tech

The DS180 matrix printer provides the total package of performance features and reliability required for applications such as CRT slave copy, remote terminal networks and small to mid-range systems. Not a "hobby-grade" printer, the DS180 is a real workhorse designed to handle your most demanding printer requirements. And pricing on the DS180 is hundreds of dollars below competitive units.

High Speed Printing-Bidirectional, logic-seeking printing at 180 cps offers throughput of over 2001pm on average text. A 9-wire printhead life-tested at 650 million characters generates a 9x7 matrix with true lower case descenders and underlining. Nan-volatileFormatRetention—a unique programming keypad featuring a non-volatile memory allows the user to configure the DS180 for virtually any application. Top of form, horizontal and vertical tabs, perforation skipover, communications parameters and many other features my be programmed and stored from the keypad. When your system is powered down, the format is retained in memory. The DS180 even remembers the

line where you stopped printing. There is no need to reset the top of form, margins, baud rate, etc.it's all stored in the memory. If you need to reconfigure for another application, simply load a new format into the memory.

Communications Versatility—The DS180 offers three interfaces including RS232, current loop and 8-bit parallel. Baud rates from 110-9600may be selected. A 1K buffer and X-on, X-ofl handshaking ensure optimum throughput.

Forms Handling Flexibility-Adjustable tractors accommodate forms from 3"-15". The adjustable head can print 6-part forms crisply and clearly making the DS180 ideal for printing multipart invoices andshippingdocuments. Forms can be fed from the front or the bottom. If you would like more information on how the DS180's low-cost total printer package can fill your application, give us a call at Datasouth. The DS180 is available for 30-day delivery from our sales/service distributors throughout the U.S.

data©@i

computer corporation

4740Dwighl Evans Road • Charlotte, North Carolina 28210 • 704/523-8500

nical information for the Sorcerer. I-SUG charges neither fees nor membership dues. Clubs and individual Sorcerer users are encouraged to use 1-SUG to contact other clubs and attract new members. For complete details, send a selfaddressed, stamped envelope to I-SUG, POB 1542, St Catharines, Ontario, L2R 7J9, Canada.

Pocket

Computer

Newsletter

The Pocket Computer Newsletter reports on the latest developments concerning pocket and hand-held computers. Published ten times a year, the newsletter also features programming tips, operating time-savers, tutorial articles, notes on customizing units, programming shortcuts, listings of programs, technical information, application forums, and product reviews. The subscription price is $20 in the US, $24 in Canada, and $30 elsewhere. For information, contact The Pocket Computer Newsletter, POB 232, Seymour CT 06483.

Monroevllle Apple Users Club

This club has just recently formed. If you would like more information, write to the Monroeville Apple Users Club, attn: Dr G J Harloff, 579 Carnival Dr, Pittsburgh PA 15239.

The Cursor Group

The Cursor Group is a manufacturer-supported user group for the Bally Arcade that supports over forty affiliated local users groups. The Bally Arcade employs an enhanced version of Palo Alto Tiny BASIC, which includes analog-to-digital con

294 February 1981 © BYTE Publications Inc

Circle 206 on inquiry card.

(Let your computer play psychiatrist!)

ANALIZA is a program which simulates a conversation with a psychiatrist. You are the patient, the computer becomes the doctor.

ANALIZA is based on the famous "Eliza" program from MIT some years back, but has been greatly enhanced. It provides both entertainment as well as an interesting example of Artificial Intelligence. Below is a sample:

Patient: I have feelings of paranoia

Computer: Does it please you to have feelings of paranoia?

Patient: No it bothers me

Computer: Then why have feelings of paranoia?

ANALIZA is a match for anyone.

Requires: 48K CP/M, CBASIC2 Cost: $35.00

CP/M Formals: 8" soft sectored, 5" Northstar, 5" Micropolis Mod II, Vector MZ, Superbrain DD/QD _^^^^ All Orders and General Information:

SUPERSOFT ASSOCIATES

P.O. BOX 1628

CHAMPAIGN, IL 61820

(217) 359-2112

Technical Hot Line: (217) 359-2691

(answered only when technician Is available)

VISA

#

SuperSoft

First in Software Technology

CP/M REGISTERED TRADEMARK DIGITAL RESEARCH

Circle 209 or

inquiry card.

MICROPROCESSOR SUPPORT I.C.'S

WE GUARANTEE FACTORY PRIME PARTS

2708

1KX8

EPROM

3 Supply

450 ns

$5.50

2716

2KX8

EPROM

3 Supply

450 ns

$11.00

2716

2KX8

EPROM

1 Supply

450 ns

$11.00

2732

4KX8

EPROM

1 Supply

450 ns

$35.00

4116

16KX1

DYNAMIC

3 Supply

200 ns

8/$36.00

32/$136.00

4116

16KX1

DYNAMIC

3 Supply

300 ns

8/$32.00

32/$120.00

4164

64KX1

DYNAMIC

1 Supply

250 ns

$130.00

4118

1KX8

STATIC

250ns

EXTRA

SPECIAL $16.00

2114

1KX4

STATIC

250 ns

$4.25

8/$32.00

2114L

1KX4

STATIC

250ns

$4.50

8/$34.00

3242

$11.00

8224

$ 2.95

8255

$ 6.50

8155

17.50

8226

3.95

8259

17.95

8185

29.95

8228

5.50

8275

32.95

8202

45.00

8238

5.50

8279

13.95

8205

3.95

8243

6.00

8282

6.70

8212

2.75

8250

15.95

8283

6.70

8214

5.25

8251

6.95

8284

5.85

8216

2.75

8253

12.95

8755

49.95

TO ORDER: Send check , money order or charge card C.O.D. Please include $3.00 shipping. For C.O.D. allow for shipping and $2.00 C.O.D. fee.

HANLEY ENGINEERING

P.O.BOX 21432 SEATTLE, WA 98111 (206) 633-3404

Send for full catalog including

74XX.74LSXX and CMOS I.C's.

ECTJjfc

Building Blocks for Microcomputer Systems, Dedicated Controllers 0 0 0 and Test Equipment.

R2l/0

S-100 ROM,

RAM & I/O

BOARD

ECTs R2l/0 is an S-100 Bus I/O Board with 3 Serial I/O Ports (UART's), 1 Parallel I/O Port, 4 Status Ports, 2K of ROM with the 8080 Apple Monitor Program and 2K of Static RAM.

$295.00

RM-10 S-100

RACK MOUNT CARD CAGE

ECT's RM-10 is a rack mount 10 slot Card Cage with Power Supply, consisting of an ECT-100 rack mount Card Cage (19"W x 12.25TI x 8"D), the MB-10 Mother Board (with ground plane and termination) all 10 connectors and guides and the PS-15A Power Supply (15A @ 8V, 1.5A @ ± 16V).

$295.00

Specializing in Quality Microcomputer Hardware

Industrial • Educational • Small Business • Personal

Card Cages, Power Supplies, Mainframes, CPU's, Memory, I/O, OEM Variations

ELECTRONIC CONTROL TECHNOLOGY (2od ese-soso

763 Ramsey Ave., Hillside, NJ 07205

Circle 207 on inquiry card.

BYTE February 1981

295

Clubs and Newsletters

version, a three-voice music synthesizer, 156 by 128 resolution with up to 256 colors, and user-accessible graphics. Commands and routines not included in the documentation are published in the group's newsletter, The Cursor. Other manuals are being published. Contact The Cursor Group, POB 266, North Hollywood CA 91603.

SD User Exchange

SD User Exchange is a dealer group designed to meet the needs of the SD dealer. The group's goal is to provide an avenue for the exchange of software programs, technical knowledge, marketing tools, and ideas among SD dealers. This group was recently formed, so if you would like to become a part of this growing pool of SD resources, contact SD Systems, 3401 W Kingsley Rd, Garland TX 75041, or call Bob Sherman,

Director of Marketing, at (214) 271-4667.

Newsletter for Home Computer Users

Home Computers is a brand-new newsletter for hobbyists, investors, and the small-business person. The publication is written for home computer users who use their machines for taking inventory of collections or products, investment analysis, bookkeeping, and educational and recreational game playing. Home Computers contains equipment reviews, programming methods, a forum for input standards, coding for specific functions, and a primer for beginning programmers. Subscription information can be obtained by sending a self-addressed, stamped envelope to Home Computers, POB 616, Silverton OR 97381.

SuperLetterl

SuperLetter is for SuperBrain users. Subscribers will be able to keep pace with the latest technical news, operating tips, accessory ideas, and software designs for Intertec's machine. Regular monthly features include a technical corner, a question-and-answer forum, the latest-breaking news from the factory, guest interviews, and the SuperClassifieds. SuperLetter inquiries can be addressed to Abrams Creative Services, 369 S Crescent Dr, Beverly Hills CA 90212, (213) 277-1588.

PET Users Group

At 7:30 PM on the second Tuesday of the month, you can find the NW PET Users Group meeting in the University of Washington's Academic Computer Center, 3737 Brooklyn, in Seattle, Washington. This group is

dedicated to the use of PET/CBM microcomputers. The NW PET Users Group publishes a newsletter on a semiregular basis and it occasionally charges membership dues. Contact Richard Ball, 2565 Dexter N § 203, Seattle WA 98109, (206) 284-9417, for complete information.

Club In Venezuela

Civil Engineering students and professors at the University of Carabobo, Valencia, Venezuela, have formed a computer club. The Club de Computation Lampas de Carabobo meets on the first and second Tuesdays of each month. The primary interest is in the application of microcomputers to civil engineering practice and teaching, including basic sciences as well as administrative and technical aspects. Write to the club at Apartado 716, Valencia, Venezuela, 2001 A. ■

WHY BUY 3 COMPUTER SYSTEMS

When You Can Share Time On 1 ?

DIGIAC

III IIIIMill

MULTIPLE APPLICATION PROCESSING SYSTEMS

CT-80

i Workstation System

DIGIAC MAPS® SYSTEM FEATURES

»Three business programs can run concurrently - that's three times the

overall system productivity! >Time share word processing, accounting, order processing, inventory,

forms processing, billing and more! »Three workstations can share data base - that means preparations can

be done by several operators concurrently! » All workstations can share common peripherals.

> Uses DIGIAC AMPS - 80 operating-system. (Digital Research MP/M)

> High level language procesors including, Fortran-Basic-Pascal-Cobol. • Complete turn-key system for ease of operation and learning.

For Additional Information Contact:

MAPS

Commercial Products Division Of:

DIGIAC CORPORATION

175 Engineers Road

Smithtown, New York

11787

Phone (516) 273-8600

296 February 1981 © BYTE Publications Inc

Circle 210 on inquiry card.

Circle 212 on inquiry card.

Save on Calculators

Olympic Sales is an Hi' franchisee) dealer. Call us for the best deal.

HP-41C Scientific

189.95

Card Reader for 41C

169.95

Prinler for HP-41C

289.95

Optical WAND for 41C

109.95

Memory Module for 41C

2/95

HP-34C Scientific

119.95

HP-38C Business

119.95

HP-33C Scienlilic

7895

HP-37E Bus. Prog

63.95

HP-32E Any. Scientific

49.95

HP-67 Scientific prog

299.95

HEWLETT PACKARD

HP-85 COMPUTER

HP-97 Scieni prog priming

579.95

We have (he lowest prices on HP in America and elsewhere. Do not waste money —buy from us and save. HP-85---Graphic PlottersLetter quality printers—16K Memory modules—Software, etc. (coming soon: 8 models or Disk Drives for HP-85) HP-85 ROM.

"C" stands for continuous memory. We carry an enormous slock of HP goods and HP accessories a tall times.

Immediate delivery on all HP products in most Of the cases. One year guarantee by HP on all calcs, 90 days on computers. All units complete.

TEXAS INSTRUMENTS

TI-55 TWO TI-30 Tl 35 TI-59 TI-58C Tl 57 Prinler for 59/58C

35 95 35.95 1795 22.95 199 95 8995 49.95

149.95

Tl 58/59 Libraries

TI-5040 printer

TI-5015 prinler

TI-5100

TI-5213 comrcal prntr Callus

TI-5215 comrcalprntr Callus

TI-5217 comrcal prntr Callus

TI-5219 comrcal prntr Callus

32.95 79.95 62.95 39.95

Speak and Spell Speak and Read

Speak and Math Language Tutor Language Teacher Bus. Analyst ll Business Card Investment Analyst 48.95 NewTI 1040A 16.95

5895 74.95 67.95 129.95 79.95 43 95 39.95

Computers at unbeatable prices

Apple II

personal compukr

APPLE II Computer <*

Peripherals, accessories, software

for immediate delivery and the

lowest prices. Call us. We carry a

huge inventory of Apple Products

16K-32K-4SK. Disk Drives. Monitors,

Graphic Tablets, Pascal, Fortran,

DOS. 3.3 Silentype printers and on

and on.

We are now taking orders for Apple Id Systems. First come

first served. Call us about Apple Ml.

TEXAS INSTRUMENTS Computer 99/4 Computer console only 12" Color Monitor

*

469.95 389.95

ATARI 80016K Computer

Martel Intellivsn TV game 2609

Mattel Race Hrse Anlysr Comput

Sony Walkmn/Sndbout Sleroplyei

Sony TCS 300 Walkmn records/plays 189.95

Craig transllor doubl capac M10DSE 119.95

BSR X 10 Timer 59.95-Contrllr comnd 33.95

759.95 229.95 99.95 159.95

Sharp • S.C.M. • Royal • Victor • Canon • Casio • Pearlcorder • Sony • RCA and more.

] LA Add S4.95rorsr.ippinghandr>eldcalC5 in USA. CA residents add 6% sales tax. idvertisedpnceifihe competition hasthe goods on hand. Goods subject! a availability, st our 130 pagecatalogin writing. Call Mondaylhru Saturday. 7AM toEFM. f"

Outside CA. loll free 800-421-8045 '

Olympic sales comPAny inc.

■ CA90004 (2131381-3911 or (213) 331-1202 - Telex 67-3477

Circle 213 on inquiry card.

At last—the

Typewriter Interface!

Turn your electric typewriter into a low cost, high quality hard copy printer. 1 Year Warranty

Dynatyper—the patented" RDI—I/O Pak is fast becoming the industry standard for typewriter output. Why? Because:

1. It takes 2 minutes to initially install and 5 seconds to remove or replace.

2. You do no! have to modify your typewriter. All factory warranties and maintenance agreements on your typewriter will be honored.

3. You can use it with all powered carriage return typewriters that have U.S. keyboard. Our Model I works with all non Selectrics and our Model II works with Selectrics. Conversion between models takes 2 minutes and the kit (26 plungers) is available for a nominal charge.

4. You don't have to lug around a bulky printer when you travel. If there is a typewriter at your destination, you can install the light (3 lbs.) I/O Pak in just 2 minutes.

5. Same interface for TRS-80, Apple and GPIB. Centronics and Pet compatible interfaces are available in third quarter 1980. Electric pencil available.

6. Delivery: Stock to two weeks. Price: $499. for the complete system, FOB Rochester, Domestic.

Over 1000 in operation today. VISA and MasterCard accepted. Call Ken Yanicky at 716-244-7804, or write: "Dept. B".

3000 Winton Road South, Rochester, New York 14623 incorporated

From Ballet on Broadway

to Billiards m Dallas...

. . . people are finding unique ways to use the Powerful SciTronics REMOTE CONTROLLER

Whether it's the intricate lighting for a Broadway Ballet or the simple remote lighting of pool tables in a Dallas billiards hall, people are finding out SciTronics Remote Controller can meet their needs.

Here's Why:

0 Controls 256 BSR remote switches—not just 16 0 Hardware driven—requires minimum software 0 No ultrasonic link—prevents erratic operation 0 No BSR command module necessary

Real Time Clock gives Remote Controller an added dimension!

Real Time Clocks are now available to make your remote controller even more powerful. The RTC feature allows for energy consumption scheduling, event scheduling and much more. Your imagination is your only limitation when it comes to the ways which this RC/RTC combination can be used.

Real Time Clocks feature:

0 Lithium battery back-up

0 Crystal controlled accuracy (.002%)

0 Clock generates interrupts (seconds, minutes, hours) for foreground/background operation

0 Complete software in BASIC to Set and Read clock

$159. $159. $184.

etc)

$269. $129.

S-100 CONTROLLER BOARD S-100 REAL TIME CLOCK BOARD ENCASED CONTROLLER

(TRS-80, Apple II etc.) ENCASED CONTROLLER & REAL

TIME CLOCK (TRS-80, Apple APPLE II CLOCK BOARD

SciTronics Inc.

523 S. Clewell St., P.O. Box 5344

Bethlehem, PA 18015

(215) 868-7220 Please list system with which you plan to use peripheral. Master Charge and Visa accepted. PA residents add sales tax. COD's accepted.

Send check or money order to:

Circle 211 on inquiry card.

BYTE February 1981

297

Event Queue

February 1981

February-May

Courses from ICS, various cities throughout the US. ICS (Integrated Computer Systems) is presenting a series of intensive 3- and 4-day courses on computerized robots; interactive computer graphics; programming in Ada; structured design and programming; microprocessor software, hardware, and interfacing; computer network design and protocols; and many other topics. Contact ICS, 3304 Pico Blvd, POB 5339, Santa Monica CA 90405, (800) 421-8166; in California (800) 352-8251.

February-May

Greater Boston Area ACM Lectures, the Mitre Corporation, Bldg J, Middlesex

Tpke, Burlington MA. The Greater Boston Area Chapter of the ACM (Association for Computing Machinery) is sponsoring a series of lectures ranging from "Cryptography and Computer Security" and "Software Tools" to "The Future of Data Base Systems" and "Computer Simulation." For a schedule of times and lecture fees, contact the Greater Boston Chapter of the ACM, POB 465, Lexington MA 02173.

February-] line

The Hartford Graduate Center, Winter—Spring Courses, The Hartford Graduate Center, 275 Windsor St, Hartford CT 06120. A listing of courses from the Hartford Graduate Center is available by calling (203) 549-3600, ext 252, or by writing Don Florek at the

center. The courses offered cover hardware and software topics, along with management and theory studies.

February 9-10

Applying Single-Chip Microcomputers, Hyatt Regency Cambridge, Cambridge MA. This seminar is designed to help anyone with a basic working knowledge of computer hardware. It is being sponsored by Electronics . The fee is $445. Contact Barbara Bancroft, c/o McGraw-Hill Seminar Center, 305 Madison Ave, Rm 3112, New York NY 10017, (212) 687-0243.

February 9-13

Reliability Engineering, Testing and Maintainability Engineering, University of California, Los Angeles CA.

Introducing

THE

eericnmarK

WORD

PROCESSING

SYSTEM

THE BENCHMARK software system sets new standards in word processing. First, it can be delivered to run on the CP/M R or the North Star DOS. so there may be no need to buy a special operating system. Second, it has all the features of systems costing thousands of dollars more. Third, the price is as low as, or lower than, most word processing systems.

Anyone can learn to run and use THE BENCHMARK in one day of s'elf training. Completely self-prompting in English. THE BENCHMARK is a full capability word processor, has been thoroughly tested in an office environment and proved to meet the needs of the most sophisticated user.

• Multi-operating system

• Changes terminal drivers

• Customized to utilize all the features of terminal & printer

ONLY

$499

• Overtype - erases, corrects

• Variable, electronic decimal tab

• Screen menus simplify operation

• Block move and get

plus tax where applicable

THE BENCHMARK is distributed by R&B Computer Systems. Dealer inquiries are invited.

Dp Computer

Systems

1954 E. University 1-800-528-7385

Tempe, Arizona 85281 AZ-B02-968-7101

THE BENCHMARK is a trademark of Metasoft Corporation CP/ M is a registered trademark of Digital Research

This course is geared for engineers specializing in reliability, product assurance, logistics, quality assurance, and product design, and is designed for those who design and predict the reliability of components, equipment, and systems. The course fee is $750. Contact Continuing Education in Engineering and Mathematics, UCLA Extension, POB 24901, Los Angeles CA 90024, (213) 825-1047.

February 14-16

International Conference on Microcomputer Applications to Industrial Controls,

Jadavpur University, Calcutta, India. Papers will be presented on the applications of microcomputers to industrial controls in the areas of general systems. Contact Dr Sushil Dasgupta, Professor and Head, Electrical Engineering Department, Jadavpur University, 40B, Southern Ave, Calcutta-700029, India.

February 17-18

Integrating Word Processing and Electronic Data Processing: Technology, Architecture, Planning, The Harvard Club, New York NY. The topics of this seminar will be the study of word processing today and its future, the evaluation and selection of systems, electronic mail and communications, and the automated office. For further details, contact the seminar coordinators at the Center for Management Research, 850 Boylston St, Chestnut Hill MA 02167, attn: Ms Karen Smolens, (617) 738-5020.

February 18-20

Business- and PersonalComputer Sales and Exposition and the Houston Business Show, Houston Civic Center, Capitol Ave and Bagby St, Houston TX. Data-processing managers, systems analysts, programmers, educators, hobbyists,

298 February 1981 © BYTE Publications Inc

Circle 214 on inquiry card.

Circle 216 on Inquiry card.

Circle 217 on inquiry card.

TOLL FREE ORDERING

These Fine Products and More

NORTHSTAR

HRZ 1-32K-D $1990

HRZ2-32KD 2295

HRZ 2-32KQ 2690

HARD DISC SYSTEM 3935

DYNABYTE

DB8/148K $2395

DB 8/2 48K 3900

DB 8/4 3030

32M PHOENIX 11800

TERMINALS

TELEVIDE0 912C 698

TELEVIDEO920C 748

SOROClQ-120 695

PRINTERS

NEC 5510 (w TRACTORS). . 2575

N EC 5520 (w TRACTORS). . 2900

TI-820 1640

TI-810 1495

ANADEX DP-9500 1345

CENTRONICS 737 850

EPSON TX80 CALL

MORROW

DISCUS 2D 2 DRIVE 1550

DISCUS 2 + 2 1 DRIVE 1265

DISCUS M26 HARD DISC. . 3990 SOLID STATE MUSIC KITAsm

CB2Z80CPU 200 265

VB1C VIDEO 140 190

SB1 SYNTHESIZER . . . 195 270

MEASUREMENT SYSTEMS MEMORY

DM3200 32K4MHZ 480

DM6400 64K 4MHz 595

DMB6400 64K 4MHz

BNKSEL 745

SOFTWARE-DISCS

NORTHSTAR SOFTWARE .CALL

WORDSTAR 350

DATASTAR 250

MAGIC WAND 290

GRAHAM-DORIAN CALL

STRUCTURED SYSTEMS . .CALL

5" DISCS 27

8" DISCS 35

WE WILL TRY TO BEAT ANY ADVERTISED PRICE

Automated Equipment Inc.

18430 Ward Fountain Valley, CA 92708

(714)963-1414 (800)854-7635

10& A BASIC A+

to* * FROM THE AUTHORS OF ATARI® BASIC

€9

BASIC A+ for the ATARI 800® BASIC A+ will rate an A+ from any Atari user! Upward compatible with Atari Basic, it adds statements and leatures that enhance the Atari 800's real power, flexibility, and ease of use: Superior I/O features for business and other applications. Additional file manipulation commands. Significant help in program development and debug. Structured programming aids. And MORE! A partial list of the enhancements of BASIC A+ includes:

PRINT USING (for business, sophisticated)

RPUT/RGET (record I/O) SET TAB

BPUT/BGET (binary I/O) INPUT"..." OIR

ERASE PROTECT RENAME TRACE

WHILE... ENOWHILE IF...ELSE...ENOIF

MEANINGFUL ERROR MESSAGES

BASIC A+ requires a disk and 32K bytes of RAM. Since

no cartridge is used, BASIC A+ will take advantage of

all the RAM (48K bytes) in a maximum Atari 800 system

(recommended).

CP/A® for the ATARI 800

Simple. Flexible. Powerful. Compatible. A command driven DOS Control Program that allows user-written commands, ease of interface, and total compatibility with all devices and features of the Atari DOS and file system. Using less room than a menu-driven DOS, CP/A allows utilities to be dynamically accessed from disk as needed.

Powerful Utilities INCLUDED with CP/A'"

All the following utilities are included in the price of CP/A, but you can easily add your own for even more flexibility and power.

EDITOR/ASSEMBLER/DEBUG EASMO is a simple but complete all-in-one assembly language development package for the 6502 microprocessor. The editorprovides global functions such as FIND and REPLACE (with optional query!) and can be used to edit BASIC A+ programs. The assembler supports standard 6502 mnemonics; can include multiple files in a single assembly; outputs the listing to printer, screen, or disk; produces readable error messages and a flagged symbol table; places the object code in memory or to a disk file. The object code produced is compatible with Atari DOS or Apple DOS (BLOAD) as appropriate. The debug capabilities include STEP, TRACE, mini-assembler, disassembler, and more.

DUPDSK and FORMAT

Allows creation of master disks, slave disks, and sector-by-sector copies of any CP/A disk.

COPY

Single file copy utility. Destination can be disk, screen, printer, or any device.

PARTIAL SOURCE CODE

For system equates and some system drivers. Customize your system.

BASIC A+ for the APPLE II®

All the features* of our Atari BASIC A+! Includes the advanced commands and programming aids that make Atari Basic flexible, easy-to-use, and powerful: DECIMALARITHMETIC(10digitstothe penny) SYNTAX CHECK ON PROGRAM ENTRY LONG VARIABLE NAMES (all chars, used) STRINGS UP TO 32K BYTES IN LENGTH SEMI-COMPILED CODE (no penalty for those long names) BASIC A+ requires and takes advantage of all the features and power of CP/A.

'Some Atari hardware related leatures cannot be supported on the Apple II.

CP/A^ for the APPLE II® A DOS with a DOCUMENTED assembly language interface! Simple. Elegant. Upward compatible with the file systems of Apple's DOS 3.2 and 3.3 but with flexibility not available until now. Add your own commands. Add your own device drivers. Easy FAST random access from assembly language or BASIC A+. Requires 48K RAM and one disk drive.

ORDER TODAY!

All software is licensed for single system use only. PLEASE SEE YOUR DEALER FIRST. If he cannot supply you, ordering info is below. DEALER AND DISTRIBUTOR INQUIRIES INVITED.

CP/A and BASIC A+ are trademarks of Shepardson

Microsystems. Inc. APPLE and APPLE II are registeredtrademarks of Apple Computer, Inc. ATARI and ATARI 800 are registered trademarks of Atari. Inc.

Shepardson Microsystems, Inc.

20395 Paciflca Dr., Suite 108

Cupertino, CA 95014

(408) 257-9900

CP/A

Atari .... S 80

Apple

S 80

BASIC A+

CP/A & BASIC A+

S 80 S150

N/A S150

Add $5 per package shipping

in U.S. 6% tax

in CA.

BYTE February

1981

Circle 218 on Inquiry card.

299

Event Queue

and user's groups will find this exposition useful. The business show is primarily designed for purchasing and office managers, executives, business owners, attorneys, accountants, and physicians. For details, contact Produx 2000 Inc, POB 2000, BalaCynwyd PA 19004, (215) 457-2300.

February 23-26

Computer Science Con- , ference, Stouffer's Riverfront Towers Hotel, St Louis MO. The conference is sponsored by the ACM (Association for Computing Machinery). The Ninth Annual Computer Science Employment Register will be conducted. This register aids in matching computer scientists and data-processing specialists with employer opportunities. For information, contact Orrin E Taulbee, ACM Computer Science Employment Register, Department of Computer Science, University of Pitts

burgh, Pittsburgh PA 15260, (412) 624-6475.

February 24-25

The Ninth Annual Midwest Digital Equipment Exhibit and Seminar, Thunderbird Motel, Minneapolis MN. More than sixty manufacturers of computer terminals, data-communication equipment, peripherals, and test instruments will be displaying their products. Over 1500 users and manufacturers are expected to attend. Registration at the entrance area is required, but there is no charge to attend exhibits or seminars. Contact Kim Shobe, c/o Loonam Associates Inc, 7720 Bush Lake Rd, Minneapolis MN 55435, (612) 831-1616.

February 26-27

Louisiana Computer Exposition, University of Southwestern Louisiana, Lafayette LA. Papers will be read on operating systems, data-base management and support, distributed com

puters systems, and related topics. Contact William R Edwards, c/o the Computer Science Department, University of Southwestern Louisiana, POB 44330, Lafayette LA 70504, (318) 264-6284.

March 1981

March-November

Advanced Data Processing Workshops, Deltak Inc, various cities throughout the US and Canada. These 5-day workshops are aimed at data-processing training managers responsible for the management and administration of data-processing training and involved in planning, monitoring, evaluating, and reporting to upper management on the status of the training. For a schedule of dates and locations, contact Deltak Inc, 1220 Kensington Rd, Oak Brook IL 60521, (312) 920-0700.

March 8-11

TI-MIX 1981, Marriott Hotel, New Orleans LA. This is a conference for Texas Instruments equipment users. Thirty-six sessions consisting of individual presentations, panel discussions, and workshops are planned. Two exhibit rooms featuring the latest computer equipment from Texas Instruments will be open. Contact TI-MIX, M/S 2200, POB 2909, Austin TX 78769, (512) 250-7151.

March 11-13

Business- and PersonalComputer Sales and Exposition and New York Business Show, Madison Square Garden, New York NY. See February 18-20 for details.

March 17-20

The Fourteenth Annual Simulation Symposium,

Tampa FL. Papers describing digital discrete simulation and other techniques will be read. This symposium is a

XT4T TNFTWR CI OPl^ PT T TQ™ PUT TIME AND REMOTE

± n. \*J L^i I_-H^IY\^l>W\^IV L 1> ^O CONTROL IN YOUR APPLE II

The THUNDERCLOCK PLUS is two peripheral systems on one card for your APPLE II OR II PLUS. An accurate, reliable, real-time clock/calendar and an interface for the popular BSR X-10 Home Control System.

The THUNDERCLOCK clock/calendar makes accurate time and date available to your programs: month, date, day-of-week,

hour, minute, and second, in any of four software selectable formats. On-board batteries keep your THUNDERCLOCK

running when your APPLE II is turned off - for up to four years before battery replacement.

On-card IK firmware makes reading or setting the time easy from APPLESOFT or INTEGER ^sUf^'

BASIC, PASCAL, or assembly language programs. And it provides software selectable

interrupts at any of three rates: 64, 256, or 2048 interrupts/second.

THE PLUS |H^a

Add THUNDER WARE'S X-10 ULTRASONIC INTERFACE OPTION to your

THUNDERCLOCK and your programs can send all 22 BSR X-10 commands so you can

remotely control lights and appliances. A full 128 dim/bright levels. And a powerful disk

software package! The THUNDER WARE SCHEDULER software lets you create schedules to

control lights, appliances, security systems, or almost any other electrical device. The software

includes: SCUTIL- the SCHEDULER utility that lets you make or change a schedule, and SCHED- executes your schedules in

real-time using the THUNDERCLOCK. SCHED runs in the 'background' so you can run other programs in the 'foreground'.

The THUNDERCLOCK PLUS is a SYSTEM for your APPLE II. Supported by intelligent, easy to use firmware, a powerful

software package, and good documentation!

Availai-ilp rrirmiori vmir rlpaW Suggested retail prices:

Available mrougn your dealer. thunderclock plus $139 „ . , . ,

,-,.,,,, j ,iL « _ , It your dealer doesn t carry the

',"%: E383E3WS3i^& CIoc,k/calendar card w,th bat,er,es and thunderclock plus:

I user s manual ORDER TOLL FREE (V1SA/MC) CALL:

X-10 INTERFACE OPTION $49 800-227-6204 EXT 307 (Outside California)

1|»»^^»^^^S^ BSR X-10 Ultrasonic interface, disk with 800-632-2131 EXT 307 (California Only) SCHEDULER SOFrWARE &. demos, and WS^: j user's manual

I PASCAL SOFrWARE $29 OR WRITE TO:

I Disk with PASCAL interface for clock and

M§T X-10 interface, and user's guide THUNDER WARE INCORPORATED

bsr x-io i.» trademark of bsr (USA) ltd. MANUALS ONLY, each $5 P.O. Box 13322, Oakland, C A 94661

APPLE 11 is a trademark of APPLE COMPUTER, INC California residents add 6% sales tax

300 February 1981 © BYTE Publications Inc

Circle 215 on inquiry card.

Circle 220 on inquiry card.

Circle 221 on inquiry card.

Selectric® Interface System

.ASILY interfaced to any IBM Selectric I, II, or III.

^5TOP spinning your wheels. Letter quality at an affordable price.

V^ONNECTS via Parallel or RS-232, accommodates varied handshaking.

'NLY $575 to $599. Dealer inquiries invited.

ECHO SERIES™speech synthesizers

COMPUTERS ARE SPEAKING OUT!

Now you can add intelligible speech to your computer without using vast amounts of memory! The ECHO ] [™ speech synthesizer for the Apple* is the first of a series of synthesizers based on the same technology that made the Speak & Spell** a success.

The initial operating system allows the creation of your own vocabulary with phonemes (word sounds) while using very little RAM memory (approx. 800 bytes + 20 bytes/word). Enhanced operating systems and vocabulary ROMs will be offered as they become available.

The ECHO ][™ comes complete with speaker, instruction manual, and a disk containing a speech editor, sample programs, and a sample vocabulary. Sug- I gested list price is $225.

See your dealer or contact:

liiiiiniiniiimnn

ISECj

STREET ELECTRONICS CORPORATION

3152 E. La Palma Ave., Suite C Anaheim, CA 92806 (714)632-9950

*Trademark of Apple Computer ** Trademark of Texas Instruments

Circle 219 on inquiry card. *

Event Queue

forum for the exchange of ideas and techniques in computer simulation. Contact Annual Simulation Symposium, POB 22621, Tampa FL 33622.

March 20

Digital Computer Association Annual Meeting, Pacifica Hotel, 6161 Centinela Blvd, Culver City CA. Cocktails, dinner, and the annual meeting are the features of this gathering. For more information, contact Mary Rich, 731 Bayonne St, EI Segundo CA 90245.

March 23-25

Office Automation Conference, Albert Thomas Convention Center, Houston TX. This conference will present seminars on concepts and methods behind the latest office technologies and an exhibition of office equipment. Contact Office Automation Conference, POB 9659, Ar

lington VA 22209, (703) 558-3617.

March 24-26

The Southwest Semiconductor Exposition, Phoenix Civic Plaza Convention Center, Phoenix AZ. More than 140 equipment and materials makers will exhibit semiconductor, hybrid, and printed-circuit board production, processing, and test equipment. Contact Cartlidge & Associates Inc, 491 Macara Ave, Suite 1014, Sunnyvale CA 94086, (408) 245-6870.

March 31-April 2

Cincinnati Business Show,

Cincinnati ConventionExposition Center, Cincinnati OH. Office equipment and services, including automated systems, communications, computers, telephone systems, word processing, data processing, printing equipment, and other office supplies, will be featured. A program of

ENERGY SOFTWARE

for engineers, designers, builders, etc.

PASSIVE SOLAR DESIGN: direct gain, sunspaces, trombe & water walls

PASOOE 1: Los Alamos SSF correlation model

with economics computerised $295

EXFIND/LPMTZ: Hourly simulation models for assessing building energy load dynamics and economics of passive design $395/695

OVERHANG: A 2-dimensional overhang shading

design program $195

CONSERVATION DESIGN: assessenergyfrom s component or system level

BILL: Correlation of a buildings energy bills and

weather for conservation assessment . . . $295

INSULATE: Building surface insulation optimization

and economics package $195

Programs available: TRS-80, APPLE II, CPM ICSASIC2, MICROSOFT),

NORTHSTAR, ALPHA MICRO. Orders: Prepaid/C.O.D. — 20% discount on 2 or more packages

7438 FORSYTH, SUITE 202

LONDE 'PARKER 'MICHELS ST. louis, mo.63106

13141 7255501

business seminars is also scheduled. Contact Ray G Nemo, 5679 Creek Rd; Cincinnati OH 45242, (513) 531-5959.

April 1981

April 1-3

Assuring Quality in Electronic Data Processing Applications, McCormick Inn Hotel, Chicago IL. The objective of this conference is to explain the methods, tools, and techniques that are valuable in improving the quality of computerized applications. Tutorials will cover the areas of quality assurance; managing structured design; and designing, implementing, and enforcing application standards. Contact DPMA Quality Assurance Conference, 12611 Davan Dr, Silver Spring MD 20904, (301) 622-0066.

April 3-5

The Sixth West Coast Computer Faire, Civic Auditorium, San Francisco CA. The Faire, a major personal-computing event, has continually attracted larger and larger numbers of exhibitors and attendees. A full program of talks plus a large display of hardware and software are featured. For more information, contact Computer Faire, 333 Swett Rd, Woodside CA 94062, (415) 851-7075.

April 7-8

Top Secrets '81, Pointe Resort, Phoenix AZ. Honeywell's annual computer security and privacy conference. Many authorities in the field of data security will discuss the business and legal impact of the latest incidents in computer crime and abuse. The conference fee is $500. Contact the Security Symposium Registrar, Honeywell Information Systems, M/S T-99-4, POB 6000, Phoenix AZ 85005, (800) 528-5343.

April 7-9

Computerized Office Equipment Expo, O'Hare Exposi

tion Center, Rosemont IL. Over 200 exhibitors will be featuring their office equipment at this show. Executives and administrators from wholesale, retail, commercial, financial, and industrial establishments are invited, along with the general public. Contact Industrial & Scientific Conference Management Inc, 222 W Adams St, Chicago IL 60606, (312) 263-4866.

April 7-9

Electro/81, New York Coliseum and Sheraton Centre Hotel, New York NY. Electro/81 will feature computers and computer-related equipment, plus seminars on components, devices, and materials; computer communications; memories; office automation; speech; and more. Contact Electronic Conventions Inc, 999 N Sepulveda Blvd, Suite 410, El Segundo CA 90245, (213) 772-2965.

April 13-16

The Fifteenth Annual Symposium on Minicomputers and Microcomputers, MIMI '81, Sheraton Hotel, Mexico City, Mexico. This symposium covers hardware, software, distributed processor architecture, computer networks, telecommunications, real-time applications, education, and more. Contact Ing. Jorge Gil, Academic Secretary, MIMI Symposium, IIMASUNAM, Apartado Postal 20-726, Mexico 20 D F, Mexico.

April 26-30

Saudibusiness '81, Riyadh, Saudi Arabia. This show has been designed for the fastgrowing Saudi Arabian business community. Pavilions by the United States, the United Kingdom, West Germany, France, Italy, and approximately fifteen other countries will be featured. For more information, contact Donald Ryan, Project Manager, Rm 3200, US Department of Commerce, Washington DC 20230, (202) 377-4652. ■

302 February 1981 © BYTE Publications Inc

Circle 222 on inquiry card.

Circle 224 on inquiry card.

Circle 225 on Inquiry card.

GO FOR IT!

FOR PRICE,QUALITY& RELIABILITY

ADDS REGENT 25 $ 925.00

ANACOM Printer (Ser./Par.) 150CPS .... 1095.00

ANADEX Printer DP-8000 925.00

ANADEX Printer DP-9500/9501 '. 1375.00

BASE 2 Printer with options 599.00

CENTRONICS Printer 779 w/tractor 975.00

CENTRONICS Printer 730 (Parallel) 675.00

CENTRONICS Printer 737 (Parallel) 825.00

EATON Dot Matrix Parallel 399.00

EPSON TX80 Tractor Feed/Graftrax .... Call

MICRO-TERMS Call

NEC SPINWRITER 5510 R.O./forms tractor 2725.00

TELEVIDEO 920-B 795.00

Tl 99/4 Personal Computer/monitor .... 925.00

TRIMM-Printer Stand with basket 95.00

CALL FOR QUOTES ON ANY OTHER MICRO PRODUCTS

We are dealers for BASF, DYSAN, 3M(SCOTCH) Diskettes, Cartridges, Mag Tape, etc. In addition we carry a complete line of Printer Ribbons and other data processing accessories.

[—m^-^Jimm\ 1840 LINCOLN BLVD.,

llllCr1/"! SANTA MONICA, CA 90404 lUlflLf JJ (213) 450-5911 (call collect)

MART, INC PRICES SUBJECT TO CHANGE

Clock/Calendar

Now available on Three Buses

Features *APPLE II

• 12/24 Hr. Format

• Month-Day-Year

• Day of Week * TRS-80

• Leap Year Bit

• 4 Interrupts <^

• +-30Sec.Adjust\

• Battery Backup

• Simple to Program

S100

S-100 or Apple

A&T S150

Kit S100

Bare Bet S 60

TRS-80

A&T Only S150

LAX COMPUTER PRODUCTS

4728 Manhattan Beach Blvd. Lawndale, CA 90260 (213)970-1759

WE ACCEPT

VISA, MC & AMER. EXP.

Apple is a Trademark of Apple Computer Co.

TRS80 is a Trademark of Tandy Corp.

Omikron's Mapper + NEWDOS/80 8 Drives for the TRS-80

NEWDOS/80 is Apparat's latest upgrade to NEWDOS. Features include variable length records, chaining, and drivers specifically configured for Omikron's MAPPER II. $150.

MAPPER II adapts the TRS-80 to run both 5" and 8" drives. With NEWDOS/80, storage is increased to 300K per 8" drive. $99 plus $10 per cable connector.

MAPPER I adapts the TRS-80 to run the vast library of CP/M software as well as the TRS-80 software. All Lifeboat Software may be ordered forthe MAPPER I. All MAPPER I CP/M software is compatible with the CP/M forthe Model II. With MAPPER II and 8" drives, the Model I becomes disk compatible with the Model II.

Standard features include lowercase support, serial and parallel printer drivers, and an addressable cursor. MAPPER I is supplied with complete utilities including a memory test, a disk test, a copy program, and a proprietary program for converting TRS-DOS files to CP/M files. $199.

WORD PROCESSING-MAPPER I supports professional word processors like the Magic Wand and Word Star (see reviews in June 80 Kilobaud). Omikron's implementation includes a blinking cursor, auto repeat, shift lock, debouncing, and an input buffer that eliminates missed characters. Magic Wand super discount price $299.

FIELD PROVEN DESIGNS-After one year of MAPPER production, Omikron has established an impeccable reputation for reliability, integrity, and user support. Omikron's customers include the US Government, major corporations, universities, medical doctors, and professionals in all fields.

SYSTEMS —Omikron sells complete systems featuring Model II compatible Shugart disk drives. Call for prices and delivery.

FOREIGN ORDERS must include full payment in US funds plus $25 for air shipping and handling.

See review in July 80 BYTE By Jerry Pournelle.

*CP/M isaTM of Digital Research. TRS-80 is a TM of T

andy Corporation.

Circle 223 on inquiry card.

Book Reviews

Writing Interactive Compilers and Interpreters

P J Brown U/iley Interscience New York, 1979 256 pages, hardcover S26.95

Reviewed by Paul Chisholm 209 Bernard Ct Madison Wl 53715

There are two important aspects of compiler writing. One is that compilers are big programs, and big programs are very difficult to write. (A thousand-line program is considerably more than ten times as difficult to write as a hundred-line program.) The other aspect is that there are many well-known techniques for translating or interpreting programs. Brown's book deals with this aspect. He assumes you are able to program in a highlevel language (such as Pascal) and that you have had some experience with an interactive language (preferably BASIC).

Brown discusses the fundamentals of compiler writing. He strongly emphasizes interactive programming languages, like BASIC, where programs are developed one segment at a time, as opposed to being carefully edited and put through a compiler. He also assumes that most of his readers are working with single-user microcomputer systems which have limited memory. Therefore, he often mentions ways to squeeze a few extra bytes from the programs; but he does not worry very much about speed.

The book is divided into eight parts. They deal with planning of the project, the overall structure of the compiler (including the internal representation language, error checking, symbol tables, storage management,

304 February 19B1 © BYTE Publications Inc

and such), the internal language (most often Reverse Polish Notation), parsing and translation, the run time system, other modules, compiler testing, and advanced topics.

Throughout the book, Brown emphasizes the modular approach—designing, coding, and testing the system one piece at a time. He spends much time on the recreation of programs from the internal representation. For instance, if the BASIC you use sometimes inserts or drops spaces in your statements, it is because the editor within the BASIC system does not store your program the way you typed it in. Instead, it stores it in its own internal representation. Unless you also want to store the program exactly as it was entered, using a total of twice as much memory, you need a way to recreate the program from the internal representation. Brown also discusses incremental compiling—compiling a program a segment at a time. (If the version of BASIC you use translates each line as it is typed in, it is doing incremental compilation.) And Brown talks about handling what he calls "break ins"—what must be done after you hit the break or reset key. There is a very complete index, and an excellent bibliography.

Brown does not say much about the other major aspect of compiler writing—how to write very large programs. However, he suggests several "deadly sins" to avoid. He recommends the book Software Tools, by Brian Kernighan and P J Plauger, for more on this subject.

If you have had some experience with writing very large programs, Writing Interactive Compilers and Interpreters has all you need to know to write a compiler or interpreter that handles BASIC, PILOT, or Logo (or even APL or LISP). It is a little weak for handling more complex languages

#10 SOFTWARE

\S new items/new prices.

FANTASTIC PRICE PROTECTION POLICY

We'll match any advertised price on any item that we carry. And if you find a lower price on what you bought within 30 days of buying it, just show us the ad and we'll refund the difference.

It's that simple.

Combine our price protection with the availability of full professional support and ourautomatic update service and you have the Ultimate Software Plan.

It's a convenient, uncomplicated, logical way to get your software.

CP/M users: specify disk systems and formats. Most formats available.

CP/M'

OSBORNEH °"

General Ledger*. . . .$ 59/$20 Acct Rec/Acct Pay*. .1 59/$20

Payroll w/Cost* $ 59/S20

Buy 2 get 1 free $118/$57

AII3&CBASIC-2 $199/$71

DIGITAL RESEARCH

CP/M 2.2 Northstar.. .$149/525

s CP/M 2.2 Micropolis...$169/$25

t' CP/M 2.2 Durango

F-85 $169/$25

CP/M 2.2 Cromemco $189/525 CP/M (other versions) Call

*- PL/l-80 $459/535

Mac 5 85/$ 15

Sid $ 65/$15

Z-Sid $ 95/$15

Tex $ 70/$ 15

DeSpool $ 50/$10

MICROSOFT

Basic-80 5294/530

Basic Compiler 5334/530

Fortran-80 5384/530

s Cobol-80 $574/$30

Macro-80 .$144/$20

Edit-80 $ 84/520

MuSimp/MuMalh $224/$25

,s MuLisp-80 $174/$20

MICRO DATA BASE SYSTEMS

HDBS $250/$40

MDBS $750/$40

Other Call

S.O.F.T.W.A.R.E.

MicroTax't

Federal individual $749/$50

Federal corporate $249/$25

State individual $249/$25

TCSt

• General Ledger $ 79/$25

^ Acct Receivable. $ 79/$25

s Acct Payable $ 79/$25

s Payroll $ 79/$25

*• All 4. $269/$99

SUPERSOFT

Forth (8080 or Z80) 5129/525

Diagnostic I. $ 49/$20

Other disk software .... less 10% SOFTWARE WORKS

Adapt $ 69/ na

Ratfor $ 86/ na

COMPUTER PATHWAYS

Pearl (level 1)#. $ 99/$25

Pearl (level 2)*. . .5299/525

Pearl (level 3)# $549/$25

COMPLETE BUSINESS SYSTEMS}

^Creator $269/$25

*■ Reportor $169/$20

,<- Both $399/$45

MICROPRO

WordStar. $324/$40

Mail/Merge $114/$25

THIS MONTH'S SPECIAL: TIM. DBMS JUST S299.

Terrific for inventory, mailings, financial, you-name-it! Menudriven, auto-sort, 32000 records per file, any number of files, and dynamite documentation!

WordStar/Mail-Merge .$434/$65

DataStar $279/$35

Word-Master $119/$25

SuperSort I $199/$25

SuperSortll $169/$25

SuperSort III $119/$25

PEACHTREE'Ht

General Ledger $399/$40

Acct Receivable $399/$40

Acct Payable $399/$40

Payroll $399/$40

Inventory .$399/$40

Property Mgt $799/$40

C.RA. Client Write-up. .$799/$40

Mailing Address $349/$40

STRUCTURED SYSTEMS

GLorAR or AP# $747/$25

Payroll* $747/525

InventoryControl* .5447/540

Analyst* $197/$20

Letteright* $167/$20

NAD# $ 87/$20

QSORT .$ 87/$20

GRAHAM-DORIANH

General Ledger* $693/$40

Acct Receivable# $693/$40

Acct Payable* .5693/540

Job Costing* $693/$40

Payroll* $493/$40

Inventory* $493/$40

Cash Register* $493/$40

Apartment Mgt*. .... .5493/540

MICRO-AP

Selector III-C2* $269/$20

Selector IV* $469/$35

.' S-Basic $269/$25

WHITESMITHS

"C" Compiler* $600/530

Pascal(fncl"C")* ... $750/$45 EIDOS SYSTEMS

Kiss .$299/$25

K-Basic $529/$50

ORGANIC SOFTWARE TextWriter III $111/$20

S DateBook $269/525

SoHo Group

k« MatchMaker, $ 84/$io

.•'Worksheet $124/$20

• OTHER GOODIES'

Tiny ■C" $ 89/$50

k< Tiny "C" Compiler $229/$50

CBASIC-2 $ 89/$ 15

Pascal/Z. .$369/$30

Pascal/UCSD $299/$30

Pascal/MT+ $224/530

Pascal/M $149/520

Nevada Cobol 5129/525

s Raid 5229/525

,-- MAGSAM III 5129/525

,-- MAGSAM IV 5259/525

S BSTAM 5129/510

FMS-80 5649/545

dBASE II DBMS 5629/535

Condor DBMS 5599/530

Vulcan DBMS 5469/530

T.I.M. DBMS* 5329/535

CBS 5369/545

Whatsit' 5 149/525

^ Ultra-Sort II 5159/5 25

p- MicroStat 5224/515

String/80 $ 84/520

s Vedit $ 99/515

Postmaster 5149/520

^ WordSearch $ 179/$25

./- SoellGuard $269/$25

Spell Binder $349/545

./- VTS/80 5489/565

MagicWand 5299/545

Electric Pencil II less 15%

CPAids less 12%

APPLE IIs

MICROSOFT

Softcard(CP/M) 5292

Cobol Call

PERSONAL SOFTWARE

VisicalC .$122

CCA Data Mgr 5 84

Desktop/Plan $ 84

<s Zork. Call

PEACHTREE-HJ

General Ledger 5224/540

Acct Receivable. , . ,.5224/540

Acct Payable $224/540

Payroll 5224/540

Inventory 5224/540

MUSE

Super-Text II 5127

Other disk software. . . less 10% STC (Software Tech.)

s Prof.Time& Billing . $279

Other less 15%

OTHER GOODIES"

K* Data Factory $ 79

Whatsit?" $129

y Creator $229

S LedgerPlus

(GL A/R & A/P) . , . $549

TRS-BO" MODEL II

CP/M 2.2 (P&T) $159/$35

Electric Pencil II less 15%

NORTHSTAR

s NorthWord S299

s Mail Manager $239

is Info Manager $369

y General Ledger $749

i'' Acct Receivable $449

f Acct Payable $449

♦ — Special Bon

t-Reauiresmicrosoft BASIC H-Supplied in source code s-Reauires CBASIC-2 R—Mtgs Trademark

ORDERS ONLY-CALL TOLL FREE VISA • MASTERCHARGE

1-800-854-2003 ext. 823 • Calif. 1-800-522-1500 ext. 823

Overseas—add $10 plus additional postage • Add $2.50 postage and handling per each item • California residents add 6% sales tax • Allow 2 weeks on checks. C.O.D. ok • Prices subject to change without notice All items subject to availability •

THE DISCOUNT SOFTWARE GROUP

1610 Argyle Ave., Bldg. 102 ■ Los Angeles, CA 90028 • (213) 666-7677

Circle 226 on Inquiry card.

February 1981 © BYTE Publications Inc 305

Buy From CMC International, The

SUPRBR/MN

SPECIALISTS

TO ORDER CALL 1-800-426-2963

SUPRBRAIN

64K

SIngle-slded. double denslly. Retail $3345.

Double-sided, double denslly. 720k byles slorage. 64k RAM Retail 53995.

2550 '3245

COMPUSTAR

Intertec's new multi-user system

Model 10. . . Sugg. List $2495 Call tor price

Model 15 $1995 Call for price

Model 20 $3995 Call for price

Model 30 $4495 Call for price

Model 40 $4995 Call for price

HARD DISCS

Intertec's Winchester Type 8" hard disk for Superbrain or Compustar Terminal

10mb Sugg List $4995. Your Cost $3890

Call for prices on 32 mb and 96 mb hard disks.

TERMINALS

Intertube III. Emulator

Sugg. List $895 $895

Your Cost $750 $750

SOFTWARE

CBosic MBasic

Account Receivable Accounts Payable General Ledger Payroll Inventory

Restaurant Payroll Job Costing Client Billing Mailing List (NAD) Moster Tax Package (CP Aids) Restaurant Cost &

Inventory Program Medical Billing Dental Billing Cash Register

Inventory Program

Reg. Cost

$750 $350 $750 $350 $750 $350 $750 $350 $750 $350 $750 $350 $750 $350 $750 $350 $150

$1500 $995

$750 $350 $1000 $899 $1000 $899

$750 $500

LOOK AT OUR PRINTERS & PRICES!

VISTA V-300

Daisy wheel printer, 25 cps

Retail CMC $1ARft

$1895 Price !■?»**/

VISTA 45 cps

$1750

Retail CMC $2195 Price.

EPSON MX-80

Parallel, multi-column, 80 cps, disposable print head Retail $645

CMC Price S555

DOT MATRIX

All printers with RS 232

MPI 88TReg $749

MPI 88 GReg $749

Graphics option odd $50

PAPER TIGER 440 Reg $995 .

440 w/graphics & 2k Buffer. .

Tl 810 Reg. $1895

Tl 810 w/full ASCII Reg.$2155 .

s595 s650

s895

s985

$1650

s1950

C. IT0H

Daisy wheel starwriter, 25 cps, one year warranty Retail S1895

CMC Price

s1450 45 cps MODEL

CMC Price S1750

WORD PROCESSING

Magic Wand Reg $400.... s325

VTS-80 Reg $549 S469

WORD STAR Reg $495. . . s400 WORD STAR/MAIL MERGE. . . .'515

{LINK 80 '89

[CAT Novation Modem '169

DAISY WHEEL or THIMBLE

XYMEC Reg $2875 $2530

QUME 5/45RO Reg. $3073 .... '2695

KSR Reg. $3537 s3145

With tractor Reg. $3787. . .'3350

DIABLO 630 R0 Reg $2950. . '2180

RO with tractor. Reg.$3250 . '2380

ANADEX DP 9500 or 9501 ... . '1399 NEC 5510 Call for price

LANGUAGES

C BaSlC Your Cost $125

M Basic $325

Fortran $450

Cobol $650

Pascal (UCSD) Reg.$400. . . $325

EPROMReg $125 '120

Cuts access time in half. Allows serial number of machine on chio and all software.

DEALER INQUIRIES INVITED

TO ORDER CALL 1-800-426-2963

k INFORMATION CALL (206) 453-9777 or (509) 663-1626

»^7

NTERNATIDNAl

777 or (509) bbj-twb (Washington Residents Ado

5% Sales Tax)

(Division of Cornpotrr Marketing Corp.)

Administrative Offices ■ P.O. Box 679, Wenatchee, WA 98801 National and International Sales Office -11058 Main, Bellevue. WA 98004

such as Pascal. Brown is aware of this, and suggests more advanced readers look at David Gries's Compiler Construction for Digital Computers. If you plan to write more advanced compilers, it would be well worth your while to read Gries. However, if you are just starting out writing compilers, P J Brown's book is the one for you.

Language in Thought and Action (4th edition]

S I Hayakawa, Harcourt Brace Jovanovich New York, 1978 318 pages, softcover S8.95

Reviewed by Thomas Munnecke 6199 Shaker Drive Riverside CA 92506

At first glance you might wonder what this book by the flamboyant senator from California has to do with computers. Although it is ostensibly a textbook for students of semantics, it is actually a very timely and insightful guide for anyone interested in computer languages, systems design, program documentation, or software engineering.

Written in 1939, before the digital computer was even a dream, Language in Thought and Action offers valuable lessons for today's computer-smart reader. Forty-two years after publication, Hayakawa's book seems almost prophetic. Or perhaps our technology has not taken us as far as we would like to believe.

Hayakawa will appeal to anyone interested in logical thought processes and, more particularly, linguistics. He wrote "as a response to the dangers of propaganda, especially as exemplified in Adolf Hitler's success in per

306 February 1981 © BYTE Publications lnc

Circle 227 on inquiry card.

suading millions to share his maniacal and destructive views. It was my conviction then, as it remains now, that everyone needs to have a habitually critical attitude towards language—his own as well as that of others."

In order to fully appreciate his book, you must transfer the concept of "language" as the spoken word to the concept of "language" as it exists in the computing world. Both have syntax (how you say it), semantics (what you mean), and pragmatics (what you are trying to accomplish). Once you grasp the generality of language, you can understand the concept of computer language. Languages, specifications, and documentation suddenly appear in a new light.

Beginning programmers often seem unable to recognize the arbitrary nature of the symbols in the programming language. It is as if they see the term "SIN(X)" as some kind of magical incantation, rather than as a programmed abstraction of a particular language. Hayakawa's statement on this is as follows:

"We are, as human beings, uniquely free to manufacture and manipulate and assign values to our symbols as we please. Indeed, we can go further by making symbols that stand for symbols."

Although all computer languages manipulate and assign values to symbols, the early computer languages, such as FORTRAN, COBOL, and BASIC, restrict the dynamic manipulation of these symbols. Newer languages have gone further, creating symbols that stand for symbols, as in APL, PL/1, MUMPS, LISP, and Pascal.

For those initially confused by the apparent complexities of higher-level languages, Hayakawa offers this encouragement:

System Log

3-/o Am

Jg^fekjgjfej,

jQeUcw L

D/j&A/esr/cs *lt. v

£/XUd st£/z^u&<t a*w(.

Ajsf&fefH sfaicJ? or? ^ttt*^^

DIAGNOSTICS

Diagnostics II is SuperSoft's expanded Diagnostic package.

Diagnostic II builds upon the highly acclaimed Diagnostics I. It will test each of the five areas of your system:

Memory Terminal Printer CPU Disk

Every test is expanded.

Every test is "submit"-able. A "submit" file is included in the package which "chains" together the programs in Diagnostics II, achieving an effective acceptance test. All output can be directed to a log file for unattended operation, for example over night testing. Terminal test is now generalized for most crt terminals. A quick-test has been added for quick verification of the working of the system.

The memory test is the best one we have encountered. It has new features, including:

• default to the size of the CP/M Transient Program Area (TPA)

• printout of a graphic memory map • burn in test

• bank selection option • memory speed test Diagnostics-ll still includes the only CPU test for 8080/8085/Z80.

A Spinwriter/Diablo/Qume test has been added, which tests for the positioning and control features of the Spinwriter/Diablo/Qume as well as its ASCII printing features. (Serial Interface only)

And, as with all SuperSoft products, a complete online HELP system and user manual is included.

Price: $100.00 (manual only): $15.00

Requires: 32K CP/M

CP/M Formats: 8" soft sectored, 5" Northstar, 5" Micropolis Mod II, Vector MZ, Superbrain DD/QD

All Orders and General Information:

SUPERSOFT ASSOCIATES

P.O. BOX 1628

CHAMPAIGN, IL 61820

(217) 359-2112

Technical Hot Line: (217) 359-2691

(answered only when technician is available)

CP/M REGISTERED TRADEMARK DIGTAL RESEARCH

SuperSoft

First in Software Technology

February 1981 © BYTE Publications ]nc 307

ENTREPRENEURS

|m|^"^"| IB"I | MORE THAN EVER IN THE MICRO|f^m ^mUj COMPUTER INDUSTRY.

The shortage of knowledgeable dealers/distributors is the #1 problem of microcomputer manufacturers. Over 300 new systems houses will go into business this year, but the number falls short of the 1200 needed. It is estimated that the nationwide shortage of consultants will be over 3000 by 1981. The HOW TO manuals by Essex Publishing are your best guide to start participating in the continued microcomputer boom.

$36.

HOW TO START YOUR OWN SYSTEMS HOUSE

6th edition, March 1980

Written by the founder of a successful systems house, this

fact-filled 220-page manual covers virtually all aspects of

starting and operating a small systems company. It is abundant

with useful, real-life samples: contracts, proposals, agreements

and a complete business plan are included in full, and may be

used immediately by the reader.

Proven, field-tested solutions to the many problems facing the

small systems house are presented.

From the contents:

• New Generation of Systems Houses • The SBC Marketplace

• Marketing Strategies • Vertical Markets & lAPs • Competitive Position/Plans of Major Vendors • Market Segment Selection & Evaluation • Selection of Equipment & Manufacturer • Make or Buy Decision • Becoming a Distributor • Getting Your Advertising Dollar's Worth • Your Salesmen: Where to Find Them • Product Pricing • The Selling Cycle • Handling the 12 Most Frequent Objections Raised by Prospects • Financing for the Customer • Leasing • Questions You Will Have to Answer Before the Prospect Buys • Producing the System •Installation, Acceptance. Collection • Documentation • Solutions to the

Service Problem • Protecting Your Product • Should You Start Now? • How to Write a Good Business Plan • Raising Capital

HOW TO BECOME A SUCCESSFUL

COMPUTER CONSULTANT

HOW TO BECOME A SUCCESSFUL COMPUTER CONSULTANT

by Leslie Nelson, 2nd revised edition, Jan 1981 Independent consultants are becoming a vitally important factor in the microcomputer field, filling the gap between the computer vendors and commercial/industrial users. The rewards of the consultant can be high: freedom, more satisfying work and doubled ortripled income. HOWTO BECOME A SUCCESSFUL COMPUTER CONSULTANT provides comprehensive background information and step-by-step directions for those interested to explore this lucrative field:

• Established consulting markets • How to get started • Itemized start-up costs • Are you qualified? • Beginning on a part-time basis • The Marketing Kit • Should you advertise? • Five marketing tips • Getting free publicity • How much to charge

• When do you need a contract? • Sample proposals • Which J28. No. 16 jobs should be declined • Future markets • The way to real big

money • Avoiding the legal pitfalls • How consultants' associations can help you • The National Register of Computer Consultants • How others did it: real-life sample cases • and much more.

FREE-LANCE SOFTWARE MARKETING 3rd edition, June 1980 Writing and selling computer programs as an independent is a business where • you can get started quickly, with little capital investment • you can do it full time or part time • the potential profits are almost limitless. Since the demand for computer software of all kinds is growing at an explosive rate, the conditions for the small entrepreneur are outstanding.

This manual will show you how to sell your own computer programs using these proven techniques: • direct to industries • through consulting firms • through manufacturers of computer hardware • in book form • mail order • through computer stores. It will show you how to profitably sell and license all types of software ranging from sophisticated analytical programs selling forthousands of dollars, down to simple accounting routines and games for personal computers.

The book will guide you step by step through the process of $30. No. 32 marketing, advertising, negotiating a contract, installing software,

training users and providing maintenance and support. It also contains sample software contracts that have been used in actual software transactions. Also included are tips on how to negotiate with a large corporation, ways of avoiding personal liability, techniques for obtaining free computer time and hints on how to run a free-lance software business while holding a full-time job.

Name

Address City

.State.

-Zip

ESSEX PUBLISHING CO. Dept. 2

285 Bloomfield Avenue • Caldwell, N.J. 07006

Order books by number. Send check, money order (U.S.S), VISA or Master Charge #. Publisher pays 4th

class shipping. For UPS shipping (USA only)add $1.00 per book. For Air Mail shipping add $250 per book

in North America, $5.00 in Europe and South America. $8.00 elsewhere. N.J. residents add 5% sales tax

D No. 10 □ No. 16 □ No. 32 O Check enclosed O Credit card □ 4th class □ UPS □ Air

Card** Exp.

For faster shipment on credit card orders call (201) 783-6940 between 9 and 5 Eastern time.

"The fact that more things can go wrong with motorcars than with wheelbarrows is no reason for going back to wheelbarrows. Similarly, the fact that the symbolic process makes complicated follies possible is no reason for wanting to return to a cat-and-dog existence. A better solution is to understand the symbolic process, so that instead of being its victims, we become, to some degree at least, its masters."

He also warns that symbols must be viewed in their relationship to other symbols. I once had an experience with a computer programmed to assist in medical diagnoses. I was asked to type in my symptoms, and the computer would respond with a possible diagnosis. Being on the last leg of a hectic cross-country trip, I selected symptoms of headache, tiredness, and so forth. The computer responded with the suggestion that I was suffering from pre-menstrual tension. It unfortunately ignored the critical context that I was male.

The chapter on "Reports, Inferences, and Judgments" directly corresponds to the chronological development of the computer technology industry. The "report" concept is equivalent to the old batch-run systems in which the entire file is reported to the user after each batch is run. Many of these systems are being reprogrammed to run on-line with the manipulation of only selected data—in correspondence to Hayakawa's "inference." And finally, the "judgment" concept applies to the use of the computer in the future, as it becomes actively involved in making its own decisions in such disciplines as artificial intelligence or modeling.

Hayakawa then turns to a discussion about standards. He cites the chaos existing in the time zone standards before the year 1883:

308 Febnjary 1981 © B YTE Publications Inc

Circle 229 on inquiry card.

"When it was noon in Chicago, it was 12:31 in Pittsburgh, 12:24 in Cleveland,

12:17 in Toledo There

were twenty-seven time zones in Michigan alone. (When the time zones were standardized, farmers were afraid of the change, saying that their cows would not know when to come home.)"

The comparison with computer language standards is clear. How many BASIC and Pascal dialects and extensions are there? And how many interpretations of the S-100 bus are floating around? When it comes to getting modernday language implementors to agree on a standard version, one meets just as many sacred cows.

His section "Presymbolic Language in Ritual" could just as well have been discussing the ritualistic statements forced upon the COBOL programmer every time he writes a program. A strong comparison could be made between this meaningless process in COBOL and the multitude of religions around the world which conduct services in old and forgotten languages.

In "How We Know What We Know," Hayakawa explains the process of abstracting. He takes us from a quote by Ambrose Bierce:

"An edible: Good to eat and wholesome to digest, as a worm to a toad, a toad to a snake, a snake to a pig, a pig to a man, and a man to a worm "

to an exposition of the levels of abstraction of a cow, in an essay that should be required reading for all programmers who strive for structured programming or structured design.

The section "On Definitions" should be read by anyone who is too impressed by program documentation outside the program:

CALL TOLL FREE

800-538-5000

CALL US FOR VOLUME QUOTES WE WILL BEAT ANY COMPETITORS PRICES. GIVE US A CALL AND WE'LL PROVE IT

NEC UPD416C-2 4116-200NS

8/29.95 100/3.45ea

2716-SINGLE SUPPLY

10.95EA 8/9.95EA

2708 6.25ea 8/5.95ea

2114L-3 4K STATIC

LOW POWER 300 NS 8/29.95 100/3.49ea

, a ■ *». a. Low Power , _ -^

21L02 «°NS 1.29ea

2102

450NS

.99e/

LS SERIES

LOOK AT THIS LS PRICING!

74LS00 74LS01 74LS02 74LS03 74LS04 74LS05 74LS08 74LS09 74LS10 74LS11 74LS12 74LS13 74LS14 74LS15 74LS20 74LS21 74LS22 74LS26 74LS27 74LS28 74LS30 74LS32 74LS33 74LS37 74LS38 74LS40 74LS42 74LS47 74LS48 74LS51 74LS54 74LS55

.32 74LS73

.28 74LS74

.38 74LS75

.32 74LS76

.35 74LS78

.28 74LS83

.38 74LS85

.38 74LS86

.32 74LS90

.29 74LS92

.29 74LS93

.38 74LS95

.99 74LS96

.35 74LS107

.26 74LS109

.30 74LS112

.34 74LS113

.40 74LS114

.35 74LS122

.39 74LS123

.35 74LS125

.39 74LS126 74LS132

.78 74LS136

.39 74LS138

.25 74LS139

.79 74LS145

.78 74LS148

.78 74LS151

.35 74LS153

.35 74LS154

.32 74LS155

8080 SUPPORT

8212 8214 8216 8224 8226 8228 8238 8251 8253 8255 8257 8259 8275 8279

2.75

5.25

2.75

2.95

3.49

4.95

5.50

6.95

12.95

6.50

16.95

14.95

4995

15.95

MISC

Ay5-10l3

8T97

1488

1489

8202

3242

4.99 1.69 1.39 1.39 34.95 16.95

74LS156 74LS157 74LS158 74LS160 74LS161 74LS162 74LS163 74LS164 74LS165 74LS166 74LS168 74LS169 74LS170 74LS173 74LS174 74LS175 74LS181 74LS190 74LS191 74LS192 74LS193 74LS194 74LS195 74LS196 74LS197 74LS221 74LS240 74LS241 74LS242 74LS243 74LS244 74LS245

MM5203AQ

MM5204AQ

1702A

2708

2716

2732

74LS251 74LS253 74LS257 74LS258 74LS259 74LS260 74LS266 74LS273 74LS275 74LS279 74LS283 74LS290 74LS293 74LS295 74LS298 74LS352 74LS353 74LS363 74LS365 74LS366 74LS367 74LS368 74LS373 74LS374 74LS377 74LS385 74LS386 74LS390 74LS393 74LS395 74LS670

EPROMS

1us 750ns

lus 450ns 450ns 450ns

256x8 512x8 256x8 1Kx8 2Kx8 4Kx8

13.95 14.95 4.95 5.95 10.95 29.95

PROMS

CPU'S

74S188 74S287 74S288 74S387 74S471 74S472 74S474 74S570 74S571

(82S23) (82S129) (B2S123) (82S126)

(82S147) (82S141) (62S130) (82S131)

32x8 256x4

32x8 256x4 256x8 512x8 512x8 512x4 512x4

4.75

4.75

4.75

5.75

18.75

18.75

19.95

7.80

7.80

Z-80

Z-80A

8080A

8085A

2650

9.95 12.95

3.95 12.95 12.95

|.43"LED DESPLAY

BEAUTIFUL RED

|7SEGMENT DISPLAY

HP 4082-7760

.79 100/.65ea

DIP

SWITCHES

LINEAR

4 Position .99

7 Position 1.09

LM30IV .34 LM567V1.29

' 5 Position 1.02

8 Position 1.14

LM309K1.49 LM723 .49

6 Position 1.06

LM311V .64 LM741V .29

LM317T2.29 LM747 .79

■ VOLTAGE REG'S

IC SOCKETS

LM323K4.95 LM1310 1.90

I 7805T .89 7905T

.99

8 PIN 10/1.29

LM324 .59 LM1414 1.59

■ 7812T .89 7912T

.99

LM339 .99 LM1458 .69

1 7815T .99 7915T

1.19

16 PIN 10/1.69

LM377 2.29 LM1488 1.39

I 7824T .99 7924T

1.19

18 PIN 10/1 99

LM380 1.29 LM1489 1.39

1 7805K 1.39 7905K

1.49

20 PIN 10/2.89

LM555V .39 LM1800 1.99

1 7812K 1.39 7912K

1.49

22 PIN 10/2.99

LM556 .69 LM1889 2.49

1 78L05 .69 79L05

.79

24 PIN 10/2 99

LM565 .99 LM3900 .59

■ 78L12 .69 79L12

.79

28 PIN 10/3.99

LM566V1.49 75451V .39

> 78L15 .69 79L15

.79

40 PIN 10/4.99

VISA'

1101 South Winchester Blvd. San lose, California 95128 408-247-4852 800-538-5000

TERMS: Include $2.00 for shipping.

complete catalog. Bay Area Residents add 6Vi% sales tax Calif. Residents add 6%sales tax. We reserve the right to limit quantities and substitute manufacturer.

Circle 230 on inquiry card.

February 1981 © BYTE Publications Inc 309

Circle 231 on Inquiry card.

PRINTER SPECIALS

FOR ALL POPULAR MICROCOMPUTERS

CENTRONICS 737*-$795

• 80-50 CPS — back/forward feed

• 18 X 9 dot matrix — U/L case

• Proportional, expanded compressed

• 3 way paper feed

Parallel interface card & cable for Apple II. . $175

PSON MX-80-- $645

• 80 CPS — bidirectional

• 9 X 9 dot matrix — U/L case

• Compressed & expanded print

• Adjust tractors arallel interface & cable for

Apple II. . . .5110

COMPUTERWARE"

1512 Encinitas Blvd. • Box 668 Encinitas. CA 92024 • (714) 436-3512

HOWTOORDER

Phone orders are invited. Use VISA. MasterCharge, or send cashiers check or noney order drawn on a U.S. bank. Add 2% shipping and handling or primer will De sent freight COD.

Write for our Special Mail-Order Prices

cippkz computer

* Authorized Dealer

t

TO^Me memory for your disk

TWICE THE BYTE

WITH OUR $25.95 KIT

INSTANTLY DOUBLES DISK CAPACITY

Kit includes special tool and instructions for use with 5V2" and 8" floppies.

Call collect to order: 1-305-942-4013

ADAPTIVE SYSTEMS, INC.

904 S. W. 2nd Place

Pompano Beach, Florida 33060

TO ORDER TWICE THE BYTE KIT:

Please phone using VISA or Master Card Or send cashier's check, money order or personal check (allow 14 business days to clear ).

'Kit $25.95 plus $2.00 postage and handling. Florida residents add 4% sales tax.

Total enclosed: $

D Personal Check D Money order or Cashier's check

D VISA D MASTER CHARGE (Bank No

Acct. NO. Exp. Date

Signature

Print Name

Address

City

State Zip

J

"Definitions, contrary to popular opinion, tell us

nothing about things That

is, when we stay at the same level of abstraction in giving a definition, we do not give any information, unless, of course, the reader is already sufficiently familiar with the defining words to work himself down the abstraction ladder."

The concept of "DeadLevel Abstracting" describes the person who is permanently stuck at a certain level on the abstraction ladder. Hayakawa defines the two extremes—the low-level, who "go on indefinitely, reciting insignificant facts, never able to pull them together..." and the highlevel, whose language "remains permanently in the clouds." These extremes describe two personalities often found in computerrelated environments. The low-level personality is typified by a COBOL programmer, determined never to learn another language because he already "knows how to program." The highlevel person is apt to be a systems analyst who dreams of computing the world. These two approaches to systems design could be called "bottom down" and "top up," respectively.

The sections "Confusion of Levels of Abstraction," "Classification," "The Blocked Mind," and "Cow, is not Cow2" will capture the sympathy of anyone who has grappled with the problems of systems design. "The Two-Valued Orientation" could have been written by someone criticizing the computer's ruthless binary decision-making process.

Today, "Poetry and Advertising" could easily be renamed "Poetry and Programming." Hayakawa's phrase, "Advertising is a symbol-manipulating occupation," is reminiscent of Frederick Brooks's approach in his excellent book about

computer programming, The Mythical Man-Month:

"The programmer, like the poet, works only slightly removed from pure thoughtstuff. He builds castles in the air, from air, creating by the exertion of the imagination. Few media of creation are so easy to polish and rework, so readily capable of realizing grand conceptual structures."

This analogy might help explain the programmer's personality to outsiders.

Perhaps the most meaningful summary of the book is Hayakawa's own. In his section "Rules for Extensional Orientation," he writes:

" 1. A map is NOT the territory it stands for; words are NOT things.

2. The meanings of words are not in the words; they are in us.

3. Contexts determine meaning.

4. When tempted to 'fight fire with fire' remember that the fire department usually uses water.

5. The two-valued orientation is the starter, not the steering apparatus.

6. Beware of definitions, which are merely words about words."

All in all, this is an insightful book on language in action. ■

BYTE's Bits

Punk Rock Discovers Tl's Speak & Spell

Adam and the Ants, a California-based punk-rock group, is churning out hit records featuring Texas Instruments' Speak & Spell speech-synthesis toy. In one song, Speech & Spell chants out the word "echo" over the background tones of a guitar and music synthesizer. ■

310 February 1981 © BYTE Publications Inc

Circle 232 on inquiry card.

Circle 233 on inquiry card.

EXCLUSIVE

Capacity that used to cost thousands more.

DAS ANALOG I/O SYSTEM

• For use with your APPLE

• Scientiiic Quality A/D — D/A Conversion

• 12-Bit Precision

• Fully Family ol Modules tor Conditioning Conversion & Control

• Modular, Expandable

• Programmable Gain Amplilier

• READY TO GO.

Standard System Sl.SOO.

800-343-5504

-, SYSTEMS

ICOMPUMART

SINGLE * BOARD TECHNOLOGY

tf^sSW

Basic system with: 600K bytes

$2425.

1.2 megabytes $2990. 2.4 megabytes $3550.

A Z80A CPU combined with the CP/M® operating system opens new vistas to software availability for eight-bit micros. FORTRAN, COBOL, BASIC, APL, PL/1 and

Pascal are available now to accommodate today's

scientific, educational, sophisticated small business

and personal system users.

4MHz Z80A CPU CP/M 2 operating system 64K 200ns main memory 6K 300ns video memory 8-inch dual floppy drives

colorvideotext& graphics sound generator 2-serial ports 2-parallel ports 4-counter/timers

Dealer discounts are available. OEM inquiries are invited. Please contact:

COLONIAL DATA SERVICES CORP.

05SanfordSt.,Hamden,Connecticut06514 (203)288-2524

®CP/M is a registered trademark ot Digital Research. Inc.

ATARI

* PERSONAL COMPUTER SYSTEM

OWNERS!

INSTANT 32K RAM BOOST: $320

Our new RAMCRAM gives you 32,768 bytes of add-in RAM, ready to go, for less than a penny a byte. Send the money or call (408) 727-0863 and you can bill it to your bank card. Allow 3-6 weeks for delivery, please. Also available at your local computer store.

For the ATARI 400*:

There is a RAM slot inside your system. We designed RAMCRAM to fit it. Installation is simple, and must be performed by qualified personnel. It isplug-in compatible, of course, and allows the ATARI 400 to accept all software for 32K machines.

For the ATARI 800*:

Your system has three RAM slots in the card cage. Used with one ATARI 16K RAM module, RAMCRAM adds all the memory you can now use (48K bytes), leaving a third slot available for further expansion.

170 Wolfe Road

Sunnyvale, CA 94086

(408) 727-0863

AXLON

^Indicates trademarks of Atari, Inc.

Circle 279 on inquiry card.

BYTE February 1981 311

A/D and D/A ConversionAn Inexpensive Approach

Roger W Mikel

5504 Thomas Ln

Ft Worth TX 76114

Although there are many ways to achieve the conversion of data from analog to digital form, a converter that is simple, fast, inexpensive, and reasonably accurate is seldom available to the serious experimenter. Here I will describe a design that fulfills these characteristics.

To be of practical use, a converter should have at least 8 bits of resolution and be accurate to 0.4% (the value of the least significant bit). In most cases, the conversion should be complete in 10 to 20 /ts; this is about as fast as most microprocessors can collect two measurements and do anything with them.

Theory

After ruling out V/F (voltage-tofrequency conversion), slope integration, and charge-balancing systems because of their slowness or complexity, I finally decided that the circuit should consist of a counter cycling continuously to drive a D/A (digitalto-analog) resistance ladder, commonly called an R/2R circuit. The ramp signal produced is used as a reference voltage which the analog input signal is compared with.

The output of a comparator may be used to strobe latches that sample the output of the counter. This means

that a conversion is completed every 256 clock cycles—at 20 MHz, the conversion takes less than 13 /is.

The Circuit

The clock circuit is based on a K1100A packaged oscillator produced by Motorola, designated as

This converter is simple, fast, inexpensive, and reasonably accurate.

ICl in figure 1. This particular circuit was chosen primarily because one was on hand. There are a number of other circuits that would work as well, such as a 74123 multivibrator connected in an astable configuration, or an NE555 timer (if speed is not a consideration). For full-speed operation, the clock frequency can be in the range of 20 MHz and should have a clean square-wave output to drive the counter stage properly.

The counter stage consists of IC2 and IC3, both 74193 synchronous 4-bit up/down counters. These are

designed to switch simultaneously and therefore do not produce the switching transients seen at the outputs of asynchronous ripple counters. Such "glitches" would result in erratic comparator operation.

A second advantage of these devices is that they may be loaded in parallel; this allows us to use the circuit in converting data both to and from digital form. The parallel output from these counters drives the 74173 quad-D latches (IC4 and IC5) as well as the resistance ladder.

The resistance ladder is a network of resistors designed to produce a voltage proportional to the binary number applied. The output voltage that appears at point A in figure 1 is described by equation 1. E0 thru E7 represent the voltages present on the eight counter-output lines. Since the counter output is nominally 5 V, voltages from 20 mV to almost 5 V can be generated in 20 mV increments.

The actual value of R in figure 1 is not too important, and can be anywhere in the range of 5000 to 50,000 ohms. It is important that all resistances in the ladder are closely matched because this will affect the accuracy of the circuit. A good method to ensure close tolerance is to

312 February 1981 © BYTE Publications Inc

Circle 234 on inquiry card.

BUSINESS SOfTWflR€ FORTHCZ-89!

S Si M Systems, Inc., the "All-in-One" Software Company

is offering a full line of Business Packages for the

"flll-ln-One" Z-89 Microcomputer

lnseq-80(TM) Business Software Systems Industry Standard Osborne Based: Accounts Payable/Receivable,

General Ledger, Payroll

S & M Software: Retail Inventory Control, Invoicing, Manufacturers Inventory Control, Customer Mail List

PLUS MANY MORE!!

All Systems have been Field Tested and are ready for shipment!

CALL ABOUT OUR NATIONAL DEALER PROGRAM AND JOIN THE BEST

IN SELLING THE FINEST SOFTWARE ON THE Z-80 MARKET!

SYSTEMS ALSO OPERATE ON TRS-80 MOD I, MOD II. MOD III AND ALTOS MICROCOMPUTERS

For Further Information, Contact: S & M. Systems, Inc. Or Dial Direct: 1-617-373-1599

P.O. Box 1225 1-617-481-5231

Haverhill, Massachusetts 01830

SOFTWARE FOR THE ATARI 800*

QS FORTH'" by James Albanese. Step into the world of the remarkable FORTH programming language. Writing programs in FORTH is much easier than writing them in assembly language, yet FORTH programs run almost as last as machine code and many times faster than BASIC programs. QS FORTH is based on fig-FORTH, the popular model from the FORTH Interest Group that has become a standard for microcomputers. QS FORTH is a disk-based system that can be used with up to four disk drives. There are five modules included:

1. The FORTH KERNEL (The standard fig-forth model customized to run on the Atari computer).

2. An EXTENSION to the standard vocabulary that contains some handy additional words.

3. An EDITOR that allows editing source programs (screens) using Atari type editing.

4. An 10 module that makes I/O operations easy to set up.

5. An ASSEMBLER that allows defining FORTH words as a series of 6502 assembly language instructions.

Modules 2-5 may not have to be loaded with the user's application program, allowing for some efficiencies in program overhead. Full error statements (not just numerical codes) are printed out, including most disk error statements. QS FORTH requires at least 24K of RAM and at least one disk drive. For the Atari 800 only. On diskette only - $79.95

TARI TREK" by Fa bio Ehrengruber. Get ready for an exciting trek through space. Your mission is to rid the galaxy of Klingon warships, and to accomplish this you must use strategy to guide the starship Enterprise around stars, through space storms, and amidst enemy fire. Sound and color enliven this action packed version of the traditional trek game. Nine levels of play. At the higher levels you play against elapsed time. Written in BASIC. Requires 24K on cassette and 32K on diskette. Cassette - $11.95

Diskette-$14.95 FASTG AMMON'" by Bob Christiansen. Play backgammon against a talented computer opponent that plays very fast, usually deciding on its move in less than a second. Roll your own dice or let the computer roll them for you. Adjust the display speed to your liking. FASTGAMMON is a good way to learn the game and a good way to improve your skill. A special replay feature lets you play a game over using the same dice rolls. Written in machine language and requires only 8K of RAM so that it can run on theAtari400* as well as the Atari 800. On cassette only - $19.95

TANK TRAP by Don Ursem. A rampaging tank tries to run you down. You are a combat engineer, building concrete barriers in an effort to contain the tank. Use either the keyboard or an Atari joystick to move your man and build walls. Trap the tank and receive a rank based on your performance. Four levels of play, music, color, and sound effects add to the excitement of this game, which can be played and is enjoyed by people of all ages. Written in BASIC with machine language subroutines. Requires at least 16K of user memory on cassette and 32K on diskette. Cassette - $11.95

Diskette - $14.95

ASSEMBLER by Gary Shannon. Write your own 6502 machine language programs with this inexpensive in-RAM editor/assembler. Use the editor to create and edit your assembler source code. Then use the assembler to translate the sourcecode into machine language instructions and store the code in memory.Simplecommandsallowyoutosave and load the source code to and from cassette tape. You can also save any part of memory on tape and load it back into RAM at the same or at a different location. The assembler handles all 6502 mnemonics plus 12 pseudo-ops that include video and printer control. A very useful feature allows you to view and modify hexadecimal code anywhere in memory. Instructions on how to interface machine language subroutines to your BASIC programs are included. Requires 16K of user memory and runs on both the Atari 800 and the Atari 400*. On cassette only • $24.95

6502 DISASSEMBLER by Bob Pierce. This neat 8K BASIC program allows you to disassemble machine code, translating it and listing it in assembly language format on the video and on a printer if you have one. 6502 DISASSEMBLER can be used to disassemble the operating system ROM, the BASIC cartridge, and machine language programs located anywhere in RAM except where the DISASSEMBLER itself resides. Also works as an ASCII interpreter, translating machine code into ASCII characters. 6502 DISASSEMBLER requires only 8K of user memory and runs on both the Atari 800 and the Atari 400. Diskette version requires 24K. Cassette - $11.95

Diskette - $14.95

QUTILrTY SOFTW7IR€

6660 Reseda Blvd., Suite 105, Reseda. CA 91335

(213)344-6599

"Indicates trademarks of Alan, Inc.

WHERE TO GET IT: Call us at (213) 344-6599 forthenameof the Quality Software dealer nearest you. If necessary you may order directly from us. MasterCard and Visa cardholders may place orders by telephone. Or mail your check or bankcard number lo Quality Software, 6660 Reseda Blvd., Suite 105, Reseda, CA 91335. California residents add 6% salestax. SHIPPING CHARGES: Within North America orders must include $1.50 for first class shipping and handling. Outside North America the charge for airmail shipping and handling is $5.00. Pay in U.S. currency.

Circle 235 on inquiry card.

BYTE February 1981 313

8-BIT D5 D4

/*

^

JF

Q4 Q3 Q2 Ql G2 Gl

D4 D3 DZ Dl

IC5 74173

N M

CK

CLR

ANALOG |—. INPUT I—->_

5K

attenuator;:

11

12

13

IK

_vw

l/O PORT

D3 D2 Dl DO

i

CK

Q4 Q3 Q2 Ql

IC4 74173 CLR D4 D3 D2

11

12

13

rn

DD DC DB DA

74193 uu

CLR OC QB OA

LM311

m

ANALOG OUTPUT (MUST BE -SO

BUFFERED )

Figure 1: This schematic diagram shows that a small number of parts (all easily obtainable) can be used for a fast, flexible converter. Operation is switch-selectable for A/D or D/A modes; conversion takes less than 13 /ts in A/D mode, and is almost instantaneous in D/A mode. Speed of conversion is set by clock frequency and propagation delays in the integrated circuits used. The concept is easily expandable to 12 or 16 bits, if necessary.

Equation 1

Output

Voltage =

E7 + E6 + E5 + E4

+ E3 + E2 +

El

+

EO

2

4

8

16

32

64

128

256

buy twenty-five resistors of the same value from the same batch, then use two resistors in series for each 2R leg. In the D/A conversion mode, the output, which may be taken from point A, must be buffered, since the counter outputs are of the low-power type.

The voltage comparator (IC7) compares the analog input signal to the output voltage of the resistance ladder. Since the counter increments from zero, the ladder output should start out lower than the analog signal. When the ladder output level is

greater than the analog signal, the comparator senses the change and provides a strobe to latch the counter values into IC4 and IC5. A 5 k-ohm potentiometer may be included to attenuate input signals greater than 5 V.

The comparator is an LM311, which was chosen because it requires only a single-ended power supply. This simplifies construction considerably.

The output latches (IC4 and IC5) are a pair of 74123 quad-D flip-flops. They were chosen because of their low drive requirements and their

1

DD DC DB

CARRY

IC2

74193

CLR

QD QC QB QA

IC1 K1100A

Number

Type

+ 5V

GND

IC1

K1100A

1

2

IC2

74193

16

8

IC3

74193

16

8

IC4

74173

16

8

IC5

74173

16

8

IC6

7404

14

7

IC7

LM311

8

1,4

three-state outputs. The output pins may be connected to the parallel inputs of the counter circuit, and their three-state ability allows the use of one port for both input D/A and output A/D (analog-to-digital) operation.

Operation

A complete A/D conversion cycle goes as follows (refer to figure 2):

The cycle starts as the counter goes through hexadecimal 00. The voltage at point A is at zero and the output latch contains the result of the last conversion cycle.

The counter increments toward hexadecimal FF, and at some

314 Februaiy 1981 © BYTE Publications Inc

32 K BYTE MEMORY

RELIABLE AND COST EFFECTIVE RAM FOR 6502 6 6800 BASED MICROCOMPUTERS

AIM 65-*KIM*SYM

PETS44-BUS

. PLUG COMPATIBLE WITH THE AIM-65/SYM EXPANSION CONNECTOR 'BY USING A RIGHT ANGLE CONNECTOR (SUPPLIED) MOUNTED ON THE BACK OF THE MEMORY BOARD.

• MEMORY BOARD EDGE CONNECTOR PLUGS INTO THE 6800 S 44 BUS.

• CONNECTS TO PET OR KIM USING AN ADAPTOR CABLE. . RELIABLE-DYNAMIC RAM WITH ON BOARD INVISIBLE

REFRESH-LOOKS LIKE STATIC MEMORY BUT AT LOWER COST AND A FRACTION OF THE POWER REQUIRED FOR STATIC BOARDS.

• USES -5V ONLY. SUPPLIED FROM HOST COMPUTER.

• FULL DOCUMENTATION. ASSEMBLED AND TESTED BOARDS ARE GUARANTEED FOR ONE YEAR AND PURCHASE PRICE IS FULLY REFUNDABLE IF BOARD IS RETURNED UNDAMAGED WITHIN 14 DAYS.

ASSEMBLED WITH 32K RAM $395 00

8 WITH 16K RAM $339.00

TESTED WITHOUT RAM CHIPS $279.00

HARD TO GET PARTS (NO RAM CHIPS)

WITH BOARD AND MANUAL $109.00

BARE BOARD & MANUAL S49.00

PET INTERFACE KIT-CONNECTS THE 32K RAM BOARDTO A 4K OR 8K PET. CONTAINS: INTERFACE CABLE. BOARD STANDOFFS, POWER SUPPLY MODIFICATION KIT AND COMPLETE INSTRUCTIONS $49.00

U.S. PRICES ONLY

i.^a^iT^iiJij-L iiy - "a32sr-: •

ii*S=4i(K^^^^^

Circle 236 on Inquiry card.

16K MEMORY EXPANSION KIT

ONLY

$58

FOR APPLE, TRS-BO KEYBOARD, EXIDY, AND ALL OTHER 1BK DYNAMIC SYSTEMS USING MK4116-3 OR EQUIVALENT DEVICES.

• 200 NSEC ACCESS, 375 NSEC CYCLE

• BURNED-IN AND FULLY TESTED

• 1 YR. PARTS REPLACEMENT GUARANTEE

• QTY. DISCOUNTS AVAILABLE

ALL ASSEMBLED BOARDS AND MEMORY CHIPS CARRY A FULL ONE YEAR REPLACEMENT WARRANTY

COmPUTER DEVICES

1230 W.COUinS AVE.

ORflDGE, Cfl 92668

(714)633-7280

oppk II phi/

With 48Kof memory!

$1042°°

With thepurchase of

the APPLE II /

select from the helow SPECIAL PRICING

/ Base2 tlnntei 5599' Disktl*»/conl....5B5'

Diskll 475'

Ser.PnnteiCd... 179'

SupFfMod 23°°

3way l/OSelect.. 33°° Video 100 12"... "9" FtrmWilreCard 149°° UHFIoRCAC.ible 5°°

74LS00

74LS02

74LS03

74LS04

74LS06

74LS09

70LS10

74LS20

74LS21

74LS22

74LS26

74LS27

74LS30

74LS32

74LS3B

74LS42

74LS48

74LS51

74LS54

74LS74

74LS75

74LS83

74LS85

74LSB6

74LS90

74LS93

74LS107

74LS112

74LS113

74LS122

74LS123

74LS126

74LS136

74LS151

74LS153

ll/appkllplu/

With60Kof memory!

$1259°°

■ Switch from "APPLESOFT"to

"INTEGER BASIC"and back again.

■ With DiscOperating System DOS 3.3 run PASCAL program withoutneedfora PASCAL card.

COLOR

Ow^/monitor 13

26

74LS155

115

26

74LS158

75

26

74LS160

95

76

74LS161

R6

?R

74LS162

95

26

74LS163

160

26

74LS164

66

26

74LS165

66

28

74LS170

1 75

26

74LS174

75

49

74LS175

76

26

74LS190

75

,?fl

74LS193

96

.1?

74LS195

96

3?

74LS196

a5

65

74LS221

140

78

74LS240

165

25

74LS241

165

35

74LS243

146

.TB

74LS244

145

60

74LS245

2 25

44

74LS253

95

95

74LS257

96

95

74LS258

95

69

74LS259

?R5

69

74LS279

44

45

74LS2B3

ino

38

74LS293

1R6

48

74LS298

120

4«

74LS366

96

95

74LS367

56

69

74LS36B

55

69

74LS373

1.39

44

74LS374

139

44

74LS386

65

EPROMS 2708 IkxB 5.95 8 FOR 40.00 2716 2k x 8 9.95 single ps 8 FOR 80.00 2732 4k x 8 24.95 2716 2k x 8 6.95 triple ps

APPLE EXPANSION Kll| 16K MemoryAddOn

appk dodt/cakndai

s12495

,hotirs,day(*v**?k

On board batteries with one year life.

Uses MSM5B32-crystal controlled.

California Computer Sntems

MISCELLANEOUS

8038C

NE555V

7905 .

7908 '•-.

7915

7918

7805

7806

7808 .

7812

MC1330AIP

MC1350P

MC1358P

LM380N

NE565N

MC1458P

IS410 sen

IT410 TP.IAC

s

'17" p^

LOGIC

KOBE

KIT

BUY FIVE OR MORE FOR

.516.95 each

WE CARRY

1.60 1.15 1.50 1.75 1 25 .50 .95 .95

COflCORD

COfflPUTCR

components

APPIE inTCRPOCE CARD!

CtnTTtOftfCiPflHmR j i»

KXTWnuflKflTIOm <"/cwwi.Icobk 9W BUM II comnouin <t.».fc u iw

lOTKC * BMK PUtmUMM 193

RPPUfOfT P1MTM1MU W

pflicmutoGuecE packags w»

PfMMICI PMflTER ITS

PROTOTWOG/HOWV M

HIHM RKNM IM

s/oo

/tit staticMIMMYIt *2*t

32K static memttr n. *ft

i*X tTHAMICMOMtYia. S3 J

*ti*tx*ms n Mr np

tn emir lit

MAItfMAAW/Kt MM. 37f

BISK CMTMtUf* H. J«

SWITCHES

2114 200ns 2114L 30Ons 2114L 20Ons 4116 300ns 4116 200ns

350 3.75 4.25 4.95 5.45

1971 SOUTH STATE COLLEGE

ANAHEIM, CALIF. 92806

VISA MASTERCHARGE MINIMUM ORDER •10.00

CHECK OR MO. ^W- ,*\^v-«--»-*-*_ ADD«1.50F0RFRT.0N

no cod r 714j937'0637 orders under »so.

SN7400N SN7402N SN7404N SN7408N SN7410N SN7412N SN7413N SN7414N SN7416N SN7417N SN7423N SN7425N SN7430N SN7437N SN7438N

.20 SN7440N .22 SN7442N .22 SN7443N .24 SN7445N .22 SN7451N .28 SN7454N .35 SN7474N 49 SN7475N 29 SN7482N .29 SN7492N .28 SN7493N .25 SN7495N .23 SN7496N 29 SN74122N 24 SN74136N

22 SN74141N

.57 SN74151N

78 SN74153N

.78 SN74154N

20 SN74155N

20 SN74157N

32 SN74160N

.32 SN74161N

1.05 SN74163N

.50 SN74164N

.48 SN74165N

.60 SN74174N

.70 SN74175N

.39 SN741BON

.95 SN74181N

.69 .65 .65 1.25

80 .69 95 65 85 .87 .87 .95 69 .75 1.15

MSM5832

:essor #45

REAL-TIME CLOCK

TRS80 '4395

KIT CONTAINS DIP SWITCHES ANDDETAILEO INSTRUCTIONS

No"Glitches", Surges Or Interference

THE MP0TT7 TURNS * ORDINARY OUTLET II ~ A CONTROLLED FILTE POWER SOURCE FOP. UP TO EIGHT DEVICES

Circle 237 on inquiry card.

BYTE February 1981 315

ANALOG INPUT POINT A

COMPARATOR OUT DATA OUT

COUNTER BITS 0-7 f

Figure 2: This timing diagram shows that, when the reference voltage (point A) has reached the level of the analog-input signal, the comparator toggles to strobe the 74173 latches. Data in the latches remains valid until the comparator toggles again.

point the voltage at point A will be equal to the analog input voltage. At this time, the comparator will drive the clock input (pin 7) to the latches high. The rising edge of the pulse will cause the latches to retain the state of the counters at that time.

This data is retained until the next conversion is finished.

In the A/D mode, the data is applied to the counter inputs with the load pin (pin 11) grounded. This feeds the digital information directly to the resistance ladder, so conversion is immediate.

Construction

As long as component leads are kept short, no special construction practices are required. I believe that

wire-wrap is the best way to build such projects. Due to the high speed of the circuit, it is important to bypass each integrated circuit with a 0.1 (i? capacitor. I soldered the bypass capacitors directly to the back of the sockets. Any component failures in the bypass network will show up as erratic operation (due to noise).

Application

The A/D operation of the circuit is very simple. Connect the circuit to an 8-bit I/O (input/output) port; when you want a measurement, simply read the value that appears at the port. Operation is similar in the D/A mode; simply write data to the port (with the select switch set to D/A). The analog input signal may range from zero to about 4.5 V (or greater with the optional attenuator). Analog outputs have the same range, unless you take the trouble to install a buffer amplifier.

Of course, the concept is expandable; 12-bit and 16-bit converters are easily possible with a few more components, although conversion times will be longer. ■

THE FIRST TRS-80® COMPATIBLE COMPUTER WITH HIGH DENSITY COLOR GRAPHICS !

LNW80

LNW RESEARCH introduces the LNW80, a high performance color computer, compatible with the TPS-80™ Model I. The fully integrated LNW80 is a soph is ticnted and versatile microcomputer with the following powerful features.

COMPATIBILITY

Hardware and software compatible to the Radio Shack TRS-80™ flodel I compute r, provides the widest software base of any microcomputer, cassette intcrfacr*; sxpansion bus

DISPLAY

quality upper and lower case display.

Two modes of color graphics, high resolution graphics, 384 x 192 in eiynt colors - higher density than the Apple II'. Low density color yrapjiics of 128 x 192 are also available in eight colors.

iliijii resolution - black and white graphics - of 3 8A x 192 mixed with text and TRS-80™ standard graphics. Reverse video. composite video RF ou tpu t.

PERFORMANCE

The LNWHO utilizes the fast Z-80A microprocessor which executes at a speed of 4 MHZ - over twice the speed of the TRS-80™ Model I.

PC BOARD

$89.95

EXTERNAL DATA SEPERATOR

LNW RESEARCH

Ask about our : Keyboard

N

caDlnel U*d«x VIDCO 100-110

\

W

LNW RESEARCH 3163-E AIRWAY AVE COSTA MESA CA 92628 714-552-6948

ORDERING INFORMATION

CA raiidtnli addiXi.

SYSTEM EXPANSION

AT

££Q.M lpc BOARD * 1

vO.7 LusermanualJ

- SERIAL RS232C/20mA I/O

- FLOPPY CONTROLLER

• 32K BYTES MEMORY

• PARALLEL PRINTER PORT

- DUAL CASSETTE PORT

> REAL-TIME CLOCK

> SCREEN PRINTER BUS ONBOARD POWER SUPPLY SOFTWARE COMPATIBLE SOLOER MASK,SILK SCREEN

316 February 1981 © BYTE Publications Inc

Circle 238 on inquiry card.

Why Do Professionals Prefer

BECAUSE

• Unique software • Technical support • Quick delivery • Established company • Release 2 CP/M3 (some packages under UNIXJ and TRSOOS')

• Quality software • In-house expertise • Fast response • User orientation • Competitive prices

• Customer service • Verbatim6 media • Onyx hardware (CP/M and UNIX versions).

Business Medical Real Estate Computer Systems

BECAUSE

Unique swift routing Cybernetics response system gives you no-nonsense technical answers that save you time. Call: (714) 848-1922.

• NEW RM/COBOL1 applications:

• Order Entry/Inventory • Receivables • Payables • General Ledger • Financial Modeling • Client Accounting—and more on the way!

• NEW CBASIC23 applications:

• REAP (Real Estate Acquisition Programs).

Software from Cybernetics?

RM/COBOL—The new standard for microcomputer COBOL!! The only COBOL for CP/M (also on TRSDOS & UNIX) with alternate keys (multi-key ISAM), CRT screen handling, Interactive debug, and the most useful Level 2 features. Compatible with RSCOBOL5—but runs faster.

TRS-80', Model II CP/M—The fastest Mod II CP/M with the most features. Outstanding teaching documentation for newcomers to CP/M, multiple CRT emulation, down loading package, support for CORVUS 10 Mb hard disk. Many additional user-oriented features.

Plus existing CBASIC2 packages:

APH7 (Automated Patient History)

Osborne & Assoc—Payroll • Payables/Receivables • General Ledger

NAD" (Name and Address)

PMS (Property Management System) Inquire tor details

Trademarks of. 'Ryan-McFarland Corp., 'Compiler Systems, Inc., 'Digital Research, "Bel Telephone Laboratories, Inc.. *Tandy Corp., "Verbatim, Inc. 'Cybernetics. Inc.. BStruc lured Systems Group. Inc.. 'Small Business Applications, Inc.

And system software packages: MAGIC WAND' Editing/Word Processing CBASIC2 Compiler BASIC QSOPT" Soft Merge Package

Distributed in U K. by:

Microcomputer Applications Ltd

Riverside Court, Caversham. Reading, England

TEL:(0734) 470425

8041 Newman Ave., Suite 20B Huntington Beach, CA 92647 (714) 848-1922

The world-famous SHIVA'" Multi-User Real-Time Multi-Tasking Virtual Operating System with its unique VIRTUAL-PERSONALITY'" disk-resident library of interface routines and Virtual R.A.M. mapping is now available in two versions: SHIVA" 1.2 for 8-bit C.P.U.'s and SHIVA'" 1.6 for 16-bit processors. SHIVA'" 1.2 pioneered the high-powered Virtual Operating System (VOS) for microprocessors with its user-reconfigurable Virtual R.A.M. assignment for up to 16-users or real-time tasks. Now SHIVA'" 1.6 continues Omega Researches commitment to non-obsolescence and system superiority by extending SHIVA™ into the 16-bit world of the 80's. SHIVA'" 1.6 syntax is upward-compatible with SHIVA'" 1.2, allowing SHIVA'" users to recompile SHIVA'" 1.2 programs to run under SHIVA" 1.6 easily, so users may purchase SHIVA" 1.2 now. and move up to a 16 bit processor later as their needs dictate with no fear of "software obsolescence." SHIVA" 1.6 is upward compatible with CP/M or CDOS files and programs through its VIRTUAL-PERSONALITY" disk-resident subroutines, supports hard disks as well as single or double-density floppies, features Logon and password protection, and features executive shell commands similar to UNIX in structure and versatility. SHIVA'" interfaces currently to M icrosoft Basic, Cobol. and Fortran; C; Forth; UCSD Pascal Programs; Pascal/M; CBASIC-2; APL; ALGOL-60; LISP; PL/I; MAC; and new interfaces are continually in development to keep SHIVA'" users State-of-the-Art.

SHIVA" 1.2 is available for 8080. 8085, 6800, 6502, and Z80-BASED SYSTEMS INCLUDING CROMEMCO, NORTHSTAR, VECTOR GRAPHIC. SWTP, DIGITAL GROUP, ALTOS. IMS, APPLE II, ITHACA INTERSYSTEMS, and TELETEK disk controllers. 6809 C.P.U. version is in development.

SHIVA'" 1.6 is available for 8086/8088/ and Z8000-2 based systems, with versions in development for 68000 based systems.

Both SHIVA" versions 1.2 and 1.6 provide full disk utilities for all users. SHIVA'" 1.6 upgrades are available to registered SHIVA" 1.2 users within one year of purchase of SHIVA" 1.2 for half the current list price. SHIVA™ — The State-of-the-Art in microprocessor operating systems.

SHIVA'" 1.2

R.A.M. addressing to 1.048 megabytes on a

Z80A-based system

Minimum system R.A.M. (single user): Additional R.A.M. per user:

4K

2K

Maximum tt of users or tasks:

16

Maximum tf of physical and logical drives;

128

R.A.M. Bank capacity:

16-64K

Banks (1.048

megabytes) 1400.00

System prices:

SHIVA'" 1.6

R.A.M. addressing to 1 28 megabytes on a .

■ ■

Z80O0-2 system

Minimum system R.A.M. (single user) Additional R.A.M. per user:

4K

2K

Maximum # of users or tasks:

16

Maximum U of physical and Logical drive:

256

R.A.M. Bank Capacity:

16-8

megabyte banks

(128

megabytes)

System prices:

$650.00

Complete Documentation Included: Documentation available separately for S50.00. Signed license agreement must be returned prior to all shipments.

(Applicable to later purchase of SHIVA" system)

CP/M is a trademark of Digital Research • CDOS is a trademark of Cromemco, Inc. • UNIX is a trademark of Bell Laboratories SHIVA'", VIRTUAL-PERSONALITY'-, and OMEGA RESEARCH™ are trademarks of OMEGA RESEARCH'".

P.O. Box 479, Linden, Ca. 95236 (209) 334-6666

9 am to 5 pm Mon. - Frl.

Circle 239 on inquiry card.

BYTE February 19B1 317

Turn Your COSMAC VIP into a Frequency Counter

Andrew Modla

5 Derby PI

Newtown PA 18940

Many electronic construction projects include a decade-frequency counter somewhere in their hardware. For example, I have seen decade-frequency counters in pH meters, digital voltmeters, capacitance meters, tachometers, digital thermometers, camera shutter-speed meters, event counters, etc. This article describes a frequency counter that is somewhere else—in software. This application is an example of the elimination of hardware by using software techniques. No additional hardware is required. Your microcomputer can replace decadecounter hardware in each of the construction projects named above.

I programmed my RCA COSMAC VIP microcomputer to perform as a general-purpose, audio-range

( FREQUENCY^ ^COUNTER J

1

9

ERASE DISPLAY

CALL MACHINE LANGUAGE COUNTING PROGRAM

DISPLAY 5 DIGITS

WAIT 2 SECONDS

Figure 1: General flowchart for a program that enables a microcomputer to act as a frequency counter.

318 February 1981 © BYTE Publications Inc

decade-frequency counter. The program will count in the 1 to 11,004 Hz range. It checks the transitions of the COSMAC 1802 microprocessor EF4 input flag for one second. The binary count taken is then converted to a decimal value for display on the video monitor. After two seconds to show the count, the program begins to count again.

The program derives its accuracy from the crystal clock that runs the microprocessor. Timed program loops check the input line at precise intervals to obtain a count. Figure 1 shows the flowchart of the program. The program is shown in listing 1. It consists of a COSMAC VIP CHIP-8 interpretive-code main program for control and display, and an RCA CDP1802 machine-language subroutine to perform the counting function.

One of the parameters passed to the machine-language subroutine is a time parameter that, when incremented to zero, gives a precise 1-second interval used in counting. The COSMAC VIP has a 3.521280 MHz crystal. If you use a different crystal, the following formula will provide a number that, when subtracted from 65,536, will count for one second:

T =

number of clock cycles in 1 second

number of clock

cycles to execute

looping instructions

106 clock cycles (1 second)

s\ : A

2 machine 8 clock cycles cycles

machine cycle instruction

F X 106

X (5 instructions)

160

Circle 240 on inquiry card.

Quiet Designs

Preformatted Disks:

Compatible with Lanier 'No Problem', Lanier 90/100, Micom 2000/2001, A.M. 425, C.P.T. 6000/8000, Canon

Standard Disks

For all systems using unformatted disks

Head Cleaning Kits

Kits for 5'/4" and 8" drives

Flip-Sort™

Durable, Dust Proof, Desk Top Disk Storage and Retrieval System.

*W^

Quiet Designs

Quiet Designs Inc.

1330 W. Robinhood Dr.,

Suite F

Stockton, CA 95207

Ph.(209)957-8631

Quiet Designs Inc. 473 Macara #706 Sunnyvale, CA 94086 Ph.(408)739-5215

Quiet Designs of California 1030 W. Maude #512 Sunnyvale, CA 94086 Ph. (408) 730-0170

Quiet Designs International 5940 F #2 Road Richmond, British Columbia, Canada V7C 4R9 Ph. (604) 273-9710

Personal Computing

Festival

now a part of the National Computer Conference '8!

May 4-7, 1981

McCormick Place

Chicaqo, Illinois

Let the convenience, fascination and power of computers bring new dimensions to your personal life. Over 30 informative sessions at the Personal Computing Festival offer a remarkable view of the many ways w^ you can put computers to work for W you. Hands-on exhibits give you a

chance to test the capabilities of equipment designed for •^ use in your home, office, fc or classroom as the PCF joins NCC '81 in the main exhibit area for the first time. Learn how computers can develop an investment portfolio or compose music; create a picture or calculate commissions on sales; control your furnace or do your homework. See applications you never thought of in special demonstration area. Most important of all —find out how computers can make life better for you — personally!

Register for one full day for S10.00 (includes Personal Computing Digest) —or attend the full threeday session for S30.00. |lf you prefer, register for the full NCC '81 session — S60 fee includes PCF registration. For discount air fares, airline reservations, hotel and show information or to preregister CALL TOLL FREE 800-556-6882

aluips

A conference within a conference sponsored by the American Federation of Information Processing Societies, Inc.

BYTE February 1981 319

ADDRES

S CODE

COMMENTS

0200

00E0

ERASE DISPLAY

0202

A3FB

I = ADDR OF 5-BYTE DECIMAL-CONVERSION AREA

0204

0300

CALL MACHINE-LANGUAGE COUNTING PROGRAM

0206

AA08

TIME PARAMETER

0208

6600

V6 = 00

020A

6410

V4 = 10

020C

6510

V5=10

020E

A3FB

I = ADDR OF 5-BYTE DECIMAL-CONVERSION AREA

0210

F61E

I = I + V6 SET I TO DIGIT ADDRESS

0212

F065

V0:V0 = MI V0 CONTAINS DECIMAL DIGIT

0214

F029

I = VO(LSDP) GET DIGIT PATTERN ADDR

0216

D455

DISPLAY DIGIT USING V4 AND V5

0218

7405

V4 + 05 NEXT HORZ TV DIGIT LOCATION

021A

7601

V6 + 01 NEXT DIGIT

021C

3605

SKIP IF V6 = 5

021E

120E

GO TO 20E

0220

6878

V8 = 78

0222

F815

SET TIMER FROM V8

0224

F807

GET TIMER INTO V8

0226

3800

SKIP IF V8 = 00

0228

1224

GO TO 224

022A

1200

GO TO 200

Listing 1: The main frequency-counter program for the RCA COSMAC VIP microcomputer. The program is written in CHIPS interpretive code.

where F is the crystal frequency in MHz. For F = 3.521280, T has the value 22,008. Since the program counts up to zero, the count used in the program is decimal 65,536 — 22,008 = 43,528, or hexadecimal AA08. Note that the VIP microcomputer halves F by using a flip-flop. The maximum frequency that can be counted by the program is T/2 or 11,004 Hz using the above crystal frequency. This assumes no half-cycle of the signal being measured is shorter than five instruction executions, or 45.438 /is.

The counting subroutine uses a five-instruction loop for counting in both the high and low halves of a cycle. Every five instructions, the time-parameter count is incremented by 1. When the time parameter becomes zero

Text continued on page 323

^COUNTING A ^SUBROUTINE J

SET COUNT REGISTER F TO ZERO

LOAD REGISTER E WITH TIME PARAMETER COUNT

TURN OFF TV DISPLAY

I THIS STEP PREVENTS I I DISPLAY PROGRAM ■~1 INTERRUPTS

I I

( RETURN J

Figure 2: Flowchart for the frequency-counting program written for the CDP1802 microprocessor. The program can be adapted to work with almost any microprocessor.

320 February 1981 © BYTE Publications Inc

Listing 2: The counting subroutine for the frequency-counter program written for the RCA COSMAC VIP microcomputer. The subroutine is written in CDP1802 microprocessor code and corresponds to the flowcharts in figures 2 and 3.

Hexadecimal Address

0300 0302 0303

0304 0305 0306 0307 0308 0309 030A

030B 030D 030E 030F 0310 0312

0314 0315 0316 0317 0319

031B 031D 031E 031F 0320 0322

0324

Hexadecimal Code

F800 BF

AF

45

BE

45

AE

E2

61

22

3714

9E

IE

9E

3A0B

3029

IF

IE

9E

3A1B

3029

3F24

9E

IE

9E

3A1B

3029

9E

Instruction Label Mnemonic Operand Comment

•COUNTING PROGRAM

•REGISTER A CONTAINS ADDRESS OF FIVE-BYTE AREA

•SET EVENT COUNTER TO ZERO (REGISTER F)

F COUNT LDI 0

PHI F

PLO F

•SET TIME COUNTER (REGISTER E) TO PARAMETER •TIME COUNTER VALUE FOLLOWS SUBROUTINE CALL

LDA

PHI

LDA

PLO

SEX

OUT

DEC

'START COUNTING

MAIN B4

GHI INC GHI BNZ B

*EF FLAG 1

ON INC

INC GHI BNZ B

•WAIT FOR EF 0

WZERO BN4

GHI INC GHI BNZ B

*EF FLAG 0

OFF GHI

5 E 5 E 2 1 2

ON

E

E

E

MAIN

CONVD

F

E

E

WZERO

CONVD

OFF

E

E

E

WZERO

CONVD

TURN OFF TV DISPLAY

BRANCH IF EF=1 DUMMY INST

ADD 1 TO EVENT COUNTER

BRANCH IFEF = DUMMY INST

DUMMY INST Listing 2 continued on page 322

RACET SORTS — RACET UTILITIES — RACET computes — RACET SORTS — RACET UTILITIES — RACET computes — RACET SORTS - RACET UTILITIES - RACET computes

HARD DISK MULTIPLEXOR

FORTHETRS-80*Modll

NOW YOU CAN HAVE THAT LARGE COMMON DATA BASE!!

• Allows up to 4 Mod IPs to connect to a single controller — up to 4 hard disk drives per controller. Users may access the same tile simultaneously (first-come first-served).

• Uses Cameo controller and standard 10-megabyte cartridge (hard) disk drives along with RACET Hard/Soft Disk System (HSD) software.

• Access times 3 to 8 times faster than floppy. Mixed floppy/hard disk operation supported.

• Compatible with your existing TRSD0S programs -*■ you need only change filenames! All BASIC statements are identical.

• A single file may be as large as one disk. Alternate mode allows 24-million byte record range. Directory expandable to handle thousands of files.

• Includes special utilities — XC0PY for backup and copies, XPURGE for multiple deletions, DCS directory catalog system, and Hard Disk Superzap. FORMAT utility includes options for specifying sectors/gran, platters/drive, logical disk siz6 6tc

HARD DISK DRIVES CONTROLLER $5995 RACET HSD Software $400

Call for multiuser pricing. Dealers call for OEM pricing.

BASIC LINK FACILITY 'BLINK' $25 Mod I, $50 Mod II

Link from one BASIC program to another saving all variables! The new program can be smaller or larger than the original program in memory. The chained program may either replace the original program, or can be merged by statement number. The statement number where the chained program execution is to begin may be specified! (Mod I Min 32K 1-disk)

INFINITE BASIC (Mod I Tape or Disk) $49.95

Extends Level II BASIC with complete MATRIX functions and 50 more string functions. Includes RACET machine language sorts! Sort 1000 elements in 9 seconds!! Select only functions you want to optimize memory usage.

INFINITE BUSINESS (Requires Infinite BASIC) $29.95

Complete printer pagination controls — auto headers, footers, page numbers. Packed decimal arithmetic — 127 digit accuracy +, -, *, /. Binary search of sorted and unsorted arrays. Hash codes.

BASIC CROSS REFERENCE UTILITY (Mod II 64K) $50.00

SEEK and FIND functions for Variables, Line Numbers, Strings, Keywords. 'All' options available for line numbers and variables. Load from BASIC — Call with 'CTRL'R. Output to screen or printer!

0SM $75.00 Mod I, $150.00 Mod II

Disk Sort/Merge for RANDOM files. All machine language stand-alone package for sorting speed. Establish sort specification in simple BASIC command File. Execute ifom DOS. Only operator action to sort is to change diskettes when requested! Handles multiple diskette files! Super fast sort times — improved disk I/O times make this the fastest Disk Sort/Merge available on Mod I or Mod II.

(Mod I Min 32K 2-drive system. Mod II 64K 1-drive) UTILITY PACKAGE (Mod II 64K) $150.00

Important enhancements to the Mod II. The file recovery capabilities alone will pay for the package in even one application! Fully documented in 124 page manual! XHIT, XGAT, XCOPY and SUPERZAP are used to reconstruct or recover date from bad diskettes! XCOPY provides multi-file copies, 'Wild-card' mask select, absolute sector mode and other features. SUPERZAP allows examine/change any sector on diskette include track-0, and absolute disk backup/copy with I/O recovery. DCS builds consolidated directories from multiple diskettes into a single display or listing sorted by disk name or file name plus more. Change Disk ID with DISKID. XCREATE preallocates files and sets 'LOF' to end to speed disk accesses. DEBUGII adds single step, trace, subroutine calling, program looping, dynamic disassembly and more!!

DEVELOPMENT PACKAGE (Mod II 64K) $125.00

Includes RACET machine language SUPERZAP, Apparat Disassembler, and Model II interface to the Microsoft 'Editor Assembler Plus' software package including uploading services and patches for Disk I/O. Purchase price includes complete copy of Editor Assembler + and documentation for Mod I. Assemble directly into memory, MACRO facility, save all or portions of source to disk, dynamic debug facility (ZBUG), extended editor commands.

COMPROC (Mod I — Disk only) $19.95

Command Processor. Auto your disk to perform any sequence of instructions that you can give from the keyboard. DIR, FREE, pause, wait for user input, BASIC, No. of FILES and MEM SIZE, RUN program, respond to input statements, BREAK, return to DOS, etc. Includes lowercase driver, debounce, screenprint!

CHECK, VISA, M/C C.O.D., PURCHASE ORDER TELEPHONE 0R0ERS ACCEPTEO (714] 637-5016

•TRS-80 IS A REGISTERED TRADEMARK Or TANDY CORPORATION

RACET SORTS - RACET UTILITIES — RACET computes — RACET SORTS — RACET UTILITIES — RACET computes •

£- RACET COMPUTES -^

702 Palmdale, Orange, CA 92665

■ RACET SORTS — RACET UTILITIES — RACETcompu tes

Circle 241 on inquiry card.

February 1981 © BYTE Publications Inc 321

Listing 2 continued:

0325

IE

0326

9E

0327

3A0B

0329

F805

032B

A7

032C

F803

032E

BC

032F

F88F

0331

AC

0332

9F

0333

5C

0334

1C

0335

8F

0336

5C

0337

1C

0338

EC

0339

F8 00

033B

AD

033C

9F

033D

BE

033E

8F

033F

AE

0340

8E

0341

F7

0342

AE

0343

1C

0344

9E

0345

77

0346

BE

0347

2C

0348

3B 51

034A

ID

034B

9E

034C

BF

034D

8E

034E

AF

034F

30 40

0351

8D

0352

5A

0353

1A

0354

1C

0355

1C

0356

27

0357

87

0358

3A39

035A

E2

035B

69

035C

D4

0391

INC

GHI

BNZ •CONVERT BINARY TO DECIMAL "FIVE-BYTE AREA FOR STORING CONVD LDI

PLO

LDI

PHI

LDI

PLO

GHI

STR

INC

GLO

STR

INC

SEX ZCNT LDI

PLO

GHI

PHI

GLO

PLO SUBREG GLO

SM

PLO

INC

GHI

SMB

PHI

DEC

BNF

INC

GHI

PHI

GLO

PLO

B BORROW GLO

STR

INC

INC

INC

DEC

GLO

BNZ

SEX

INP

SEP TABLE § 1027

i E803

§ 6400

§ 0A00

§ 0100

E

E

MAIN

(VALUE IN REGISTER F)

DECIMAL NUMBER IN REGISTER A

5

7

03

C

8F

C

F

C

C

F

C

C

C

0

D

F

E

F

E

E

E C E

E

C

BORROW

D

E

F

E

F

SUBREG

D

A

A

C

C

7

7

ZCNT

2

1

4

NO. OF BYTES

SET REGISTER C TO CONVERSION TABLE

STORE RF (FOR DEBUGGING PURPOSES)

SET X TO C

SET COUNTER TO ZERO

MOVE RF VALUE TO RE

SUBTRACT TABLE ENTRY FROM RE SUBTRACT MEMORY

NEXT TABLE BYTE

SUBTRACT BORROW

ORIGINAL TABLE BYTE

ADD 1 TO COUNTER MOVE RE TO RF

STORE DECIMAL DIGIT NEXT DIGIT LOCATION NEXT TABLE ENTRY

SUBTRACT 1 FROM NUMBER OF BYTES

TURN ON TV

RETURN

10000

1000

100

10

'Trademark of Western Digital, ■■' v* 'Trademark of Digital Research,; ~ *f 'Trademark of University of Oilifar'riJa:

9

Copyright ©I960. Digiaomp Research All rights reserved.

New FASCAHOO™ CPU mates today's popular UCSD Pascal language to your S-100 system. With both a Z80 processor and the Pascal Microengine' aboard, PASCAUOO gives you the power of software data structuring without sacrificing speed, memory space—or even your current Z80, 8080 and CP/M2 software.

Greater Speed. Up to 5 to 10 times faster than usual S-100

implemen

tations

of

UCSD Pascal.

More Memory. Up to

128K bytes of memory, plus an optional 1M extended address feature.

Better Performance.

Complies with the new IEEE standard—PASCAL-100 has upward compatibility built in.

Dealer/OEM Inquiries welcomed

For complete information—fast—mail this ad or call us

name mie

Company

Address

Slare

Digicomp Research TerraceHill. Ithaca NY 14850 (6D7)273t5§

. Phone

322 February 1981 © BYTE Publications Inc

Circle 242 on inquiry card.

Circle 243 on inquiry card.

f CONVERT^ V^ COUNT J

SET R7 TO

5

(NUMBER OF BYTES)

SET RC

TO CONVERSION TABLE

'

'

SET RD TO 0

DIGIT COUNT

STORE DIGIT COUNT RD AT RA, RA+ 1

MOVE

RF TO RE

-1

'

ADD 2 TO RC NEXT TABLE ENTRY

SUBTRACT TABLE ENTRY FROM RE

SUBTRACT 1

FROM R7

(NUMBER OF BYTES)

/•"bor

ROW^\ YES

? yS

/R7

.rjV NO

Tno

3 yS

ADD 1 TO RD DIGIT COUNT

YES

TURN ON TV

MOVE

RE TO RF

S

I RET

URN J

Figure 3: Flowchart for the binary-to-decimal-conversion program. RA contains the address of the digit storage area.

Text continued from page 320:

(this 16-bit value will overflow to zero at 65,536), the binary-to-decimal-conversion portion of the subroutine gets control. This routine successively subtracts multiples of ten stored in a table from the binary number and stores decimal digits each time the frequency count underflows.

Once you have your frequency counter running, you might want to modify the program to check EF2 instead of EF4 input. With this change, sine waves on EF2 can be counted using the tape-input line of the VIP.

Other useful applications for the frequency-counter program are the alignment of a modem kit like the Pennywhistle 103 and the adjustment of cassette-tape clock interfaces.

Even if you don't have a COSMAC VIP, you can program your microcomputer to perform frequency counts using the flowchart contained in this article. Happy counting I ■

THE PRACTICAL APPROACH

TO MULTI-USER MULTI-TASKING APPLICATIONS

OSM'S NEW EXPANDABLE MULTIPROCESSOR, MULTI-USER SYSTEM MODEL 6500

MODEL 6500 FEATURES:

— Up to 6separate users per mainframe (10 in March, 1981). Each user has their own system consisting of Z80A CUP, 64K memory console and optional local printer I/O.

— S100 Bus and CP/M2.2' compatible. User and master processors do not communicate on the S100 Bus enabling users to operate at full speed.

— User processors are connected to the master processor through a high speed parallel bidirectional data channel.

— Multi-user System Executive. Unlike MP/M® there is no performance degradation as users are added.

—Users share common disk storage and master printer. The master processor handles disk (floppy and hard) access and printing, as well as automatic master printer spooling.

— Each user has a system reset button. lfanyoftheusers,whetherlocalor remote (thru MODEM), should "crash", he may reset his CPU by depressing the console break key. Other users will not be affected providing complete autonomy. —Additional features include expandability to 100+ user terminals, interfaces to any ASCII CRT terminal, messages can be passed among users, and multi-level file security and file sharing interlock are provided.

CP/M and MP/M are registered trademarks of Digital Research.

OSM COMPUTER CORPORATION

2364 WALSH AVENUE • SANTA CLARA. CA 95051 (408) 496-6910 • TWX: 910 338 2099

BYTE

BACK IMUE&

FOR MLE

The following issues are available:

1976: July and November

1977: March, May thru December

1978: February thru October, December

1979: January thru December except March

1980: January to current issue except February and October

Cover price for each issue through August 1977 is $1.75

Domestic; $2.75 Canada and Mexico; $3.75 Foreign.

September 1977 through October 1979 issues are $2.50

Domestic; $3.25 Canada and Mexico; $4.00 Foreign.

November 1979 to current is $3.00 Domestic; $3.75 Canada

and Mexico; $4.50 Foreign.

Send requests with

payment to:

BYTE

Publications

70 Main St.

Peterborough

NH

03458

Attn:

Back Issues

February 1981 © BITE Publications Inc 323

Speech

syhtmsis

&Y TOM SlOA*.

T

WMATS CO/A

ICr ON f)

#

t

-"/k>\

-O

*

%

if i^

aC:

■^>s^

pt-^^^'

-^v

^#

TwELL, HE'S WRITING- A 4 VOICE -SPEECH SYNTHESIS PROG-RAM,

WE'LL NEED *k DIFFERENT PEOPLE FOR THE V01CE5

—-^-T—"SHELUT HEi.t.oX.HELLO^

NOW WHEN THE LED FLASHES,ITS sYOUR QUE

OK MEN WE'RE READY FOR A TEST.

OH NO/ YOU GOT

.LARYNGITIS/,

CEE ITS NICE WHEN YOUR COMPUTER RUNS PROPERLY

324 February 1981 © BYTE Publications Inc

Programming Quickies

KNIGHT: A Knight's Tour Problem in MMSFORTH

Ulrich Frei, Aalweg 13, D 7922 Bolheim, West Germany (BRD)

1 0 DY ■/. -2 5 DY /.

2 XF'OS '/.

2 1 HY

-2 6 HY

YF'OS V.

2 2 HY ■/. 1 -1 7 HY ■/. XNEU ■-: 2 YNEU

I run MMSFORTH on my Radio Shack TRS-80 Model I. I wrote the KNIGHT program in listing 1 to compare the speed of FORTH with other languages. The program in listing 1 shows the trial-and-error solution of the Knight's Tour problem (ie: to find a sequence of Knight moves such that each chessboard square is visited exactly once) displayed on the screen while the solution is being worked out. A modified version of this program that does not give a dynamic display of each move was compared in execution speed and relative program size to the same algorithm coded in TRS-80 Level II BASIC and in Z80 machine code. The results are given in table 1. ■

< KNIGHTSTOUR

: F'OSCHK XF'OS B YF'OS B XNEU b

i b direct a nx a

I B UIRECT S DY B YNEU B BOARD B

F'ART 3 OF 4

+ XNEU X + YNEU :'. 0

XNEU B XF'OS V. YNEU B YF'OS

YF'OS B 2 - 2 * XF'OS B 2 - 8 N B XF'OS 0 YF'OS B BOARD V.

BLOCK 82 >

1 N +'/. F'TC N ? '. DISF'L. MOVE ) UF'DATE BOARD ) !

YF'OS B 2 - 2 * XF'OS B 2 0 N B DIRECT V. 0 XF'OS B

XF'OS B N B DIRECT B DX B YF'OS B N B DIRECT B DY B

8 * F'TC " YF'OS B BOARD

XF'OS '/.

YF'OS '/'.

N 0 1 - N /.

Listing 1: The program KNIGHT, a Knight's Tour problem written in MMSFORTH. This listing was made on a European printer, which necessitates the American user to change all the percent signs (%) to exclamation points (!). The exclamation point is actually the familiar "store-value" variable in FORTH and is used in the words ( I j and { + I ).

! KNIGHTSTOUR

< TO START. TYF'E 80 LOAD <ENTER>

I. REF'LACE '/. WITH EXCLAMATION-MARK

FART 1 OF 4

BLOCK 80 )

) )

11 11 2ARRAY BOARD

64 ARRAY DIRECT

7 ARRAY DX 7 ARRAY IiY

2 VARIABLE XNEU 2 VARIABLE XF'OS 1 VARIABLE N

< KNIGHTSTOUR

2 VARIABLE YNEU 2 VARIABLE YF'OS

( LOAD ARRAY-ROUTINE >

< BOARD-REF'RESENTATION >

< STORAGE OF DIRECTION )

< POSSIBLE DISF'LACEMENTS >

< FUTURE POSITION )

< CURRENT F'OSITION )

< NUMBER OF MOVE )

F'ART 2 OF 4

BLOCK Bl >

-1 I J BOARD 0 I J BOARD

CLS

12 0 DO 12 0 DO

10 2 DO 10 2 DO

12 2 BOARD '/.

43 0 DO 0 I DIRECT '/. LOOF'

8 0 DO 8 0 IlO I 2 « J 8 * F'TC "

0 0 F'TC " 1 "

2 0 IiX '/. 1 1 DX '/. -1 2 DX V. -1 3 DX V. 16 DX '/. 2 7 DX '/.

LOOF' LOOP LOOF' LOOP

LOOF' LOOF'

< KNIGHTSTOUR : KNIGHT

F'ART 4 OF 4

CLS INIT BEGIN F'OSCHK

IF MOVE

ELSE N 0 DIRECT 0 7 IF BACK

BEGIN BACK N B DIRECT END THEN 1 N B DIRECT +','. THEN

N B END

Language

Z80 machine language

MMSFORTH

Level II BASIC

Execution Time

1 min, 06 sec

30 min 9 hr, 52 min

Relative Size of Program

1

27

539

Table 1: Comparative execution times and program sizes of three versions of the same program. The same algorithm was used to code each of the three versions of the Knight's Tour problem, one version each in 7.80 machine language, MMSFORTH, and Level U BASIC. The machine used was a Radio Shack TRS-80 Model I.

February 1981 © BYTE Publications Inc 325

A Heating and Cooling Management System

Tom Hall 8500 Cameron Rd Austin TX 78753

This article describes a practical application for computer-automated management of your home's heating and cooling needs.

Let's review some simple facts about the home that will be helpful in planning a home heating and cooling management system. Of course, you may have a few of your own to add after reading the list:

• The kitchen is usually warmer than the rest of the house during cooking periods.

• The laundry room, while being used, is usually warmer than the rest of the house.

• During normal sleep periods, we care only about the temperature of the bedrooms.

• In a two-story house, the temperature upstairs is usually significantly warmer than downstairs.

• We do not care what the temperature is (within reasonable limits) in the house when we are away.

Now let's take a look at the basic weakness of most central heating (and air conditioning) units. There is only one thermostat and it is located in one room. Therefore, only the tem

perature of that room is really regulated, and the thermostat must be manually adjusted. Now let's examine a system that can be used to help manage the heating and cooling of a home. The components of the system are the computer, the central

Your personal computer can optimize your home heating and cooling system even when you're away from home.

heating unit, a real-time clock, a switch that indicates whether anyone is at home, and an array of computercompatible temperature sensors.

Designing the System

The first step is to determine how many of the temperature sensors you will need. For a week or so, measure the temperature in each room of your house about six or eight times a day. At least two of these times should be during cooking and washing periods. You will probably find that the

temperatures in all the bedrooms are about equal. Several other rooms will probably be similar under most conditions. The number of sensors needed for your home will vary with your conditions, but you will probably not need a sensor in every room. You will want to place a temperature sensor outside, in the kitchen, in a bedroom, and in any room that shows a temperature difference of several degrees in a day's time.

To approximate the thermal capacity of each area, determine the number of cubic feet of space served by each sensor. This is necessary to compute the average temperature of the house. From this information, we will decide whether to turn on the heating (or cooling) system or to just balance the temperature throughout the house by turning on blower fans. Of course, when we do not care about the temperature balance (such as when we are sleeping or away from home), it will not be controlled as tightly.

The flowchart of figure 1 presents a possible control routine for the hardware described here. It is written for winter with the assumption that our main concern is keeping the house warm.

* NORTH STAR USERS *

8" FLOPPY SUBSYSTEM HAS DAWNED ON THE HORIZON

COMPLETE WITH MANUALS. SOFTWARE, HARDWARE FULLY INTEGRATED, READY TO RUN

* Foully compatible with North Star hardware * Allows use of 8 and'orS" drives * Detailed, 80 paj;e manual included * Background print (asks * Support* Itoppy files up to 4.2 MB * Simple, plug-in operation * Fully CP/M"' compatible *File security * Extensive utilities included

DMA-DOS Software S200

Dynamic Microprocessor Associates Disk Operating System

Tarbell Double Density Controller $420

Cables $40

Dual Shugart 8" 800R drives in cabinet with fan

and power supply $1,250

Total package $1,910

Prices and otters subject to change without notice

» WE WILL PAY SHIPPING ON PREPAID ORDERS (Continental USA only). WE HAVE NO READER INQUIRY NUMBER. PLEASE WRITE OR CALL. '

JOHN D. OWENS ASSOCIATES, INC.

12 SCHUBERT STREET, STATEN ISLAND, NEW YORK 10305 OVERSEAS CALLERS: TWX 710 588 2844 or call (212) 448 6298*DOMESTIC CALLS: (212) 448 6283 (212) 448 6298 (212) 448 2913

326 February 1981 © BYTE Publications Inc

f ENTER j

LOAD TEMPERATURE LIMITS FOR UNOCCUPIED HOUSE

INITIATE

TURN OFF SEQUENCE

FOR HEAT

TURN FAN OFF

WAIT FOR TEMPERATURE MONITOR INTERRUPT

MEASURE ALL TEMPERATURES

YES

LOAD TEMPERATURE LIMITS FOR OCCUPIED HOUSE

CALCULATE AVERAGE TEMPERATURE OF HOUSE

YES

INITIATE

TURN ON SEQUENCE

FOR HEAT

JL

LOAD TEMPERATURE LIMITS FOR SLEEP PERIOD

YES

INITIATE

TURN OFF SEQUENCE

FOR FAN

Figure 1: Flowchart for a winter temperature-control program. Use of this flowchart assumes that the computer has control of the house thermostat and fans and that it can sense temperature through several remote temperature transducers, the sleep/waking status through a real-time clock, and the home/gone status through a user-controlled remote switch.

The flowchart is self-explanatory, but several notes are in order. When installing an interface to your heating system, be sure to leave the existing thermostat active for safety reasons. Also, if you are not familiar with the workings of your heating unit, ask for assistance from a professional.

Hardware Description

Figure 2 demonstrates two versions of the remote switch that tells the computer whether or not anyone is home. The version in figure 2a uses one wire from the computer connecting through the remote switch to a natural ground (for example, a water

pipe). The software that samples the STATUS bit should do so several times in order to be sure of the remote switch's position.

Because the use of the home's ground may produce a false reading (due to the "noise" of household appliances, among other things), the more complex circuit of figure 2b provides a foolproof solution; its disadvantage is that it requires three extra remote lines. The 1 k-ohm resistor close to the 5 V supply limits the current coming from the source in case of an accidental short. The IC4a and IC4b pair form an RS latch that holds the most recent value of the remote

switch (which is a momentary closure switch). This circuit has the advantage of requiring only a conventional electrical ground. The AT HOME OVERRIDE switch is located close to the computer so that the user can change the value of STATUS without throwing the switch at the remote location.

Figure 3 is a schematic of the temperature sensor, which is based on a National Semiconductor LX5700 temperature transducer. The circuit converts the analog output of the transducer to a pulse frequency via a timer circuit. We can later convert this in

Text continued on page 330

February 1981 © BYTE Publications Inc 327

(2a)

r

| +5V

REMOTE I

SWITCH I HOME

GONE

^

L.

(2b) I

REMOTE SWITCH

IK -ff -VW

•5.6K >5.6K

GONE

47K -jj "^/V

j 47K -. // W^

~fj

_l

TtV

n

LOW = AT HOME HIGH=GONE

F5V

4.7MF 10V

I'"

4.7MF

COMPUTER END RECEIVER

1C4 74COO

^>G>M

f5V

IC3

74L04

8 3^V^> STATUS ^ToHO«

10K

10K -vw

AT HOME OVERRIDE

Figure 2: Schematic diagram for the home/gone remote switch. The version of this switch given in figure 2a is simpler, using fewer components and wires, but it may be vulnerable to electrical "noise" in the natural (house) ground it makes use of. The version in figure 2b is more complex, but it uses a conventional (equipment) ground and two NAND gates wired as a set-reset (RS) latch that remembers the most recent switch position.

System-One:

An information storage and retrieval system offering a simple yet powerful inquiry by example operator interface. The inquiry by example process allows an operator, regardless of formal training, the ability and opportunity to take advantage of a powerful retrieval tool. For those in need of a more formal approach supporting boolean expression evaluation, keep an eye on future ml\Dex product releases.

For more detail, see our earlier Nov/Dec 1980 ads in BYTE.

"TrVZW System-One, for UCSD Pascal 1.5. 11.0, or PASCAL/M with sample databases

and manual $250

mINDex manual only $ 30

Pascal Resources:

Since Pascal is the preferred language at mlVDe\ , and because of its growing popularity and acceptance, mIIMDex is considering the development of a major MINDexCHANGE Softsource, a database entitled "Pascal Resources."

If you or your company have products or services related to the Pascal language and we have not already contacted you, please contact us for further information on this development.

If you would be interested in obtaining a copy of such a database in either machine readable form, hard copy, or microfiche format, please drop us a line stating your preference.

Current MINDexCHANGE Softsources in the

form of System-One compatible text files include:

1. Micro-Op-System Resources.

2. Micro-Language Resources.

3. Micro-Peripheral Resources.

Softsources are $30 each, or $75 for the set. Each database includes a related thesaurus of key words for use with System-One.

Dealer inquiries are invited.

Contact: ml\Dex Infosystems

81 Centennial Loop, Suite A Eugene, Oregon 97401 Ph: (503)485-5827

Shipped on 8" single-density soft sectored diskettes.

J

UCSD Pascal is a registered trademark of The Regents of the University of California. PASCAUM is a trademark of Sorcim.

328 February 1981 © BYTE Publications Inc

Circle 244 on inquiry card.

AIM 65

Circle 245 on inquiry card.

AIM 65 is fully assembled, tested and warranted. With the addition of a low cost, readily available power supply, it's ready to start working for you. It has an addressing capability up to 65K bytes, and comes with a user-dedicated 1K or 4K RAM.

• Thermal Printer

• Full-Size Alphanumeric Keyboard

• True Alphanumeric Display

• Proven R6500 Microcomputer System Devices

• Built-in Expansion Capability

• TTY and Audio Cassette Interfaces

• ROM Resident Advanced Interactive Monitor

• Advanced Interactive Monitor Commands

PRICE: $389.00

Plus $4.00 UPS (shipped in U.S. must give street address), $10 parcel post to APO's, FPO's, Alaska, Hawaii.Canada, $25 air mail to all other countries

We manufacture a complete line of high quality expansion boards. Use reader service card to be added to our mailing list, or U.S. residents send $1.00 (International send $3.00 U.S.) for airmail delivery of our complete catalog.

ENTERPRISES

INCORPORATED

2951 W. Fairmount Avenue • Phoenix, AZ 85017 • (602) 265-7564

REMOTE SENSOR

COMPUTER END

* * +1% METAL FILM 1/2 W

Number Type +5 V GND

IC1

LX5700

—

IC2

LM3046N

—

IC3

7404

14

IC4

7400

14

Figure 3: Schematic diagram for the remote temperature sensor. 1C1 is the temperature sensor, while IC2 is a transistor array that exhibits stability over a wide temperature range. The output bit CNEN must be high to allow the pulse train CN to appear. The frequency of the pulse train at CN is proportional to the temperature being sensed.

$GOLD DISK$ CP/M® Compatible Z-80 Software

Available for all 8-5" ss-sd IBM format systems including TRS-SO", Northstar. SD Systems,

Also available on 5" double density Superbrain"

GREAT LOOKING LETTERS & REPORTS! REPORT WRITER

TaketheAGONYoutofterm paper writing AUTO footnoting, table spacing, headings

NO RETYPING TO INCLUDE CHANGES, CORRECTIONS ALWAYS PROFESSIONAL LOOKING LETTERS, FORMS

SIMPLE MULTI-LETTER PRINTING

LEFT AND RIGHT JUSTIFICATION SIMPLE TO LEARN, EASY TO USE

$42

00

UN-CAN YOUR CANNED SOFTWARE! Z-80 DISASSEMBLER

Feel couped up with your canned software? Our Z-80 Disassembler recreates assembly

LANGUAGE SOURCE FILES FROM ABSOLUTE CODE ENABLING USERS TO EASILY TAILOR PROGRAMS TO MEET THEIR SPECIFIC NEEDS. THE PRECONDITIONER ALLOWS THE

Disassembler to decode Ascn. ■ *■""» ppd

*72

00

Credit Cards: Free 24 hr order phone, we'll credit invoice, one day service. checks. m .o.'s: ten workday hold. ca. res: add tax.

BOWER-STEWART & ASSOCIATES

P.O. BOX 1389

HAWTHORNE, CA. 90250

(213) 676-5055

State system & controller, allow time for surface mail. Trademarks- 'Digital Research, "Radio Shack, '"Intertec.

Circle 246 on Inquiry card.

February 1981 © BYTE Publications toe 329

Number Type

+ 5 V

GND

IC5 74198N IC6 DM8556N IC7 DM8556N IC8 DM8556N IC9 DM8556N IC10 7404

24 16 16 16 16 14

12 8 8 8 8 7

RESET COUNT

o

READ

BYTE O

ONE

READ

BYTE E>

TWO

t-5V

CNH Q>

CNG fZ>

CNF [~>

CNE C>

CND Q>

CNC O

CNB \~^>

CNA \~^

"^

£X

IC10 7404

JB>M>ci

-CI> CNENH

-Q> CNENG

-(3> CNENF

£^> CNENE

-Q> CNEND

-Q> CNENC

{^> CNENB

-fj^> CNENA

LOAD

SENSOR I—v.

SELECT I *■

BYTE

5V

A

LOAD

RESET

CLOCK

OD

IC9

MAX COUNT

LOAD

RESET

CLOCK

OD

IC8

12

MAX COUNT

LOAD

RESET

CLOCK

OD

IC7

hSV

MAX COUNT

LOAD

RESET

CLOCK

OD

T

I0D IOC I OB I0A

13

10

I0D IOC I0B

I0A

I0D IOC IOB

IOA

13

10

!0D IOC IOB IOA

IC6 - IC9 ARE DM8556N

-O BO -O Bl -O B2 -D>B3

-O B4 -O B5 -O B6 -O B7

Figure 4: Schematic diagram for a temperature-count accumulator. This circuit allows the computer t o count the pulses from any one of the eight temperature sensors. After the count is finished, the circuit returns the count as an absolute 16-bit number delivered 1 byte at a time. IC5 is an 8-bit shift register that transfers the 8 bits coming from the computer (1B0 thru IB7) to the enable lines of the eight temperature sensors (CNENA thru CNENH) when the load-sensor-select-byte input line goes high. 1C6 thru 1C9 are three-state binary counters that are cascaded to form a 16-bit counter.

Text continued from page 327: resistors forms a constant-current

software to a temperature reading. source. A constant-current source is

In figure 3, the circuit formed by an efficient way of sending power to a

the transistor Ql, the light-emitting remote circuit because the impedance

diode (LED), and their two associated of the power line to the remote circuit

is not critical. Also, a zener diode is present within IC1 to regulate its voltage.

To minimize the number of wires running to the multiple remote sen

330 February 1981 © BYTE Publications Inc

Count Change

(Perl°F Temperature Change

)

(Counts at Hot Water Temperature) —(Counts at 32° F) (Corrected Hot Water Temperature)

To figure the actual temperature 'Temperature \

Table 1: Equations for obtaining corrected temperature readings from the sensors

/T

\in Degrees

(Number of Counts for Unknown Temperature) — (Counts at 32 °F) (Count Change per 1° F of Temperature Change)

sors that this design requires, I used a technique that allows the use of the same wire both to supply power to the integrated circuits and to return the pulse train from IC2. The pulse train from IC2 pulls the power line low enough to be recognized as a logical low by IC3. During the short periods that the power line is low, the capacitor C3, assisted by the constant current coming from the transistorLED pair even when the power line is low, maintains power to the sensor.

The pulse train arriving at IC3 has a frequency that is proportional to the temperature being sensed by ICl. The NAND gate of IC4 allows the CNEN line to control the flow of the pulse train to the CN line.

Figure 4 shows the temperaturecount accumulator that receives the CN signal from any one of eight sensors. The circuits IC6 thru IC9 are each binary counters with three-state outputs (high, low, or disconnect). They will be used to count the number of pulses in a fixed time frame from each sensor in its turn. Figure 5 shows a timing diagram for the temperature accumulator and gives an explanation of its workings.

To calibrate the sensors, a large bucket of ice and a thermometer capable of measuring temperatures from about — 5° F to 120° F are needed. The sensor to be calibrated should be hooked up to the computer in the same way that it will be for remotetemperature sensing. The real-time clock should allow the sensor to count for about 0.5 seconds before the computer reads its count value from the circuit in figure 4. The count for the sensor should be in the range of 3000 to 15,000 counts; this tells us only that the sensor is functioning.

Take each sensor and dunk it in the bucket of ice. Pour in just enough water to cover the ice, stir, and stick the thermometer in. This is called an

LOAD SENSO

1q lu IH7

RESET COUNT

READ BYTE 1

READ BYTE 2

R BYTE I L

INITIALIZE

~fh

~fh

SJ

-fj

READ TEMPERATURE

Figure 5: Overview of the temperature-sensing process. The events must take place in the following sequence: (A) Deselect all sensors by setting IB0 thru IB7 to zeros, then raising the load-sensor-select-byte bit to high. (B) Reset the temperature count with a positive pulse. (C) Select the desired sensor by the above method, but with a 1 going to the IB line of the chosen sensor. (D) After the count is completed, deselect all sensors as in step A. (E) Get the low byte of the count by pulsing the read-byte-1 line. (F) Get the high byte of the count by pulsing the read-byte-2 line. (G) Reset the temperature count as above; then go back to C if more sensors are to be read.

ice-point bath. The count from each sensor is the number of pulses equivalent to a temperature of 32° F. Confirm this reading with your thermometer, which should also read 32° F. If it does not, note the difference in the two readings—this number can be used as a correction factor in the next step.

Take the sensors out of the bucket and pour out the ice water. Rinse the bucket with hot tap water. Then fill the bucket with hot tap water, put the sensors back in the bucket along with the thermometer, and stir again. Read the thermometer and record the count for each sensor at the new temperature. If the reading at 32° F was off, you will have to adjust the new temperature by the same amount. This gives us the corresponding count for each sensor for two temperature

extremes. From this we can easily determine the temperature of a given sensor by using the equations in table 1. Knowing the temperature from each sensor, you can proceed to write a program from the flowchart and start keeping track of your home heating system. ■

1. Lefferts, Peter, Linear Applications 2 (National Semiconductor, Santa Clara, California).

2. Smith, M F, "Using Interrupts for ReadTime Clocks," BYTE, November 1977, pages 50 thru 53.

February 1981 © BYTE Publications Inc 331

Modifying the SwTPC Computer

Thomas J Weaver 825 N Sherry Ave Norman OK 73069

Changing to a newer 6809 microprocessor is a simple way to upgrade a 6800-based computer. In fact, Southwest Technical Products Corporation makes a conversion kit for its 6800 system that includes a 6809 processor board (see photo 1) and complete instructions. The kit can be built in one evening, but does require some modifications to the existing system.

Because of changes that I had already made to my computer, I was able to ignore the modifications suggested for the memory boards and disk controller. However, these changes are not complex, and should not require much time.

What I found most upsetting were the modifications that had to be made to the motherboard. These changes, if made, would not allow the use of the

6800 processor board. Because I have many large 6800 programs in binary form, without source code, it became necessary for me to fix the motherboard so that it would work with either processor board.

Although several of the bus lines are redefined for 6809 use, some of the changes do not affect 6800 operation. For example, the 6809 uses the UD2 line for the active-low FIRQ signal. All told, these are only five incompatible signals.

By installing a five-pole, twoposition switch, it is a simple matter to change the configuration from 6800 to 6809. Most of the wiring attachments to the motherboard can be made in a small area, and a ribbon cable allows the switch to be mounted above the reset and power controls. Other connections must be made to the reset switch and the motherboard power-supply connector. These connection points on the bottom of the MP-B motherboard are shown in photo 2. Table 1 summarizes the

(212) 986-7690

MAIL ORDER ONLY

Micro Computer Your One Stop For. . .Quality and Huge Savlnga

DISCOUNX

QUALITY • DELIVERY • SERVICE

60 E. 42nd St. Suite 411 New York, NY 10017

CENTRONICS

CALL FOR PRICES

ATARI

800—$795

APF

IMl - $495 IM2 - $988

COMMODORE

8K -$729 16K - $888 32K - $1088 2022 - $695 2040 - $1088 8050 - $1435 8032 - $1495

XYMEC

HQ 1000 - $2395

NEC SPINWRITER

5510 - $2795 5520 - $2990

EPSON MX-80 EPSON MX-70

PAPER TIGER

445 & 460

CALL FOR PRICE

SUPERBRAIN*

*32K - $2445 64K - $2645 64KQD - $3395 *32K add-in memory

only $10 with

purchase

*XEROX

1740 RO - $2619 1740 KSR- $2995 1750 RO - $2795 1750 KSR - $2995 1730 - $2195

MAIL ORDER ONLY

Send Certified Check (Personal or Company Checks require 2 weeks to clear.) We pay all shipping and insurance charges except items marked with asterisk. VISA, MasterCharge add 5% N.Y.S. Residents add appropriate sales tax.

* (DENOTES ITEMS SHIPPED FOB. NYC)

PHONE (212) 986-7690

jumpers and traces that must be cut. See figure 1 for the various switch connections.

When the modifications are complete, either processor board may be used by connecting or disconnecting the 6809 reset cable, changing pro

Connection Points

A

UD3 on I/O bus

B

SELECT 5 on I/O bus

C

IC 6 pin 7

D

IC 6 pin 11

E

IC 6 pin 6 (at R12)

h

A12 line on SS50 bus

G

IC 5 pins 5, 6

H

IC 4 pin 2 (on connector line)

1

IC 4 pins 9, 10

J

IC 4 pin 11

K

IC 4 pin 12

L

IC3 pin 6 (at R11)

M

Master Reset line on SS50 bus

N

UD2 line on SS50 bus

O

+ 5 V(at R1, R2, R3, et al)

Y

reset switch

Q

reset switch

R

power supply connector pin 9

jumper:

A — B

H — L

N—v^—0

6.8 k-ohm

P — 6809 reset connector

Q — 6809 reset connctor

cut:

D / / G

near D

I / / K

remove master reset line at mother

board

Table 1: The five-pole, two-position

switch of figure 1 is connected to the

points specified in this table. Note that

not all modifications are made directly

to

the switch; some are jumpers.

Address Translation

of 48 K Bytes

Physical Address

Logical Address

Oxxx

Oxxx

1xxx

1xxx

2xxx

2xxx

3xxx

3xxx

4xxx

4xxx

5xxx

5xxx

6xxx

6xxx

7xxx

7xxx

Axxx

8xxx

Bxxx

9xxx

Cxxx

Cxxx

Dxxx

Dxxx

Table 2: Physical and logical memory

addresses are mapped

in a slightly dif

ferent manner.

332 Februai-y 1981 © BYTE Publications Inc

Circle 247 on inquiry card.

What are Heathkit® owners saying about Buss?

"Keep up the great work. Buss is the most useful, information-packed publication I have encountered in my 15 years in the computing industry." Clara, CA

"Congratulations on Buss's advance information. One issue alone saved me over $150. Total savings about $240 so far!" New Rochelle, NY

"Your Buss paper has been most helpful to me as I'm just getting started with my H8, H17 & H19. Keep up the good work." Maize, KS

This is what people are saying about Buss: The Independent Newsletter of Heath Co. Computers.

Buss is the publication where Heath® owners can give candid reports of their experiences with Heath® and Zenith products. It's mailed first class about every three weeks.

Buss also publishes a directory of over 80 suppliers which is FREE to "subscribers. You can start your subscription with the latest edition or available back issues (about 15 still in stock). 12 issues: $17.97 (overseas airmail $25.00).^ & W. >> c^ 18 issues: $24.95 (overseas airmail $35.00) ^.^.x/j 24 issues: $29.97 (overseas airmail $45.00) Payable in U.S. dollars on a U.S.-bank or by order. Buss, 325-B Pennsylvania Ave., S.E., Washington

%<<?/

international DC

money 20003.

cessor boards, and resetting the fivepole switch. Eventually, I plan to disassemble my binary programs and reassemble them on the 6809; but this system is quite flexible, so there is no rush. This allows me to evaluate and disassemble newly acquired 6800 programs without having to borrow a friend's 6800 system.

The Monitor

The 6809 processor board includes space for four 2716-compatible 2 K-byte programmable-memory integrated circuits. The address locations for the first two circuits overlap I/O port addresses, while the third has addresses identical to the 8-inch floppy-disk controller board (this presents no problem for those using 5-inch floppy disks). The la.st of the four sets of addresses is occupied by the SBUG-E monitor read-onlymemory integrated circuit.

This monitor is slightly different from SwTPC's SWTBUG monitor, for the 6800 processor, but is also similar in many ways. This monitor

Photo 1: To ensure proper operation of the 6809 processor board, in a modified system, resistor R20 should be installed on the solder side of the board, as shown. It is necessary to trim the leads flush with the top of the board, since they will be covered by the NMI/RESET connector.

allows all registers to be examined and set directly, using the Control key, in combination with the register name. For example, keying ControlD allows the user to examine or change the direct-page register. In the SBUG-E monitor:

• all registers may be displayed using the R command, and the system stack may be examined using the S command.

• There are separate commands to boot 8-inch (D) and 5-inch (U) floppy-disk units.

Bring the computer to your senses

The Soundchaser* computer music system transforms the Apple II" into an expandable, professional quality, polyphonic keyboard synthesizer and sequencer. Soundchaser's music modules include a 4 octave keyboard housed in an attractively finished wood cabinet complete with polyphonic interface card, connector and control software. 1he synthesizer voice card provides

3 analog/digital hybrid, studio quality programmable synthesizers. Each synthesizer consists of a wide range, waveform select oscillator, digitally controlled 24 dB/ octave, low pass resonant filter, user definable LFO. fully programmable envelope generators, and a digitally controlled amplifier. System software includes a 4 channel sequencer which supports up to 12 synthesizers!

Explore Soundchaser's musical horizons. Play the sounds at your fingertips.

Keyboard: S650.00,

3 Synthesizer voice card: S350.00.

Write or call for details.

Dealer inquiries invited.

(415) 747-0614

TVtvnssport

>^De5IGN5

Soundchaser is a trademark of Passport Designs, Inc. Apple is a registered trademark ot Apple Computer, Inc.

Marketing: Box 21061. Minneapolis, MN 55421

Headauarters:

Box 478.

La Honda, CA 94020

February 1981 © BYTE Publications Inc 333

Photo 2: Use of a ribbon cable allows a five-pole, two-position switch to be mounted in a convenient location on the front panel.

IC6 PIN 6 (AT R12)

IC5 PINS 5-6 G

IC4 PIN 12 K

MASTER RESET LINE

ON SS50 BUS

POWER SUPPLY CONNECTOR PIN 9

• A memory-dump command (E) produces hexadecimal and ASCII dumps.

• The familiar byte-examine and byte-change command (M) is still implemented.

•A memory-test command (Q) checks a specified block of memory.

• The go (G) command has been restructured to obtain the program execution address from the programcontrol register, rather than hexadecimal location A048.

• The go command also removes software interrupts created by the set breakpoint (B) command.

• All breakpoints may be removed at once using the X command.

• The MIKBUG tape load (L) and punch (P) commands are still present.

Commands which are conspicuous by their absence are J (execute program starting at specified location) and F (find locations containing a specified byte). I hope these commands are included in the next version of the monitor, since I use them frequently, especially while trying to discover why new binary programs refuse to run on my system.

Memory

One of the areas that must be mastered before using the memory check (Q) command is Dynamic

J IC4 PIN 11

0 IC 6 PIN 11

C IC6 PIN 7

I IC4 PINS 9-10

F A12 LINE ON SS50 BUS

P RESET SWITCH

Q RESET SWITCH

Figure 1: The free end of the ribbon cable is connected to a five-pole, two-position switch, according to this diagram.

Address Translation. Basically, memory may have different physical and logical addresses. When powered up, the monitor checks the amount of memory available, and then maps it in 4 K-byte segments, using the following hexadecimal hierarchy: Dxxx, Cxxx, Oxxx, lxxx, 2xxx, 3xxx, 4xxx, 5xxx, 6xxx, 7xxx, 8xxx, 9xxx, Axxx, Bxxx. Up to 56 K bytes of programmable memory may be mapped in this manner. An example of the physical and logical addresses of 48 K bytes is shown in table 2. Since the modifications mentioned do not permit user memory at physical addresses 8000 thru 8FFF for 6800 operation, the memory limit for systems with this modification is 52 K bytes.

The address table for the software interrupts (SWI, SWI2, and SWI3) and the interrupt requests (IRQ and FIRQ) is near the top of the user memory beginning at hexadecimal address DFC0. This table also includes the lower and upper limits for a supervisor-call address table, used in connection with the SWI3 instruction. When an SWI3 instruction is encountered, the following byte is examined. Assume this next byte contains the value n. If the user has provided a supervisor-call address table containing at least n + 1 addresses, the supervisor routine indicated by the (n + l)th address will be executed. If the supervisor-call address table is not present or does not contain enough entries, the regular SWI3 address will be used.

Extras

Several parts of the MP-09 processor board have obviously been designed for expansion. Simple, onboard connectors reconfigure the data rate lines for speeds from 110 to 38,400 bps (bit per seconds), or use the 110 bps line as a Bus Request line. These and other features suggest that SwTPC has specific enhancements in mind.

The FLEX2 (6800) and FLEX9 (6809) 5-inch floppy-disk operating systems from TSC (Technical Systems Consultants) further enhance the use of this modification. Text files, BASIC programs, and source code may be easily transferred from one system to the other since both use the same disk format. Now disks as well as hardware can be used interchangeably with a dual 6800/6809 system. ■

334 February 1981 © BYTE Publications Inc

META TECHNOLOGIES

FOR YOUR DISK SYSTEM

FILE BOX $24£.*.*

DISKETTE STORAGE SYSTEM for 8" disks . . . $29.95

MTC brings you the ULTIMATE diskette storage system, at an affordable price. Storing 50 to 60 diskettes, this durable, smokecolored acrylic unit provides easy access through the use of index dividers and adjustable tabs. Unique lid design provides dust-free protection and doubles as a carrying handle.

PLASTIC LIBRARY CASES

(not shown) An economical form of storage for 10 to 15 diskettes, and is suitable for your bookshelf! Case opens into a vertical holder for easy access.

5Vi-inch diskette case $3.25

8-inch diskette case $3.50

TRS-80™ PRODUCTS

•I tun is liirrimr

MHjm&OFv hash: nEciuam

*V- OTHER 7KVSTEKKS

fm- fin- TI1S-SO

NEWDOS/80 by Apparat $ 149.95

NEWDOS + with ALL UTILITIES

35-track $69.95

40-track $79.95

TRS-80TM DISK AND OTHER MYSTERIES

. . .$19.95

MICROSOFT tm BASIC DECODED & OTHER MYSTERIESfortheTRS-80TM $29.95

'RINGS' & THINGS

Help prevent data loss and media damage due to improper diskette centering and rotation with the FLOPPY SAVER™ reinforcing hub ring kit. 7-mil mylar rings install in seconds. Kit is complete with centering tool, pressure ring, 25 adhesive backed hub rings and instructions. HUB RING KIT for 51/," diskettes .. $9.95 REFILLS(50Hub Rings) $4.95

Protect your expensive disk drives and your valuable diskettes with our diskette drive head cleaning kit. The kit, consisting of a pair of special "diskettes", cleaning solution and instructions, can be used for 52 cleanings. Removes contamination from recording surfaces in seconds without harming drives.

CLEANING KIT for b'A" drives

$24.95

Single Sided, Single Density, Soft-Sectored 5%-inch, (for TRS-80™) Mini-floppy

DISKETTES $21

95

box of 10

These are factory fresh, absolutely first quality (no seconds!) mini-floppies. They are complete with envelopes, labels and writeprotect tabs in a shrink-wrapped box.

TM

PLAIN JANE

DISKETTES

The Beautiful Floppy

with the Magnetic Personality™

Thousands of people have switched to this low-cost alternative. These quality diskettes are packaged in a plain white box ... no fan cy printing, fancy names or fancy labels, not even our own (labels cost money). Trust us

PLAIN JANE™ Diskettes $21.95

10 boxes of 10 . . (eachbox)$21.50

VERBATIM'S PREMIUM DISKETTES AT AFFORDABLE PRICES

DATALIFE

TM

Seven data-shielding improvements mean greater durability and longer data life. These individually certified diskettes feature thicker oxide coating, longer-lasting lubricant, improved liner, superior polishing and more! Meets or exceeds IBM, Shugart, ANSI, ECMA and ISO standards. Buy the best ... buy DATALIFE™. VERBATIM DATALIFE™ DISKETTES 5%-inch (box of 10)

MD525-01 $26.95

10 boxes of 10 . (each box)$25.95 8-inch FLOPPIES

Single-Density, FD34-1000. . $29.95 Double-Density, FD34-8000 . . $39.95

CALL FOR INFORMATION ON OTHER TRS-80™ PRODUCTS

Products damaged in

transit will be

exchanged.

Prices, Specifications,

and Offerings subject

to change without

notice.

MOST ORDERS

SHIPPED

WITHIN ONE

BUSINESS DAY

PRICES IN EFFECT

February 1, 1980 THRU

February 28, 1980

WE ACCEPT

• VISA

• MASTER CHARGE

• CHECKS

• MONEY ORDERS

• C.O.D.

• Add $2.50 for standard UPS shipping & handling

• $2.00 EXTRA for COD.

• Ohio residents

add 5'/2% sales tax.

TO PLACE ORDER 1-800-321-3552

CALL

TOLL FREE

IN OHIO call (216)289-7500 (COLLECT)

FOR PRODUCT INFO 1-800-321-3640

(YlETfl TECH&O.QBES C[]RP[]Rfli™

26111 Brush Avenue. Euclid. Ohio 44132

801215

TRS-80 is a TM of Tandy Corp. PLAIN JANE is a TM ot MTC. 31980 by Metatechnologies Corporation. Inc.

Circle 249 on inquiry card.

BYTE February 1981 335

What's New?

SOFTWARE

Stock Portfolio Package

Stockpak combines Standard & Poor's expertise with the latest analytical methods of Wall Street investors to help users buy and sell stocks and to manage portfolios. Stockpak assists in evaluating and managing a portfolio of up to 100 securities, with as many as 30 transactions on each issue. Up to 900 New York and American Stock Exchange and over-thecounter common stocks can be analyzed. Users can record buy and sell transactions, price, dividend information, and stock

splits. Companies can also be analyzed. Designed for TRS-80 users, the four Stockpak floppy disks contain the portfoliomanagement system, screen and select system, a report writer system, and a demonstration data base. Stockpak is a creation of the Standard & Poor's Corporation, and it is available for S49.95 at Radio Shack outlets. An annual subscription to a monthly update service is available for S200.

Circle 400 on inquiry card

APEX-Apple II FloppyDisk Operating System

The APEX disk operating system features a command structure that is similar to CP/M's. Twenty command words are contained within the system, and APEX has the ability to treat external programs as transient commands to the operating system. There is a scrolling editor that is compatible with the Videx 80 character card. APEX can handle both 5and 8-inch floppy and hard disks on the same system, and it is fully functional on single-drive and multidrive systems. Backup files, a backup directory, read-afterwrite. and size limit checks are included. File allocation techniques make APEX's file handling four times faster than CP/M 's. Automatic default structures set up command strings, file names, and extensions. A special device handler structure allows for interfacing nonstandard peripherals. The basic APEX package includes a twopass resident assembler and a macro

editor. The assembler generates an alphabetized symbol table, a crossreference table, and it is capable of assembling over 1900 lines per minute. The editor has 18 commands and 10 text buffers. APEX costs S99 from Apparat Inc. 4401 S Tamarac Pky, Denver CO 80237, |303) 741-1778.

Circle 401 on inquiry card

TRS-80 Program Generator

The program Generate writes a threeprogram system (a selector, input/edit module, and print program) that will maintain a key file. The input/edit module allows the operator to add, delete, or change records and their keys in the file. The print program selects the fields to be printed, and it selects the range to appear on the listing. The program comes on a 5-inch floppy disk with instructions that include suggested applications. Generate requires a TRS-80 Model I Level II system with at least two disk drives and 32 K bytes of memory. A printer is optional, because the program can be user-adapted for a display screen. The program costs S100 from Paul Swanson, do DataWorks Inc. 97 Jackson St, Cambridge MA 02140, (617) 492-4305. Circle 402 on inquiry card

OSI Software

HEXDOS 2.3 is a disk operating system designed for use with OSI |Ohio Scientific] BASIC in ROM |read-only memory). Residing in 2 K bytes of memory, HEXDOS supports a real-time clock, named floppydisk files, trace and single-stepping of programs, a tone generator, multiple data files, editing capabilities, chaining of programs, and an interactive disassembler. The price for a 5-inch floppy disk and manual is S27.50.

FOCAL-65 is DEC'S [Digital Equipment Corporation) powerful, high-level language adapted for the 6502. It constructs programs that are more compact than similar BASIC programs. All in 8 K bytes, FOCAL-65 features 9-digit floating-point arithmetic and string handling functions. This language is available on a 5-inch floppy disk or cassette with a manual for S49.50. Information on either software package can be obtained by writing The 6502 Program Exchange, 2920 W Moana, Reno NV 89509.

Circle 403 on inquiry card

Where Do New Products Items Come From?

The information printed in the new products pages of BYTE is obtained from "new product" or "press release" copy sent by the promoters of new products. If in our judgment the information might be of interest to the personal computing experimenters and homebrewers who read BYTE, we print it in some form. We openly solicit releases and photos from manufacturers and suppliers to this marketplace. The information is printed more or less as a first-in first-out queue, subject to occasional priority modifications. While we would not knowingly print' untrue or inaccurate data, or data from unreliable companies, our capacity to evaluate the products and companies appearing in the "What's New?" feature is necessarily limited. We therefore cannot be responsible for product quality or company performance.

336 February 1981 © BYTE Publications Inc

What's New?

SOFTWARE

Statistics Program

Microstat is a statisticspackageforCP/M systems using BASIC-80. The program is chiefly oriented towards files. It includes a data-management subsystem that allows users to list, edit, destroy, delete, augment, sort, rank order, lag, move, merge, and transform data into new data. Programs are provided for statistical analysis in descriptive statistics, hypothesis testing, analysis of variance, scatterplots, correlation analysis, simple and multiple regression, time series, and more. Microstat requires 48 Kbytes of memory, a single-density 8-inch floppy-disk drive, and CP/M with BASIC-80. The program is available for the North Star disk operating system and BASIC; two disk drives are recommended. The cost is S250. A manual is S15. For further information, contact Ecosoft, POB 68602, Indianapolis IN 46268, |3I7| 283-8883.

Circle 404 on inquiry card

CP/M 2.2 for OSI C3 Systems

Known as CP/M2, this version of CP/M 2.2 is compatible with the original OSI [Ohio Scientific) C3 computer's CP/M format. All software and data on current OSI CP/M disks can be retained. With CP/M2, disk read operations are four to five times faster, and disk write operations can be as much as fifty times faster. The C3 CP/M2 compensates for 2 or 4 MHz microprocessor operation. The system also includes a CP/M disk-to-disk copy routine, a memory test program for the ZBO, and I/O (input/output) drivers for most OSI peripherals. CP/M2 is available for S200 from Lifeboat Associates, 1651 Third Ave, New York NY 10028. |212) 860-0300. Circle 405 on inquiry card

CP/Modem

Information Engineering has released CP/Modem. This package can send files between a CP/M computer and another computer, make a CP/M system function as a terminal to a remote computer, and allow users to operate, control, and perform diagnostics on remote CP/M systems. A high-level protocol supports error checking and automatic retries during file transfers. File transfer is block-oriented. CP/M modem has three operating modes: terminal, termecho, and datalink, plus a transitional state command mode. The program has a split-screen display, with status indicators for data rates, mode, parity, stop bits, word length, data type, and fjle name. The software supports data rates to 19.2 k bps and has full- and halfduplex modes. The CP/M Modem software package is distributed as object code on 5- and 8-inch floppy disks in CP/M format. A single microprocessor license is S300. The manual is S15. Mainframe support for Digital Equipment Corporation's DECsystem-IO'is SI 500. For further information, contact Information Engineering, 8 Bay Rd, POB 305, Newmarket NH 03857, [603) 659-5891. Circle 406 on inquiry card

muLISP/muSTAR-80 Al Development System

The muLISP-80 pseudocode LISP interpreter can provide the basis for Al (artificial intelligence) projects. muSTAR-80 provides a resident display-oriented editor and debugging facility. A pseudocode compiler in muLISP-80 produces extremely compact code. Dynamic allocation of data-space boundaries maximizes the use of programmable memory storage. Linkage to machine-language subroutines is easily performed. These two programs work on 8080-, 8085-, and Z80-based systems. The system includes a library file that contains utility functions which provide examples of muLISP function definitions. Supplied with the system are several games, including a muLISP implementation of the Eliza (Doctor) program. Microsoft and Lifeboat Associates are offering muLISP/muSTAR-80 for a variety of microcomputers including those using the TRSDOS and CP/M operating systems, or equivalent systems. For details, contact Microsoft, 10800 NE 8th, Suite 819, Bellevue WA 98004, or Lifeboat Associates, 1651 Third Ave, New York NY 10028. Circle 407 on inquiry card

CP/M-86

Digital Research's CP/M-86 operating system is for any microcomputer that is based upon the Intel 8086/8088 microprocessors. CP/M-86 is a single-user operating system designed to take advantage of the 8086's address space and speed, while expanding upon the facilities of CP/M. For compatibility, the file format of CP/M 2 has

been retained. CP/M-86 can function as a slave node in a CP/NET network. Logical and hardware-dependent portions of the operating system are modularized. For more information, write to Harold Elgie. c/o Digital Research, POB 579, 801 Lighthouse Ave, Pacific Grove CA 93950, (408) 649-3896.

Circle 408 on inquiry card

February 1981 © BYTE Publications Inc 337

What's New?

SOFTWARE

VisiCalc Plus for the HP-85 Microcomputer

VisiCalc Plus is an enhancement of the calculating and bookkeeping VisiCalc program for the Hewlett-Packard HP-85 microcomputer. The program is useful for forecasting, budgeting, and other business and technical applications. The enhancements include a graphics program that lets users turn VisiCalc tables into four-color graphics. Line charts, bar charts, pie charts, and curve-fitting graphs are available along with graphics features, such as six styles of lines and hatchings. Twenty extra financial, statistical, and mathematics functions include internal rate of return, standard deviation, and variance. A "Help" facility displays information about a keyword typed by the user. VisiCalc Plus comes on tape cartridges and floppy disks for S200. A 16 K-byte memory module is required to run the program. For information, contact Inquiries Manager, Hewlett-Packard Company, 1507 Page Mill Rd, Palo Alto CA 94304, (4-15) 857-1501.

Circle 409 on inquiry card

TRS-80 Cash Register Software

Computer Consultants', 312 Hoyt St, Dunkirk NY 14048, (7 76) 366-0766, TRSPOS allows a TRS-80 Level II to function as a point-of-sale terminal system. Some TRSPOS features are its English operator prompting and error messages and an electronic memo pad. With TRS-POS, the businessperson can keep track of sales commissions and inventory. The system can be user-configured to suit individual needs. The TRS-POS system comes in a 16 K-byte package that allows 50 userdefinable departments and in a 32 K-byte package that allows I 10 departments. TRS-POS prices begin at S100.

Circle 410 on inquiry card

The Store Manager

High Technology Inc. 8001 N Classen Blvd. POB 14665, Oklahoma City OK 73113, (405) 840-9900, is distributing The Store Manager. This program is a point-ofsale and inventoiy-control system. It produces purchase orders, receiving reports, invoices, packing slips, and quotations. Sales totals and inventory-management reports are also handled. The program is useful for managing small businesses. The Store Manager runs on a 48 K-byte Apple II with at least two floppy-disk drives. The suggested retail price is S250.

Circle 411 on inquiry card

Pascal Express Utility Package

This package of utilities and other software for the Apple II is designed to help experienced BASIC users become acquainted with UCSD Pascal. Four sections simplify I/O (input/output) formatting," allow access and change in the disk directory from a Pascal program; perform integer, string, and real number conversions; and support files of variable-length records. Also included are Pascal demonstrations with listings on BASIC equivalents, a routine to view disk files in ASCII or hexadecimal code, a text formatter, a program to maintain a variablelength data file, and a Happy Birthday surprise. A manual, a disk, and the sourcecode files cost 545 from Software Express, POB 50453, Palo Alto CA 94303, |4I5) 856-9244.

Circle 412 on inquiry card

Multi-User, Multitasking Disk Operating System

The Cromix operating system supports Cromemco's floppy- and hard-disk drives. It includes multiple hierarchical directories • and subdirectories; compatible I/O (input/ output), which supports- user redirection of I/O; a shell-sort program; a password security system," data and time support; file buffers; and swapping-free execution of tasks through bank selection. The Cromix operating system includes a CDOS Simulator that allows CDOS programs to be executed directly. Cromix requires a minimum memory of 128 K bytes. A single 64 K-byte memory card must be added for each additional user or task. Cromix is available on 5- or 8-inch floppy disks for S295. Inquiries can be addressed to Cromemco Inc. 2B0 Bernardo Ave, Mountain View CA 94043, |4l5) 964-7400.

Circle 413 on inquiry card

The Prisoner

The Prisoner was inspired by the television series of the 1960s. Consisting of twenty interlinked games, the program places the player on an island housing a psychological prison camp. The player's task is to escape both the island and its attempts to extract information from him. The Prisoner requires an Apple computer with 48 K bytes and a single disk drive. The program lists for S 29.95. Contact EduWare Services Inc, 22035 Burbank Blvd. #223, Woodland Hills CA 91367, [213) 346-6783.

Circle 414 on inquiry card

Track Orders Daily

CORP is a customer-order review program for a salesperson in any small- to medium-sized business. Designed with the TRS-80 Models I and II in mind, CORP tracks the daily orders of individual salespersons. CORP allows management personnel to monitor a salesman's performance and to know which customers have not placed an order since any particular date. Different criteria for selecting reports on customer orders can be specified. CORP contains updating facilities and diagnostics. It is available on a 5-inch floppy disk, including documentation, for S195 from B & B Software, POB 2090, Ann Arbor Ml 48106.

Circle 415 on inquiry card

Apple II Word Processor

Computer Solutions, 6 Maize PI. Mansfield, Queensland 4122, Australia, has announced its word-processor software for the Apple II. The software allows true uppercase and lowercase on the Apple. Full "mailmerge" facilities are included in the system. The software and manual are priced at S295.

Circle 416 on inquiry card

TFORTH

TFORTH is a procedural language that specifies process rather than desired result. It produces a compact code that can be executed at high speeds. TFORTH uses a stack for parameters and a dictionary for words that allows new words to be created in terms of predefined words. New data types and new processes can become part of the language. TFORTH can be used to develop new languages, provide simple control of devices, and implement tasks requiring monitoring and decision. Certain hardware modifications can be eliminated by using TFORTH to do digital logic or data reduction. TFORTH is designed for the TRS-80 with 16 K bytes of programmable memory and a single floppy-disk drive using either TRS-DOS or NEWDOS. It costs SI 29.95 or S 136.95. depending on additions. Contact Sirius Systems, 7528 Oak Ridge Hwy, Knoxville TN 37921, |615) 693-6583.

Circle 417 on inquiry card

338 February 1981 © BYTE Publications Inc

What's New?

PUBLICATIONS and MISCELLANEOUS

Sinclair ZX80 Users Magazine

Sync is a bimonthly magazine for users of the Sinclair ZX80 microcomputer. The publication carries articles about how best to use the features of the ZX80. Sync also carries financial analysis, statistics, simulations, and games. Sync has published program listings for Acey Ducey, Hurkle, and the Nicomachus "boomerang" puzzle. Reviews of software, peripherals, and books related to the ZX80 are also provided. Subscriptions are S10 per year from Sync, 39 E Hanover Ave, Morris Plains NJ 07950, (201) 540-0445.

Circle 418 on inquiry card

Educational Catalog

Marck publishes a free mail-order educational software catalog that has descriptions of hundreds of programs for small computers. Related products and articles are also included. Contact Marck, 280 Linden Ave, Branford CT 06405, |203| 481-3271.

Circle 419 on inquiry card

Article Index

Magdex Research has announced a quarterly publication entitled The Article Index. The Index covers many articles, short notes, and other information contained in the top ten microcomputingjournals. The Index is divided into two sections. The first section categorically lists all article titles and short paragraph locations. The second lists references by keyword. In all. The Index has over I 1.000 references. Subscription rates are S7.50 for one year, S 13.50 for two, S l8forthree, and lifetime rates are S45. Charter subscribers receive indexes for 1977 thru 1980. Contact Magdex Research, POB 706, North Plains OR 97133.

Circle 420 on inquiry card

PGI Wholesale Publishes Price Card

PGI Wholesale has published a quickreference price list. The guide contains pricing information on microcomputer products from more than thirty-five manufacturers, including the Archives Business Computer. Contact PGI Wholesale, 1425 W 12th PI, TempeAZ 85281, (800) 528-1415 or (800) 528-6450.

Circle 421 on inquiry card

Design Aids for Electronics

This catalog has been designed for engineers and draftsmen in the electronics industry. It features templates containing the latest in logic and schematic symbology and component layout patterns. All symbols or patterns comply with ANSI, IEEE, IPC, and MIL-STD specifications. The catalog is available from Tangent Template Inc. POB 20704, San Diego CA 92 I 20, (714) 292-0046.

Circle 422 on inquiry card

Continuous Forms

Discount Data Forms Inc. 407 Eisenhower l_n S. Lombard IL 60I48, (312) 629-6850, is marketing a line of continuous computer forms. The product line includes stock invoices, statements, bills of lading, purchase orders, and voucher, payroll, and personal checks. A brochure and samples are available from the company free of charge.

Circle 423 on inquiry card

Word Processing Report

The Small Systems Group has begun publication of a series of product evaluation reports. The first report "Word Processing on Personal Computers," is now available. This report introduces word processing with sections on software, hardware, and applications. It describes Auto Scribe, Electric Pencil, Magic Wand, and WordStar word-processing programs. Single copies of the report are available for S10 from the Small Systems Group, POB 5429, Santa Monica CA 90405. (213)

392-1234. Circle 424 on inquiry card

Education Catalog

The Micro Software Division of Charles Mann & Associates has compiled the Education Catalog. This catalog details educational programs for the Apple II, TRS-80, and Tl 99/4 microcomputers. The programs can be used to develop customized teaching programs, to teach BASIC programming, and to reduce administrative tasks. Grade reporting, class scheduling, and record-keeping programs are also described. These and other programs have been designed by Charles Mann & Associates, which is located at 7594 San Remo Trl, Yucca Valley CA 92284, (714) 365-9718.

Circle 425 on inquiry card

Dual-Purpose Computer Checks from NEBS

The 9022 computer checks are designed to be used for payroll or accounts payable. The stub portion is blank except for the customer's name and the consecutive check number. The forms are available in quantities as low as 500 for S29.95. Prices include printing the customer's name and address, bank name and number, consecutive numbering, and inclusion of an MICR code line. Contact NEBS Computer Forms, 78 Hollis St, Groton MA 01450, (800) 225-9550, in Massachusetts (800) 922-8560. Circle 426 on inquiry card

Speech Synthesis Evaluation Board

An assembled circuit board for evaluating the operation and application of the Digitalker speech synthesis integrated-circuit set is available from National Semiconductor Corporation, 2900 Semiconductor Dr, Santa Clara CA 95051, (408) 737-5000. The DTI000 board requires a single 9 V power supply and a speaker for operation. It contains National Semiconductor's speech processor circuit, two speech ROMs (read-only memories), output filter, audio amplifier, keyboard, a microcontroller, and an EPROM (erasable programmable read-only memory). The speech ROMs enable users to link words consisting of numbers and letters, nouns, verbs, tones, and silence durations into phrases and sentences. National Semiconductor's Digitalker speech-synthesis systems utilize human speech and voice waveforms for digital encoding and storage. The DT1000 is available for S495.

Circle 427 on inquiry card

February 1981 © BYTE Publications lnc 339

What's New?

PERIPHERALS

Enhanced AIO Board from SSM

The SSM AIO serial and parallel Apple II interface board has been enhanced. The AIO now interfaces with serial and parallel devices simultaneously under Pascal. The RS-232 serial interface has three handshaking lines and eight data rates from I 10 to 9600 bps (bits per second). Additional data rates are possible through external input. Two bidirectional 8-bit parallel ports are provided with four additional interrupt and handshaking lines, as well as interface configurations that are progammable and software controlled. The AIO includes firmware for controlling serial interface and software for driving parallel printers. It includes the cable assemblies necessary for parallel and serial interfaces, and a user's manual. Contact SSM Microcomputer Products, 2190 Paragon Dr, San Jose CA 95131, (408)

946-7400. Circle 433 on inquiry card

PET Graphic Interface Board

The MTU K-1008-6 PET Graphic Interface adds high-resolution graphics to the PET computer. The expansion board features five ROM (read-only memory) sockets that can be set at the same or different addresses with software control of whichever sockets are enabled. The board provides user control over a matrix of 64,000 dots. The device serves as an 8 K-byte expansion memory when not used for graphics. On-board expansion allows use with an optional light pen. Graphics software is also offered. The board is priced at S320; connectors for older model PETs are S35; and connectors for the newer model PETs are S59. For more information, contact Micro Technology Unltd, 2806 Hillsborough St, POB 12106, Raleigh NC 27605, (919) 833-1458. Circle 434 on inquiry card

MPI's Model 88G Printer

The Model 88G impact matrix printer features 100 cps (character per second) bidirectional or unidirectional printing, with throughput rates of up to 150 lines per minute. A full uppercase and lowercase 96-character ASCII (American Standard Code for Information Interchange) set is printed in a 7 by 7 matrix, with print line formats of 80, 96, or 132 columns per line over an 8-inch print area. Doublewidth characters are software-selectable in any of the font styles or character densities. A high-resolution, dot-addressable graphics option can be added for plotting, printing of screen graphics, drawing of illustrations, or producing special characters and identification marks. Forms handling is carried out with a paper-feed system that can accept fanfold forms from 1 to 9/2 inches in width. Sixteen selectable form lengths and a "skip-over-perf" feature are provided. The printer uses continuous-loop ribbon cartridges, and it has an RS-232C, and a parallel interface. It can also be interfaced to devices with an IEEE-488 bus output. A detachable roll paper holder, single-sheet feeder, and a 2 K-byte buffer are available. The Model 88G with the graphics option lists for S799. Contact MPI, 2099 W 2200 South, Salt Lake City UT 841 19, (801) 973-6053. Circle 432 on inquiry card

Turn the TRS-80 into a Time-Sharing Terminal

TERMCOM is a hardware and software package that turns the TRS-80 into a timesharing terminal. TERMCOM hardware allows Level II users to utilize time-sharing systems without acquiring the Expansion Interface and RS-232 board. The software includes full paging capabilities, making it possible to store several screens of data, which are accessible at any time. The TERMCOM program allows lines to be scrolled off the screen while still remaining accessible in memory. The wrap-on-blank capability breaks long lines into two lines between words. For tabular materials, automatic left- or right-justification may be specified. The TERMCOM package can lock information on the top or bottom of the screen, while keeping the other portion free for normal use. Other features include memory buffer-overflow protection, uploading and downloading of files from disk, and variable rates for file loading to match other systems used in time-sharing. It is compatible with all Radio Shack supplied products. The package costs S 169.95 from Statcom Corporation, 5758 Balcones Dr, Suite 202, Austin TX 78731, (512) 451-0221. Circle 435 on inquiry card

340 February 1981 © BYTE Publications Inc

What's New?

SYSTEMS

System Zero from Cromemco

Cromemco's System Zero computer, an S-100 bus microcomputer, includes a Z80A-based single-card computer, I K bytes of programmble memory, 3 K bytes of Control BASIC in ROM (read-only memory|, and three extra slots on the S-100 bus. The system is designed for ROM programs, but it can be expanded by adding memory and I/O cards. The System Zero/D is available with floppy-disk drives, the Z80A board, 64 K bytes of programmable memory, and a disk-controller card. The controller contains RDOS-2, a disk operating system that reads and writes single- and double-sided and single- and double-density floppy disks, and also contains a systems diagnostic routine. Software for the System Zero includes RPG II, FORTRAN, COBOL, 16 and 32 K Structured BASIC, LISP, word-processing, database management, business software, and operating systems. The System Zero list price is S 995, and the Zero/D has a list price of S2995. The Model DDF dual-disk drive is available for S1295. Contact Cromemco Inc. 280 Bernardo Ave, Mountain View CA 94043, (4 1 5) 964-7400. Circle 429 on inquiry card

Microcomputers with

High-Resolution

Graphics Options

The Dynamic Blackboard microcomputer systems use the S-100 bus and a Z80A microprocessor. The systems support either black-and-white, gray shades, or full-color graphics at a resolution of 640 by 5 12 pixels. CP/M-compatible graphics software and Tektronix-emulation software are also available. Graphics printers are supported. Three Dynamic Blackboard systems are available: the Brilliant Terminal, the Standalone System, and the Network Configuration. The Brilliant Terminal is for larger mainframes, and it can be used as a stand-alone computer and color graphics terminal. The Standalone System has a graphics option, and the Network Configuration allows several microcomputers to share a disk subsystem and a printer. Prices for the single computers are in the S 10,000 to S 15,000 range. For more information, contact the Cambridge Development Laboratory, 36 Pleasant St, Watertown MA 02172, (617| 926-0869.

Circle 430 on inquiry card

SSM's Z80 Microprocessor Board

SSM Microcomputer Products, 2190 Paragon Dr. San Jose CA 95131, (408) 946-7400, has announced the CB2 Z80 microprocessor board. The CB2 is capable of operating at 2 or 4 MHz, and it includes sockets for two 2716 or 2732 EPROMs (erasable programmable read-only memories] or HM6I 16 2 K-byte programmable memories. The memory sockets can be enabled or disabled. Run/stop and single/ step switches are also included on the board to permit system evaluation without the need for a front panel.

The CB2 also features a firmware-vector jump and an output port to control eight extended address lines. Memory can be expanded to more than 64 K bytes. Board jumpers can generate the proposed IEEE (Institute of Electrical and Electronics Engineers) S-100 signals. The board can emulate 8080 I/O (input/output) addressing, and it is provided with an 8-bit output port for extended addressing. The CB2 requires + 8 V at 0.75 A.

Circle 431 on inquiry card

A MAJOR NEW YORK BANK INVITES YOU TO BANK AT HOME

Our

acc<

Sof Thi thi

By Personal Computer

stem talks with yours

ess to the bank for! bill pavi rig account transfers balance inquiry record keeping

tware requires 4SK bytes of

s is a pilot

s message by

A program diskette provides

memory and one

program. For more information, sending in the f orm be1ow.

d i s k d rive, please terminate

NAME

ADDRESS ; CIT Y_

.STATE ZIP.

TELEPHONE NO

Name and type of system

Do you have communications capability?-. If not> are you planning for it?

MAIL FORM TO: Home Banking System P.O. Box 721 Radio City Station ---_ New York, New York 10101

February 1981 © BYTE Publications Inc 341

What's New?

PERIPHERALS

Ampex's Video Terminal

Ampex Corporation, 200 N Nash St, El SegundoCA 90245, |2I3) 640-0150, has entered the video-terminal market with the Ampex Dialogue 80, a buffered editing terminal that operates in conversational or block modes. The terminal features a detached keyboard, lowercase descenders, and a 25th display line that allows operators to determine the status of various operational modes and note errors. Dialogue 80 has an RS-232C asynchronous interface that operates at half- or full-duplex and a standard serial printer interface. Scrolling is a standard feature in the conversational mode. The display features 24 lines by 80 characters. The format is a 6 by 8 dot matrix in a 7 by 10 field. The terminal has reverse video, blink.

blank, underline, and half-intensity features. Protected fields appear at halfintensity and cannot be changed when in the protect mode. Editing features include erase, insert, and delete character and line functions. The 128 symbols include 96 ASCII (American Standard Code for Information Interchange) characters, 2 1 control characters, and 11 characters to support line drawings. Constants, screen formats, or command sequences for the terminal and host computer are user-programmable. A 2 K-byte expansion memory is optional. The Dialogue 80 is SI 149 in single units.

Circle 436 on inquiry card

Portable Bar-Code Reader

The Model 9400 bar-code reader is designed for in-house data collection. A bar-code alphanumeric keypad is provided for manual data entry. Bar-code labels up to 32 characters long may be scanned. The memory has a 20 K-byte capacity. The user may select between a belt clip and a shoulder strap to carry the unit. The 9400 may be operated on-line in the terminal mode without affecting data in its memory, and a real-time clock feature is available to store time and date information. Previously stored data can be reviewed and edited. The Model 9401 Charger/Interface unit provides two RS232C connectors. Contact Wade T Nixdorff at Interface Mechanisms Inc. POB N, Lynnwood WA 98036, (206) 743-7036.

Circle 437 on inquiry card

Info 2000s Performer Systems

The Performer Systems are an entire line of business microcomputers offering word processing, billing, general accounting, data communications, and recordkeeping functions. One model, the Standard Performer, uses 5-inch floppy-disk drives that store 400 K bytes of memory |about 200 typewritten pages). Another model, the Maxi Performer, uses 8-inch drives that can hold 1.25 megabytes |about 600 typewritten pages). As a word processor, either Performer can handle

documents such as contracts, engineering reports, and ordinary business correspondence. Functions include true proportional spacing, underlining, boldface, justification, centering, indentation, and more. Typical applications include inventory, purchase or sales orders, court or appointment calendars, and customer or prospective customer lists. Additionally, mailing labels and envelopes can be prepared. Facilities include complex sort sequences and selection criteria, fullformula arithmetic, and multilevel subtotals and page breaks. Accounting capabilities include accounts receivable,

accounts payable, general ledger, and financial statement preparation. A clientbilling package for attorneys, accountants, consultants, and other professionals is available. The Performer also supports the WESTLAW automated legalresearch system and the New York Times INFOBANK services. The systems are priced between SI2,00 and SI8,000, or they may be leased for S400 to S600 per month. Contact Info 2000 Corporation, 20620 S Leapwood Ave, Carson CA 90746, |2I3) 532-1702.

Circle 438 on inquiry card

342 February 1981 © BYTE Publications Inc

What's New?

PERIPHERALS

On-Board Screen Memory with the V-100 Video Controller

The V-100 video-controller board, with 2 K bytes of on-board screen memory, can reduce central-processor overhead. It is fully compatible with the IEEE's (Institueof Electrical and Electronics Engineers) S-100 bus standard. The V-100 can be I/O (input/output) mapped, so that the screen memory does not take up space in the user's system. Interfacing to the video monitor is handled by writing control information to the V-100's logic. The board can display 24 lines by 80 characters in 7 by 9 dot-matrix formats. Fonts are available for standard ASCII (American Standard Code for Information Interchange), or French, German, or Japanese char

acters. It also provides 16 user-programmable graphic characters. The board can accept data at 2 megabytes per second, allowing data to be transferred to the screen at the processor speed. A compatible software package, VEDIT, allows screen editing with full cursor control, block moves, file handling, and more. It requires a CP/M-compatible operating system. The V-100 is priced at S450 per board, and VEDIT is SI 10. Contact Piiceon Inc. OEM Division, 2350 Bering Dr, San Jose CA 951 12. CompuView Products Inc. the maker of VEDIT, is located at 1531 Jones Dr. Ann Arbor Ml

48107. Circle 439 on inquiry card

TRS-80 Printer

and Memory

Expansion Module

This printer/memory expansion module can add 16 K or 32 K bytes of dynamic programmable memory to a TRS-80 microcomputer. It can also drive Microtek's MT80P dot-matrix printer or any Centronicscompatible printer. The module is housed in an aluminum case that sits under the video display. It is available in three configurations: the MT-32A, without memoiy for S99.50; the MT-32B, with 16 K bytes of programmable memory for S159.50; or the MT-32C with 32 K bytes of memory for S 199.50. For further information, contact Microtek Inc. 9514 Chesapeake Dr, San Diego CA 92123, (800) 841 -1081. in California (714) 278-0630. Circle 440 on inquiry card

High-Resolution H-8 Color Graphics

The Heathkit H-8 is now able to generate high-resolution color graphics with the addition of this color graphics board. The board is fully compatible with the H-8. It contains 8 K bytes of static programmable memoiy, which is address dipswitch selectable. On-board RF (radio frequency) modulation is included for output to color or black-and-white television. The board can generate eight graphic display modes, eight colors, and features a resolution of 256 by 192 pixels. It is available in kit form for S379, or assembled and tested for S479. Request complete details from Owen Phairis Computer Products, POB 3400, Big Bear Lake CA 92315, (714) 585-8354.

Circle 441 on inquiry card

Apple Plug-Compatible Floppy-Disk Drive

The A-70 and A-40 floppy-disk drives have a jumper-selectable boot PROM (programmable read-only memory) for 13- or 16-sector Integer BASIC- or Pascal-language cards as standard features. The A-40 drive provides 40 tracks of storage and track-to-track speeds of 5 ms for S495 for the first unit and S395 for additional units. The A-70 has the same features as the A-40; however, it provides 70 tracks of storage and is priced at S675 for the first unit and S575 for additional units. For more information, contact Micro-Sci, 1405 E Chapman, Suite E, Orange CA 92666, (7 1 4) 997-9260. Circle 442 on inquiry card

Power Supply on a Card

An 8 W power supply has been introduced by Miller Technology, 16930 Sheldon Rd, Los Gatos CA 95030, (408) 395-2999. The PS-80 supplies + 5 V at 800 mA, + 12 V at 150 mA, and - 5 and - 12 V at 150 mA. The power supply card is 11.5 by 16.5 cm (4/2 by 6/2 inches), including the 22-pin edge connector. A standard fuse is supplied. A 115V AC and a power-line switch can be connected with the supplied connectors. The PS-80 is available in kit form for S35 or assembled and tested for S60.

Circle 443 on inquiry card

PS-8 Power Supply

Cromemco's PS-8 power supply is designed to power microcomputer systems configured with the Cromemco CC-8 eight-slot card cage and any combination of S-100 boards. The PS-8 provides one output of +7.5V/12A, + 14.5V/2.5A, and -14.5V/1.0A. A system reset switch is built into the power supply. The supply is designed for 110 or 220 V operation. Ambient temperature operation is from 0 to 55° C. The power supply is available from Cromemco Inc. 280 Bernardo Ave, Mountain View CA 94043, (415) 964-7400. Circle 444 on inquiry card

February 1981 © BYTE Publications Inc 343

What's New?

PERIPHERALS

Bar-Code Reader for the Apple

The ABT BarWand plugs into the Apple II or III and reads standard bar code. ABT has also developed a program to read UPC (Universal Product Code). Additional programs have also been created to print and read ABT's own LabelCode and Applesoft programs in Paperbyte Code. The latter two programs are forms of bar code that can be printed with a dot-matrix printer. When bar code is entered through the BarWand, a scan tone sounds indicating that the last line of data was correctly read. The suggested retail price of S195 includes the BarWand and a demonstration floppy disk of the UPC, LabelCode, and Paperbyte programs. A ROM (read-only memory) multiprotocol BarWand I/O (input/output) board is also available. For more information, contact Advanced Business Technology Inc. 12333 Saratoga-Sunnyvale Rd, Saratoga CA 95070, (408) 446-2013. Circle 445 on inquiry card

SSI Band Printer Has 900 Lines Per Minute

SSI's B-900 printer features several bands and a 48-, 64-, and 96-character set, plus specialized and foreign character sets. The print speed is 1 100 Ipm (lines per minute) at 48 characters, 900 Ipm at 64 characters, and 600 Ipm at 96 characters. Vertical spacing for multiple-form lengths, provisions for up to five copies, a diagnostic display, paper-out detect sensors, and print-to-bottom of the form capabilities are included. The B-900 is compatible with Digital Equipment Corporation's DECsystems 10 and 20. HewlettPackard, Data General, SEL, Texas Instruments, Burroughs, and other minicomputers and mainframes. Parallel interfacing is standard, and SSI also supplies serial synchronous and asynchronous interfaces. Contact Southern Systems Inc. 2841 Cypress Creek Rd, Ft Lauderdale FL 33309, (800) 327-5602, in Florida (305) 979-1000. Circle 446 on inquiry card

96 Tracks Per Inch 5-Inch Floppy-Disk Drives

The SA410 (single-sided) and the SA460 (double-sided) drives feature unformatted capacities of 500 K bytes and 1 megabyte, respectively, using double-density recording. For faster access time, the drives incorporate a helical cam v-groove lead screw for head positioning. The drives also use a DC spindle motor that allows the drive to be shut down when not in use. The drives can back up 5- to 10-megabyte hard disks, including Shugart's SA400 and 450 drives. Other features of the drives include a track-to

track access time of 6 ms, a tachometer that provides servo speed control, and an activity indicator. A maximum recording density of 5876 bits per inch is another feature. Mean time between failures is 8000 power-on hours. The SA410 costs S325 in OEM (original equipment manufacturer) quantities of 100; the SA460 is priced at S400 in the same quantities. For further details, contact Shugart Associates, 475 Oakmead Pky, Sunnyvale CA 94086, (408) 733-0100. Circle 447 on inquiry card

Apple II Nine-Voice Music Synthesizer

You can turn your microcomputer into a nine-voice music synthesizer with the AM-II package from Peripherals Plus. The AM-II package consists of the software and a board that plugs into the Apple II. The S198 AM-II allows users to compose music with two game paddles. The music is displayed as notes on a music staff. From a menu at the bottom of the screen, users can select notes from a six-octave range, along with duration and other characteristics. The music is displayed with graphic animation during playback. Using the keyboard, the user has control of key, tempo, envelope values and duration, waveform, and length. The AM-II is available from Peripherals Plus, 119 Maple Ave, Morristown NJ 07960, (800) 63 1 -81 1 2, in New Jersey [201) 267-4558.

Circle 448 on inquiry card

Link Winchester ST-506 Disk Drives to GPIB Computers

The MSC-9305 controller provides onboard interfacing to Seagate Technology's ST-506 disk drives, and incorporates the GPIB interface standard for attachment with computers using the GPIB standard bus. This will allow ST-506 drives to work with the PET, Xerox 13 50, and the Hewlett-Packard HP-85 system. It can also be used with computers accommodating GPIB adaptors, such as the Apple II, DEC (Digital Equipment Corporation) systems, Prolog, and with computers using Intel's Multibus. The controller employs an integrated data separator, automatic error correction, full-sector data buffer, and automatic position verification. The price of the MSC-9305 is S 700 from Microcomputer Systems Corporation, 432 Lakeside Dr, Sunnyvale CA 94086, |408) 733-4200. Circle 449 on inquiry card

344 February 1981 © BYTE Publications Inc

What's New?

PERIPHERALS

Touch-Input Video Display

The VuePoint touch-input terminal is 7 cm (2% inches) thick and has a 12-line by 40-character flat-panel display. VuePoint's controller provides for up to fifty-one pages of information. A response is sent to the host computer by finger contact to any one of 240 discrete touch-sensitive locations of the display screen. Communication is by selectable 300 to I 9,200 bps

(bits per second) data rates via an RS-232 interface. The controller for the display can be placed up to ten feet from the screen. Prices begin at S3500. For more information, contact General Digital Corporation, 700 Burnside Ave, East Hartford CT 06108, (203) 289-7398.

Circle 450 on inquiry card

Atari Memory

Expansion Kit Has

Supporting Software

This memory expansion kit will upgrade Atari 8 K-byte programmable memory boards to 16 K bytes. The kit provides five times more program space in highresolution graphics and allows access to

higher resolution graphics. The S79.95 price includes all hardware and instructions. Software support includes graphics programs like Plot & Draw, which generates graphics quickly while saving data for incorporation into BASIC programs. For more information, contact Mosaic Electronics, POB 748, Oregon City OR 97045, (503) 655-9574. Circle 451 on inquiry card

The Model 460 Paper Tiger Printer

The Model 460 printer has throughput speeds of up to I60cps (characters per second), can produce letter-quality print, and provides a variety of programmable print-control functions. The 460 employs a horizontal and vertical overlay dotmatrix character formation technique and a 9-wire bidirectional print head. Control functions include proportional spacing, bold text printing, and print densities of 10, 12, or 16.7 characters per inch. Automatic text justification, programmable horizontal and vertical tabbing, reverse paper feed, and positioning of characters to '/i20of an inch are other control features of the printer. It can print in 80-, 96-. and 132-column formats. Foreign or custom character sets can optionally be added to

or replace the standard ASCII (American Standard Code for Information Interchange) character set; the printer allows uppercase and lowercase characters with descenders. Forms control features include programmable top and bottom of form, perforation skip, and vertical and horizontal tabs. A microprocessor provides an automatic memory, electronics, and print capability test. A 2 K-byte bu fer and the ability to print graphics such as bar codes, block letters, and illustrations are included. The 460 has an RS-232C serial and a Centronics-compatible parallel interface. Data rates from 110 to 9600 bps are switch-selectable. The price for the Model 460 Paper Tiger printer is S1295 from Integral Data Systems Inc. Milford NH 03055, (603) 673-9100.

Circle 452 on inquiry card

Three HP-85 Interfaces

The three HP-85 interfaces are a serial (RS-232C-compatible) interface card, a general-purpose parallel I/O (input/output), and a BCD (binary-coded decimal) card. The serial-interface card provides the HP-85 with bit-serial asynchronous data communication capability, with support for RS-232C and current loop operations. Features include: user-programmable data rates, parity, bits per character, and stop bits without changing physical switch settings. Other features include full-duplex with I/O buffers, and a 20 mA current loop. This card allows printers, modems, and other peripherals to be used with the HP-85.

The general-purpose interface card provides bit-parallel byte- and word-oriented interfacing. Two bidirectional ports and two output-only ports are on the card. The card can be configured as four separate 8-bit ports, two 16-bit ports, or two 8-bit and one 16-bit ports. Paper-tape readers, punchers, and card readers can be interfaced with this card.

The BCD card permits all data to be present simultaneously on a set of 48 wires. Instruments can output up to eleven BCD digits; two BCD instruments can be accommodated with the card. Typical applications for this card are in voltmeters, counters, medical equipment, and electronic scales. The serial-interface card is S395 and the other cards are S495. Contact the Inquiries Manager, HewlettPackard Company, 1507 Page Mill Rd, Palo Alto CA 94304, (415) 857-1501.

Circle 453 on inquiry card

6800/6809 I/O Boards by Gimix

The Gimix 2-port serial I/O board has two independent RS-232-compatible I/O ports, with handshaking, on a 30-pin board. It features programmable pinouts and independent data rate and interrupt jumpers for each port. The board is compatible with the SS-50 and SS-50C bus configurations. The 2-port board, less cables, is priced at S 128.43.

Also available is an 8-port serial I/O board that boasts eight independent RS232-compatible I/O ports with handshaking—all on a 50-pin board. It features DIP-switch selectable data rates for each port, extended address decoding for the SS-50C bus, and selectable interrupts. An on-board data-rate generator permits rates of up to 38.4 k bps. This board costs S3I8.46, less cables. Complete details are available from Gimix Inc, 1337 W 37th PI, Chicago IL 60609, (3 I 2) 927-5 510.

Circle 454 on inquiry card

February 1981 © BYTE Publications Inc 345

Circle 250 on inquiry card.

Pw

LCD Digital Multimeter

Model WD-747

Large 3% digit 0.5" LCD readout. Side switches for easy one-hand use.

Accuracy better than 0.8% DCV. Resolution down to 10CVV, 100/xA DC, 0.1H.

Only DMM with built-in socket tor transistor hF£ testing. 10MS1 input impedance, 10 amp DC range.

Auto zero polarity. Full overloadprotection.

All functions color coded. Rugged orange-colored ABS plastic case.

Complete with battery, deluxe test probes and spare fuse.

Power Supplies

WP-29 Monitor Isotap

• Supply line: 105 to 130V, 48 to 500Hz • Isolated output: 0 to 150V 48 to 500Hz • Leakage: Less than 0.1 mA • Power rating (resistive load): 400VA • Meter: Taut band 3Vz" ±2% • Size: 3%" x 8V4" x 8%' • Weight: 14'/2 lb. • Comes with output cable.

WP-708 Triple Output

Two 0-20 VDC supplies, 0-2A full load. May be used in series to provide 0-40 VDC, 0-2A . One 5 VDC (0.4A full load) fixed supply. Two digital voltmeters 0-99.9 VDC with separate inputs on the front panel.

«

Order with Confidence and get the Fordham Advantage!

§

Uaii tot

our prices TOLL FREE

(800)645-9518

1» ' in NY. Slale call (516)752-0050

FORDHAM

855 Conklin St. Farmingdale, N.Y. 11735

■ Master Charge

■ BankAmericard

■ VISA ■ COD

■ Money Order

■ Check COD's extra

S

CEnTRonms

AUTHORIZED DISTRIBUTOR

VR Data, an international distributor of brand name hardware and peripherals to both business and personal users, has been a leader in sales and service since 1972.

The Centronics line of dot-matrix and correspondence quality printers is known world-wide for its high quality and exceptional reliability.

Centronics printers are designed for heavy use while their reasonable price makes them the obvious choice for even small applications.

Centronics offers a wide range of printers to satisfy even the most demanding applications.

Call VR Data today.

Toll Free (1) 800-345-8102 In Pennsylvania (215) 461-5300

WE SERVICE MANY BRANDS OF COMPUTER EQUIPMENT.

CALL FOR CONSULATION AND ESTIMATE.

DEALER INQUIRES INVITED • BIDS ACCEPTED 777 HENDERSON BLVD. FOLCROFT, PA 19032 ORDER NOW • TOLL FREE 1 (800) 345-8102 • IN PENNSYLVANIA (215) 461-5300

346 BYTE February 1981

Circle 251 on inquiry card.

vc/t

ELECTRONICS

INTEGRATED CIRCUITS

P.O. Box4430X Santa Clara, CA 95054

Will calls: 2322 Walsh Ave. (408) 988-1640 TWX 910-338-2139 Same day shipment. First line parts only. Factory tested. Guaranteed money back. Quality IC's and other componentsatfactory prices.

7-llON

7J8SN ?J9Qt,

7-I93N 7«5N 74IQ0N 7J107N

74J67N

74LS00 Til

7«.S0DK

74L502N

74LS04N

7JLS05N

7JLS0BP.

7JL510N

7JLS13N

74LS1JM

74LS2DN

7JLS2iN

74L528H

7JIS3CN

7JLS33N

741S3BN

74LS74N

74LS75N

74LS90fl

74LS93N

74LS9SM

74LS107N

74LS1l?M

MLSIIJr,

74LSl3!h

74LSI3EN

7JLSI5IN

7USIS5M

74LSI57M

74LSI62N

74LS163N

LINEAR CA30-S5 CA3046 CA3C61

LM30IAN.AH

LMTC5H

LM307N

LM3D8N

LM3D9K

LMIllMfJ

LM3I7

LM320K-5 LM32CK12 LM370K-I5 LM3201-5 LM320T4 LM3201-12 LM320M5

LM340K-5

LM3J0K-B

LM340K-12

LMJ4W-1S

LM340KJ4

LM34C1-S

LM340T 8

LM340T 12

LM3401-15

LM34C1 18

LM340T 24

LM35D

LM377

LM379

LM380N

LM3BI

LM3H2

IM70SH

LM723HN

LM733H

LM74ICH

LM74IN

LM747H K

LM748N

LMI303N

LM3905

LM3W9JI

MCMSBV

NE550H

HI555V

NE5SGA

NE565A

N1566V

NES67V

NE570B

781.05

781.08

78M05

75108

7549ICN

75492CN

754940

8700CJ 870ICN ; 87S0CJ LD130 9400CJV F ICL7I03

C0400I CD-JQ02 COiOC6 CD4O07 CD4O08 C04D0.9 CDJ0I0

CD40I6 CQ40I7 CD4018 CC4019 CO4C20 CD.4Q2I CD4022 CD4023 CD4024 CD4C25

CD4Q26 CD4027 C04028 CD4029 CD4030 CD4035

rpjcjc

CD4042 I CD 4043 i CD4014 < CD404G CD4049 CO4D50 , CD4051 . CO40E0 i CD 4066 i CD406B i CD4C69 i CD4070 i CQ407I , CD4072 I CD4073 I CD40':> I CD4076 ) CD4078 I CQ4081 I C04C62 f COH H6 I C04490 C04507 CO450B CD4S10 CD4511 I CD45I5 r CD45I6 ) CD45I9 I CD4520 ] CD4527 i CD4528 i £04553 ) CD4S6C ) CD45B3

74C10 74C14 74C20 74C30 74C48 74C74 74C76 74C90

74C221 74C90i ?;C<iC'i; 74C914 74C922 D 74C923 74C925 74C926 74C927

2 M 2114L JSOir 66 4116 200ns

.... 5 SO

- -J1I6 200ns 3500

MM5262 40

MM5280 3 00

MMS320 9 95

MM5330 5 94

PD4I1D3 4 00

PQ41ID 4 5 00

>3 key ASCII keyC-oa ! uliy «seniCled Enclosure Plashc

91L02A

2 SO

HD0165-5 6 95

MM57100 4 50

GIAY385O0I 9 95

MCM66751A 9 95

9366 3 50

4100 10 DC

416 16 QC

IC SOCKETS Solder Tin Lc* Profile PIN 1 OP PIN 1UP

WIRE WRAP LEVEL .1

14 95

2995

40

3 90

Z 10

MM5841

14 45

8 '5:

8 9S

MM 5 3 75 A A

3 30

mHS375aG

4 90

7 50

1=) iJj

4 95

QSCC26CN

3 75

3 7S

MM53104

2 50

MICROPROCESSOR

6502

SO 9i

(oOi

3 95

6522

9,95

6300

<; %

68-02

11 95

6820

68!.0

■

5 95

E0S5

12 95

■

^5 CO

780

■3 9;

2S0A

11 95

e;u

? 90

8 = l -i

3 95

e ;■ i f.

? rs

.

4 95

H25'

8253

15 DO

8255

5 75

:-.'-

10 95

B259

1495

ieo3CPpMs

13 95

1B020P pl«

l 7 95

1661P

9 50

CDP1B02CD

CDP1802O

3500

COP1B16P

7 95

UARI FIFO

HV5-I013

S5fl

7 5C

BS

3341

6 95

1 i",

J SO

PP.0M

W02A

4 95

h :..0 3 10

2708 271611

7 30

10 Mil]

18 MHz 20 MKi 32 MH: 32768m

1 84 32 MHl 3 5795MH?

2 OIO0 Mil;

2 097152 MHi

2 4576 MH;

3 2769 MHj 5 CG8S MH;

6 S53G MM) -1 50 14 31818 MH/ .| 25

IB 432 MHi 4 50

2? UB4 Mh.- 4 50

KErBOARDENCOOERS

AY5 2376 SI2 50

AV5 3600 17 95

AY5-9100 1050

AY5 9200 16 50

74C922 5 50

74C923 5 50

HD065 5 6 95

AY5 9460 10 50 D Cunneclail RS232

OB25P 3 E2

0B25S 520

Gr«, Orange Yellow JumDD 25

Ctiplile LED Maunllng Clips 5 Si 25 specify red. imtti gieen yeii<,n cicj'I

CONTINENTAL SPECIALTIES in slock CcmplelelineolbieadEioardlesleqiJip MAX.100 B digil Frcq Clr. 1149.95

OK WIRE WRAPTOOLSin ttack PorlaBle Mulllmeler Sifl 00

Cumplele liieol AP Protects in -A-.-.n

SPECIAL PRODUCTS

W7i 00

S229 CO

11? 5G 147 75

UEDmul89 95 2 6 95

IK 16K Eprom Kit

Hess cfiOMSI 589 CO Mclherboni) £3900

Clock Caleni 15 MH; Fre

3D Mil; F.tq

7KANSFORMEF1S

(j'.'j 0 ()■:,,•

12 Von 300 mi liar 12 6V CT E00 mi 12V 350 mi *itl rji 17V CI 250 ml *ll 24VC1 100 mi

DISPLAY LEOS

DL7D4 CC 300 1 75

DL707.OL70'R CA 300 I 00

OL727/728 CA.CC 500 1 90

DL747.750 CA.CC 600 1 95

3 20 8 2716 5 '

1 69 2732

2 75 275B 8197 169 874IA 8T98 1 69 8748

8748 8

87S5A

MDS/MEMORY R.1MN82S23

Jini.1 ■/ 85 NB75123

95 NB2S126

1 45 N82S179

165 NB2S131

4 95 NB2SI36

3 75 NB2S137 3 75 OM8577

BT25 BI26

8128

2102-1

2102AL4

21C2AN-2L

13 50

0IIB9 00

5500

19 SO 5500 5500

5500 55 CC

FNDB00.BO7 CC E

.

:i lype 012 :i type 6 75

14610 MAN4640 MAN47I0 MAN4740 MAh66'0 MAh671C MANC740

MAI002A. C. E MAI0I2A l02P3lrinslDrm>r MA10I2A TianjlDii

-P 3 95 8723

I 3 75

L300ns4 25

BSfl Controller S39.95

PROM Eraser

assembled. 25 PROM capacity S37.50 (with timer $69.50). 6 PROM capacity OSHA/ UL version $69.50 (with timer $94.50).

Z80 Microcomputer

16 bitl/O, 2 MHz clock. 2K RAM. ROM Breadboard space. Excellent lor control. Bare Board $26.50. Full Kit $99.00. Monitor $20.00. Power Supply Kit $35.00. Tiny Basic $30.00

S-100 Computer Boards

8K Static Godbout Econo HA Kit 149.00 16K Static Godbout Econo XIV Kit 269.00 24K Static Godbout Econo XX-24 Kit 414.00 32K Static Godbout Econo XX-32 Kit 537.00 16K Dynamic RAM Kit 289.00

32K Dynamic RAM Kit 328.00

64K Dynamic RAM Kit 399.00

Video Interface Kit $139.00

80 IC Update Master Manual $39.00

Comp. ICdata selector, 2700pg. master reference guide. Over 51,000 cross references. Free update service through 1980. Domestic postage $3.50.

Modem Kit $60.00

State of the art, orig., answer. No tuning necessary. 103 compatible 300 baud. Inexpensive acoustic coupler plans included. Bd. only $17.00 LRC 7000 + Printer $389.00 40/20 column dot matrix impact, std. paper. Interface all personal computers.

64/40/32/20 version $405.00. Optional cables available.

LRC 7000 printer interlace cable tar Super Elt with software $26.00

NiCad Battery Fixer/Charger Kit

Opens shorted cells that won't hold a charge and then charges them up, all in one kit w/full parts and instructions. $7.25

Rockwell AIM 65 Computer

6502 based single board with full ASCII keyboard and 20 column thermal printer. 20 char, alphanumeric display, ROM monitor, fully expandable. $375.00. 4K version $450.00. 4K Assembler $65.00, 8K Basic Interpreter $100.00.

Special small power supply for AIM65assem. in frame $54.00. Complete AIM65 in thin briefcase with power supply $499.00. Molded plastic enclosure to fit both AIM65 and power supply $47.50. Special Package Price: 4K AIM, 8K Basic. power supply, cabinet $599.00

AIM65/KIM/VIM/Super Elf 44 pin expansion board; 3 female and 1 male bus. Board plus 3 connectors $22.95.

60 Hz Crystal Time Base Kit $4.40

Converts digital clocks from AC line frequency to crystal time base. Outstanding accuracy.

Video Modulator Kit $9.95

Convert TV set into a high quality monitor w/o affecting usage. Comp. kit w/full instruc.

Multi-volt Computer Power Supply

8v 5 amp. ±18v .5 amp, 5v 1.5 amp. -5v .5 amp, 12v .5 amp, — 12v option. ±5v. ±12v are regulated. Basic Kit $29.95. Kit with chassis and all hardware $43.95. Add $4.00 shipping. Kit of hardware $14.00. Woodgrain case $10.00. $1.50 shipping.

RCA Cosmac 1802 Super Elf Computer $106.95

Compare features before you decide to buy any other computer. There is no other computer on the market today that has all the desirable benefits of the Super Ell for so little money. The Super Elf is a small single board computer that does many big things. It is an excellent computer for training and for learning programming with its machine language and yet it is easily expanded with additional memory, Full Basic, ASCII Keyboards, video character generation, etc. Before you buy another small computer, see if it includes the following features: ROM monitor; State and Mode displays: Single step; Optional address displays; Power Supply, Audio Amplifier and Speaker; Fully socketed for all IC's; Real cost of in warranty repairs; Full documentation. The Super Ell includes a ROM monitor for program loading, editing and execution with SINGLE STEP for program debugging which is not included in others at the same price. With SINGLE STEP you can seethe microprocessor chip operating with the unique Quest address and data bus displays before, during and alter executing instructions. Also. CPU mode and instruction cycle are decoded and displayed on 8 LED indicators. An RCA 1861 video graphics chip allows you to connect toyourown TV with an inexpensive video modulator to do graphics and games. There is a speaker system included for writing your own music or using many music programs already written. The speaker amplifier may also be used to drive relays for control purposes. A 24 key HEX keyboard includes 16 HEX keys

plus load, reset, run, wait, input, memory protect, monitor select and single step. Large, on board displays provide output and optional high and low address. There is a 44 pin standard connector slot for PC cards and a 50 pin connector slot for the Quest Super Expansion Board. Power supply and sockets for all IC's are included in the price plus a detailed 127 pg. instruction manual which now includesover40 pgs. of software info, including a series of lessons to help get you started and a music program and graphics target game. Many schools and universities are using the Super Elf as a course of study. OEM's use it for training and R&D. Remember, other computers only offer Super Elf features at additional cost or not at all. Compare before you buy. Super Elf Kit $106.95, High address option $8.95, Low address option $9.95. Custom Cabinet with drilled and labelled plexiglass front panel $24.95. All metal Expansion Cabinet, painted and silk screened, with room for 5 S-100 boards and power supply $57.00. NiCad Battery MemorySaverKit$6.95. All kits and options also completely assembled and tested.

Questdata, a software publication for 1802 computer users is available by subscription for $12.00 per 12 issues. Single issues $1.50. Issues 1-12 bound $16.50. Tiny Basic Cassette $10.00, on ROM $36.00, original Elf kit board $14.95. 1802 software; Moews Video Graphics $3.50. Games and Music $3.00, Chip 8 Interpreter $5.50.

Super Expansion Board with Cassette Interface $89.95

This is truly an astounding value! This board has been designed to allow you to decide how you want it optioned. The Super Expansion Board comes with 4K of low power RAM fully addressable anywhere in 64K with built-in memory protect and a cassette interface. Provisions have been made for all other options on the same board and it fits neatly into the hardwood cabinet alongside the Super Elf. The board includes slots for up to 6K of EPROM (2708. 2758, 2716 or Tl 2716) and is fully socketed. EPROM can be used forthemonitorandTinyBasicorotherpurposes. A IK Super ROM Monitor $19.95 is available as an on board option in 2708 EPROM which has been preprogrammed with a program loader/ editor and error checking multi file cassette read/write software, (relocatable cassette file) another exclusive from Quest. It includes register save and readout, block move capability and video graphics driver with blinking cursor. Break

Quest Super Basic V5.0

A new enhanced version of Super Basic now

available. Quest was the first company worldwide to ship a full size Basic for 1802 Systems. A complete function Super Basic by Ron Cenker including floating point capability with scientific notation (number range -.17EW). 32 bit integer -2 billion: multi dim arrays, string arrays; string manipulation; cassette I/O; save and load, basic, data and ma

points can be used with the register save feature to isolate program bugs quickly, then follow with single step. If you have the Super Expansion Board and Super Monitor the monitor is up and running at the push of a button. Other on board options include Parallel Input and Output Ports with full handshake. They allow easy connection of an ASCII keyboard to the input port. RS 232 and 20 ma Current Loop for teletype or other device are on board and if you need more memory there are two S-100 slots for static RAM or video boards Also a 1K Super Monitor version 2 with video driverfor full capability display with Tiny Basic and a video interface board. Parallel I/O Ports $9.85, RS 232 $4.50, TTY 20 ma l/F $1.95, S-100 $4.50. A 50 pin connector set with ribbon cable is available at $15.25 for easy connection between the Super Elf and the Super Expansion Board. Power Supply Kit for the complete system (see Multi-volt Power Supply).

chine language programs; and over 7 b statements, functions and operations. New improved faster version including renumber and essentially unlimited variables. Also, an exclusive user expandable command library.

Serial and Parallel I/O included. Super Basic on Cassette $55.00.

Gremlin Color Video Kit $69.95

32 x 16 alpha/numerics and graphics; up to 8 colors with 6847 chip, 1K RAM at E000. Plugs into Super Elf 44 pin bus. No high res. graphics. On board RF Modulator Kit $4.95

1602 16K Dynamic RAM Kit $149.00

Expandable to 32K. Hidden refresh w/clocks up to 4 MHz w/no wait states Addl 16K RAM $63.00 Super Elf 44 pin expansion board; 3 female and 1 male bus. Board plus 3 connectors $22.95 Tiny Basic Extended on Cassette $15.00

(added commands include Stringy, Array, Cassette I/O etc.)

S-100 4-Slot Expansion $ 9.95

Super Monitor VI.I Source Listing $15.00

Elf II Adapter Kit $24.95

Plugs into Elf II providing Super Elf 44 and 50 pin plus S-100 bus expansion. (With Super Expansion). High and low address displays, state and mode LED's optional $18.00.

Super Color S-100 Video Kit $129.95

Expandable to 256 x 192 high resolution color graphics. 6847 with all display modes computer controlled. Memory mapped. 1K RAM expandableto 6K. S-100 bus 1802,8080,8085,280 etc. Editor Assembler $25.00

(Requires minimum of 4K tor E/A plus user source)

1802 Tiny Basic Source listing $19.00

Super Monitor V2.0/2.1 Source Listing $20,00

TERMS: {5.00 mln. order U.S. Funds. Call) residents add 6% tax.

$10.00 mln. BankAmerlcard and Master Charge accepted. {1.00 Insurance optional. Postage: Add 5%. C.O.D. {10.00 mln. order.

FREE: Send tor your copy ol our NEW 1980

Circle 252 on inquiry card.

BYTE February 1981

347

Circle 253 on inquiry card.

WAMECO

THE COMPLETE PC BOARD HOUSE EVERYTHING FOR THE S-100 BUSS

MEM-3, 32K STATIC RAM BOARD

* 32K of 2114's

* Full 24 line address decoding. (Or bank select like the MEM-2)

* Expandable in 1K increments. (Board disabled for unloaded RAM)

* Bi-directional capability on data lines. (Board may be used as upper or lower 8 bits on a 16 bit bi-directional buss.)

* Addressable in 8K boundary within the 64K boundary selected.

* Kits less RAM $112.95.

With 2114L-4 $475.95.

With 2114L-2 $549.95.

Bare board $ 35.95.

Available mid January.

FUTURE PRODUCTS: 80 CHARACTER VIDEO BOARD. Z-80 CPU BOARD WITH ROM, 8 PARALLEL PORT I/O BOARD.

DEALER INQUIRIES INVITED, UNIVERSITY DISCOUNTS AVAILABLE

AT YOUR LOCAL DEALER

MOST PRODUCTS FOR IMMEDIATE SHIPMENT. NO 4-8 WEEK DELAYS REQUIRED FOR OTHERS.

W7J7C

inc.

WAMECO, INC., P.O. BOX 877 • 455 PLAZA ALHAMBRA • EL GRANADA, CA 94018 • (415) 726-6378

HOBBYWORLD's PRODUCT SPECIAL OF THE MONTH

D.C. HAYES Micromodem 100

A complete data communications system for S-100 microcomputers. It combines the capabilities of a serial interface card and an acoustic coupler. Also allows progammable auto dial, auto answer. Order by Catalog Number 2656

$339.95 («9. $379.95)

How to Order: Order by mail or phone (toll-free outside California). Pay by check, M.O., Visa

or Mastercard. Please include Card No., exp. date, and inter-bank no. on chargecard orders.

C.O.D.'s add $1.25 add'l. Add $2.00 shipping and handling for UPS Ground and $3.50 for UPS

Air. Mail orders: Include this ad. Phone orders: Specify Feb. Byte Special.

If the D.C. Hayes special price caught your eye, then order your FREE Hobbyworld Catalogue TODAY. It's filled with hundreds of quality products and special prices. Look thru the Hobbyworld Catalogue in the comfort of your home.

It's a great way to shop!

i FREE Hobbyworld Catalogue

~l

HOBBYWORLD

ELECTRONICS, INC.

B2

19511 Business Center Drive, Dept Northridge, California 91324

in U.S.A. (800) 423-5387 local and outside U.S.A. (213) 886-9200

348 BlfTE February 1981

I N

I I

ame

Company

I Address

I

City

State

_Zip_

Circle 254 on inquiry card.

THE STAR MODEM

From Livermore Data Systems

RS232 MODEM IEEE488 MODEM RS232 CCITT IEEE 488 CCITT

SALE $135

SALE $245

$170

$280

STAR Modem is the price performance leader with a full 2 YEAR FACTORY WARRANTY.

WE CARRY THE BLACK APPLE

_ Bell & Howell

MADl EXCLUSIVELY f OH RE LI >. HOWFl I BY

jcippkz computer inc.

EBS Business System (or PET/CBM $795

Extremely comprehensive package for small business. Fully integrated inventory and accounts receivable system including invoices, packing slips, mail labels, statements, bank deposit slips, and 17 reports. Allows any of -10 standard letters to be merged with customer record info on either a selective or complete file basis. Demo disk and system description available for $3.00.

0Z2 Data Base System lor C B M B03Z $335

Flexible file handling and report writing package for such applications as: Inventory Control; Management Information; Mailing List; Scheduling; Medical Record Keeping; Accounting.

KM MM Pascal lor PET $75

Subset of standard Pascal with true machine language translator for faster execution. 16K with tape or disk

EARL lor PET (disk file based) $65

Editor, Assembler, Relocater, Linker to generate relocatable object code.

(UIIF0RTH+ lor PET/CBM $65

A full-featured FORTH with extensions conforming to Forth Interest Groupstandards. Includesassembler.string processing capabilities, disk virtual memory multiple dimensioned arrays, floating point and integer processing.

Ml PLOT Intelligent Plotter by Watanabe Instruments (Digiplot)

SPECIAL $1145

• Incorporates all intelligent functions required for producing graphs and drawings including 8 vector and 4 character commands.

• Distance accuracy within 1%, repetition accuracy within .01 inches, programmable step size .004 inches, internal interpolation in .002 steps.

• Solid and broken line types can be specified.

• Character generator for letters, numerals and symbols. Characters can be enlarged and rotated in four orientations.

• Coordinate axes can be drawn by simply specifying the graduation inteival and number of repetitions.

• Self test mode automatically drawscompletetest pattern.

• Printer mode outputs character data in 16 sizes with 4 orientations.

• Connection to any microcomputer using parallel 7-bit ASCII code.

• Can use simple cable to parallel port, or special interface to IEEE or other.

• Modular control circuit and mechanical construction.

• Uses any hard fiber-tip pen.

• Uses 11x17 paper.

Includes power supply, I/O connector, 2 pens, 50 sheets of paper, and complete manual.

6502

7.45 10/6.95 50/6.55 100/6.15

6502A

8.40 10/7.95 50/7.35 100/6.90

6520 PIA

5.15 10/4.90 50/4.45 100/4.15

6522 VIA

6.45 10/6.10 50/5.75 100/5.45

6532

7.90 10/7.40 50/7.00 100/6.60

2114-L450

3.45 20/3.35 100/3.25

2114-L200

4.15 20/3.95 100/3.75

2716 EPROM (5 volt) 10.45 5/9.90 10/9.50

TMS 2532 EPROM 29.00

4116-200 pi RAM (NEC) 8 tar 35.00

S-100 Wire Wrap

2.65

commodore

CBM-PET SPECIALS

<<«, Up to $235 free

/^y merchandise with purchase of >i one of following CBM-PET items!

CASSETTES - AGFA PE-611 PREMIUM

High output, low noise, 5 screw housing, labels. C-10 10/5.65 50/25.0C 100/48.00

C-30 10/7.30 50/34.00 100/66.00

All other lengths available. Write for price list.

FREE

8032 32K - 80 Column CRT $1795 235

8016 16K - 80 Column CRT $1495 205

8050 Dual Disk Drive-1,020.000 Bytes $1795 235

A

ATARI 800 $777

All Atari Modules 20% OFF

SPECIAL-purchase ATARI 800, receive extra 8K memory FREE. EDUCATIONAL PLAN - buy 2 ATARI Computers, receive 1 ATARI 4O0 FREE!

DISKS

(write for quantity prices)

SCOTCH (3M) 5" 10/2.85 50/2.75 100/2.65

SCOTCH (3M) 8" 10/2.95 50/2.85 100/2.75

Maxell5" Double Dens. 10/4.25 50/4.10 100/3.95

Maxell8" Double Dens. 10/4.65 50/4.50 100/4.35

Verbatim 5" 10/2.45 50/2.40 100/2.35

(add .75 for 5" Verbatim plastic storage box)

Verbatim 8" Dbl. Dens. 10/3.35 50/3.25 100/3.15

BASF 5" soft 10/2.60 20/2.50 100/2.40

BASF 8" soft 10/2.40 20/2.35 100/2.30

Diskette Storage Pages 10 for 3.95

Disk Library Cases 8" - 2.85 5" - 2.15

CBM Modem - IEEE Interface CBM Voice Synthesizer 8N Full size graphics keyboard 16K Full Size Graphics or

Business Keyboard 32K Full Size Graphics or

Business Keyboard 2040 Dual Disk Drive - 343,000 bytes 2022 Tractor Feed Printer C2N External Cassette Deck Used PETs (8, 16, and 32K) WRITE FOR SYSTEM PRICES

"EDUCATIONAL DISCOUNTS**

Buy 2 PET Computers, get 1 FREE

CBM Full Size Graphics Keyboard $ 74

WordPro III - 32K CBM, disk, printer $170

WordPro IV - 8032, disk, printer $255

$395 50 $395 50 $795 100

$995 150

$1295 205

$1295 205

$795 100

$95 12

CALL

EPSON MX-80 Printer

$545

STARWRITER Daisy Wheel Printer

$1500

Centronics 737 Printer

$790

NEC Spinwriter- parallel

$2500

XYMEC Hl-Q 1000 Intelligent Daisy Wheel

$2150

Leedex Video 100 12" Monitor

$129

ZENITH DATA SYSTEMS

Zenith Z19 Terminal (factory asm.)

$735

Zenith Z89 with 48K

$2150

SYM-1

$209

SYM BAS-1 BASIC or RAE-1/2 Assembler

$ 85

KTM-2/80 Synertek Video Board

$349

KIM-1 (add $34 for power supply)

$159

Seawell Motherboard - 4K RAM

$195

Seawell 16K Static RAM - KIM, SYM, AIM

$320

VISICALC for PET, ATARI

BPI General Ledger, A/P, A/R for PET

Programmers Toolkit - PET ROM Utilities $34.90

PET Spacemaker Switch $24.90

Dust Cover for PET $6.90

IEEE-Parallel Printer Interface for PET $65.00

IEEE-RS232 Printer Interface for PET $149.00

115 E. Stump Road Montgomeryville, PA 18936

215-699-5826

A B Computers

KL-4M Four Voice Music Board and Visible Music Monitor (4 Voice) for PET $59.90

FLEXFILE Database-Report Writer by Michael Riley Flexible file handler for PET/CBM

MICRO-REVERSIfor PET by MFchaei'Riley" $9.95 Machine language version—you can't win at Level 5.

PAPER-MATE 60 Command PET Word Processor $29.95 Full-featured version by Michael Riley

A P Products 15% OFF APHobby-Blox 15% OFF

ALL BOOK and SOFTWARE PRICES DISCOUNTED

The 8086 Book (Osborne) $12.75

Z8000 Assembly Language Programming $10.60

PET Personal Computer Guide (Osborne) $12.75

PET and the IEEE-488 Bus (Osborne) $12.75

6502 Assembly Language (Osborne) $ 9.90

Programming the 6502 (Zaks) $10.45

6502 Applications Book (Zaks) $10.45

6502 Software Cookbook (Scelbi) $ 9.45

CP/M Handbook (w/ MP/M) Zaks $11.85

WRITE FOR CATALOG.

Add Si 25 per order tor shipping We pay balance ol UPS surface charges on all prepaid.orders Prices listed are on cash discount basis Regular prices slightly higher

$170 $270

Circle 255 on inquiry card.

BYTE February 1981 349

Circle 256 on inquiry card.

>!

CALIFORNIA COMPUTER SYSTEMS

32K RAM BOARD A&T.

450 NSEC $579.95, 200 NSEC $629.95

16K RAM A&T.

450 NSEC $255.95, 200 NSEC $285.95

64K DYNAMIC A&T.

200 NSEC $579.95

Z80 PROCESSOR A&T $259.00

DISC CONTROLLER $339.95

APPLE IEEE INSTRUMENTATION INTERFACE KIT 7490. Kil $275.00

ARITHMETIC PROCESSOR FOR APPLE 7811A. Kil $325.95

APPLE ASYNCHRONOUS SERIAL INTERFACE 7710A. Kil $89.95

APPLE SYNCHRONOUS SERIAL INTERFACE

7712A. Kil $89.95

ALL OTHER CCS PRODUCTS AVAILABLE

BStTl

PB-1 2708 & 2716 Programming Board with provisions for 4K or 8K EPROM. No external supplies required. Textool sockets. Kil $143 00

CB-1A 8080 Processor Board. 2K of PROM 256 BYTE RAM power on/rest Vector Jump Parallel port with status. Kil ..$146.00 PCBD $31.95

VB-3 80x24 VIDEO BOARD. Graphics included. 4MHZ $379.95

10-4 Two serial I/O ports with full handshaking 20/60 ma current loop: Two parallel I/O ports. Kit $168.00 PCBD $31.95

VB-IC 64 x 16 video board, upper lower case Greek composite and parallel video with software, S-100. Kit $143.00

CB-2 ZB0 CPU BOARD. Kit $199 95

AIO APPLE SERIAL/PARALLEL $144.95

ALL OTHER SSM PRODUCTS AVAILABLE

/inc. WAMECO INC.

MEM-3 32K STATIC RAM 2114 24 bit

addressing $32.95

FDC-1 FLOPPY CONTROLLER BOARD will drive shugart, pertek, remic 5" & 8" drives up to 8 drives, on board PROM with power boot up, will operate

with CPM'" (not included). PCBD $43.95

FPB-1 Front Panel. IMSAI size, hex displays. Byle,

or instruction single slep. PCBD $48 50

QM-12 MOTHER BOARD, 13 slot, terminated, S-100

board only $39.95

CPU-1 8080A Processor board S-100 with 8 level

vector interrupt. PCBD $28.95

RTC-1 Realtime clock board. Two independent interrupts. Software programmable. PCBD $25 95

EPM-2 2708/2716 16K/32K EPROM CARD.

PCBD $28.95

QM-9 MOTHER BOARD. Shorl Version of QM-12.

9 Slots. PCBD $33.95

MEM-2 16Kx8 Fully Buffered 2114 Board.

PCBD $28.95

PTB-1 POWER SUPPLY AND TERMINATOR BOARD,

PCBD $28.95

IOB-1 SERIAL AND PARALLEL INTERFACE. 2 parallel, one serial and cassette.

PCBD $28.95

2708 $7.50 2114L 450 NSEC $4.99

2716 $25.95 2114L 200 NSEC $5.99

WMB

(415) 726-9121 P.O. Box 955 • El Granada, CA 94018

Please send for IC, Xistor and Computer parts list

FEB. SPECIAL SALE ON PREPAID ORDERS

(Charge cards not included on tints offer)

WAMECO PCBD SALE.

MEM-2 EPM-2 $25.95

IOB-1, CPU-1 $24.95

PTB-1, RTC-1 $22.95

QMB-12 $32.95 QMB-9 $29.95

MIKOS PARTS ASSORTMENT WITH WAMECO AND CYBERCOM PCBDS MEM-2 with MIKOS =7 16K ram

with L2114 450 NSEC $229.95

MEM-2 with MIKOS "13 16K ram

with L2114 200 NSEC $249.95

CPU-1 with MIKOS *2 8080A CPU $99.95

OM-12 with MIKOS CA 13 slot mother

board $11 0.95

RTC-1 with MIKOS "5 real time clock $65.95

EMP-1 with MIKOS "10 4K 1702 less

EPROMS $ 49.95

EPM-2 with MIKOS "11 16-32K EPROMS

less EPROMS $65.95

QM-9 with MIKOS "12 9 slot mother

board $99.95

FPB-1 with MIKOS *14 all parts

for front panel $144.95

MIKOS PARTS ASSORTMENTS ARE ALL FACTORY MARKED PARTS. KITS INCLUDE ALL PARTS LISTED AS REQUIRED FOR THE COMPLETE KIT LESS PARTS LISTED. ALL SOCKETS INCLUDEO

LARGE SELECTION OF LS TTL AVAILABLE PURCHASE S50 00 WORTH OF LS TTL AND GET 10°oCREDITTOWARD ADDITIONAL PURCHASES. PREPAID ORDERS ONLY.

number, interbank num.

VISA or MASTERCHARGE. Send account ber, expiration date and sign your order. Appro* postage wil be added. Check or money order will be sent post paid in U.S. It you are not a regular customer, please use charge, cashier's check or postal money order. Otherwise there will be a twoweek delay for checks to clear. Calif, residents add 6% tax. Money back 30-day guarantee, we cannot accept returned IC's that have been soldered to. Prices subject to change without notice. $10 minimum order. $1.50 service charge on orders less than $10.00.

BECKIAN E

ALL PRIME QUALITY - NEW PARTS ONLY

SATISFACTION GUARANTEED.

EDGE CARD CONNECTORS:

GOLD PLATED:

Abbreviations: S/E Solder Eye

. S/T Sold Tail:

W/W Wire Wrap.

PART # DESCRIPTION. Row Sp.

1 9pc.

1 0-24pcs

25pcs. Up.

.156" CONTACT CENTER CONNECTORS.

D' TYPE SUBMINIATURE CUNNECTURS.

BRAND:

TEXAS INST.

PART * DESCRIPTION.

Row Sp.

1 9pc.

10-24pcs. 25pcs. Up.

QUANTITY

4070

13.9588,

•3.55ee.

(3.15.8.

15105

6112 SIE PET/NSC

.140

• 1.86

• 1.65 »1.45

4090

501100 ImsaiWIW .250

4.3088.

3.65bb.

3.4588.

15110

6112 SIT PETINSC

.140

1.65

1.65 1.50

PART NUMBER DESCRIPTION. 19pcs. 10 24pcs.

2599pcs.

BRANO:

SULLINS: u.l Rag.

15137

6112 SIT PETINSC

.200

1.80

1.54 1.45

DF

9P Mele •1.66ee. 11.4000.

•1.30ae.

12986S

501100 Soldar Eye .140

6.808a.

6.10BB.

5.4588.

15175

61 SIE Sgle Row

1.70

1.50 1.30

DF

129670

50/100 SIT Imiai .250

4.50ee.

4.1 Oaa.

3.70

15270

16120 SIE

.146

2.15

1.95 1.70

DF

1109631 2 pc. Grey Hood. 1.50ea. 1.35ee.

12987S

501100 WIW Imiai .250

5.25

4.75

4.20

15275

10126 SIT

.140

2 00

1.85 1.60

129BB5

50I1DOSIT Altair .140

4.95

4.45

3.95

15435

12124 SIE PET

.140

2.66

2.35 2.10

DA

15P Male 2.35ee. 2.15ee.

2.0088.

129990

501100 SIT Cromnrn. .250

4.75

4.25

3.60

15440

12124 SIT PET

.140

2.65

2.40 2.15

DA

15S Female 3.25B0. 3.1088.

2.9088.

15445

12124 SfT PET

.200

2.75

2.50 2.20

DA

512111 1. pc. Grey Head 1.40ee. 1.20ss.

1.15oa.

OTHER .

125" CONTACT CTR CONNECTORS

15505

15136 SIE GRI Key

.146

2.50

2.25 2.00

OA

51226 1 2 pc. Block Hood 2.50ee. 2.25ee.

2.0088.

12305

22144 SIE No Eari .140

4.15

3.75

3.35

15510

15130 SIT GRI Key

.140

2.40

2.15 2.95

OA

1109632 2 pc. Grey Hood t.60aa. 1.35ee.

1.30oe.

12759

36172 SIT .140

6.40

4.85

4.35

15515

15130 WIW GRI Key .200

2.60

2.35 2.10

DB DB

25P Mele 2.60ee. 2.B0ee. 25S Female 3.60ee. 3.40ea.

2.4088. 3.2088.

12790

40160 WIW .250

8.30

6.65

5.00

15600 15616

16136 SIE 16136 SIT

.140 .140

3.35

3.00

3.05 2.70 2.70 2.46

.100" CONTACT CTR CONNECTORS:

15815

18136 WIW

.200

360

3.20 2.90

UB

512121 1 pc. Grey Hood 1.50ee. 1.30ee.

l.lOaa.

10046

13126 SIE No Eari .146

346

3.05

2.15

15700

22144 SIE KIMIVEC

.140

2.96

2.90 2.75

DB

512261 2 pc. Block Hood 1.96ee. 1.65ea.

1.4588.

10260

25150 SIE TRS 66 .146

4.56

4.05

360

15705

22144 SIT KIMIVEC .140

3.96

3.30 3.06

10175

26146 SIE TRS 80 .146

5.85

5.35

4.75

15716

22144 WIW KIMIVEC .200

3.49

3.20 2.65

Dr.

37P Mele 4.20ee. 4.00ea.

3.70oa.

10190

26146 WIW TRS B6 .200

3.30

3.00

2.15

15875

25150 SIE

.140

4.65

4.20 3.75

DC

5.5088.

10190

26140 SIT TRS 66 .146

3.20

2.90

2.55

15B66

25150 SIT

.140

4.55

4.10 3.65

no

1.75D0.

10405

36172 SIE Vactar .140

5.50

4.90

4.40

15665

25150WIW

.200

4.85

4.35 3.96

10490

36172 WIE Vector .200

5.80

6.25

4.65

16115

36172 SIE

.140

6.50

5.05 5.20

uu

50P Mele 5.50ee. 5.108a.

4.7588.

10500

36172 SIT Vector .146

5.70

4.20

4.66

16120

36172 srr

.140

6.55

5.90 5.25

DU

50S Female 9.4DOB. 8.60BB.

B.OOeo.

10535

40160 SIE PET .140

6.86

5.35

4.75

16125

36172 WIW

.200

6.75

6.16 5.46

UU

512161 1 pc. Cray Hood 2.40ee. 2.20ee.

2. 0088

10540

40166 WIW PET .200

6.00

5.40

4.86

16145

36172 srr

.200

6.50

5.65 5.26

UU

1109635 2 pc. Grey Hood 2.60a8, 2.40aa.

2.1088

10550 10565

40160 srr pet .140

43166 SIE C0SIELF .146

5.80 6.95

5.25 6.25

4.65 5.55

16235 16246

43166 SIT Mat 6666 .146 43166 WIW Mot 6660 .200

6.60 7.60

5.95 5.30 7.65 6.25

D

20418-2 Hardware Set .90ee. .OOea. 11 Hood Sell

.7088.

10605

43166 SIT C0SIELF .146

6.60

6.95

5.30

16260

43166 SIT Mat 6666 .200

6.50

5.65 5.20

10595

43I66WIWC0SIELF .200

6.90

6.20

5.95

16725

43186 SIE Mot 6600 .146

7.20

6.50 5.75

10615

43I66SITC0SIELF .200

6.80

8.10

5.40

K1

PalKeys

.15

.12 .10

IC. SOCKETS GOLD.

COOLING

FANS.

TERMS: MINIMUM ORDER: S 15.00 ADD S1

.35 For

WIWRAP 3 TURN

Extra Ouiet.

Handling & Shipping. Orders over S 30.00 in th

! U.S.A.

14 pio

•0.46 ee

14 pin

• 0.15 ee.

1 to 4

• 18.00 oa.

We Pay the Shipping. CALIF. RESIDENTS: Please Add

16 pin

0.54 ee

16 pin

0.17 ee.

5 to 9

17.00 oe.

6% Sales Tax.

NOTE: NO COD. OH CREDIT CARD ORDERS ACCEPTED.

WILL BE

.6060A PRIME

•5.00 ee.

CONNECTORS F

)R CENTRONICS 706 SERIES. hnnol 57 30366

PHONE: 213-988-6196

BECKIAN ENTERPRISES

EIA 8 CONDUCTOR CABLES Bft. Una.

CLASS #1 Type

Cobles.

1

MAIL ORDERS TO:

P.O. BOX #3089

1. to 4 pes. 5 to 9 pes.

•22.00 19.00

6

to 9 pes.

6.00 ■«■

SIMI VALLEY, CA 93063

350 BYTE February 1981

Circle 257 on inquiry card.

DIGITAL RESEARCH COMPUTERS

(214)271-3538

32K S-100 EPROM CARD NEW!

USES 2716's Blank PC Board - $34

ASSEMBLED & TESTED ADD $30

SPECIAL: 2716 EPROM's (450 NS) Are $11.95 EA. With Above Kit.

KIT FEATURES:

1 Uses +5V only 2716 (2Kx8) EPROM's.

2 Allows up to 32K of software on line1

3. IEEE S-100 Compatible.

4. Addressable as two independent 16K blocks.

5. Cromemco extended or Northstarbank select.

7. Any or all EPROM locations can be

disabled. S. Double sided PC board, solder-masked,

silk-screened. 9. Gold plated contact fingers

10. Unselected EPROM's automatically powered down for low power.

11. Fully buffered and bypassed.

6. On board wait state circuitry if needed. 12. Easy and quick to assemble.

32K SS-50 RAM

$37900 k,t

For2MHZ Add $10

Blank PC Board

$50

For SWTPC 6800 - 6809 Buss

Support IC's

and Caps

$19.95

Complete Socket Set

$21.00

Fully Assembled,

Tested, Burned In

Add $30

At Last! An affordable 32K Static RAM with full 6809 Capability.

FEATURES:

f. Uses proven low power 2114 Static RAMS.

2. Supports SS5DC - EXTENDED ADDRESSING.

3. All parts and sockets included.

4. Dip Switch address select as a 32K block.

5. Extended addressing can be disabled.

6. Works with all existing 6800 SS50 systems.

7. Fully bypassed. PC Board is double sided, plated thru, with silk screen.

16K STATIC RAM KIT-S 100 BUSS

.'HTiTiTiTTTmTW'TlfmTnmi

1. Addressable as four separate 4K Blocks.

2 ON BOARD BANK SELECT circuitry (Cromemco Standard1). Allows up to 512K on line1

3 Uses 2114 (450IMS) 4K Static Rams

4 ON BOARD SELECTABLE WAIT STATES.

5. Double sided PC Board, witnsolder mask and silk screened layout. Gold plated contact fingers

6. All address and data lines fully buffered. ASSEMBLED & TESTED-ADD $35

7 Kit includes ALL parts and sockets

8 PHANTOM is jumpered to PIN 67 9. LOW POWER: under 1 5 amps TYPICAL from the »8 Volt Buss

10 Blank PC Board can be populated as any multiple of 4K.

BLANK PC BOARD W/DATA-$33

LOW PROFILE SOCKET SET-$12

SUPPORT IC'S & CAPS-$19.95

OUR #1 SELLING RAM BOARD!

*&* STEREO! Afe*.

S-100 SOUND COMPUTER BOARD

COMPLETE KIT! $8495

(WITH DATA MANUAL)

At last, an S-100 Board that unleashes the full power of two unbelievable General Instruments AY 3-8910 NMOS computer sound IC's. Allows you under total computer control to generate an infinite number of special sound effects for games or any other program. Sounds can be called in BASIC. ASSEMBLY LANGUAGE, etc. KIT FEATURES: » TWO Gl SOUND COMPUTER IC'S.

* FOUR PARALLEL I/O PORTS ON BOARD

* USES ON BOARD AUDIO AMPS OR YOUR STEREO. » ON BOARD PROTOTYPING AREA.

* ALL SOCKETS PARTS AND HARDWARE ARE INCLUDED

* PC BOARD IS SOLDERMASKED. SILK SCREENED. WITH GOLD CONTACTS » EASY, QUICK. AND FUN TO BUILD WITH FULI INSTRUCTIONS

* USES PROGRAMMED I/O FOR MAXIMUM SYSTEM FLEXIBILITY Both Basic and Assembly Language Programming examples are included

SOFTWARE: SCL'"is now avail able! Our Sound Command Language makes writing Sound Effects programs aSN AP1SCL'" also includes routines for Register-Examine-Modify, Memory-Examine-Modify, and Play-Memory. SCL" is available on CP/M' compatible diskette or 2708 or 2716. Diskette $24.95 2708 - 519.95 2716 - S29.95. Diskette includes the source EPROM'S are ORG at E000H

16K STATIC RAM SS-50 BUSS

PRICE CUT!

11 Illl;l'l:iftl;|'|;t-I:i I

$195

KIT

FULLY STATIC!

FOR 2MHZ ADD $10

iiiiiiiiiiiiiiii

FOR SWTPC 6800 BUSS!

ASSEMBLED AND TESTED - $35

KIT FEATURES

1 Addressable on 16K Boundaries

2 Uses 2114 Static Ram

3 Fully Bypassed

4 Double sided PC Board Solder mask and silk screened layout

5 /*'! Parts and Sockets included

6 Low Powei Under 1 5 Amps Typical

BLANK PC BOARD—$35 COMPLETE SOCKET SET—$12

SUPPORT IC'S AND CAPS—$19.95

BLANK PC

BOARD W/DATA

$31

4K DYNAMIC RAM BLOWOUT!

SAME AS INTEL 2107B!

4K RAMS AT AN UNBELIEVABLE 50C EACH!!!

Prime, new, National Semi., 1979 date coded, lull spec, parts. N.S. #MM5280-5N. Same as INTEL 2107B-4, T I. TMS4060, NEC UPD411, etc. We bought a HUGE QTY. from a West Coast Distributor at truly DISTRESS PRICES! One ol the most popular and reliable RAM's ever made. These parts have been used by almost all Major Computer Main Frame Mfg. the world overi Arranged as 4K x 1, 270 NS Access Time, 22 Pin Dip. These units DO NOT use multiplexed addressing, thus making REFRESH and other timing very simple. See INTEL MEMORY DESIGN HANDBOOK for full application notes. The NAT. SEMI. MEMORY DATA BOOK is available at most Radio Shack Stores. Prime units in original factory tubes!

.^ #5280-5N 4096 BITS x 1 270 NS ACCESS

^%»^ 8 FOR $4.95 32 FOR $16

FACTORY CASE (450 PCS) — $180 Sockets Special: 22 Pin Low Profile (With Purchase ot 5280s) 8 FOR S1.

COMPUTER PARTS SPECIALS

74LS175 - .99 8035 Intel Single Chip CPU 6.95

74LS240 - 1.19 Signetics 2901 4 Bit Slice - 6.95

74LS241 - 1.19 AMD 2903 4 Bit Super Slice - 12.50

74LS244 - 1.19 AMD 29705 Dual Port RAM - 8.95

74LS373 - 1.29 Intel 2716-1 (350 NS) - 12.95

NEW! G.I. COMPUTER SOUND CHIP

AY3-8910. As featured in July. 1979 BYTE1 A fantastically powerful Sound & Music Generator Perfect for use with any 8 Bit Microprocessor Contains 3 Tone Channels. Noise Generator. 3 Channels of Amplitude Control 16 hit Envelope Period Control. 2-6 Bit Parallel I/O. 3 D to A Converters, pins much more1 All in one JO Pin DIP. Super easy interface to the S-100 or other busses $11.95 PRICE CUT!

SPECIAL OFFER: 514.95 each Add $3 for 60 page Data Manual

Digital Research Computers

** (OF TEXAS) '

P.O. BOX 401565 • GARLAND, TEXAS 75040 • (214) 271-3538

TERMS: Add $1 50 postage. We pay balance. Orders under $15 add 75<t handling No COD. We accept Visa and MasterCharge. Tex. Res. add 5% Tax. Foreign orders (except Canada) add 20% P & H. Orders over $50, add 85$ for insurance.

'TRADEMARK OF DIGITAL RESEARCH.

Circle 258 on inquiry card.

WE ARE MOT ASSOCIATED WITH DIGITAL RESEARCH OF CALIFORNIA. THE SUPPLIERS OF CPM SOFTWARE.

BYTE February 1981 351

64K BYTE EXPANDABLE RAM

DYNAMIC RAM WITH ON BOARDTRANSPARENT REFRESH GUARANTEED TO OPERATE IN NORTHSTAR. CROMEMCO, VECTOR GRAPHICS, SOL. AND OTHER 8080 OR Z-80 BASED S100 SYSTEMS «4MHZ Z-80 WITH NO WAIT STATES. . SELECTABLE AND DESELECTABLE IN 4K INCREMENTS ON 4K ADDRESS BOUNDARIES. . LOW POWER-8WATTS MAXIMUM. . 200NSEC 4116 RAMS . FULL DOCUMENTATION. . ASSEMBLED AND TESTED BOARDS ARE GUARANTEED FOR ONE YEAR AND PURCHASE PRICE IS FULLY REFUNDABLE IF BOARD IS RETURNED UNDAMAGED WITHIN 14 DAYS.

ASSEMBLED/ TESTED

64KRAM $595.00

48KRAM S5Z9.00

32KRAM $459.00

16KRAM $389.00

SI00 MAINFRAME AND CARD CAGE

* W/ SOLID FRONT PANEL . . S239.00

* W/ CUTOUTS FOR 2 MINI-FLOPPIES . . . S239.00

* 30 AMP POWER SUPPLY S119.00

* 8 SLOT MOTHERBOARD S149.00

19 SLOT MOTHERBOARD $199.00

1EK MEMORY EXPANSION KIT ONLY S58 FOR APPLE, TRS-80 KEYBOARD, EXIDY, AND ALL OTHER 16K DYNAMIC SYSTEMS USING MK4116-3 OR EQUIVALENT DEVICES.

* 200 NSEC ACCESS, 375 NSEC CYCLE

* BURNED IN AND FULLY TESTED

• 1 YR. PARTS REPLACEMENT GUARANTEE

• QTY. DISCOUNTS AVAILABLE

VISTA V-200 MINIFLOPPY SYSTEM

• S100 DOUBLE DENSITY CONTROLLER

• 204 KBYTE CAPACITY FLOPPY DISK DRIVE WITH CASE & POWER SUPPLY

• MODIFIED CPM OPERATING SYSTEM WITH EXTENDED BASIC

$695.00

COmPUTER DEVICES

1230 W.COUinS AVE.

ORflflGe, Cfl 92668

(714)633-7280

32K BYTE MEMORY

RELIABLE/COST EFFECTIVE EXPANDABLE BAM FOR

650Z AND 6BO0 SYSTEM-AIM 65-'KIM'SYM-PET-S44-BUS

. PLUG COMPATIBLE WITH THE AIM-65/SYM EXPANSION CONNECTOR BY USING A RIGHT ANGLE CONNECTOR (SUPPLIED) MOUNTED ON THE BACK OF THE MEMORY BOARD.

. MEMORY BOARD EDGE CONNECTOR PLUGS INTO THE 6800 S 44 BUS.

• CONNECTS TO PET OR KIM USING AN ADAPTOR CABLE.

• RELIABLE-DYNAMIC RAM WITH ON BOARD INVISIBLE REFRESH-LOOKS LIKE STATIC MEMORY BUT AT LOWER COST AND A FRACTION OF THE POWER REQUIRED FOR STATIC BOARDS.

• USES +5V ONLY. SUPPLIED FROM HOST COMPUTER.

. FULL DOCUMENTATION. ASSEMBLED AND TESTED BOARDS ARE GUARANTEED FOR ONE YEAR AND PURCHASE PRICE IS FULLY REFUNDABLE IF BOARD IS RETURNED UNDAMAGED WITHIN 14 DAYS.

ASSEMBLED WITH 32K RAM $395.00

S WITH 16K RAM S339.00

TESTED WITHOUT RAM CHIPS $279.00

HARD TO GET PARTS (NO RAM CHIPS)

WITH BOARD AND MANUAL $109.00

BARE BOARD S MANUAL $49.00

ififcMiftmw

PET INTERFACE KIT-CONNECTS THE 32K RAM BOARD TO A 4K OR 8K PET. CONTAINS: INTERFACE CABLE, BOARD STANDOFFS, POWER SUPPLY MODIFICATION KIT AND COMPLETE INSTRUCTIONS S49.00

U.S. PRICES ONLY

Add-On

Disk Drive

Subsystems

FOr Apple, TRS-80, S-100 Based Computers

Expansion and enhanced capabilities are key words in achieving full utilization of your computer system. Our complete line of LOBO disk drive subsystems are the ideal, cost-effective way to provide the expansion capabilities you need to meet your system growth requirements. All of our subsystems are complete, thoroughly-tested, 100% burned-in, and feature a 1 year 100% parts/labor warranty.

APPLE

3101 Minifloppy, 31011 Minifloppy w/interlace card

6101CA One SA800 in cabinet w/power, DDC* Controller, cable and manual 8202CA Two SA800 in cabinet w/power, DDC" Controller, cable and manual 5101CA One SA850 in cabinet w/power, DDC* Controller, cable and manual 5202CA Two SA850 in cabinet w/power, DDC* Controller, cable and manual "Double Density Controller

S-100 BASED COMPUTERS

MODEL NO DESCRIPTION

41 01C SA4DO in cabinet w/power

8212C Two SA801 in cabinet w/power

521 2C Two SA851 in cabinet w/power

GENERAL

MODEL NO DESCRIPTION

8212 Two SA801 in cabinet

8212C Two SA801 in cabinet w/power

5212 5212C

Two SA851 in cabinet

Two SA851 in cabinet w/power

TRS80

MODEL NO DESCRIPTION

4101C SA400 in cabinet w/power

8101C II One SA800 in cabinet w/power lor Mod.

8202C II Two SA800 in cabinet w/power lor Mod.

C802 Cable lor Mod. II

C805 Cable lor TRS80 Minifloppy

MODEL NO.

DESCRIPTION

C808

Cable lor TRS80 Eight inch Floppy

LX80

Double density expansion interface

RS232

Dual Serial Port Option

16K

16K Byte RAM for LX80 (32KB max.)

VTOS

4.0 Disk Operating System

CO.,

P.O. Box 185, Santa Yhez,Ca., 93460 (805) 688-8781

352 BYTE February 1981

Circle 259 on inquiry card.

1858 Evergreen Street, Duarte, California 91010

Phone 213-357-5005

page

DIGITAL ELECTRONICS II

PRB1 LOGIC PROBE PLS1 LOGIC PULSER

PRB1 LOGIC PROBE

$36.95

» Compatible with all logic families

• Visual indication of low, high and bad logic levels

• Pulse stretching to 50 Msec

* PLS1 LOGIC PULSER

INSERTION/EXTRACTION TOOLS

WW1 WIRE WRAPPING KIT

ORDERING INFORMATION:

• Orders under $25 include $2 handling

• All prepaid orders shipped UPS Ppd.

■ Visa, MC & COD's charged shipping.

• All prices good through cover date.

■ Most orders shipped same day.

• Byte must be mentioned to get sale price.

$48.95

• Superimposes 20pps pulse train onto circuit

• No need to cut circuit trace

• Automatic pulse polarity

WK7 INSERTION/EXTRACTION KIT $29.95

• MOS safe

• Includes EX1 & EX2 Extraction tools

• MOS 1416, MOS 2428, MOS 40 Extraction tools

• MDD1 1 channel dispenser $ 21.85

• MDD5 5 channel dispenser 83.43

• MDD10 10 channel dispenser 160.45

• Dispenses 8-42 pin IC's

8 Compatible with all IC carrying tubes

• Use with WK7 for MOS-safe IC insertion

WW1 WIRE WRAPPING KIT

• BW2630 Power wrapping tool $19.85

• BT30 #30 Bit 3.95

• BC1 Batteries and charger 14.95

• KIT#3 Precut wire kit 32.95

• 10 ea. 14 pin, 16 pin gold wrap sockets 11.00

• EZO7302 4.25" x 8.5" Glass epoxy board 3.95

• 14ID,16ID20ICwrapindentifiers 3.96

TOTAL $90.01 SALE PRICE $69.95

Write or call for 1980 catalog

• IC Sockets

» Vector Board & Pins

• Bishop Drafting Aids « OK Tools

• RN IDC Crimp Connectors

Circle 260 on inquiry card.

TOLL FREE ORDERING NUMBER 1-(800)-423-7144

S-100 VOICE

The ARTICULATOR board allows you to record, store, and playback any vocabulary on your S-100 computer. Input speech is digitized by the ARTICULATOR and sent to the computer via an on-board port for storage at 1K to 2K bytes/sec. This data is then sent back from the computer to the ARTICULATOR for very high quality playback. On-board VOX switching minimizes memory storage requirements.

PRICE — $319 A&T AVAILABLE NOW

Quintrex, Inc., 9185 Bond Shawnee Mission, Ks. 66215 (913) 888-3353

for TRS-80 '

CUSTOM SOUND

";'™"',°r," u.rt.d™!.b™M°S.*Uw»rt

The device is cupnblo of producing three

simu 1 t.-incoiis tone music of any note structure (ii

just ocUvcs) ;is well sis complex sound effects

[sirens, etc), All this :n :i frriction 01" the c

St

nf corn,).,r..l>]c units, with the doulilc cable, t>

units can be "Rrmjieil" togctlitr in produce sis

SOUND GENERATOR KIT: [needs only

cablu,5VSC 5 speaker)

- S49

two fur

$80

CABLE: ribLon cable with PC edge connectors,

or EX/lltT.

y/u

double connector

S25

SVDC REGULATlili POKEK SUI'i'LV:

fully nssnbLcd, 1.2 nop, ovr.

• S23

kit cones complete wit!, s,P|,lu software S

COMING SOON.' SPEECH SYNTHESISER

IXQUIHES WELCOMU

'ustom ••""•" * Jeripherals f*.*tS?

Don 8759 Warwick, llhodr Mand 028S8

SUBMINI DPDT DIP RELAY

AROMAT KHB2-DCBV

SI SO each 10lorSl350

40 PIN RT ANGLE P.C.B.

mm HEADER

^ RIGHT ANGLE

$1 .50 EACH MOUNT

40 PIN RIBBON CABLE SOCKET CONNECTOR fr=--£55A 3M"34I7

few*- s. c0 f-ACH

22/44 EDGE CONNECTOR

TIN SOLDERTAIL ,156"x .200"

vssssssss&t

LARGE QUANTITIES AVAILABLE 11.35 each 10 lor $12.50

7-17wdc S.S. BUZZER

Si 25 each

FLAT LEVER HANDLE 'MINI TOGGLE

S PDT RATED

6 AMPS (63 125 V 14 - 40 BUSHING

$1.00 each

10 lorsa 50

Litronix FRL-4403

FLASHER LED

dilluseuiedled

buill in flashing ui

ALL 6L6CTRO0ICS CORP.

905 S. Vermont Ave. terms

Los Angeles, Calif. 90006 (213)380-8000 Mon. - Fri. Saturday 9 AM-5 PM 10 AM-3 PM

SEND FOR

Quantities Limited Min. Order SI 0,00 Add 12.00 Shipping USA Calil.Res Add6% Prompt Shipping

FREE CATALOG

Circle 261 on inquiry card.

Circle 262 on inquiry card.

Circle 263 on inquiry card.

NEW!

interface Converts

Your Typewriter

into printer

- Finest print quality • Low cost

■ Easy Installation ■ Quick delivery

• Fits IBM SELECTR ic8 typewriter with no modification.

• For trs-808, Apple®, or any parallel or RS232 port.

• write or phone for more information, today!

■ U.S. and worldwide sales—

INTERNATIONAL INC.

16140 valerio St.

van Nuys.CA 91406 USA

TEL: 213/781-0020 TLX/TWX: 910-495-1767

iPEX

WANTED:

APPLE, PET, TRS-80, CP/M

SOFTWARE

Westico is a publisher and distributor of professional software for microcomputers. If you have a new program ready for distribution or want yourexisting programs to reach a larger market, contact:

Phillip Woellhof. V.P. Mktg.

Westico. Inc.

25 Van Zant Street

Norwalk. CT 06855

(203) 853-6880 To increase your profits, take advantage of Westico's worldwide promotion and distribution

WESTICO

The Software Express Service

B Dysan

^CORPORATION

Solve your disc problems, buy 100% surface tested Dysan M*\*anm All orders shipped from stock, within 24 hours. Call toll FREE (BOO) 2354137 for prices and information. Visa and Master Card accepted All orders sent postage paid.

PACIFIC EXCHANGES

100 Foothill Blvd. San Luis Obispo. CA 93401. (In Catcall (805) 543-1037.)

Circle 264 on inquiry card.

Circle 265 on inquiry card.

COMPUTER

SORPLUS

**************

POWER SUPPLIES: 110(g>220 vac. mulli

volt and multi amp ($20-$45).

VIDEO TERMINALS with KEYBOARDS

($50-$150).

MUFFIN FANS $5.

FILTER CAPACITORS (large canistors)

$1 ea.

ALSO LARGE COMPUTER CABINETS

$30-$100.

40 wire ribbon cable 50c per foot

20 wire ribbon cable 25c per foot

RELAYS, CONNECTORS, FUSE HOLDERS, BREAKERS, HEAT SINKS, SWITCHES,..etc. also for sale.

CALL K1RT WYCKOFF at (216) 473-0866

DATA HARDWARE

701 #4 BETA DR. CLEVELAND OHIO 44143

DEALERS WELCOME

!! REAL TIME

! !

The TIME MACHINE from ALPHA OMEGA COMPUTER SYSTEMS isn't just another digilal clock chip surrounded by interface circuitry. It's an intelligent microcompuler

The TIME MACHINE communk itM with your computer 300 and 2400 baud. RS-232, RS-422, or current loop

Battery protection against power loss is included. The TIME MACHINE automatically computes day ol the week and leap year. Buttered output pulses at one second, one

; are 2.5 <l.?5> 7.5 i

Price is only $450 single lot and quantity discounts a available. Dealer inquiries invited. Oil the shell deli

ALPHA

OMCCACOMPUTCR SUSTCMS, INC.

<ox

Save up to 50%

using our buying power. We buy over three million dollars of computer equipment wholesale per year for clients who range in size from the largest manufacturers to the home hobbyist. Our fee is one fourth of what we save you off the manufacturer's suggested list price, so it is to our advantage to save you money.

THE PURCHASING AGENT 163S School Street, Suite 101 Moragn, CA 94556 (415) 376^)020

Circle 266 on inquiry card.

Circle 267 on inquiry card.

Circle 268 on inquiry card.

WE WILL NOT BE UNDERSOLD

DISK DRIVES

$314

40 track, 102K Bytes. Includes power supply and TRS-80* compatible silver enclosure. Ready to plug-in and run the moment you receive it. Can be intermixed with each other and Radio Shack drive on same cable. 90 day warranty. One year on power supply. Available for 220 Vac (50 Hz) operation. External card edge included.

FOR TRS-80*

CCI-100

CCI-280

For Zenith Z89

CCI-189

Z-87

DISKETTES — Box of 10 with plastic library case 51/<" Scotch $35 Maxell $40

8" Scotch $50 Maxell $55

CLEAR PLASTIC CASE-Holds 50 diskettes

|gl4V«[i!iIrf*ItM:l»k

MAINFRAME, Z-80 CPU, CONTROLLER, RAM, and 2P + 2S CARDS

8" SHUGART SA801R DISK DRIVES DISK OPERATING SYSTEMS

51/4",40Track(102K Bytes) for Model I $314

51/«", 80 Track (204K Bytes) for Model I $429

5 Va ", 40 Track (102K Bytes) add-on drive $394

Dual 5Vt "add-on drive system $995

BASF/Verbatim $24

BASF/Verbatim $36

$19

$CALL

$425

PATCHPAK#4byPercom Data

$ 8.95

CP/M® for Model I, Zenith $145 •

for Model II, Altos

$169.00

NEWDOSPIus

40track

$ 79.00

NEWDOS 80

$135.00

COMPLETE SYSTEMS

ALTOS ACS8000 Computers

$ CALL

APPLE 16K

$939

APPLE III 96K

$2999

TRS-80* Model II-64K

$3499

TRS-80* Model III-16K

$899

TRS-80* Expansion interface

$249

ZENITH Z89,48K all-in-one computer

$2395

ZENITH Z19

$735

TELEVIDEO 920C

$748

ATARI 400 $479

ATARI 800 $769

APF Game Only $95

Complete System $489

MATTEL INTELLIVISION

$229

MONITORS

LEEDEX 12"B&W Video 100

$129

ZENITH 13" Color

$379

SANYO 9"B&WVM4509

$145

SANYO 12" B&W DM5012

$210

SANYO 12"GreenScreen DM5112

$215

SANYO 13" Color DMC6013

$375

APF 9"B&WTVM-10

$120

TELECOMMUNICATIONS

LIVERMORE STAR MODEM 2-year guarantee

$145

UNIVERSAL DATA SYSTEMS UDS-103

$179

D-CAT HARD WIRED DIRECT MODEM

$189

AUTO-CAT Auto Answer, DirectConnec

t Modem

$229

PRINTERS

16K MEMORY UPGRADE KITS 2tor$65 $35

200 ns for TRS-80*, Apple II, (specify): Jumpers $2.50

NEC Spinwriter

Letter Quality High Speed Printer

Includes TRS-80* interface software, quick change print fonts, 55 cps, bidirectional, high resolution plotting, graphing, proportional spacing: R.O. $2395 R.O. with Tractor Feed $2595 KSR with Tractor Feed $2795

C.ITOH Starwriter, 25 CPS, daisy wheel printer $1795

C.ITOH Starwriter II, 45 CPS, daisy wheel printer $1995

Letter quality printers. Use up to 15" paper. 1 year warranty on parts. 3 months on labor. Proportional spacing and bidirectional printing. Same as VISTA V300.

EPSON MX-80 $595

PAPER TIGER IDS 445 Graphics and 2K buffer $699

IDS 460 Bidirectional, 160 cps, graphics and 2K buffer $1050

IDS 560132 Columns, graphics $1599

ANADEX DP-9500/01 $1345 DP-8000 $849

COMMUNICATIONS SOFTWARE

CCI-TELNET VERSION 5: A communication package which enables

microcomputer users to communicate both with large mainframes

and other microcomputers. Completely CP/M compatible. Multiple

communication protocols supported. $149

For fast delivery, send certified checks, money orders or call to arrange direct bank wire transfers. Personal or company checks require two

to three weeks to clear. All prices are mail order only.

dealer (national/international) inquiries invited Send for FREE Catalogue

OKIDATA Microline 80 Friction and pin feed

Tractor Feed, friction, and pin feed

Microline 82 Bidirectional, friction and pin feed

Microline 83 Bidirectional, 120 cps, uses up to 15" paper 779 CENTRONICS TRACTOR FEED PRINTER

Same as Radio Shack line printer I 737 CENTRONICS FRICTION & PIN FEED PRINTER

n x 9 proportional and 7x8 mono spacing.

Same as Radio Shack line printer IV 730 CENTRONICS FRICTION & PIN FEED PRINTER

7x7 matrix Same as Radio Shack line printer II P1 CENTRONICS PRINTER

Same as Radio Shack quick printer EATON LRC 7000 + 64 columns, plain paper TI-810 Faster than Radio Shack line printer III. Parallel and serial

w/TRS-80* interface software w/u&l case & paper tray

Compressed print, vertical form control

ACCESSORIES

SCOTCH HEAD CLEANING DISKETTE: Cleans drive Read/Write head in 30 seconds; specify 5Vi "or8". $

FLOPPY SAVER: Protection for center holes of 5Va" floppy disks. Installation tools and rings for 25 diskettes. $

Re-orders of rings only $ EXTERNAL DATA SEPARATOR: Eliminates data separation problems (crc). Improves reliability. This plug in unit comes fully assembled and tested. $

Z-80 SOFTCARD: Your key to software expansion. The plugin Z-80 Softcard transforms your Apple into a Z-80 while keeping all the benefits of the 6502. Comes with CP/M in two disk format, MBASIC and GBASIC, full documentation and utility programs.

VIDEX BOARD 80 Column, U/L case conversion card CRT FILM: Helps eliminate external glare, 9" RF MODULATOR: Adapts video to TV TRS-80 & OTHER MYSTERIES

NEC SPINWRITER THIMBLE $11.95 RIBBON

CCS CARDS: Parallel or serial printer interface cards RS232: For Radio Shack Interface.

DISK-DRIVE EXTENDER CABLES: Fits all mini-disk drives. SIX (6) PRONG ISOLATOR: ISO-2 AC FILTER/6 PRONG POWER STRIP DISK DRIVE CABLES: 2 drive $29.00 4 drive

DUST COVERS: TRS-80/Apple PLASTIC DISKETTE HOLDER: For ring binder, holds 20

$525 $625 $719 $995 $969

$780

$595

$269

$269

$1589 $1865

25.00

11.95 6.95

29.95

$339.00

$299.00

$ 29.00

$ 29.00

$ 18.95

$ 6.00

$115.00

$ 84.00

16.95

54.00

39.00

35.00

7.95

8.00

The CPU SHOP

TO ORDER CALL TOLL FREE 1-800-343-6522

TWX: 710-348-1796 Massachusetts Residents call 617/242-3361

5 Dexter Row, Dept. B02M Charlestown, Massachusetts 02129 Hours 10AM-6PM (EST) Mon.-Fri. (Sat. till 5)

Technical Information call 617/242-3361 Massachusetts Residents add 5% Sales Tax Tandy Corporation TrademarkTDigital Research

master charge

Circle 270 on inquiry card.

BYTE February 1981 355

MODEL 1200 RS-232 BI-DIRECTIONAL DATA SPLITTER

available In kit form

Model 1200K gives the terminal or microprocessor user a second interface for a printer, plotter, cassette or tape drive. It operates at any speed & isolates the two output devices from each other, while providing 2 RS-232 interfaces from the terminal or microprocessor.

The kit consists of 3 RS-232 connectors, printed circuit board, all necessary components, enclosure, mounting hardware & assembly instructions $69.00

write or call

TERMINAL DATA CDRP.

11878 Coakley Cir.

Rockville, MD 20852

(3011 881 7655

Eleusis and The TI-59

Your TI-59 can now act as God (well, dealer) in the New Eleusis (the card game introduced in the October 1977 Scientific American). The Eleusis-Dealer program randomly chooses a rule then accepts or rejects the cards played.

To obtain magnetic cards for the program, along with documentation, Eleusis instructions, and the latest newsletter, send $6 to

Robert Abbott

Box 1175, General P.O. New York, NY 10116

MAGIC WAND $325

This powerful word processor is in stock for most CP/M compatible systems, including Radio Shack, North Star, Vector Graphics, Cromemco and APPLE [with Z-80 card @ $295 and Videx BO column board @ 8898]. We will custom configure your diskette if you will specify: CPU. terminal, printer.

Our fully interactive

MAIL MAGIC™

mail management software, with 14 user defined fields and full merge and sort capability is available for $149.

We will also quote on all specific hardware and software for APPLE, PET and Vector Graphics.

Computer City ^T

P.O. Box 60284 B ^™

Houston TX 77205 (713) 821-2702

Magic Wand is a registered trademark of

Small Business Applications

Mail Magic is a registered, trademark of

Computer City

Circle 271 on inquiry card.

Circle 272 on inquiry card.

Fine Software Tools in C

The Toolbox

list prints that missing source listing

xref cross reference C programs

sort alphabetize by all or part of text line.

col arrange text in columns on page

print paginates text for hard copy and more

All programs are in portable Whitesmith C xref and list are compatible with the compiler's error listing. Title lines on list and print output includes the date on RT-11 systems Source code on B" floppy and manual available immediately for $45 (tax and shipping included) Specify RT-11 or CP/M format

The Toolsmith

Dept. BYTE

P. O. Box 22511

San Francisco, CA 94122

RT-11 is a trademark of Digital Equipment Corp CP/M is a trademark oi Digital Research

USR-330D Modem

Auto-Dial/Auto Answer S399

Connect your TRS-80, Apple, or any other computer to the phone lines.

• 0-300 Baud-Bell 103/113 compatible

• Serial-RS232

• Half/Full Duplex

• 1 year warranty

FCC Certified Direct connection to phone lines via RJ11C standard extension

phone jack

USR-330A Modem

Same as 330D

but Manual-Originate/Auto-Answer.

Radio Shack Model II Users

We have software to connect you directly to the phone lines.

U.S. ROBOTICS

203 N.WABASH SUITE I7IS CHICAGO, ILL BOBOI

S339

We're the MAGNOLIA people you've been looking for...

Add the CP/M® disk operating system to your Zenith/Heath 'B9 All-in-One Computer'. Easily installed hardware and software proven by reliable service for more than a year. Supports B-inch, double-sided 5-inch, and hard disk drives. Only $195. Askyourlocal dealer; or

MAGNOLIAH

MICROSYSTEMS

2B12 THORNDYKE AVE. WEST SEATTLE. WASHINGTON 9B199

(20612B5-7266

CP/M* is a registered trademark of Digital Research. Inc.

Circle 273 on inquiry card.

Circle 274 on inquiry card.

Circle 275 on inquiry card.

CP/M®+*IBM

CP/M+*DEC

Compatibility with

reformaTTer

Exchange data files with most IBM and DEC equipment through REFORMATTER disk utilities. With REFORMATTER, you can read and write IBM 3740 and DEC RT-11 formatted diskettes on your CP/M system. Programs feature hi-directional data transfer and full directory manipulation. ASCII/EBCDIC conversion provided with CP/M-wIBM.

Each program $195.00 from stock. Specify CP/M**IBM or CP/M--DEC when ordering.

Program Data Sheets and Application Guide available from MicroTech Exports. Inc., ■lb' Hamilton Ave., Suite 2, Palo Alto. CA 94301 □ Tel: 415/324-9114 □ TWX: 910370-745" MUM-ALTOS □ Dealer & OEM discounts available. ^£ 30

C.P/MK is a registered trademark of Digital Research

PRINTERS

NEW BASE, MODEL 850 mi S799OWR PRICE $735

BASE, MODEL 800B mrsmOUR PRICE $585

HEW BASE,/APPLE GRAPHICS

INTERFACE

list uto OUR PRICE $140

OKIDATA 11 LINE 80 mrsiooOUR PRICE $550

■I'liiSl ADD 3 % FOR SSH TO OBOf 8" SfND FOR INfOftrHAJION ON OUR OTKf R PRODUCT 1INFS

I

TECHNICAL INNOVATIONS

P.O. BOX 803 DEPT 82

HILLSB0R0, OR97J23

503-648-6423

I

Circle 276 on inquiry card.

Circle 277 on inquiry card.

6502, Z80, 8080 AND 8085 USERS

JOHN BELL

ENGINEERING'S

6502 AND Z80

MICROCOMPUTERS

ARE DEDICATED COMPUTERS DESIGNED FOR CONTROL FUNCTIONS.

THESE BOARDS FEATURE:

• 2048 BYTES EPROM

• 1024 BYTES RAM

• ALL BOARDS INCLUDE COMPLETE DOCUMENTATION

•50 PIN CONNECTOR INCLUDED IN KITS AND ASSEMBLED UNITS

• 2716 AVAILABLE SEPARATELY

JOHN BELL ENGINEERING'S 6502 MICROCOMPUTER, 2716 EPROM PROGRAMMER AND APPLE II PARALLEL INTERFACE PLUS THE APPLE II MICROCOMPUTER - A COMPLETE DEVELOPMENT SYSTEM.

6502 MICROCOMPUTER FEATURES:

• 1024 BYTES RAM

• 2048 BYTES EPROM

• USES ONE 6522 VIA (DOC. INCL.)

• 2 8 BIT BIDIRECTIONAL I/O PORTS

• 2 16 BIT PROGRAMMABLE TIMER/ COUNTERS

• SERIAL DATA PORT

• LATCHED I/O WITH HANDSHAKING LOGIC

• TTL AND CMOS COMPATIBLE

80-153 BAREBOARD

ASSEMBLED $110.95 $24.95 KIT $ 89.95

JOHN BELL ENGINEERING'S NEW Z80 MICROCOMPUTER FEATURES:

• Z80 CPU SOFTWARE COMPATIBLE WITH Z80, 8080 AND 8085 MICROPROCESSORS

• 2048 BYTES EPROM

• 1024 BYTES RAM

• SINGLE 5V POWER SUPPLY AT 300MA •CLOCK FREQUENCY IS 2MHZ, RC CONTROLLED

• Z80 PIO (DOC. INCL.)

• 2 8 BIT BIDIRECTIONAL I/O PORTS

• LATCHED I/O WITH HANDSHAKING LOGIC

• TTL AND CMOS COMPATIBLE

80-280 BARE BOARD

ASSEMBLED $129.95 $29.95 KIT $119.95

USE YOUR 6502 OR Z80 MICROCOMPUTER TO CONTROL EVERYTHING!

• YOUR HOME SECURITY SYSTEM • AUTOMATIC CONTROL OF VIDEO

• HEAT CONTROL RECORDERS

• LIGHT CONTROL • ROBOT CONTROL

• SOLAR HEATING AND POWER SYSTEMS • AUTOMATIC DIALER

• AUTOMATIC CONTROL OF TAPE • AUTOMATED SLIDE SHOW CONTROL RECORDERS • COMMUNICATION SYSTEMS FOR THE

• TRAFFIC LIGHT CONTROL DISABLED

• IRRIGATION SYSTEMS • THE WORLD

Johiv Bell Eivgiiveeriivg

VISA

ALL PRODUCTS ARE AVAILABLE FROM: JOHN BELL ENGINEERING

P.O. BOX 338 • REDWOOD CITY, CA 94064 • (415)367-1137 ■SEND FOR OUR COMPLETE CATALOG! ADD 6% SALES TAX IN CALIFORNIA. ADD 5% FOR SHIPPING AND HANDLING.

MASTER CHARGE

BYTE February 1981 357

CROSS-ASSEMBLERS

WRITTEN IN ANSI FORTRAN IV

PACKAGE NO. MACH1NEIS)

XASM8800 MC8800,02,08

XA8M8805 MC8806.MC148805

XA8M8809 MC8809

XASM808S 8080.8085

XASM1802 CDP1802

XA8M8602 8500FAMILV

' "Corning soon: 60000,8086, 99D0,ZB00 6800 to 6809 Translator available now.

null instruction set, all addressing modes. Free formal input, relocatable listing end object module, many user selectable assembly options. 8 character labels, arithmetic expressions in operands, long error messages, high execution speed.

Full-capability assemblers run on almost any system supporting ANSI standard FORTRAN IV, 1966 or later, at a fraction ol the cost of a separate development system.

FORTRAN SOURCE MEDIA PRICE

MAGNETIC TAPE PACKAGE SI00,00

PUNCHED CARD PACKAGE S 75.00

MANUAL/LISTING ALONE S 30.00

Packages include manual/listing, shipping in U.S.A. For cards, specify punch code. For tape, specify cotle. BPI, block size.

■ B^ ■■ am Intelligent Devices of Mn

I 1 1% /I P-0. Boi 14530 I II llfl Minneapolis, MN 55414

■ m^mW I W I (612)4270787

ATARI. OWNERS

SCREEN PRINT INTERFACE

Obtain hardcopy of any screen image (graphics and / Of text) on eittier a TRENDCOM 200 or IDS 440 Paper Tiger printer. Simply attach tho supplied parallel printer cable and load the soflwore from cassette (may be transferred to Disk). Obtain a "picture" of the screen on your printer under direct (CTRL?) or program (X10) control. Works in all graphics / text modes as well as LPRINT and LISTMP:" , - 0/N Only $139

Parallel Printer Interface for the

ATARI 400 / 800

Connects to controller jocks 3&4 works with BASIC /DOS/

ASSEMBLER Three printer connectors, available:

ATARI 400/ 800 TRENDCOM 100 / 200 A4P-1 ABP-1 CENTRONICS 730 / 737 A4P-2 ABP-2 CENTRONICS 36 PIN* A4P-3 A8P-3

CA soles add 6% tax MC / VISA accepted.

' Fits all other parallel Centronics plus Anadex. Bose 2. Epson, Comprint and Microtek Order by part number. ATARI is a recognized iiademork of ATARI. Inc.

AMCROTPONICS, inc. ®

1125 N. Golden State Blvd / Suite G

Turlock. CA 95380 (A) (209I 667-2888 / 634-8888

69,

95

BELOW DEALERS COST!

NorthStar

32KDD -2295.00 32 K QUAD-2600.00

North Slat P

s 16 0 00

COD CASH IN ADVANCE VISA/ MASTER CHARGE'

'ADD 4 PERCENT ON CHARGE ORDERS

CUSTOM BUSINESS COMPUTERS

103 ATLANTIC AVENUE. LYNBROOK. NEW YORK l I563.(516l8fl7 33*0

Circle 280 on inquiry card.

Circle 281 on inquiry card.

Circle 282 on inquiry card.

Tired of BASIC? Try S/S PASCAL!

for CP/M* users

• Powerful subset of Standard PASCAL.

■ Integers,Reals,Strings,Text Files,etc

.INTERRACTIVE COMPILER !!

■ Correct your errors during compilation !

■ Your source on disc is compiled in fast efficient Pcode directly stored on disc.

■ Complete and detailed nenual.

■ Tip knowledge of PASCAL required.

SCOTIA SOFTWARE

$65 on cassette

or 5.25" disc

S10 nenual only

1964,Beech St.,Halifax N.s. F33H 4BB , CANAfW

Requirement :24K with CP/M*

CP/M is a Tr^lcmark of Digital Research

6809

FOR YOUR WINTEK BUS

C PU card w ith serial

port6k ROM-1k RAM'

3 chan t im er-DM A

Monitors S ys Bus

B uff ers-M apped

Mem to ,5Mbyte

4.5x6.5" cards

PETRONICS

BOX 2475

W LAFAYETTE IN

47906

Z-80 FORTH $50.00

FORTH is fast, easy to use, extensible, and totally flexible. Excellent (or rapid development of real-time data acquisition or process control applications.

Laboratory Microsystems Z-80 FORTH is an optimized implementation of standard fig-FORTH • to run on Z-80 microcomputers under the CP/M 2.x-- operating system, Unlike the FORTHs of many other vendors, our interpreter uses CP/M compatible random access disk files for screen storage.

Z-80 FORTH is distributed on an eight-inch, sectored, single density diskette containing:

executable interpreter

fig-FORTH portable line editor

screen editor

demonstration programs

utilities

complete documentation

Price: J50.00 includes tax and shipping.

Laboratory Microsystems

4147 Beethoven Street Los Angeles, CA 90066

oft

Circle 283 on inquiry card.

Circle 284 on inquiry card.

Circle 285 on inquiry card.

Floppy Discs $26.00-10

We carry a full line of computer supplies. Send for free catalog.

PO Box 5059 Milford.Ct. 06460

IY1CS

(203)877-3610 Call collect

Visa ■ Master Charge COD Check

LOW COST-HARD COPY

KSR 33 TELETYPEWRITERS

20ma current loop, 110 Baud

$275. each

Send check or money order to:

JHC INFORMATION PRODUCTS

P.O. BOX 2014 ESCONDIDO, C A 92025 U.S.A. ORDERS ONLY CALIF. ADD 6% SALES TAX ADD $10 SHIPPING CHARGES

allow 4 wks. for check to clear, reconditioned • quantity limited

Free

Microprocessor Catalog

40 page catalog of 6800 single board computers, interface modules, SPRINT 68 control computer/ development system, WIZRD multitasking DOS, '"—,. BASIC, cross assemblers, cross ............jrs. custom engineering, OEM applications

software.

IWintekCorp. 1801 South Sir Lafayette. IN 47904 317-742-8428

Circle 286 on inquiry card.

Circle 287 on inquiry card.

Circle 288 on inquiry card.

AVA

The Supermarket for TRS-80 Add-on Components

In stock now. Immediate delivery.

81 Vista Compi Catalog Write for Yours Today, 1401 BochardSt. (and other computers, too) ^B

9270E

'

The Vista V-80/800/8000 Family Disk Drive System

Fully compatible with TRS-80, Heath/Zenith i 120 Day Warranty 40 Track Patch at NO CHARGE

V-80 Single drive system (102K) S 395.00

V-80 Two drive system (204K) $ 770.00

V-800 Single drive, B52 Drive (204K) S 595.00

V-800-2 Double drive, B52 Drives (408K) .. S1175.00

V-8000 Single drive, B92 Drive (408K) .... S 775.00

V-8000-2 Double drive B92 Drives (816K) . S1450.00

The VISTA Model II

• Provides one, two or three drives

• Adds up to 1.5 million bytes of on-line storage

• 120 day warranty

• Does everthing Radio Shack's expansion system will do...for less!

nj

$ 900.00 Single drive (non-expandable) S1000.00 Single drive

Expansion System S1550.00 Two drive Expansion System S2100.00 Three drive Expansion System S 525.00 Additional drives alone

Vista's Add on Drives for Apple"

Speed . Capacity . Price More for Less

• 30 to 60% cheaper per byte

• From 20 to 400% more capacity

• Twice as fast

• Compatible with Pascal

• Warranty 120 days

40-Track 80-Track 160-Track Controller

$365.00 $595.00 $825.00 $150.00

The Vista MUSIC MACHINE 9

WITH 9 VOICES!

! :

NEW! Uses latest State of the Art LSI Technology. » Requires only one slot for 9 voices!

Uses three Ay3-8910's to produce nine voices

(Othercompetitive models have only 3 voices). i Simulates three ALF Boards. » Plays music generated by the ALF Board. • APPLE'" II compatible.

ALF"* software required.

$129.95

Vista V300

Daisy wheel Letter quality

Base 2 Printer

Variable line spacing control 0 to 64 dots in half dot increments 100 cps — six densities Standard 96 character ASCII Up to 10 character fonts

Vista Printer

5 x 7 dot matrix 80 column (125 cps)

Printers

$1895.00

$575.00 (includes: 2-K Buffer, graphics high speed tractor feed)

Siemens

Shugart

Add On Drives

40 Track, Double

Density-204K

Dual Head, Double

Density-408K

FDD 100-5 40 Track Double

Density 204K

FDD 100-8 8" Single

Sided Drive

801R Single Sided Drive

$375.00

$448.00 $448.00

Other Products

VISTA Verbatim diskettes (hard or soft sector) Certified

40 track

16K RAM upgrade kits, guaranteed for 120 days.

PRIME PRODUCT

NEW DOS +

LNW expansion bare board

H.C. Pennington book, TRS-80 Disk and Other

Mysteries

DDT Disco-Tech disk drive timer

S 38.95

S 59.95

$110.00

$66.95

$ 18.95

$ 19.95

The VISTA V-200 for Exidy

Completely packaged system, tested and ready to plug in, includes: power supply, two 40 track drives, case, controller, all cabling and total CP/M™ documentation. Storage capacity from 400K to 1.2 meg.

System software-VISTA CP/M Disk Operating System and BASIC-E Compiler recorded on 5-1/4" diskettes. Price: Starting as low as $1199.00

CALL TOLL-FREE 800-854-8017

(For Orders Only) All request for catalogs must be by mail

Price: Starting as

232

The Vista Computer Company 1401 Borchard Street • Santa Ana, California 92705

"TRS-80 is a registered trademark of Radio Shack ■CPM is a registered trademark of Digital Research

Circle 289 on inquiry card.

BYTE Febniary 1981

359

Q.T. Components From SLUDER

Assembled & Tested QT S6C-2/4 MHz QTZ80-A REV I 2/4MHI Ram 16 16K sialic 2/4 MH* Expandable + Dynamic 64K Ram 65 16K static Bank Sel Silence + Mother Boards

12 slot

1 B slot

Mainframe + with p/s

Mainframe + withdual 5% cab

Mainframe + with dual 8 cab

For Mainframe + and mother boards

add mother board price from above QT

In/Out board Serial & Par

Clock Calendar with 2 mo. battery 8.-U

f or S-1 00 or Apple Computer or Radio

Shack TRS-80

CCS Disk Controller with CPM

Single 8" Disk Cab. w/ps

Shugarl 8" SA801 R while supplies last

MPI 654 Disk Drive 851

Q.T. Computer Systems Computers

SYS +SS 8" ss drives

SYS +DS 8" ds drives QT Mini-system ss 5'A drives

Mini-system ds 5% drives 4116 200ns rams 16K 8 pes

Make cashiers checks, certified checks. ■ payable to SLUDER. PO Box 9 51. Wi Call 714-895-1 746 9 to 5 Pacific Time M minimums: $2.00, $5.00 on floppys & mai systems. Ca. res. add 6% sales tax. CPM ■: Digital Research. Prices subject to change.

List

Sa:e

1>H()

225.

?1<]

175.

?1(]

175.

67S

525.

■//a

230.

50

45.

/()

60.

90

75.

140

120.

3B0

2B5.

40(1

325.

b /b

475.

1 50 400 1 75. 499. 295

4250. 4995 2495. 2795.

1 25. 325 I 50. 380. 250.

3750. 4450. 2120. 2375.

CA. 92683 F Postage ■nes. SI 5.00 c ademark of

Circle 290 on inquiry card.

APPLE DISKS

MULTIPLE PROGRAMS PER DISK

BASIC TUTOR PHY~.„

BAb ASTRONOMY S,CS

SPANISH HANGMAN

Comp°s/t,on

Quality Software & Courseware designed for School & Home Educational Users

Discover the values of the computer as an instructional aid

Send Now For Our Catalog TO:

!= !*!!#* AT lOf tUl

^^!!|i^^!|!d|||P

3Noppa Lane, Westport, CT 06880

SOFTWARE DESIGN ENGINEER

BSEE/BSCS. minimum 3 years programming experience. Realtime systems programming and software development for electronic switches is a plus. Experience with PASCAL or C or Assembly language required. Call collect or send resume to Kenneth W. Cooper, Harris Corporation, RF Communications Division, 1680 University Avenue, Rochester, NY 14610, (716) 244-5830, EXT 3356.

HARRIS

An Equal Opportunity Employer M/F

-ywivi.

Circle 291 on inquiry card.

IS YOUR

Worth Star OUT OF SORTS?

INCREASE YOUR BASICS SORTING POWER OVER 1800%!

N+SORT is easy to use and will perform sorts on one and two dimensional or string arrays using optional sort keys. For example, to alphabetize AS:

10 A$ = "ZYXWVUTS"\ REM Define String 20SRTA$,LEN(A$).1\ REM Sort A$

N+SORT interfaces to any release 4 or later North Star Basic and can be yours for only (ton

vJ>Oy plus$1.50 shipping Calif. Res. add 6% tax. Send check VISA or WI C j+im- Complete Brochure Available

\5Z) Software Systems

1269 Rubio Vista Road, Altadena, Calif. 91001 (213) 791-3202

r~ QUARTZ CRYSTALS **$

1 ) .JZ1B-B

5.2429 B

993 361

20O00-B 362886 8

42J5IB-B

46B12BB |

I 52% 8

5.GI0-B

9 9840 8 B

2D.49BSB 36.3636-B

42B768B

4737688 ' .

, ' i.OOl) *

5.71438

998960 B

22.11048 37962B-B

42.9Z58B

478B3BB (

1 1.843! A

S.9S5-B

lO.OOO B

22.62SBB 3B.376BB

42.962BB

4B.000B .

! | 1.8437 B

5.9828

I0.245BB

2635S6B 384448 B

43D006-B

4B3006B '

< 20QOA

GDOOB

10.49GB-B

26.50O6B 38625BB

4303788

48666B B ' .

.' 20971 A

6.144 8

10.7755 B

26.6706B 38S25BB

43074BB

4B.7006B < '

' > 2.457E-*

G.I5D3D-B

iiutss-a

?70O0 B 39.3128-B

43.1B5SB

4BB76B 8

\ 2.W0-A

G.29780B

IOI3U-B

21DUK, B 39 5038-8

432MB-B

49 70068 '|

, ' 2.66SJ-B

6.400 B

II 13608

276506-B 396958-B

43 3338-8

4973388 1

1 2.99M-B

655 36B

11.155 8

ZB 4006,0 39.753AB

43 3708 B

498128 B , '

1 l 3 mo *

6.72530B

II2I86B

28.6276 B 398768 B

43407BB

SO 250 5 B |

| 3.067 B

6.75B40B

112890 B

2B.7538B 395628 B

43.4378 B

5liJ556 B ' .

. r 3JO0-B

6.9003 -B

11.4776 B

29B75BB 40444B-B

43.444BB

5I3I2BB |

1 | 32768 A

7.D063B

11.6566-B

299378B 40L9ZBB

43655BB

51777B B . 1

t 3.50D B

7.0336 B

116816B

300648B 40.B12B 8

43 6298B

5IB506B ' |

( ' 3.579 B

70916 B

12.440 B

30.3606B 40B336B

436668 B

52B12BB 1

1 4 000 B

7.1836 B

14.31B2B

30625BB 40.B75BB

43.7778 B

56.7506 B , '

' . 4 1943 B

7.25B6B

14 430BB

30B76BB 40.B88BB

43.B12B-B

60 6006 B 1

| 4 34ZG-B

B.000-B

15.000 B

3I.437BB 40.925B-B

43.8148 B

60.7508 8 ' |

. r 4 4803-B

B.D556 B

I5 440BB

3I.753BB 41.0008-8

43.B5188

667S06B i

', 4EI03B

BJ4IB-B

15.5066 B

319006-6 41.16668

43BB88B

704006 B . '

1 46503 B

B.1B1BB

15.000 B

32.000 B 4I.3768B

43925BB

750005B |

, ' 48303 8

B.3303-B

16.36488

332Q06B 4193736

44.0006-8

908338 B ' .

► 4.9IS2-B

8.4938 B

172246 8

33 6A8B 42 BOOB 6

44B37B-B

99.96648 |

I 1 SHOO B

B 5766 B

17 2422 8

34 5558 8 42.5836 B

44.376BB

1006668 B A

| 5D6G8 B

18JW0-B

34 7538 B 42.6268 B

44.7778 8

1014668 B )

. ' 5 I2D3 B

B.960S B

1B432DB

349776B 42.70OG-B

45.I756B

103 0668 B 1

') S IBSO B

B9906 B

1946B0B

359256B 42 7538-8

463006- B

103 4668 B , '

1 5IBM-6

94720B8

197S0B B

360008 42B148B

46.7006-8

104.9918 B r

( ALL A

12.99

AL

B -11.99

OOfl MORE DEDUCT 5". ' 1

ADD $

.00 SHIPPING

CAL.

RES. ADD 6% SALES TAX

FREE OSCILLATOR SCHEMATICS

WITH ANY ORDER

l! QUALITY COMPUTER

PARTS J

l( P.O.

BOX 743 / CHATSWORTH

, CA 91311 S

Circle 292 on inquiry card.

EVERY MONTH

BUY, SELL OR TRADE ALL TYPES OF COMPUTER EQUIPMENT AND SOFTWARE (pre-owned and new) among 20,000 readers nationwide in BIG (11x14") pages. Classified ads are only 10* per word and are indexed for easy and fast location. Subscription: $10 a year/12 issues. Money back guarantee. Sample copy, $1.50. CdfTlPL'TaR SHQPPSR P.O. Box F-14 Titusville, FL 32780 (305) 269-3211 MasterCard or VISA subscription orders only, call TOLL FREE 1 800 528 6050 Ex. 184 .

Circle 293 on inquiry card.

Circle 294 on inquiry card.

Circle 295 o n inquiry card.

80X24 VIDEOTERM™

7X9 MATRIX DISPLAY FOR

LOWER CASE WI DESCENDERS Hi Y L t II

TflUS

80 columns by 24 lines with easy to read 7x9 dot matrix, upper and lower case with descenders using shift lock feature • l K firmware incorporates PASCAL and BASIC protocalls so user is not required to enter machine language programs or change PASCALS. Misc. info, or Gotoxy files • Compatible with all APPLE II peripherals so user won't need new software patches for luture software products • Crystal controlled dot clock for excellentcharacterstability • VIDEOTERM is the same size as the Apple language card and power consumption is held to a minimum through the use of CMOS and lower power devices • Character set can be user definable up to a maximum of 128 symbols of 8x16 dot matrix font • Display control character mode and four standard display formats controlled by escape sequences • Built in light pen capability ■ Inverse display mode • 50/60 HZ operation- Sockets on all IC's.

r*

ind VIDEOTERI

(M $19 ^3

rollts. OR 97J30 Phons 1503) 750-0521

SpecialOffer! Limited Time!

OWNERS 0fTRS-80Tlevelii,i6k

DERBYn

Outstanding game of racing designed by 0 scientist and statistician. Six mutual probability algorithms precisely coded (not just RNO). Every race a cliffhanger. Bet to win place, or show; perfectos; trifectas! Photo finishes! Inquiries! Play different odds every race! Can be beaten with a lot of skill. 1 to 5 players, plus a tout who bets every race using exactly the same handicapping information you have (he will even place 0 bet for you-for a fee of course). Excellent spot graphics for realistic motion.

CAN YOU BEATtheTOUT

ORDER NOW for one of the most

remarkable games you'll ever play. Only 115.00 (check or m.o.) for qual. cassette. Add $.50 postage, handling. FL res. add 4% tax.

C8A ASSOCIATES,Inc.

P.O. Box 2 36 2

Satellite Beach, FL 32937

OSBORNE FOR SUPERBRAIN

General Ledger $125

Accounts Payable.... $125 Accounts Receivable ... $150 G/Lor A/PR Manuals... $20ea C-Basic-2(Required). ..$110

All features described in the Osborne and Assoc, manuals are fully implemented, additional features fully documented. ON DISKETTES, YOU GET:

- Basic language "source code"

- Compiled programs with data files - ready to run.

EXTRAS:

1. Additional documentation included.

2. G/L accounts posted by A/P and A/R programs are operator accessable.

3. No source code changes required.

4. A/R handles discounts.bothsalesand term, and features expanded reports.

JEFF JORDAN, MBA

Management Consultant

Route 3, Box 285

Sandpoint, ID. 83864

(208) 263-8365

Circle 296 on inquiry card.

Circle 297 on inquiry card.

Circle 298 on inquiry card.

Mo

Dual Trace Oscilloscope HITACHI 30 MHz

• TV sync-separater circuit

• High-sensitivity ImV/div (6 MHz)

9 Sweep-time magnifier (10 times)

• Z-axis input (Intensity modulation)

• Signal delay line

I. m ; • X-Y operation " - f^i • Trace Rotation

w ^ >^_..Sf'] Model V302B

—S5^ $995

ra sensitive to your input

PORTABLE thandar OSCILLOSCOPE

Model SC110 °-V'

Only S369

ULTRA LOW

POWER

CONSUMPTION

• AUTOMATIC CIRCUIT

POWER DOWN FOR

UNUSED SECTIONS

MAILORDER:

P.O. BOX 2208Y CULVER CITY. CA 90230 PHONE ORDERS (213) 641-4064

Minimum Ofdei S10.00. Add S2 00 lo cover postage and handling Maslei Chaige and VISA welcomed. Please include your ctiaroe card number, interbank number and expiration date

HICKOK DIGITAL MULTIMETERS LX-303

S7495

S8995

DMM +

VARI-PITCH +

LOGI-TRAK = MX-333

s235

8080A

PROCESSOR

Sr60

EPROM

2708

S890

2716

(5 Voll) SQ90

2114L

(450 nS)

4116

(200 nS)

POWER SUPPLY

'olt 3 Amp APS 5-3

S42.50 S40.65 S38 85

CRT CONTROLLER

5037P s35°°

25 UP S25.00 100 up S1900

MOTOROLA

UC6800P UC6B01 LI UC6B02P

yceaoap yceaogp

1222 45.39

«33

MC6S60P MC6B6JP MC6B75L

MC6BB7P MC6888P MC6889P

KTM-3

KEYBOARD TERMINAL MODULE

leariy-lL.-use tcimin. 1(01 The dual mi highly cosl etfeclrv pioviilini) more lea

I Syncrtek Systems

The

aujuo

■nii grca! Mii.itiiliii :s used ta<lay

display

and absolute and re] KTM-3 2d x 40 c KTM-3/80 24 x £

3 H

* 10% *

DISCOUNT

COUPON

Bring this l'IM"I*0\ into one of our stores or

mail to our Mail Order address shown below

and receive a I 0% IMSt <M \T

on purchases from this Ad of $50.00 or more.

OkkVr i;\i*IHi:S on I Yhrii.irv2it. I UU I

NAME

ADDRESS

CITY, .. STATE

ZIP ... PHONE NO

Coupons accepted only Willi lull name and address filled

!■>.

VISIT A STORE NEAR YOU T0"AY - We stock a large selection of Technical Boohs, Discrete Components. Integrated Circuits. Test Equipment and Electronic Supplies.

ATLANTA

3330 Piedmont Rd. N.E

Atlanta, GA 30305

(404) 261-7100

CULVER CITY

11080 Jefferson Blvd.

Culver City. CA 90230

(213) 390-3595

HOUSTON

2649 Richmond

Houston, TX 77098

(713] 529-3489

PORTLAND

1125 N.E. 82nd Ave.

Portland, OR 97220

(503) 254-5541

SANTA ANA

1300 E. Edinger Ave.

Santa Ana, CA 92705

(714) 547-8424

SUNNYVALE

1054 E. El Camino Real

Sunnyvale, CA 94087

(408) 243-4121

TUCSON

4518 E. Broadway

Tucson, AZ 8571 1

(602) 881-2348

SAVE! SAVE! SAVE!

TRS~80's

We have discounts, free shipping and a TOLL FREE NUMBER available

Call Us! 800/531-7466

Pan American Electronics

Microcomputers

INCORPORATED

Dept. B

1117 Conway, Mission, Texas 78572

TOLL FREE ORDER NUMBER 800/531-7466

Texas & Principal Number 512/581-2765

Telex Number 767339

Radio /hack

AUTHORIZED SAI I s ("I NTLK

MottwrCcvd

Circle 300 on inquiry card.

BYTE February 1981

361

add lowercase with our PLUG-IN piggyback board

CEnTRDniC5

NOW! Add lowercase and optional second character sets to ALL MODELS* including the popular 101A & 779; 96 character ASCII; optional character sets (add $15.00) include APL, TRS-80/H-19 Graphics, Scientific and Customer Defined.

•Except 730. 737 and 6000 Series 5 x 7 dot matrix — $ 95.00 (A&T) 9 x 7 dot matrix — $135.00 (A&T)

Postage Paid on Prepaid Order

All products waranleed 90 days MasterCard. VISA. Check. MO. PO

Digital Systems

Engineering

12503 King's Lake Drive

Reston, Virginia 22091

(703) 620-2994

Circle 301 on inquiry card.

MEMOREX

Floppy Discs

Lowest prices. WE WILL NOT BE UNDERSOLD!! Buy any

quantity 1-1000. Visa. Mastercharge accepted. Call free (800)235-4137 for prices and information. All orders sent postage paid.

PACIFIC EXCHANGES

100 Foothill Blvd San Luis Obispo. CA 93401. (InCal. call (805)543-1037)

c 6

ro OJ =J

— u a

Sales Insta Servi

0

Com

0

<i

¥

n

o

§■ "is

Li

o

LL 0

0

Gro

oorated Street ds, Ml

01

CO

CO

co

.0, in

£

w

E

z s*s

H

CD

O

0

h

<^c

fl

CD

□

01

u

EPS

418 Granc

H

CO

0

D

I)

r *->

-)

HI

<

%

1 Li

f A

«

1 A.

tf=h

8)

-■sU

u.

LI

*

[

M

h .

Circle 302 on inquiry card.

FIFTY BUS SYSTEMS

32K 6800s from $1694.59

32K 6809s from $1844.69

Include: Chassis, CPU, 32K Static Ram, l/Os Fully Expandable

2114L 300ns STATIC RAM CHIPS . S5.90

PflPTflPV PRIMP From ihe same shipment we use in our TMUIunT rnimc professional quality boards. Add $5.00 Handling on Orders Under 5200.00

32K STATIC RAM BOARD

FORTHESS50ANDSS50C BUS (SWTP etc.)

• SS50C Extended Addressing (can be disabled).

• 4 separate 8K blocks • Low power 2114L RAMS

• Sockeled lor 32K ■ Write Prolecl

• Gold Bus Connectors

16K $328.12

24K $438.14

32K $548.15

Phone, write, or See your dealer tor details and prices on our broad range ot Boards and Systems tor the SS50/SS50C BUS Including our UNIQUE 80x24 VIDEO BOARD, and our AC Power Conlrol Products loi all computers.

Gimix <51

1337 W. 37th Place ■ Chicago, IL 60609 (312)927-5510 ■ TWX 910-221-4055

The Company that delivers.

Quality Electronic products since 1975.

GIMIX® ana GH0S1S are Registered Trademarks oi GIMIX INC

JOY-6

THE ULTIMATE JOYSTICK INTERFACE FOR YOUR TRS-80*

JOY-6 Is a Complete 6 Channel, 9 Bit A to D Featuring:

■ 4 channels with variable gain—(or Joysticks

■ 2 unbuffered channels—lor game paddles, sensors

■ 3 digital inputs—lor pushbuttons. TTL signals

■ Sound effects capability—(user supplies speaker)

■ Comprehensive users manual—write your own games!

■ Joypak-1 cassette- (Requires 16K level2)-6 exciting Joystick games wilh sound effects, including:

KEtffl,

A unique new game of slrategy and skill. Time shots and judge angles correctly to deleat the opponent. Use the pushbutton to spin your shots. Practice mode sharpens your offensive and defensive tactics. Variable levels of difficulty.

SPECIAL IKTR0DUCTDRT OFFER! jof-e compete wan i joysticks WITHPUSHBU7TONS, JOYPAK I. POWER SUPPLY.USEP.SMANUAL ASSEMBLEO. TESTEO.PEAOY TOPLAY 0NLy $99.95

mEGfl

systems inc.

PHONE 0HDEHS WELCOME 215-337-3876

COO . CHECK. M O MC .VISA

Circle 303 on inquiry card.

23 MEGABYTES 54495

--■DCS S33H.irJ D;*c 5ub\V.ti-- Jntlurii-, JV-.B liinfor-^led

.it i I .) DlSfOS . .".CiS "SIQrj Conlrol I i-r , t.it.l.'i .ind CBI0S

CP- 2.2 . ■ ■'■•' <>■.-■ r u .p|. .,..,; .j- in 3 MnrJicr,

ADAPTIVE DATA t» ENERGY SYSTEMS 2G27 Pomona Boulevard, Pomona, California 91768 .ill (714) 5 94-S8S8 .. i !»if,iv<. 10'00 id '.00 ''.S.r.

PS rOO S (OO Bus Hard Disc Controller J695 S33 33MB Disc Controllar Subsystem S4495 SIO WMB Disc Subsystem 13495

■H It ■ iigiittrid DEALER INQUIRIES WELCOMED

Circle 304 on inquiry card.

Circle 305 on inquiry card.

Circle 306 on inquiry card.

STEPPER MOTOR/ DRIVER BOARD

Interface your computer to

the REAL world

Indispensable for Robotics

Many control applications

Each pulse from your computer steps

the motor 7.3° Features:

■ Norlh Anwrican Philips K82701-P2 type Stepper motor

• SAA 1027 Stepper motor control I.C

• Optically isolated

• 12 VDC operation

• All I.C.'s socketed

• Computer controls direction of rotation, 7.5° per step

PRICE

Complete DRIVER ASSEMBLY, incl. all

I C.'s. assembled and tested {does not include

motor) $39.95

STEPPER MOTOR $28.95

SAA 1027 Driver chip only $16.50

Data, schematics are included

Terms. Check or moneyorder U.S. funds only UPS

shipping and handling included (NY. slate residents

add 7">. salts lax) Immediate delivery from Slock All

nems gudranifL'd

SURPLUS ELECTRONICS

ASCII

ASCII

TRS-80* COMPATIBLE, IBM SELECTRIC® -BASED I/O TERMINAL

with ASCII conversion installed: $645.00

Many Other Items Available: Tape Drives; Cable; Cassette Drives; Wire; Power Supplies (5 volt 35 amp, others); Displays; Cabinets; Transformers; Heat Sinks; Printers; Components.

Send tor Free Catalog

WORLDWIDE ELECTRONICS, INC.

130 Northeastern Blvd.

Nashua, N.H. 03062

Phone orders accepted using VISA or MC

Toll Free 1-800-258-1036

in NH 603-889-7661

'TRS-80 is a trademark of the Radio Shack

Division ot Tandy Corporation.

16K STATIC MEMORY

"UNISELECT"

200 ns Memoiy Chips, A&T. Guaranteed S235.00

Fully Static - 2114L2. NO DMA restrictions S 100 Bus - Meets IEEE-S100 Standard SW address, bank select in 16K block phantom, socketed gold contactsBank Select - by SW sellable port & bit. compatible with CROMEMCO, NORTH STAR. ALPHA MICRO, etc. Guarantee - One lull year. Check. MC. Visa or COD (S4 fee). Stock to 72 hour delivery. Illinois residents add 5'/*% tax Other • S 100 Boards available

S. C. DIGITAL

P.O. Box 906, Aurora, IL 60507 Phone: (312) 897-7749

Circle 307 on inquiry card.

Circle 308 on inquiry card.

Circle 309 on inquiry card.

Circle 310 on inquiry card.

CM

CM

*

Yes! We supply

IMSAI

——v

compatible products...

NOTE: "Original" IMSAI parts were purchased at the closing business sale of IMSAI Manufacturing Corp. WW Components also distributes S-100 buss IMSAI compatible parts and boards. As supplies of "original" parts are exhausted, WW reserves the right to supply equivalent compatible parts notmadeby IMSAI.All items listed as "Assembled & Tested" have been assembled by WW Components and carry a 1 year warranty.

IKB-1 Intelligent keyboard with full ASCII character set, both serial and parallel outputs,

+ 5VDC operation, 8035 processor and fully programmable keyboard.

Assembled & Tested S149.50

D10 Disk Controller works with most 8" or 5Vt" drives. NO LSI controller chip used!

All operations/specifications firmware controlled. Works with IMDOS or CP/IVT 2.2

Two Board Set. Assembled & Tested (Specify 8" or5 'A ") $350.00

VDP-40 Desk-top 8085 micro-computer system with keyboard, 9" CRT display, 10 slot

S-100 board, disk controller, 64K dynamic RAM, 2 ea. TAND0N 5'A" disk drives, 28 amp power supply.

Assembled & Tested $2895.00

1-8015 Complete System w/MPU-B

CP/M®2.2

The complete 8085 system, includes MPU-B, RAM III, 10 slot terminated motherboard, PS-28D, and jump start front panel. A complete G4K system!

Assembled & Tested $1250.00

NOW AVAILABLE - CP/M for the IMSAI floppy disk system. Version 2.2 is for IMSAI available for the DI0-C 8" controller. Others on request. Docs. incl.

8" Diskette & Manuals $175.00

Ask about documentation, repair service, firmware and software for your system.

TERMS: ID PREPAID Send check or M.O. for merchandise amount only - we pay the shipping. (2) UPS COD or bankcard orders by phone or mail - shipping charges added. California Residents add 6.5% Sales Tax.

UJ DC

s

CO

cc

o

55

o B!

s

IS

I

BUILD YOUR OWN LOW COST MICRO-COMPUTER

POWER SUPPLIES

FOR S-100 BUS, FLOPPY DISKS, ETC.

POWER TRANSFORMERS (with mounting brackets)

ITEM NO.

USED IN KIT NO.

PRI. WINDING TAPS

SECONDARY WINDING OUTPUTS 2x8 Vac 2x14 Vac 2 x 24 Vac

SIZE WxDxH

UNIT PRICE

t

T5

0V,110V,120V 0 V, 110V, 120V 0V, 110V, 120V 0V, 110V, 120V 0V, 110V, 120V

2X7.5A

2X12.5A

2x9A

2x4A

2x4A

2X2.5A 2 X 3.5A 2X2.5A (28V, CT) 2x2A

2X2.5A 48V, CT, @3A

33/4 3»/4

3%

3V<

3'

' x 3%" x 3/„" ' X 4%" X 3/„" ' X 4%" X 3/„" ' x 3%" x 3/„" x3"X2'/2"

POWER SUPPLY KITS (open frame with base plate, 3 hrs. assy, time)

ITEM USED FOR @ + 8 Vdc @ - 9 Vdc @ + 16 Vdc @-16Vdc m + 28 Vdc

SIZE Wx Dx J

21.95 27.95 29.95 22.95 14.95

UNIT PRICE

KIT 1 15 CARDS SOURCE 15A

KIT 2 SYSTEM SOURCE 25A

KIT 3 DISK SYSTEM 15A

1A

2.5A 3A 2A

2.5A 3A

2A

4A

12'

12'

14'

X5"X4/B" X 5" X 4'/," X6"X4'/,"

52.95 59.95 67.95

ASSY. & TESTED, OPEN FRAME, SIZE 10"(W) X 6"(D) X 4'/„"(H) 92.95

DISK SYSTEM PWR SUPPLY "S3

UNREGULATED OUTPUTS: +8V@15A, ± 16V@3A

REGULATED OUTPUTS: + 5V@3A, - 5V@1A, + 24V@4A, SHORTS PROTECT. IDEAL FOR THE SYSTEM WITH 12 SLOTS MAINFRAME & TWO 8" DISK

DRIVES, SUCH AS SHUGART801R OR SIEMANS FDD 100-8. (OPTION: OVP for +5V © ADD $5.00)

DISK DRIVE POWER SUPPLY "R3" assy. & tested, open frame,size:9-(W)x6%"(djx 4%-<h) 67.95

SPECS: +5V @ 5A REGUL, OVP, - 5V @ 1A REG., +24 @ 5A REG., SHORTS PROTECT. OPTIONS: 1. REPLACE + 24V BY + 12V

2. ADD ± 12V @ 1A, $10.00 MORE. IDEAL FOR 2 SHUGART 801/851 OR SIEMANS FDD 100-8/200-8 DISK DRIVES & ROCKWELL AIM-65. SHIPPING FOR EACH TRANSFORMER: $4.75. FOR EACH POWER SUPPLY: $5.00 IN CALIF. $7.00 IN OTHER STATES. CALIF. RESIDENTS ADD 6% SALES TAX. OEM WELCOME

MAILING ADDRESS: P.O. BOX 4296 TORRANCE, CA 90510

SUNNY INTERNATIONAL shipping address: (TRANSFORMERS MANUFACTURER) torranCE^CA90502AVE (213) 328-2425 MON-SAT 9-6

Circle 311 on inquiry card.

BYTE February 1981

363

<*

COMPUTER SYSTEMS | INC.

15620 South Ingle wood Avenue Lawndale, California 90260 (213| 970-0952

PLACE ORDERS TOIL FREE

1-800-421-5150

(CONTINENTAL U.S. ONLY)

(EXCEPT CALIFORNIA)

Retail Store Open

10:00 A.M. to 6:00 P.M.

Daily Except Sunday

QT CATALOG NOW AVAILABLE

THE GREAT Q.T. BOARD SET SALE

6 SLOT MOTHER BOARD KIT FREE WITH EACH BOARD SET PURCHASED

Q.T. BD SET #1 (KIT)

FOR

S.D. BD SET #1 (KIT)

FOR SERIOUS

Z+80 CPU (Rev I)

STAF

SBC-100

HOBBYISTS

Expandable + with 32K

Our

Expandoram I with 32K RAM

Our

Monitor For Serial Terminal

Normal Retail

$525.00

Versafloppy I

Monitor For Serial Terminal

BIOS for 8" or 5V»" Drives

Normal $1195.00 Retail Y Q T

Price

$425.00

Price $925.00

Q.T. BD SET #2 (KIT)

FOR

S.D. BD SET #2 (KIT) FOR SMALL BUSINESSES

SBC+ 2/4 Kit (Z80 4MHz)

HOBBYISTS

SBC-200 & SOFTWARE DEVELOPERS

Expandable + with 64K

Our

Expandoram II with 32K RAM

Our

2422A CCS Dbl Den Controller A&T

Normal

$1250.00

Versafloppy II

Normal $1395.00

with CP/M

Monitor For Serial Terminal

Retail

Monitor For Serial Terminal

Q.T. Price

$900.00

BIOS for Disk Drives

Pr'ile $1100.00

>

I

I

I

QT MEMORY EXPANSION KITS

for

TRS-80* APPLE • EXIDY

4116 200 ns 8 for $32.00

2716 (5V-450 ns) $ 9.00

2716 (5 & 12V-450 ns) $ 9.00

2732 (5V) $40.00

2114L 300 ns 8 for $36.00

100 - $3.50 ea.

KASETTE LIBRARY

CAS-10-8 8" Diskette Holder Blue/Grey/Beige/Black . $4.50 or 3/$11.00 CAS-10-5 5" Diskette Holder Blue/Grey/Beige/Black .. $4.25 or 3/10.00^

PRINTERS

DP-9501 - Anadex

9x11 dot matrtx. 220 column. 200 cps & graphics

ADX-9501 Standard DP-9501 ..$1475.00 ADX-9501Gwith graphics & 2K $1525.00

EPSON MX-80 $600.00

LP-80 - Matchless

9x7 matrix..132 column. 125 cps, bi-directional

MAT-MS204 $695.00

SPINWRITER - NEC

65 cps. bi-directional, letter quality with tractor/

serial or par.

NEC-5510 with 2K buffer $2600.00

NOVATION CAT

300 baud, auto answer/originate acoustic modem

NOV-CAT $149.00

WE ACCEPT

MASTER CHARGE

VISA & AMERICAN

EXPRESS

SPECIAL

SINGLE BOARD COMPUTER

4 MHz Z80A CPU. dbl den Controller (5%" or 8" simultaneously), CP/M* compatible, on-bd EPROM/RAM/ ROM, two serial & two parallel ports, real time elk, std 2K monitor & disk routine on ROM, one year warranty. SPECIAL PRICE

TLT-FDC-1 (A&T only) $795.00

DOUBLE DENSITY CONTROLLER Controls up to 4 mini or 4 maxi drives simultaneously, IBM diskette format, works with sgl or dbl sided drives, 1K RAM data buffer, works with any CPU regardless of clock speed, CP/M® 2.2 furnished for 5V<" or 8", Oasis compatible. TLT-FDC II (A&T only) $390.00

/I

>

QT MINI-SYSTEMS

• (4 MHz) Z80A CPU • Dbl Den Controller

• Two serial & two parallel ports • Real time clock • 2K Monitor on ROM • 48K Memory board • Mainframe with 6 slot mother board • DOS on 5'A" disk w/manuals.

QT Mini-System I (V4 Megabyte) $2195.00 Two B-51 sgl sided/dbl den drives

QT Mini-System II (1 Megabyte) $2495.00 Includes two B-52 dbl sided/dbl den drives

(Just add terminal & compute)

CONNECTORS

<

RS232 Set $7.50

1 Male DB-25,1 Female DB-25, 1 Cover

DB25P $3.25

DB25S $4.25

Cover $1.50

S-100 (IMSAI STYLE) $3.00 ea.

Place Orders Toll Free 1-800-421-5150 (Continental US Only — Except Calif.)

Circle 312 on inquiry card.

>

PARTS

MICROPROCESSORS

Z80 (2MHz) ... $10.95 280A (4MHz) . . $12.95

6502 $11.25

6800 $12.50

6802 $18.00

8035 $20.00

8080A $ 3.50

8085A $20.00

8086-4 $60.00

8088 $60.00

8748 $60.00

TMS 9900 JL . . $29.95

8080A SUPPORT

8212 $ 3.50

8214 $ 4.50

8216 $ 2.95

8224 $ 4.00

8228 $ 6.00

8238 $ 6.00

8243 $ 5.00

8251 $ 7.00

8253 $19.00

8253-5 $20.25

8255 $ 6.25

8257 $17.95

8257-5 $19.00

8259 $19.95

8275 $69.95

8279 $17.50

8279-5 $18.00

8295 $16.50

KEYBOARD CHIPS

AY5-2376 $13.75

AY5-3600 $13.75

BAUD RATE GENERATORS

MC14411 ... $11.00 1.8432 XTAL ...$ 4.95 DISK CONTROLLER

1771B01 $24.95

1791A01(CER) $37.95

EPROMS ^

1702A $ 4.95

2708 $ 6.25

2516 (5V) $18.00

2716 (5V) $13.50

2716 (5 & 12V) $13.50

2758 $19.95

2532 $55.00

2732 $55.00

USRT S23S0 $ 7.95

MISCELLANEOUS OTHER COMPONENTS

N8T20 $ 3.25

N8T26 $ 2.50

N8T97 $ 2.00

N8T98 $ 2.00

1488 $ 1.25

1489 $ 1.25

D3205 $ 3.00

D3242 $14.00

P3404 $ 6.75

TMS5501 $19.00

DM8131 $ 3.00

UARTS

TR1602B $ 4.50

AY5-1013A $ 4.50

CHARACTER GENERATORS

2513 $10.95

UP CASE (5&12V) 2513 $10.95

LWR CASE (5&12V) 2513 $ 9.75

UP CASE (5V) 2513 $10.95

LWR CASE (5V)

6800 PRODUCTS

6802P $18.00

6821P $ 5.25

6840P $18.25

6845P $22.00

6850P. $ 4.80

6860P $11.55

6875P. $ 7.40

V

TELEVIDEO

912C $699.00

920C $799.00

• Typewriter keyboard • Microprocessor controls • Upper/lower case • Adjustable baud rates (75-9600 baud) • Special function keys Second page memory option... $25.00

<

DISKETTES

VER-525-01 Solt sector S27.95

VER-525-10 10 sector $27.95

VER-52S-16 16 sector 527.95

6»" d»i >»■ del der.. bo, oi 10

VER-550-01 Soft sector $39.95

VER-34-1000 Sott sector $33.95

V

VER-34-8000 Soft sector $55.95

dbi sided dbl den bo* of 10 VER-34-4000 Sott sector $57.95

HARD HOLES

FSI-HHD P-cg of 50 lor 8" $15.00

FSI-HDA S" Applicator $ 5.25

FSI-HHM Pkg of 50 tor 5'/." $10.75

FSI-HMA 5'/." Applicator $ 5.00

J

QT MAINFRAMES

Mainframe - Cal Comp Sys 12 stot S-100 mainframe with 20 amp power supply

CCS-2200AT A&T $349.95

QT 8" Disk Mainframe Dual 8" drive cutouts with 6 slot motherboard

QTC-MF*DD6 with 30 amp p.s $625.00

5'/." Disk Mainframes with 18A

QTC-MF»MD12 (12 slot M/B) $500.00

QTC-MF+MD6 (6 slot M/B) $450.00

QTC-MF»MD w/o M/B $400.00

O.T. Mainframe

MF*12 (12 slot M/B) $450.00

MF*18 (18 slot M/B) $500.00

tMF*22 (22 slot M/B) $600.00

DISK DRIVES

OT DISK PACKAGE

Dbl Den Controller A&T. Iwo 8' dbi den drives. GP.M 2 2 cabinet power

supply 4 cables $1395.00

DUAL 8" DRIVES

Dbl Den Duves in Cab.net Only

2 sgl sided (801R) $ 989.00

2 dbl sided (QUME) $1409.00

8" DISK DRIVES

SHUGART lloppy dish drivel igl tided, dbl density.

SHU-801R 5 395.00

Special Sale Price 2 lor $775.00

QME-8DS (851R compatible) 5 599.00

Pkg ol two 5 549.00 ea.

5V," DRIVES MPI-B51 MPI B-51 $ 235.00

Sgl Sided. SglDbi Den Enaci Replacement lor SA-400

MPI-B52 MPI B-52 $ 350.00

Dbl Sided Dbl Den

MPI-B91 MPI 8-91 $ 395.00

Sgl Sided. Dbl Den. 77 Tracks

V

J

rQT MOTHERBOARDS 1

OT Silence Plus

6 Slot 15'." * B- |

... $19.95

QTC-6 Slot K kit

$39.95

QTC-6 Slot AT A81T ....

13 sioi (9 ." < a-. 1

QTC-12 Slot BB Bare board

OTC-12 Slot K kit

$29.95

QTC-12 Slot AT A&T

la sioi ii4v > a. 1

QTC-18 Slot BB Bare board

QTC-18 Slot AT A&T

$ 49.95

QT APPLE CORNER

MEX-16A2 Apple kit $32.00

DISK DRIVE for APPLE

APL-5DC with controller $535.00

APL-5D w/out controller $450.00

8" DRIVES lor APPLE

Controller, two 8" drives, cabinet & cable $1450.00

QT APPLE DISK II Dbl sided, dbl den. two 8" QUME drives with controller, pwr supply, cabinet, cabling, documentation & one box

diskettes $2195.00

QT APPLE DISK III

Same as Above - no controller $1695.00

Al/O - S.S.M. Parallel & serial interlace for your Apple

SSM-AIO K Kit $159.00

SSM-AIO AT A&T $199.00

APPLE CLOCK - OT System

QTC-CCA-AT A&T $125.00

SUPERTALKER - Mtn Hardware

Spe

icogni

MHW-STLK A&T $275.00

Z-80 CARD tor APPLE (MICRO-SOFT)

2-BO CPU card with CP/M lor ydur Apple

MST-Z80 A&T $289.00

MICROMODEM - D.C. Hayes

Auto answer/dial modem card (or Apple or S-100

DCH-MM2 Apple modem $349.95

DCH-MM100 S-100 modem $375.00

^

TEXTOOL

V

ZIP* DIP II SOCKETS

16 PIN ZIP* DIP II $ 5.50

21 PIN ZIP* DIP II $ 7.50

40 PIN ZIP* DIP II $10.25

•ZERO INSERTION PRESSURE

r

BARE BOARDS AVAILABLE ON MANY PRODUCTS

S-100 PRODUCTS

Double Density - Cal Comp Sys

5'/." or 8" disk controller with free CP/M 2.2 CCS-2422A A&T $374.95

SBC-100-SD Systems

2.5 MHz Z80 CPU with serial & parallel I/O ports

SDS-SBC100K Kit $318.00

SDS-SBC100AT A&T $385.00

SBC-200 - SD Systems

4 MHz Z80 CPU with serial & parallel I/O ports

SDS-SBC200K Kit $348.00

SDS-SBC200AT A&T $408.00

CB2 - S.S.M.

2 or 4 MHz switchable Z80 CPU with RAM, ROM & I/O

SSM-CB2K Kit $239.95

SSM-CB2AT A&T $299.95

2810 Z-80 CPU - Cal Comp Sys

2 or 4 MHz Z80A CPU w/serial I/O port

CCS-2810 A&T $275.00

ExpandoRAM I - SD Systems

2.5 MHz RAM board expandable from 16K to 64K

SDS-RAM16K 16K kit $269.95

SDS-RAM16AT 16K A&T $319.95

SDS-RAM32K 32K kit $309.95

SDS-RAM32AT 32K A&T $359.95

SDS-RAM48K 48K kit $349.95

SDS-RAM48AT 48K A&T $399.95

SDS-RAM64K 64K kit $389.95

SDS-RAM64AT 64K A&T $439.95

S-100 Extender - Cal Comp Sys

Puts problem boards within easy reach

kCCS-2520A A&T $ 24.95

ExpandoRAM II - SD Systems

4 MHz RAM board expandable from 16K to 256K

SDS-RAM216K 16K kit $289.95

SDS-RAM216AT 16K A&T $339.95

SDS-RAM232K 32K kit $329.95

SDS-RAM232AT 32K A&T $379.95

SDS-RAM248K 48K kit $369.95

SDS-RAM248AT 48K A&T $419.95

SDS-RAM264K 64K kit $409.95

SDS-RAM264AT 64K A&T $459.95

16K Static RAM - Cal Comp Sys

2 or 4 MHz 16K static RAM - a real memory bargain

CCS-2016B 16K 2 MHz A&T $279.00

CCS-2016BCK 16K 4 MHz A&T $309.00

PB-1 - S.S.M.

2708. 2716 EPROM board with built-in programmer

SSM-PB1K kit $159.95

SSM-PB1AT A&T $239.95

PROM-100 - SD Systems

2708. 2716. 2732, 2758 & 2516 EPROM programmer

SDS-PROM-100K kit $220.00

SDS-PROM-100AT A&T $275.00

I/0-4 - S.S.M.

2 serial I/O ports plus 2 parallel I/O ports

SSM-I04K kit $179.95

SSM-104AT A&T $259.95

SSM-I04BB Bare board $ 35.00

SB1-S.S.M.

15 Hz to 25K Hz music synthesizer for S-100

SSM-SB1K kit $239.95

SSM-SB1AT A&T $299.95

WE ACCEPT M/C VISA & AM EXP

Versatloppy I - SD Systems

Versatile floppy disk controller for 8" or 5%"

SDS-VFIK $265.00

SDS-VFIAT A&T $315.00

Versafloppy II - SD Systems

New double density controller for both 8" & 5V«"

SDS-VF2K kit $385.00

SDS-VF2AT A&T $450.00

VDB-8024 - SD Systems

80 x 24 I/O mapped video board with keyboard I/O

SDS-VDBK kit $406.00

SDS-VDBAT A&T $475.00

VB3 - S.S.M.

80 x 24 x 48 memory mapped with graphics

SSM-VB3-4mhzK kit, 4 MHz $399.95

SSM-VB3-4mhzAT A&T, 4 MHz . . . $464.95 SSM-VB3-4mhzllPG 80 x 48 upgrade. 4 MHz

$ 89.00

VIDEO BOARD -Ithaca Audio

64 x 16 assembled & tested S-100 video board

IIS-VBDAT A&T $99.95

T1 Active Terminator

SSM-T1K kit $ 34.00

SSM-T1AT A&T $ 64.00

VB2 I/O Mapped Video Interface

SSM-VB2K kit $160.00

SSM-VB2AT A&T $210.00

XB1 Extender Board SSM-XB1K kit (with Connector) ... $ 22.00 SSM-XB1AT Assembled & tested .. $ 30.00

Z-80 STARTER KIT - SD Systems

Z-80 computer with RAM. ROM. I/O & keyboard

SDS-Z80K kit $374.00

SDS-Z80AT A&T $454.00

<T

COMPUTER SYSTEMS

J INC.

15620 South Inglcwood Avenue l.avvndale, California 90260 (213) 970-0052

PLACE ORDERS TOLL FREE

1-800-421-5150

(CONTINENTAL U.S. ONLY)

(EXCEPT CALIFORNIA)

Apple is a trademark o I Apple Computer, Inc. CP/M and MP/M are trademarks of Digital Research. TRS-80 is a trademark of Radio Shack.

Circle 312 on inquiry card.

TERMS OF SALE: Cash, checks, money orders, credit cards accepted. Also C.O.D. orders under $100.00. Minimum order $1000. California residents add 6% sales tax. Minimum shipping and handling charge $2.50. Prices subject to change without notice. International sales in American dollars only.

WE'RE GIV

We're not selling it. The JADE Catalog is the best, and the best things in life are free. We will send you our new 1981 edition describing over 4000 microcomputer parts, components, boards, systems, accessories,

S-100 Boards

64K RAM Board - Cal Comp Sys

4 MHz, bank selectable, IEEE standard MEM-64565A A & T $449.95

Memory Bank - Jade

4 MHz, IEEE S-100, bank selectable, 8 or IB bit

MEM-99730K Kit, no RAM $219.95

MEM-16730K 16K kit $249.95

MEM-16730A 16K A & T $299.95

MEM-32731K 32K kit $289.95

MEM-32731A 32K A & T $339.95

MEM-48732K 48K kit $324.95

MEM-48732A 48K A &T $374.95

MEM-64733K 64K kit $359.95

MEM-64733A 64K A & T $409.95

MEM-99730B Bare board $55.00

ExpandoRAM II - SD Systems

4 MHz RAM board expandable from 16K to 256K

MEM-16630K 16K kit $289.95

MEM-16630A 16K Jade A & T $339.95

MEM-32631K 32K kit $329.95

MEM-32631A 32K Jade A &T $379.95

MEM-48632K 48K kit $369.95

MEM-48631A 48K Jade A & T $419.95

MEM-64633K 64K kit $409.95

MEM-64633A 64KJade A & T $459.95

32K STATIC RAM - Jade

2 or 4 MHz expandable static RAM board uses 2114L's

MEM-16151K 16K 4 MHz kit $169.95

MEM-16151A 16K 4 MHz A & T ... $224.95

MEM-32151K 32K 4 MHz kit $299.95

MEM-32151A 32K 4 MHz A & T ... $349.95

16K STATIC RAM - Cal Comp Sys

2 or 4 MHz 16K static RAM - a real memory bargain MEM-16160A 16K 2 MHz A & T ... $279.00 MEM-16162A 16K 4 MHz A & T ... $309.00 MEM-16160B Bare board $29.95

THE BIG Z* - Jade

2 or 4 MHz switchable Z-80* CPU with serial I/O

CPU-30201K Kit $145.00

CPU-30201A A &T $199.00

CPU-30200B Bare board $35.00

SBC-100 - SD Systems

2.5 MHz Z-80* CPU with serial & parallel I/O ports

CPC-30100K Kit $299.95

CPC-30100A Jade A &T $369.95

SBC-200 - SD Systems

4 MHz Z-80* CPU with serial & parallel I/O ports

CPC-30200K Kit $339.95

CPC-30200A Jade A & T $399.95

CB2 - S.S.M.

2 or 4 MHz switchable Z 80* CPU with RAM, ROM, & I/O

CPU-30300K Kit $239.95

CPC-30300A A & T $299.95

2810 Z-80* CPU - Cal Comp Sys

2/4 MHz Z-80 A* CPU w/serial I/O port CPU-30400A A & T $275.00

DOUBLE-D-Jade

Double density controller with the inside track

IOD-1200K Kit $299.95

IOD-1200A 8"A&T $389.95

IOD-1205A 5'/," A&T $389.95

IOD-1200B Bare board $65.00

DOUBLE DENSITY - Cal Comp Sys

5V," or 8" disk controller with free CP/M 2.2 IOD-1300A A & T $374.95

VERSAFLOPPY II - SD Systems

New double density controller for both 8" & 5'A"

IOD-1160K Kit $379.95

IOD-1160A Jade A &T $439.95

S.P.I.C. - Jade

Our new I/O card with 2 SIOs, 4 CTC's, and 1 PIO IOI-1045K 2 CTC's, 1 SIO, 1 PIO .. $199.00

IOI-1045A A & T $259.00

IOI-1046K 4 CTC's, 2 SIO's, 1 PIO $259.00

IOI-1046A A & T $319.00

IOI-1045B Bare board w/ manual . .. $59.95 IOI-1045D Manual only $20.00

1/0-4 - S.S.M.

2 serial I/O ports plus 2 parallel I/O ports

IOI-1010K Kit $179.95

IOI-1010A A&T $259.95

IOI-1010B Bare board $35.00

100K DAY CLOCK - Mtn Hardware

Crystal controlled S-100 clock with NiCad backup IOK-1400A A&T $329.95

SB1 - S.S.M.

15 Hz to 25K Hz music synthesizer for S-100

IOS-1005K Kit $239.95

IOS-1005A A&T $299.95

TB-4 - Mullen

Extremely versatile extender board with logic probe

TSX-180K Kit $55.00

TSX-180A A&T $75.00

S-100 EXTENDER - Cal Comp Sys

Puts problem boards within easy reach TSX-160A A&T $24.95

VIDEO BOARD - Jade

64 x 16 assembled & tested S-100 uideo board

IOV-1050B Bare board $25.00

IOV-1050K Kit $99.95

IOV-1050A A&T sale price $139.95

VDB-8024 - SD Systems

80 x 24 I/O mapped uideo board with keyboard I/O

IOV-1020K Kit $399.95

IOV-1020A Jade A&T $459.95

VB3 - S.S.M.

80 x 24 or 80 x 48 memory mapped with graphics

IOV-1095K Kit, 4 MHz $399.95

IOV-1095A A&T, 4 MHz $464.95

IOV-1096K 80 x 48 upgrade, 4 MHz . $89.00

PB-1 - S.S.M.

2708, 2716 EPROM board with built-in programmer

MEM-99510K Kit $159.95

MEM-99510A A&T $239.95

PROM-100 - SD Systems

2708, 27i6, 2732, 2758, & 2516 EPROM programmer

MEM-99520K Kit $219.95

MEM-99520A Jade A & T $269.95

Single Board Computers

AIM-65 - Rockwell

6502 computer with printer, display, & keyboard

CPK-50165 IK AIM $374.95

CPK-50465 4K AIM $449.95

SFK-74600008E 8K BASIC ROM ...$99.95 SFK-64600004E 4K assembler ROM $84.95

PSX-030A Power supply $64.95

ENX-000002 Enclosure $49.95

4K AIM, 8K BASIC, power supply, & enclosure Special package price $625.00

Z-80* STARTER KIT - SD Systems

Z-80* computer with RAM, ROM, I/O, & keyboard

CPS-30010K Kit $369.95

CPS-30010A Jade A&T $459.95

Motherboards

ISO-BUS-Jade

Silent, simple, and on sale - a better motherboard 6 Slot (5'/." x 8%")

MBS-061B Bare board $19.95

MBS-061K Kit $39.95

MBS-061A A&T $49.95

12 Slot (W x 8yB")

MBS-121B Bare board $29.95

MBS-121K Kit $69.95

MBS-121A A&T $89.95

18 Slot (14'//' x 8s/s")

MBS-181B Bare board $49.95

MBS-181K Kit $99.95

MBS-181A A&T $139.95

Mainframes

MAINFRAME - Cal Comp Sys

12 slot S-100 mainframe with 20 amp power supply

ENC-112105 Kit $309.95

ENC-112106 A&T $349.95

DISK MAINFRAME - NNC

Dual 8" driue cutouts with 8 slot motherboard ENS-112320 with 30 amp p.s $699.95

Video Monitors

9" B & W MONITOR - A.P.F.

High quality, high resolution uideo monitor VDM-750900 9" monitor $149.95

13" COLOR MONITOR - Zenith

The hi res color you'ue been promising yourself VDC-201301 $449.00

12" GREEN SCREEN - NEC

20MHz, P31 phosphor uideo monitor with audio VDM-651200 12" monitor $249.95

SUP'R'MOD II - M & R Assoc

Color or B & W TV interface recommended for Apple IOR-5050A A&T $29.95

ING IT AWAY

peripherals, and software. All you have to do is ask for it. Just circle our inquiry number on the reader service card in the rear of this magazine and we will send you the best. It's free and it's easy.

Accessories for Apple

16K MEMORY UPGRADE

Add 16K of RAM to your TRS-80, Apple, or Exidy

MEX-16100K TRS-80 kit $39.95

MEX-16101K Apple kit $39.95

MEX-16102K Exidy kit $39.95

DISK DRIVE for APPLE

5'//' disk drive with controller for your Apple

MSM-12310C with controller $475.00

MSM-123101 w/out controller $375.00

8" DRIVES for APPLE

Complete kit with controller, DOS, and two 8" drives Special package price $1475.00

AIO - S.S.M.

Parallel & serial interface for your Apple

IOI-2050K Kit $159.00

IOI-2050A A & T $199.00

PRINTER INTERFACE - Cal Comp

Sys

Centronics type I/Ocard w/ firmware IOI-2041A A & T $99.95

APPLE CLOCK - Cal Comp Sys

Real time clock w/battery back-up IOK-2030A A & T $119.95

SUPERTALKER - Mtn Hardware

Speech recognition/synthesizer w/speaker & mike IOS-2015A A&T $275.00

Z-80* CARD for APPLE

Z-80* CPU card with CP/Mfor your Apple CPX-30800A A&T $279.95

MICROMODEM - D.C. Hayes

Auto answer/dial modem card for Apple or S-100

IOM-2010A Apple modem $349.95

IOM-1100A S-100 modem $375.00

Micronet Modem - Micromate

Direct connect modem with extra features IOM-2020A Best Apple modem $275.00

8" Disk Drive Sale Printers

EPROM ERASERS

Spectronics hi intensity industrial eraser

XME-3100 Without timer $69.95

XME-3101 With timer $94.50

L.S. Engineering UV eraser for up to 48 EPROMs XME-3200 A&T $39.95

JADE's new dual disk sub-assemblies include: Handsome metal cabinet with proportionally balanced air flow system, rugged dual drive power supply, cooling fan, cable kit, lighted power switch, approved fuse assembly, line cord, NeverMar rubber feet, and all necessary hardware to mount 2-8" disk drives - it's all American made, guaranteed for six monthes, and it's in stock! Dual 8" Sub-Assembly Cabinet

END-000421 Cabinet kit $225.00

END-000420 Bare cabinet $59.95

Single sided, double density disk drive sub-system END-000423 Kit w/2 8" drives .... $995.00 END-000424 A & T w/2 8" drives $1195.00

Doublesided,double density disk drive sub-system END-000426 kit w/2 8" drives .... $1495.00 END-000427 A & Tw/2 8" drives $1695.00

8" DISK DRIVES

Highly reliable double density floppy disk drives Shugart 801R single sided, double density

MSF-10801R SA-801R $425.00

Special Sale Price 2 for $790.00

Siemens FDDL00-8D2 single sided, double density

MSF-201120 6 mo warranty $395.00

Special sale price 2 for $750.00

Qume Datatrak 8 double sided, double density MSF-750080 SA-851R compatible .. $625.00 Special sale price 2 for $1198.00

JADE DISK PACKAGE

Double-D controller kit, two 8" double density drives

CP/M 2.2, cabinet, power supply, & cables

Special package price $1395.00

DISKETTES - Jade

Bargain prices on magnificent magnetic media 5lA" single sided, single density, box of 10

MMD-5110103 Soft sector $27.95

MMD-5111003 10 sector $27.95

MMD-5111603 16 sector $27.95

5'/i" doublesided, double density, box of 10

MMD-5220103 Soft sector $39.95

8" single sided, single density, box of 10

MMD-8110103 Soft sector $33.95

8" single sided, double density, box of 10

MMD-8120103 Soft sector $39.95

8" double sided, double density, box of 10 MMD-8220103 Soft sector $57.95

NOVATION CAT

300 baud, auto answer/originate acoustic modem IOM-5200A Special sale price $139.00

D-CAT 300 baud, direct connect modem IOM-5201A Special sale price $179.00

* Z-80, Z-80 A, and the let terZ are recognized trademarks ofZilog, Inc. *CP/M is a registered trademark or Digital Research Corp. *CBASIC is a trademark of Compiler Systems, Inc.

Circle 313 on inquiry card.

SPINWRITER - NEC

65 cps, bi-directional, letter quality with tractor PRD-55510 with 16K buffer $2595.00

CENTRONICS 737-1

9 x N dot matrix, letter quality, proportional spacing

PRM-15737 Parallel $795.00

With interface for Apple $895.00

MX-80 - Epson

132 column, 9x9 dot matrix, multiple fonts

PRM-27080 Save $100.00 $545.00

Interface for Apple $110.00

MICROPROCESSORS

Z-80 10.95

Z-80A 12.95

6502 11.50

6800 11.95

6802 17.95

6809 39.95

8035 24.00

8080A 6.59

8085 15.95

8748 59.95

Z-80 SUPPORT

3881 PIO 9.50

3881-4 P [0-4 MHz . 14.50

3882 CTC 9.50

3882-4 CICAMHz 14.95

3883 SIO 29.50

3884 670 49.50

6800 SUPPORT

6821P 5.95

6828P 11.95

6834P 22.50

6840P 18.75

6800 P 4.80

6852P 5.79

6875L 7.40

68488P 25.00

BAUD RATE GENERATORS

MC14411 10.00

1.843 MHz xtal 4.95

UARTS

AY5-1013A 5.25

AY3-1014A 8.25

TR1602B 5.25

TMS6011 5.95

IM6402 9.00

PROMS

2708 450ns 8^5

10 for $59.00

2716 12.5u 12.95

2716 Sv 12.95

10 for $99.00

2532 Sv 39.95

2732 Su 39.95

2758 Sv 19.95

RAMS

21L02 2 MHz 1.25

21L02A 4 MHz 1.50

2114L 2 MHz 3.75

2114LA 4 MHz 3.95

2147 70ns 39.95

4116 4.95

4164 64K xl 175.00

5257 2 MHz 6.75

5257A 4 MHz 7.25

MK4118 18.95

SUPPORT

DEVICES

8212 4.95

8214 4.65

8216 2.95

8224 3.25

8224-4 10.95

8226 3.85

8228 4.95

8238 4.95

8243 8.00

8250 14.95

8251 650

8253 13.95

8255 6.50

8257 19.95

8259 17.95

8275 49.95

8279 15.95

PLACE ORDERS TOLL FREE

Continental U.S. Inside California 800-421-5500 800-262-1710

For Technical Inquiries or Customer Service call

213-973-7707

Computer Products

4901 W. Rosecrans, Hawthorne, Ca 90250

TERMS OF SALE: Cash, chocks, credit cards, or Purchase Orders from qualified firms and institutions. Minimum order $15.00. California residents add 6% tax. Minimum shipping and handling charge $2.50 Pricing and availability subject to change without notice.

SN74O0N

.25

7401

SN74156N

.79

SN7401N

.20

SN74157N

.63

SN7402N

.25

SN7472N

.29

SN74160N

.89

SN7403N

.25

SN7473N

.35

SN74161N

.as

SN7404N

.25

SN7474N

.35

SN74162N

.89

SN7405N

.29

SN7475N

.49

SN74163N

.89

SN7406N

.35

SN7476N

.35

SN74164N

-83

SN7407N

.35

SN7479N

5.00

SN74165N

.89

SN7408N

.29

SN7480N

.50

SN74166N

1.25

SN7409N

.29

SN7482N

.99

SN74167N

2.73

SN7410N

.25

SN74B3N

.69

SN74170N

1.35

SN7411N

.29

SN7485N

.89

SN74172N

4.95

SN7412N

.35

SN7486N

.35

SN74173N

1.33

SN7413N

.40

SN74B9N

1.75

SN74174N

.39

SN7414N

.69

SN7490N

.49

SN7417SN

.89

SN7416N

.29

SN7491N

.59

SP074176N

.73

SN7417N

.29

SN7492N

.45

SN74177N

.73

SN7420N

.25

SN7493N

.45

SN74179N

1.49

SN7421N

.29

SN7494N

.69

SN74180N

.79

SN7422N

.45

5N7495N

.69

SN74181N

2.25

SN7423N

.29

SN7496N

.69

SN74182N

.79

SN7425N

.29

SN7497N

3.00

SN74184N

2.49

Sro7426N

.29

SN7410QN

1.49

SN74185N

2.49

SN7427N

.25

SN741Q7N

.35

SN74190N

1.25

SN7429N

.39

SN74109N

.39

SN74191N

1.25

SN7430N

.25

5N74116N

1.95

SN74192N

.89

SN7432N

.29

SN74121N

.39

SN74193N

.89

SN7437N

.25

SN74122N

.55

SN74194N

.89

SN743BN

.40

SN74123N

.59

SN74195N

.69

SN7439N

.25

SN74125N

.49

SN74196N

-89

SN7440N

.20

SN74126N

.49

SN74197N

.89

SN7441N

.89

SN74132N

.75

SN74198N

1.49

SN7442N

.59

SN74136N

.75

SN74199N

1.49

SN7443N

1.10

SN74141N

.99

SN74221N

1.25

SN7444N

1.10

SN74142N

3.25

SN7425LN

.99

SN7445N

.89

SN74143N

3.49

SN74276N

1.95

SN7446N

.79

SN74144N

3.49

SN74279N

.79

SN7447N

.69

SN74145N

.79

SN74283N

1.49

SN7448N

.79

SN74147N

1.95

SN742B4N

3.95

SN7450N

.20

SN7414BN

1.29

SN74285N

3.95

SN7451N

20

SN741S0N

1.25

SN74365N

.69

SN74S3N

.20

SN74151N

.69

SN74366N

.69

SN74S4N

.20

SN74152N

.69

SN74367N

.69

SN7459A

-25

SN74153N

.79

SN74368N

.69

SN7460N

.20

SN74154N

1.25

SN74390N

1.49

SN7470N

.29

SN74155N

.79

SN74393N

1.49

74LS0O

.29

74LS

74L5192

1.15

74L5193

1.15

74LS02

.29

74LS92

.75

74LS194

1.15

74LS03

.29

74LS93

.75

74LS195

74LS04

.35

74LS95

.99

74LS197

1.19

74LS05

.35

74L596

1.15

74LS221

1.19

74LS08

.29

74LS1Q7

.45

74LS240

1.95

74LS09

.35

74LS109

.45

74LS241

74LS10

.29

74LS112

.45

74LS242

74LS11

.75

74LS113

.49

74L5243

74LS12

,31

74L5114

.49

74LS244

1.95

74LS13

74LS122

.89

74LS245

74LS14

.99

74LS123

1.2S

74LS247

1.19

74LS15

.35

74LS125

.59

74LS248

1.19

74LS20

.29

74L5126

.55

74LS249

1.19

74LS21

.35

74LS132

.99

74LS251

1.49

74LS22

.35

74LS133

.as

74LS253

.99

74LS26

.35

74LS136

.49

74LS257

.89

74LS27

.35

74LS13B

.89

74L5258

74L52S

.35

74LS139

.89

74LS260

74L530

.29

74LS151

.89

74L526E

.69

74LS32

.35

74L5153

.89

74LS273

1.95

74LS33

.59

74LS1S4

1.75

74LS279

.75

74LS37

.45

74LS155

1.19

74LS283

1.09

74LS3B

.49

74LS156

1.19

74LS290

74LS4Q

.35

74LS157

.89

74LS293

74LS42

.89

74LS158

.99

74L5298

1.25

74LS47

.89

74LS16Q

1.15

74LS352

74LS48

1.15

74L5161

1.15

74L5353

1.29

74LS49

1.15

74L5162

1.15

74LS365

.75

74LSS1

.29

74L5163

1.15

74LS366

.75

74LSS4

.29

74LS164

1.25

74LS367

.75

74LS55

.29

74L5165

1.25

74L5368

74LS73

.45

74LS168

1.19

74LS373

74L574

.45

74LS169

1.19

74L5374

74LS7S

■59

74LS170

2.49

74LS375

.89

74L576

.45

74LS173

1.39

74L5386

fiS

74LS78

.49

74LS174

.99

74LS393

2.49

74LS83

.89

74LS175

.99

74L5399

2.49

74LS85

1.25

74LS1B1

2.95

74LS670

74L58&

.45

74LSL90

1.25

B1LS95

74L590

.59

74LS191

1.25

S1L597

1.95

74500 74S02 74S03 74504 74S05 74508 74S09 74S1D 74S11 74515 74520 74S22 74530 74S32 74S40 74S51 74S64 74565 74S74 74586 745112 745113 745114

74S

ITED A'

745133

74S134 74S135 745136 74S138

745139 745140 74S151 745153 745157 74S15B 745174 745175 74S18B 745194 745195 745196 74S24G 745241 745242 745243 AILABILITV

3.95 2.95 2.95 3.25

74.5244

74S251

74S253

745257

745258

745260

745280

74S2B7*

745288*

745373

745374

745387'

745471*

745472*

74S473*

745474*

74S47S*

745570*

745571* 7

745572* 19

745573* 19

745940 3

745941 3 ESE PROMS

2.95 4.95 4.95

3.49 3.49 5.95 19.95 19.95 19.95 21.95 21.95

CA3013H 2,15

CA3023H 3.25

CA3039H 1.35

CA304GN 1.30

CA3059N 3.25

CA3060N 3.25

CA3Q80H 1.25

CA-LINEAR

CA30SIN 2.00

CA3082N 2.00

CAJC83N 1.60

CA30S6N .85

3.95

CA3089N CA3096N

CA3130H 1.39

CA3140H 1.25

CA3160H 1.25

CA3401N .59

CA360QN 3.50

CD4000 CD4001 CD4002 CD4006 CD4007 CD40Q9 CD4010 CD4011 CD4012 CD4013 CD4014 CD4015 CD4016 CD4017 CD4018 CD4019 CD4D20 CD4Q21 CD4022 CD4023 CD4024 CD4025 CD4026 CD4027 CD4028 CD4029 CD403O CD4035 CD4O40

V CD4W

CD-CMOS

CD4041 CD4042 CD4043 CD4044 CD4046 CD4047 CD404B CD4049 CD4050 CD4051 CD4052 CD4053 CD4056 CD4059 CD4060 CD4065 CD4068 CD4069 CD4070 CD4071 CD4072 CD4073 CD4075 CD4076 CD4031

CD4082

CD4093

CD409B

CD4506

CD4507

CD4508

CO4510

CD4511

CD4514

CD4515

CD4516

CD451B

CD4519

CD4520

CD4526

CD452S

CD4529

CD4543

CD4562

CD4566

CD4583

CD4723

CD4724

MC 14409

MC14410

MC14411

MC14412

MC14419

MC14433

2.79 11.95 2.79

14.95 14.95 14.95 11.95

LITRONIX DISPLAY SALE

DL-4500 DL-4507 DL-4520A DL-4120A

ECTtm ARRAYS FOR CLOCKS

«**,—

,;■!:»

POl*n„Y

_«

=

'»«"

C?OMWAnDS

mm

fW

1YP

VAX

'-"'""■

;;;■!■";!!:;:

.

etfln

s£

s

"

"

»

■

2.49

DtStSwKw

«_

'

"

4.S5 4.95 2.49

DMUMbM

10

tc™«w

is

■i

3i

..,,

4.9S

multi man reflector arrays

0L1MXSMI

.m

CC.MM

?=., ?D.«.TDC Kg-.l

;■■

ii

n

1.1

n

30

1.49

OkO«MIW*Ml

K

Cfl HW(

»5^ JD.g.l

M

::"!

it

»

Dv4tcam«u

U

ce mpi

aw tDwtO* H.*l

s

«

HI

1.7

70

30

Z.49

DLOSOQIHMI

n

ttuw

?S^6

,.ll.l

Hum

I

5

ii)

1>

30

30

Z.95

!U 1M.1 lllrtl

',:>

C B UM

;;,.; I.

Mill

«,'i

I

',

10

11

70

30

Z.93

DL-»30(MI

■

a* <;<■>■

;:*j )

,.(1!

„,

■■'j

10

.0 , 3.

'»

w

3.95

DISCRETE LEDS

XC556R .200" red

XC556G .200" greer

XC556V ,200" yello

XC556C .200" clear

XC22R .200" red XC22G

syn

4/11 4/11

4/11

5/U 4/tl

XC22V .200" yellow 4/11 MV10B .170" red 4/S1

MV50 .085" red

XC209R .125" red

XC209G .125" green

XC209Y .125" yellow

XC526R .IBS" red

XC526G .185" green

XC526V .185" yellow

XC526C .185" clear

6/(1 5/S1

4/S1

4/J1

5/11 4/J1

4/$l

4/J|

XC111R .190" red 5/S1

XC111G .190" green 4/J1

XC111V .190" yellow 4/tl

XC1UC .190" clear 4/J1

efjfc,

RL-2 . .S.39ea.or3/S1.00

C.A.

Type

MAN 1 MAN 2 MAN 3 MAN 52 MAN S4 MAN 71 MAN 72 MAN 74 MAN 82 MAN 84 MAN 3620 MAN 3630 MAN 3640 MAN 4610 MAN 6610 MAN 6630 MAN 6640 MAN 6650 MAN 6660 MAN 6710 MAN 6750 MAN 6780 DLO304 DLO307 DLGSOO

Con

ion Anod

Polarity >

C.A.-red 5x7 D.M. —red C.C.-red C.A.—green C.C.—green C.A.—red C.A.—red C.C.-red C.A.—yellow C.C.—yellow C.A.—orange C.A.—orange ± 1 . C.C.—orange C.A.—orange C.A.—orange-DD . C.A.-orange ± 1 C.C.-orange—DD . C.C.—orange ± 1 C. A.—oran9e C.A. —red —DD C.C.—red * 1 C.C.-red C.C.—orange C.A.—orange CX.—green

DISPLAY LEDS "-c™

n Cathode

Price 2.95 4.95

Type

DLG507

DL704

DL707

DL728

DL741

DL746

DL747

DL750

DL0847

DLOB50

DL33B

FND358

F N D 359

FND503

FND507

HDSP-3401

HDSP-3403

50B2-7751

5082-7760

5082-7300

5082-7302

5082-7304

4N28

LIT-1

MOC3010

Polarity

C.A.-green .1

C.C.-red

C.A.-red

C.C.—red -i

C.A.-red .1

C.A.-red t 1 .1

C.A.-red .1

C.C.-red .1

C.A.-orange .;

C.C.-orange .!

C.C.-red

CX. ± 1

CX. .:

CX. (FND5O0) .!

C.A. (FNOS10) .!

C.A.-red .1

C.C.-red

C.A..R.H.D.—red .<

C.C.R.H.D.—red ..

4x7 591, dig. RHD .i

4x7 59I. dig. LHO J

Overnge.char.ftl) .1

PHoto XslstorOpto

Photo Xsistor Opto

Optlcaily isol.Trlac I

22.00

22.00 19.95

POTENTIOMETERS

$2.95 each

2 Watt & 70°C

10%

■g 7/8" Slotted Sho

ft

rf Linear 1 aper

^ Meets Mil-R-94

RV4NAY SD- 102A

HV4NAY SD • 502A

5K

RV4NAY SD ■ 103A

10K

RV4NAY SD - 2S3A

25K

RV4NAY SD - 503A

SOK

RV4NAY SD - 104A

100K

RV4NAY SD - 105A

lMeg

LOW PROFILE (TIN) SOCKETS

ii if nr

SOLDERTAIL (GOLD) STANDARD

$1.35 each

3/4 Watt Ii* 7Q°C

B30P- 50ohrr B30P-100onrr _830P-500ohrr B30P-1K B30P-2K

830P- 5K B30P-10K 83OP-20K 830P-50K

Part No. B30P-100K 830P-200K 830P-5O0K 830P-lMeg

M9

h if nr

SOLDERTAIL STANDARD (TIN}

14 c

I ST

16 Dii15 Din ST 24 pin ST 28 Pin ST 36 pin ST 40 Pin ST

WIRE WRAP SOCKETS (GOLD) LEVEL #3

8 pin WW 10 pin WW 14 pin WW 16 pin WW 18 Pin ww 20pin WW 22 pin ww 24 pin ww 28 pin WW 36 pin WW 40 pin WW

1/4 WATT RESISTOR ASSORTMENTS -5%

ASST

1

Sea.

10 Ohrr 27 Ohrr

12 Ohrr 33 Ohrr

15 Ohfl 39 Ohn

18 Ohrr 47 Ohrr

22 Ohm 56 Ohm

50 pes.

$1.95

ASST

2

5ea.

68 Ohrr

180 Ohm

82 Onm

220 Ohrr

1M Orin

270 Ohn

120 Ohm 150 Ohm 330 Ohm 390 Ohm

50pcs.

$1.95

ASST

3

5ea.

470Onrr 1.2K

560 Onrr

1.5K

580 onn 1.8K

820 Ohm

2.2K

IK 2.JK

50pcs.

$1.95

ASST

4

5ea.

3.3K S.2K

3.9K 10K

4.7K 12K

5.6K 1SK

6.8K 18K

50 pes.

$1.95

ASST

5

5ea.

22K

56K

27K 68K

33K 82K

39K

100K

47K 120K

50 pes.

$1.95

ASST

6

5ea.

J50K 390K

180K 470K

220K 560K

270K 680K

330K 820K

50 pes.

$1.95

ASST

7

Sea.

1M 2.7M

1.2M 3.3M

1.5M 3.9M

1.8M 4.7M

2.2M 5.6M

50pcs.

$1.95

ASST. 8 R

Includes Resistor Assts. 1-7 (350 pes.)

$10.95 ea.

$10.00 Min. Order - U.S. Funds Only Calif. Residents Add 6% Sales Tax Postage-Add 5%plusS1 Insurance

J kill'. — i^^»iM:i[g

Spec Sheets - 25tf

Send 41rf Postage for your

FREE 1981 JAMECO CATALOG

PHONE

ORDERS

WELCOME

(415)592-8097

MAIL ORDER ELECTRONICS - WORLDWIDE

1355 SHOREWAV ROAD, BELMONT, CA 94002

PRICES SUBJECT TO CHANGE

Part No.

7045 IP I

7045EV/KU*

7106CPL

7106EV/KU*

7107CPL

7107EV/KU*

7U6CPL

7117CPL

7201 ID R

7205IPG

7Z05EV/Kit*

7206CJPE

7205CEV/Kit*

7207AIPD

7207AEV/KH*

7208IPI

7209IPA

7215IPG

7215EV/KU*

7216AIJI

721ECIJI

7216DIPI

7217IJI

721SC1JI

7224 IP L

7226AIJL

7226AEV/KU*

7240IJE

7242IJA

7250IJE

7ZS0UE

7555IPA

7556IPD

7611BCPA

7612BCPA

7621BCPA

7631CCPE

7641CCPD

7642CCPD

7660CPA

B069CCQ

B211CPA

B212CPA

Function

CMOS Precision Timer Stopwatch Chip, XTL Wt Digit A/D (LCD Drive) IC, Circuit Board, Display i'/i Digit A/D (LED Drive) IC, Circuit Board, Display 3Vi Digit A/D LCD DIs. HLD. 3'/; Digit A/D LED Dis. HLD. Low Battery Volt Indicator CMOS LED Stopwatch/Timer

Conti

r Chip, XTL lller

Osdiiato

Freq. Counter Chip, XTL Seven Decade Counter

4 Func. CMOS Stopwatch CKT

4 Func. Stopwatch Chip, XTL B-Diglt Univ. CounterC.A. B-Diglt FreQ. Counter C.A. 8-Dlglt Freq. Counter C.C. 4-Dlgit LED UP/Down Counter B-Diglt Univ. LED Drive LCD 4Vi Digit Up Counter DRI B-Diglt Univ. Counter

5 Function Counter Chip, XTL CMOS Bin Prog.Tlmer/Counte CMOS DIvlde-by-256 RC Timer CMOS BCD Prog. Timer/Count CMOS BCD Prog. Timer/Count CMOS 555 Timer (8 pin) CMOS 556 Timer (14 pin) CMOS Op Amp Compar CMOS Op Amp Ext. Cn CMOS Dual Op Amp Cc CMOS Trl Op Amp Con CMOS Quad Op Amp C CMOS Quad Op Amp C Voltage Converter 50ppm Band-GAP Volt Ref/lndlcator Volt Ref/lndlcator

INTERSIL'S EVALUATION KITS

Price

14.95

22.95 16.95 34.95 15.95 28.95 IS.95 17.95 2.25 12.95 19.95 5.15 9.95 6.50

13.95 19.95 32-00 26.95 21.95 12.95 10.95 11.25 31.95 74.95

5M

1.45 2.20

• 2.25

5MV 2.95

5MV 3.95

10MV 5.35

10MV 7.50

10MV 7.50

2.95

It Ref. Diode 2.50

2.50

2.50

74C00 74C02 74C04 74C08 74C10 74C14 74C2Q 74C30 74C42 74C48 74C73 74C74 74CBS 74CS6 74CE9 74C90 74C93 74C95

.39 .39

74C

74C195 74C221

.39

74C240

.39

74C106

.75

74C244

.39

74C107

1.B9

74C373

.75

74C151

2.95

74C374

.39

74C154

3.95

74CM1

.39

74C157

2.25

74C903

1.39

74C160

1.69

74C911

1.95

74C161

1.60

74C912

.79

74C162

1.49

74C915

.79

74C163

1.69

74C917

1.95

74C164

1.59

74C922

.99

74C173

1.39

74C923

6.95

74C174

1.39

74C925

1.29

74C175

1.39

74C926

1.29

74C192

1.69

B0C95

1.59

74C193

1.69

80C97

LH0OO2CN

LM10CLH

LMUCLH

LH0070-OH

TL07JCP

TL072CP

TL074CN

LHQ082CD

TL082CP

TL084CN

LH0094CD

LM300H

LM301CN

LM302H

LM304H

LM30SH

LM307CN

LM308CN

LM309H

LM309K

LM310CN

LM311H

LM312H

LM317MP

LM317T

LM317K

LM318CN

LM319N

LM320K-5

LM320K-12

LM320K-15

LM320T-5

LM320T-12

LM320T-15

LM323K-5

LM324N

LM329D2

LM331N

LM334Z

LM33SZ

LM3362

LM337T

LM337MP

LM338K

LM339N

LM340K-5

LM340K-12

LM340K-15

LINEAR

LM340T-5

LM340T-12

LM340T-15

LM341P-5

LM341P-12

LM341P-15

LM342P-5

LM342P-12

LM342P-15

LM34BN

LM3S0K

LF351N

LF353N

LF355N

LF356N

LM358N

LM359N

LM370N

LM373N

LM377N

LM3B0N

LM3B1N

LM3B2N

LM384N

LM3B6N-3

LM3B7N

LM389N

LM392N

LF39BN

LM399H

TL494CN

TL496CP

NE510A

NE529A

NE531H

NE536H

NES40H

NES44N

NE550A

NE555V

LM556N

NE564N

LM565N

LM566CN

LM567V

CAPACITOR CORNER

5 0 VOLT CERAMIC DISC CAPACITORS

NE570N 4.S

LM702H .1

LM703CN .1

LM709N .;

LM710N .:

LM7IIN .;

LM723N .1

LM733N 1.1

LM739N 1..

LM741CN .; MC1741SCG 3.1 LM747N

LM74BN .!

LM1014N 2.:

LM1310N l.i

LM1458CN .:

LM14B8N I.;

LM14B9N 1.;

LM1496N U

LM1556V 1.1

LM1B0ON 2.!

LM1877N-9 3.1

LM1889N 3.1

LM1896N 1.

LM2002T l.i

LM2877P 2.1

LM2B7BP 2.1

LM2B96P-1 2.;

LM3189N 2.!

LM3900N ,i

LM3905CN 1.;

LM3909N 1.

LM3914N 3.

LM3915N 3.

LM3916N 3.

RC4136N 1.;

RC4151NB 3.

RC4194TK 5.

RC4195TK 5.

KB442B 4.

KB4429 5.'

LM45O0A 3.i

ICLB03SB 4.!

LM13060N I.;

LM13600N 1.'

7513BN 1.'

75450N .1 7545 l'CIM

22P1 47PI 100 pf 220 pf

470 pi

1-9 10-99 100*

1-9 10-99 100

.OOlMF

.004 Iti F

.OlMF

.02:!|i f

,017uF

.IMF 100 VOLT MYLAR FILM CAPACITORS QOlmf .12 .10 .07 I .022mf .13 .11

0022mf .12 .10 .07 .Q47mf .21 .17

.0047m1

,01rr

.12 .10

.07

.22rr

.33

+20% DIPPED TANTALUMS (Solid) CAPACITORS

.1/35V • 15/35V

.22/35V .33/35V .47/35V .68/35V 1.0/35V

1.S/3SV

2.2 /35 V 3.3/2SV 4.7/25V 6.8/25V 15/2SV 22/6V

MINI. ALUMINUM ELECTROLYTIC CAP AC ITORS

.47/5QV

1.0/50V

3.3/50V

4.7/25V

10/2SV

10/S0V

22/25V

22/50V

47/35V

47/5 0v

100/25 v

100/S0V

220/25V

220/SOV

470/25V

1000/16V

2200/16V

.28 .24 .22

-47/2SV

.47/50V

1.0/16V

IjORSV

1.0/50V

4.7/16V

■i.,", 2S \ '

4.7/50 V

10/16V

10/25 V

10/50V

47/50V

100/16V

1O0/25V

100/50V

220/16V

470/25V

.35 .31 .27

368 BYTE February 1981

Circle 314 on inquiry card.

/H

SSL.**Clock Modules

-j—

12VDC

AUTOMOTIVE/

INSTRUMENT

CLOCK

APPLICATIONS:

• In-dash autodock;

• Aft

HV c

to/

:raft-n

• 12VDCoper. Instru.

• Portable/battery powered insuumnis.

Features;Bright 0.3"green display- Internal crystal timebase. ± 0.5 sec ./day accur.AuiO.display brightnesscontrol logic. Display color filterable to blue, blue-green, green & yellow. Complete-just add switches and lens.

MA1003 Module $16.95

MA1023.7" Low Cost Digital LED Clock Module 8.95

MAI 026 .7" Dig. LED Alarm Clock/Thermometer 18.95

MA5036 ,3"LowCost Digital LED Clock/Timer 6.95

MA1002 .5"LED Display Dig. Clock & Xformer 9.95

2 National Semiconductor

RAM SALE

MM5290N-4 (mk41i6/upd416) . . $4.95 each

16K DYNAMIC RAM (250NS)

(B EACH S39-95) (100 EACH S450.00/lot)

MM5290J-2 IMK4H6/UPD416) . . $6.95 each

16K DYNAMIC RAM (150NS)

(8 EACH S49.95) (100 EACH S550.00/lot)

MM5298J-3A $3.25 each

8K DYNAMIC RAM (LOW HALF OF MM5290J) 200NS (8 EACH S23.95) (100 E AC H $250. OO/lo t)

MM2114-3 $5.95 each

4K STATIC RAM (300NS)

(8 EACH S43.95) (100 EACH S450.00/lot)

MM2114L-3 $6.25 each

4K STATIC RAM (LOW POWER 300NS) (8 EACH S44.95) (100 EACH S475.00/lot)

EPROM Erasing Lamp

• Erases 2708, 2716, T702A, 5203Q, 5204Q, etc.

• Erases up to 4 chips within 20 minutes.

• Maintains constant exposure distance of one inch.

• Special conductive foam liner eliminates static build-up.

• Built-in safety lock to prevent UV exposure.

• Compact - only 7-5/8" x 2-7/8" x 2"

• Complete with holding tray for 4 chips.

UVS-11E $79.95

Jumbo 6-Digit Clock Kit

• Four .630"ht. and two .300"ht. common anode displays

• Uses MM5314 clock chip

• Switches for hours, minutes and hold functions

• Hours easily viewable to 30 feet

• Simulated walnut case

• 115VAC operation

■ 12 or 24 hour operation

• Includes all components, case and wall transformer

► Size: 6?i" x 3-1/8"

i 1ST

JE747 $29.95

6-Digit Clock Kit

• Bright .300 hi. comm. call

• Uses MM5314 clock chip •Swiiches for hours, mrnun

and hold modes

• Hrs. easily viewable lo 20 f •Simulated walnui case

JE701 $19.95

Regulated PowerSupply

Uses LM309K. Heat sink provided. PC board con- ■— struction. Provides a solid 1 amp @ 5 volts. Can supply up to ±5V. t9V and ±12V with JE205 Adapter. Includes components, hardware and instructions. Size: 3H" x 5" x 2"H

JE200 $14.95

ADAPTER BOARD -Adapts to JE200±5V,±9Vand±12V

DC/DC converter with +5V input. Toriodal hispeed switching XFMR. Short circuit protection. PC board construction. Piggy-back to JE 200 board. Size: 3'/i" x 2" x 9/1B"H

\JE205

$12.95

MICROPROCESSOR COMPONENTS

8 080 A/8080 A SUPPORT DEVICES

INS8W0A CPU

DPS212 B-BII Inout/Outpul

DP82H Priority Interrupt Control

DPM16 Bi-Dlrectlonai Bui Driver

DPSH4 , Clock Generator/Driver

OP82M Bui Driver

DPB22B System Controller/Bui Driver

DPB2JB System Controller

INS8243 I/O Expanoer ior4a Series

INS82S0 Asynchronous Comm. Element

OP«2Sl Prog. Comm. I/O (USART)

DPB253 Prog. Interval Timer

OP825S Prog. Peripheral I/O (PPI1

DPB257 Prog. DMA Control

DPBZS9 Prog. Interrupt Control

DPB275 Prog. CRT Controller

DPS279 Prog. Keyooaro/Olsplay Interlace

DPB3M Octal Bus Receiver

OP8J03 System Timing Element

DPB3M B-Blt Bi-OiTectional Receiver

DPBJQ7 B-Bil Bi-Dlrectlonai Receiver

OPS308 B-Blt Bl-Oirectlonai Receiver

6800/6800 SUPPORT DEVICES —

MC6B00 MPU

MC6803CP MPU with Clock and RAM

MC&aiOAPJ l?BxS Static RAM

MC6BZ1 Peripheral Inter. Adapt (MCGB20)

1023*S-Blt ROM (MC6BAJ0B)

Synchronous Serial Oils ArJanler O-MDdDs DI9ltai WODEM 2:00tits Moaulator QuaOJ-SUte Bus.Trans.(MCBT2S)

MICROPROCESSOR CHIPS

MC6B50

MC6W MC6KJ MC6UGA

2B0 (76i

2BDA l'io-1) CPU (MKMBDrg

CDPIB02 CPU

»» MPU

IDMWHADC CPU-*Bit She.

MCS650J MPU w/ciuck I

INSB035N-t MPU-B Bit (6M

INS8039N 6 CPU—SJI.Chip

40N-* C,-u (256 Bytes

JON Cpu-M Byles

MPU—16-Bit

-SHIFT REGISTERS

MMSOir 1024-E

MM 5016 H 500/51

MMSOMN Octal

MMS03SN Octal

!SMv(HWA) 10M-B

-DATA ACQUISITION

LM3MAH

DATA ACQUISITION (CONTINUED)

ADCMMCCN 8 Bit A/D Converter [B-Ch. Multi.)

ADCM17CCN

DAC1KKJLCN

DAC1C08LCN

DAC1020I.CN

DAC10<2LCN

DAC12J2LCN C04W1N

I It A/D Convener (16-Ch.Multl.)

Bit D/AConv. Micro. Comp. (0.05%)

BilD/A Conv. Micro. Comp. (0.«rV.)

BltD/A Converter (0.05V, Lin.)

Bit D/A Converter (fl.OT* Lin.)

BltD/A Converter to.wv. Lin.)

JO:4kI Dynar 256-4 static IQMxl Static

16K Dynar 4096x1 Fast 256x4 Statl

MM5K1

MM5M2

MM52*0;-)l07

MM52«j.!(.H6l

MM529BJ-3A I

J4B9

UPD414/MK4027 >

TMS4044.4SNL

TMS40-15

1Dyn.200ns(iower

-PROMS/EPROMS

:I<9532)TI 32K Epl

B2S23I74S1BB) S2S115

Si'SuJtMSIial

NMOS READ ONLY MEMORIES"

MCME6710P 113x9*7 ASCII ShiilEU w/Greek

MCM66»0P 12Sx9x7 Math SymDol £ Pictures

MCM66750P 128x9x7 Alpha. Control Char. Gen.

MICROPROCESSOR MANUAL.S

DS0025CN DSCC26CN INS1771N-1

MMSB167N MM56174N COP402N

COP402MN

COP470N

- SPECIAL FUNCTION

ect LED Dm t LED Drive.

-TELEPHONE/KEYBOARD CHIPS"

MD01S5-S

J1C972 74C923

MM511MN MM57499N

DESIGNERS'SERIES Blank Desk-Top Electronic Enclosures

• High strength epoxy niDld ed eno pieces in modi a bio wn finish.

• Sliding rear/bottom panel for service and component accessibility.

• Top/bottom panels.D8D thk alum. Alodine type 12(10 finish (gold tint color) for best paint adhesion after modification.

• Vented top and bottom panels for cooling efficiency.

" Rigid construction provides unlimited applications.

CONSTRUCTION:

The "DTE" Blank Desk Top Electronic Enclosuresare designed to blend and complement

today's modern computer equipment and can be used in both industrial and home. The end pieces are precision molded with an internal slot (all around) to accept both top and bottom panels. The panelsare then fastened to W thick tabs inside the end piecesto provide maximum rigidity to the enclosure. For ease of equipment servicing, the rear/ bottom panel slides back on slotted tracks while the rest of the enclosure remains intact. Different panel widths may be used while maintaining a common profile outline. The molded end pieces can also be painted to match any panel color scheme.

Enclosure Model No.

Panel Width

PRICE

DTE-8

8.00"

$29.95

DTE-11

10.65"

$32.95

DTE-14

14.00"

$34.95

S10.00 Min. Order - U.S. Funds Only Calif. Residents Add 6% Sales Tax Postage— Add 5%plusS1 Insurance

Spec Sheets - 25*

Send 414 Postage for your

FREE 1981 JAMECO CATALOG

JaiiiiiK/m); EE3EEI3IB

PHONE

ORDERS

WELCOME

(41S) 592-8097

MAIL ORDER ELECTRONICS - WORLDWIDE

1355 SHOREWAY ROAD, BELMONT, CA 94002 PRICES SUBJECT TO CHANGE

JOYSTICKS

\ JvC-40

JS-5K 5K Linear Taper Pots S5.25

JS-100K 100K Linear Taper Pots S4.95

JVC-40 40K (2) Video Controller in case . . . S5.95

AC and DC Wall Transformers

Part No

nput

Output

Price

AC 250 117V/60Hz 12 VAC 250mA S3.95

AC 500 117V/60HZ 12 VAC 500mA S4.95

AC1000 117V/60Hz 12 VAC 1 amp S5.95

DV9200 117V/60Hz 9 VDC 200mA S3.25

DC 900 120V/60Hz 9 VDC 500mA S3.95

CONNECTORS

DB25P D-Subminiature Plug S2.95

DB25S D-Subminiature Socket S3.50

DB51226 CoverforDB25P/S SI.75

22/44SE P.C. Edge (22/44 Pin) S2.95

UG88/ U BNC Plug S1.79

UG89/U BNC Jack S3.79

UG175/U UHF Adapter S .49

S0239 UHF Panel Recp SI.29

PL258 UHF Adapter S1.60

PL259 UHF Plug . SI.60

UG260/U BNC Plug SI.79

UG1Q34/U BNC Bulkhead Recp SI.29

TRS-80 16K Conversion Kit

Expand your4 K TRS-80 System to 16K. Kit comes complete with:

*8 ea. MM5290 (UPD416/4116) 16K Dyn. Rams (*NS)

w Documentation for Conversion

TRS-16K2 -150NS $49.95

TRS-16K4 -250NS $39.95

JE610 ASCII Encoded Keyboard Kit

\

The JE610 ASCII Keyboard Kit can be Interfaced into most any computer system. The kit comes complete with an industrial grade keyboard switch assembly (62-keysl, IC's, sockets, connector, electronic components and a double-sided printed wiring board. The keyboard assembly requires t5V <? 150mA and -12V (s> 10 mA for operation. Features: 60 keys generate the 126 characters, upper and lower case ASCII set. Fully buffered. Two user-define keys provided for Custom applications. Caps lock for uppercase-only alpha characters. Utilizes a 2376 (40-pin) encoder read-only memory chip. Outputs directly compatible with TTL/DTL or MOS logic arrays. Easy interfacing with a 16-pin dip or 18-pin edge connector. Size: 3H"H x 14'/,"W x B',-L"D

JE610/DTE-AK (as Pictured apove). . .$124.95

Jcem l/;t 62-Key Keyboard, Pc Board, A —„,,_ EblU Kit a Components (no case). ... .$ 79.95

K62 62-Key Keyboard (Keyboard only) . . .$ 34.95

DTE-AK (case only ^3¥."HxU"Wx8WD)$ 49.95

JE600 Hexadecimal Encoder Kit

FULL 8-BIT LATCHED OUTPUT 19-KEY KEYBOARD

The JE600 Encoder Keyboard Kit pro\, hexadecimal digits produced from seqL to allow direct programming for 8b or S-bit memory circuits. Three additional keys are provided for user operations with one having a bistable output available. The outputs are latched and monitored with 9 LED readouts. Also included is a key entry strobe. Features: Full 8-bit latched output for microprocessor uso. Three use r-define keys with one being bistable operation. Debounce circuit provided for all 19 keys. 9 LED readouts to verify entries. Easy interfacing with standard 16-pin IC connector. Only +5VDC required for operation. Size: 3J4"H x Sli"W x Se'."D

JE600/DTE-HK (as pictured above) . . . .$99.95

JE600 Kit pc sea

K19 19-KeyKeyboa. DTE-HK (caseonl>

My).... $14.95

vxs*.»d) $44.95 .

Circle 314 on inquiry card.

BYTE February 1981 369

7400

SN7400N SN7401N SN7402N SN7403N SN7404N SN7405N SN7406N SN7407N SN7408N SN7409N SN7410N SN7411N SN7.112N SN7413N SN7414N SN7416N SN7417N SN7420N SN7421N SN7422N SN7423N SN7425N SN7426N SN7427N SN7.129N SN7430N SN7432N SN7437N SN7438N SN7439N SN7440N SN7441N

SN7 444N SN7445N SN7446N SN7447N SN7.I48N SN7450N SN74 5IN SN7453N SN7454N SN7459N SN7<160N SN7470N SN7472N SN7473N SN7474N SN7475N SN7'I76N SN7479N SN7480N SN7481N SN7482N SN7483N SN7485N SN7486N SN7-189N SN7490N SN7491N SN7492N SN7493N SN7494N SN7495N SN7496N SN7497N 00N

S N 7 ■ SN7.

SN7 ■; SN71

SN74 S N 7 ■:

0 7N

SN7.1123N

59

74LS00N

SN74125N

39

74LSD1N

SN7.1126N

44

74LS02N

SN74126N

59

74LS03N

SN74132N

69

74LS04N

SN74136N

95

74LS05N

SN74139N

95

74LSOBN

SN74141N

69

74LS09N

SN74142N

295

74LS10N

SN74143N

295

74LS11N

SN74104N

2 95

74LS12N

SN74145N

62

74LS13N

SN74147N

1 95

74LS14N

SN74148N

1 20

74LS15N

SN74150N

99

74LS20N

SN74151N

67

74LS21N

SN74152N

67

74LS22N

SN74153N

67

74LS26N

SN7.11S4N

1 19

74LS27N

SN74155N

82

74LS2BN

SN74156N

6 9

74LS30N

SN74157N

69

74LS32N

SN74158N

1 65

74LS37N

SN74160N

95

74LS3BN

SN74161N

95

74LS40N

SN74162N

ag

74LS42N

SN74163N

61

74LS47N

SN74164N

97

74LS4BN

SN74165N

97

74LS51N

SN74166N

1.20

74LS54N

SN74167N

1 95

74LS55N

SN74170N

1 69

74LS73N

SN74172N

595

74LS74N

SN74173N

79

74LS75N

SN74174N

69

74LS76N

SN74175N

89

74LS78N

SN74176N

85

74LS83AN

SN74177N

85

74LSB5N

SN74179N

1.80

74LS86N

SN741B0N

75

74LS90N

SN741B1N

1 75

74LS92N

SN74182N

75

74LS93N

SN74 1B.IN

1.95

74LS95N

SN74IB5N

1.95

74LS96N

SN74186N

9 95

74LS107N

SN7418BM

3.90

74LS109N

SN74190N

1.15

74LS112N

SN74191N

1 15

74LS113N

SN74192N

.85

74LS114N

SN74193N

B '

74LS122N

SN74194N

a 5

74LS123N

SN74195N

BS

74LS124N

SN74196N

B 5

74LSI25N

SN74197N

85

74LS126N

SN74196N

1 39

74LS132N

SN74199N

139

74LS136N

SN74221N

1 39

74LS138N

SN74251N

95

74LSI39N

SN74273N

105

74LS145N

SN74279N

89

74LS14BN

SN742B3N

2 15

74LS151N

SN742B4N

390

74LS153N

SN74285N

3 90

74LS154N

SN74290M

1 25

74LS155N

SN74298N

95

74LS156N

SN74365N

GB

7<1LS157N

SN74366N

6B

74LS15BN

SN74367N

,79

74LS160N

SN7436BN

.79

74LS161N

SN74390N

1 90

74LS162N

SN74393N

1 go

74LS1G3N

SN74490N

1 90

CMOS

CD4000 CD4001 CD40O2 C04006 CD4007 C0400B C04009 CD40I0 CD4011 CD4012 CD1013 CD4014 CD4015 C04016 CD4017 CD401B CD4019 C04020 C04021 CD4022 CD4023 CO<!024 CD4025 CD4027 CD402B C04029 CD4030 C04031 CD4032 CD4034 CD.1035 CD4037 CD4040 CD4041 CD4042 CD4043 CD4044 CD4046 CD4047 CP4048 C04049 CD4050 CD.1051 CD-1052 CD.1053 CO4055 C04056 CD4059 CD4060 CD4066 CD4069 CO4070 CD4071 CD4072 CD4073 CD4075 CD4076 CD40 7 7 C0407B CD40B1 CD4082 CD40B5 C04089

3 25 2 15 3.25

1 to

395 295

CD4093 CD4094 CD409B C04099

MC14415

MC14419

CD4501

CD4502

CD4503

CO4505

CD4506

CD4507

CD4506

CD4510

CD4511

CD4512

C04515

C04516

CD4518

CD4520

C04555

C04556

CD4566

74C00

74C02

74C04

74C0B

74C10

7-1C14

74C20

74C30

74C32

74C42

74C4B

7JC73

74C74

74C85

74C89

7-1C30

74C93

7.1C95

74C107

7aCl51

74C154

74C157

74C160

74C161

74C163

74C164

74C173

74C174

74C175

74C193

74CI93

74C195

74C922

74C923

MM80C95

MM80C97

2 95 2 49

2 25 12 95 1 2 95 1295 12.95

8 95

74LS00

74LS164N 74LS165N 74LS166N 74LS168N 74LS169N 74LS170N 74LS173N 74LS174N 74LS175N 74LS1B1N 74LS190N 74LS191N 74LS192N 74LS193N 74LS194N 74LS195N 74LS196M 74LS197M 74LS221N 74LS240N 74LS241N

74LS245N

4.95

74LS247N

1.10

74LS248N

1 10

74LS249N

1 69

74LS251N

1 79

74LS253N

9B

74LS257N

98

74LS258N

as

74LS259N

2 95

74LS260N

.69

74LS261N

249

74LS266N

59

74LS273N

1 75

74LS275N

A 40

74LS279M

59

74LS283N

1,10

74LS290N

1.29

74LS293N

1.95

74LS295N

1.10

74LS29BN

1.29

74LS324N

1.75

74LS347N

1 95

74LS348N

1.95

74LS352N

1 65

74LS353N

r.65

74LS363N

1 49

74LS365N

.99

74LS366N

.99

74LS367N

.73

74LS368N

.7 3

74LS373N

2.75

74LS374N

2.75

74LS375N

.69

74LS377N

1 95

74LS3B5N

1.95

74LS3B6N

65

74LS390N

1 95

74LS393N

1.95

74LS395M

1.70

74LS399M

2.95

74LS424N

2 95

74LS66BN

1.75

74LS670N

2 29

81LE95N

1.99

81LE96N

1.99

81LS97N

1.99

81LS98N

1 99

LINEAR

SH05

BM06

BMG

M105H

M10BAH

M300H

M301CN/M

M304H

M305H

M306H

M307CN/H

M30BCN/H

M309K

M310CN

lD/CN/1

M312H

M317T

M318CN/H 9N/H

M320K-XX"

M320T-XX

M320H-XX*

M323X

M324N

M339N

M340K-XX'

M340T-XX

M340H-XX

M344H

M34BN

M35BCN

M360N

M372N

M376N

M377N

M380CN/N

M3B1N

M3B3T

M386N ■

M387N

M390N NE531V/T NE5 55V NE556M NE561T NE5S2B NE565N/H NE566H/V NE567V/H NE592N

M702H

M709N/H

M710N/H

.M7 11N/H

M715N

M723N/H

M733N/H

M739N

M747N/H

748N/H

M760CN

M131DN

LMI414N 1

LM1456CN/N

MC14B6N 1

MC14B9N

LM1496N

LM1556N 1

LM1600N

LM1B20N

LM1850N

LM'BB9N :

LM21 1 IN

LM2900N

LM2901M

LM2917N

CA3013T

CA3018T

CA3021T

CA3023T

CA3035T

CA3039T

CA3046T

LM3053N

CA3059N

CA3060N

CA3062N

LM3065N

CA30BON

CA30B1N

CA30B2N

CA30B3N

CA30B6N

CA3089N

CA3096N

CA3097N

CA3130T

CA3140T

CA3146N

CA3160T

CA3190M

CA3401N

MC3423N

MC3460N

SG3524N

CA3600M

LM3900N

LM3905M

LM3909N

HC4131N

HC4136N

HC4151N

RC4ig4

RC4195

ULN2001

ULN2003

SN75450N

SN75451N

SN75452N

SN75453N

SN75454N

SN75491N

SN75492N

SN75493N

SN75494N

249 2 49 2 49

RETAILSTORESOPEN MON-SAT STORE 1310 "B"E. Edlnger STORE 674 El Camino Real #1 Santa Ana, CA 92705 #2 Tustin, CA 92680

Showrooms, Retail, Warehouse Specializing in Systems

AEMVNCED

COMPUTER PRODUCTS

Superior Color, Music, Sound & Graphics & a Powerful Extended Basic-All Built-in. Now! Special TV. Adapter lets you use your existing T.V. set as a computer display.

$499.00 d

Console only.

BECKMAIM

Digital Multimeters

~ MODELS TECH WO AND TECH 110

,- v.01*1

fcS nO ChM(olMo«i5-I>tUCM]10nassiUWrt C- jA"^ lealu'cs 7 funcnuris J9 (inots piu»0l5% V«

%

^\ VC-20 1 Vinyl Cnrry.ng Caso.

ff£-\ DC-202 DoIliib Ca"ying Cast.

'Pb'-V HV-211 Hifjn VoliuOi* Pi ubo

\ J\ fip-"' RPp'°lJ»

_lrt\ Ct-231 ACCuifBUlClB-ni)....

■aaV?,' ni .Jdl fli.li,.A Tncl I o.i/l KiF

4&

ff|" MUSIC MACHINE 9®

mtm with g voices;

• rJEWU^slatmSlati

AY3 8910s ID vi oentraiajby meALFBoanl •

• APPi£i« nanwiiO

*ss:h«eit c»ko iEirt-3

$129.95

FLOPPY DISK DRIVES

MR B5t-5W,40 tracks .

Shuga-I SA4O0-51." 35 track:

Shugail BOO/BOiR B"

Siemens Shugart Compatible

FDD-120-BD PERSCI MDdel 277 Duol WANGO.'SIEMENS 5'*" Dnve MPI B52 5'-" Dual, ... WANGO/SIEMENS 282 Dual WANGO/SIEMENS B2

. 279 00 . 295 00 ..475 00

42g00 1 195.00 29000 348.00 .395 00 . 290 00

ESCCONTINENT&L SPECIALTIES Mcdel LH-3 40-cfianiiel Logic Homloi . . 58500 Model LM-1 Logic Monitor ,.. 6000

MudelLM-Z Logic Monitor 14700

MAX-IOQ 100 MHZ Portable freQuency Counter

Model LP-I Digital Logic Piobe

Model LP-2 Economy Logic Piodc

Model LP-3 High Speed Logic Probe

Model LFK-I Logic Probe Kit

Model LTC-l.lTH Logical Analysis Kits 220/250

4900 5000 2800 77 00 2195

Proto Clips

14-Pin Clip

16-PmCliD PC'16

24-PinCHp PC-24

4Q-Pm Clin PC-40

Proto Boards

1695 PB-104....

10.00 PB-L'03 ...

21 00 PH-203A..

25 00 PS-203A-K 43 00

SEMICONDUCTORS

^rSPEAK!^ DIGITALKER

Speech Synthesis System

The DIGITALKER is a speech synthesis sysiem consisting ol multiple N-channei mOS inle

chip ISPC) and speech ROM and when used

• Compieleiy independent system, r

requiring a processor controller

• Designed to be easily interlaced I

popular microprocessors

• 256 possible addressable express

• Mate.- lemale. and children's voice:

speech

dynamic ROMs

• TTL compatible

• MICROBUS"- compalib

DIGITALKER'" DTI000. S»lf contained board that-with just a npaakar end a pow or supply-can rsKIa off any desirad combination of 144 word.. $4B5.0O

DIGITALKER'" DTtOSO.Chlpaa tf or building Dlgltalker Inloyour own evaluation design.

OT National

£A Semlconductof

$79.00

i Apple II. 16K or Apple II. Plus $990

J DISK SYSTEM SPECIAL

Apple II Plus W/48K Supermod Video Modulator

Disk II w/Controller Integer Based ROM Card.

Reg. S2.22O.O0, ACP Price S1819.00 SAVE S401.00

Hi-Speed Serial I 0 Centronics Punter I/O Applesoft II F urn ware Apple Clock tnlrol X-10 Syslem Intrd X-10 Controller All Music Syninesirer t6 Ch Analog Input 2 Ch Analog Output 13-Key Keypad Visi-Calc

S18900 18000 18900 ?69 0 17995 26995 25995 24995 164 95 11995 12500

DS65 Digi-Seciw Apple Graphics Tablet DC Hayes Modem II

fty*. II vtCrjfii'oi-* & Dos 3 3

Disk ll

Pascal Lang System Parallel Punier Card Communications Card Business Sattwaie Pkg Corvus 10 Megabyte Drive

462500

S349 00 6750(1 34995

59500

45900 450 00 16500 18900 62500

integer ROM CaiQ

PrOloCard

M& H Modular

Sanyo Cassette

16k Upgrade Kit

Desktop Plan

8 Floppy Controller

Heur.st«:s SpeecniaD

FtomptuS +

Superiaiker

Cashier

S1B900 2i95 2S95 54 95

5495 98 .V 350 j,' 17900 16900 27900 25000

NEW APPLE PRODUCTS

i "APPLE FAN"- Cures thermal pmUems (rom owrcrowried nvictiics ocsigneo jon leany lor Apple S4995

i "BITS" - Np« 8 0k24 Viaerj Board for Apple Compieleiy coniMtiWe wiw Pascal S32995

> "BAR WAND" Hentetl PacKaid H.EDS-3000 Bar Cede

mterlxed tc ,',(.:■:■ S199CO

> "SEC APPLE A/0' - 3 Channel A'P Interlace compieleiy

asseinlilrjO arid tested S99 50

i 'VISTA APPLE BO TRACK DISK DRIVE" Floppy ArKi-onirji

• DOS 33 U

: ?3 in

! storage in ll

S6500 ,S550QG

Apple 5v«- 80 IPI

S459C0

APPLE FCRTRArT

S175 00

APPLE CRYPTEXrior

umwtaM

S44900

LVUXAPPLE MODEM

new madeoi lardnect

S2B9 00

DZ:.A2 ■ Graptiw Inteit

ce Caid by Base 2

SIS99S

» 8" Oisk Dims lorAPpie Controller. D0S.T*o B'

dnves caOneiard cable S145000

■ -MICROMODEM" - DC. Hayes . S31995

* "OIGlSECTOfl- Converts video input to Hi-Res

sraplws. ... S34995

• VlSiCatKeyparh NunOeric keypad *ith -nvc ESC.

- and - keys lor VrsiCaic compa tibilily S16900

• Mcontain Harflwaie Music Bo3"d.te

16ctunnels

■ Controller 1 1 Revision KiL 20°'u Overall processing

disk ruiidlirg AOditioiul ere decking.

Improved manual Vend* Hie expanded S14500

• Pascal Revision Kit Adds executive and

chaining ap»t)ilit>es 10 Pascal envi/onmenl S6500

• Manila in Hardwaie Eaparsion oisssis 9 noie siols

laApok! Haid*are cr sottwaie selectable.

includes powei supply .... Avail Soon

• Smart Term Apple HO ( ?4 VCeoCaiO .. Avail Soon

• S>mlei X-10 Avail Sew

• Apple Silenlyoe WithAppc Iniellgent interlace

Card S54900

• NEW! Catironia CwnsUler Systerrs APPLE Clock.

Only S12495

• NEW Z-BO Stftarfl lor APPLE CPM 22 & M BASIC

50 ... S32500

• NEW Ciilorna MCfLumlucts Keypadtrx

APPLE SI7500

NEW APPLE SOFTWARE

1 CmSSTRIKE ~ Aim** M I

Alan an dish

2 HllSlKkHirUUulilll-l

3 "ll« Cmlur- Apple I Ui

same. 'Gaiai/' ..

A 'Bill limb' - Ht-Res sim.[aiio arBSkeelSriccij^ Same ai 5.'April TiiPiiMTf Kktfi" g-Nrr-OdSTNllur 7 HEW) Applo 7.-60 CPyM SotlMfl

n GurrHgtil

it S2995

. S74 9S

$6495

Call tor Price

A ATARI 800 & 4oo

Personal Computer System

ATARI 800 $825.00 ATARI 400 $449.00

ATARI SOO Includes: Compuler Console. BASIC Lang. Cartridge. Education System MasterCartridge. BASIC Language Programming Manual. 800 Operator's Manual w/Notebook. 16K RAM Module. Power Supply, TV Switch Box.

i Siiiih Citusi Fntrrai

Ox 0;~e

Supei BicikOul™

Music Co^crar Super Bug™

6900

JbOfJ

Sim Ekxtt-cil,

l»lc IimiiI hi|nwC>iuRti

ij.Jctc 5=-,iC P-o;-3—■-■;

BASIC 0S"< Progiarns HIDl llBB(

Ek RAU Ifprxrt MMue I6K RAM Memory MorJule

Dr.vioq Conircier Pan

Caddie Crone*' Pa"

350D

SINGLE BOARD COMPUTER SELECTION GUIDE

FflOCESSOP ACP PfilCf. ENCLOSURE H0AR1I

6502 16(100 Add 2995 SC-SOCK

6502 239 00 Add 3995 AIM 65

ZBO 40900 WA CosniacVi

PROCESSOR ACP PRICE

ACP'S COMPUTER PRODUCTS & GADGETS

You won't believe

your ear bones..

THE BONEFONE

• SKIERS

• JOGGERS

• SKATERS

• CYCLERS You must hear II arKj feel it to believe it!

€

it $65'

QUARTZ LCD WATCH

WITH SNOOZE ALARM

The looks and funclions ol the expensive models at an affordable price.

NEW!

6 FUNCTIONS

• HOURS •MONTH

• MINUTES • DATE

• SECONDS • DAY

An Outstanding ACP Value ONLY $21 .95

LCD CALENDAR CLOCK GEAR SHIFT KNOB

Time and Date Digital Display with Backlight for Night Use.

.™F„«c,P NEW!l

$26.95

P.O. Box 17329 Irvine, Calif. 92713

Direct Order Lines: (714) 558-8813

(800) 854-8230 or (800) 854-8241

FOR INTERNATIONAL ORDERS: 1310 E. Edlnger (7141 9530604 Santa Ana, CA92705 TWX: 910-595-1565

370 BYTE February 1981

Circle 315 on inquiry card.

COMPUTER rPRODUCTS

1ESE333E

• S-1QO 32K (uses 2 ll 4)

ASSEMBLED

450ns 459.00

250ns- 489.00

Bare Board 43.95

Bare Board w/all parts less mem. 99.95

Kit w*"

450ns. 429.00 250ns. 459.00

MODEL 2065

64K DYNAMIC RAM

MODULE $600.00

• DesijnM ti> IEEE Pmwiscd S-100

• Sucpnti IMSAI-typc fiml Mrets

• G:--.Hl-:-- /. th M'«:t .ll» 15'Jrll} (IT « j

Z-BO Msnl S 100 system

prowling pocemoMnnsiarenl ■ <

iHieWts win wb

• B*'*'«'MI system aflows system

BSsir

The VISTA V-80 TRS80 ADD-ON

Disk Drive System

SALE 5299.00

■'." i-.il-> t.irrr, ,ii Mi (iham;;;

._ SALE ^Bk

■ $299.00 fl^

THE VISTA V-200 FOR EXIDY

ATTENTION VIDEO HOBBYISTS!!!

* BOX BUILDERS

* USE AS REMOTE TUNER/TIMER

* FULL SCHEMATICS AVAILABLE

* FOR ONLY S5.90! - FREE W/PURCHASE

NEW, UNUSED COMPONENTS

f mm The RCAV0T-2OI VMeocassclle Recaider

1 UHF.VHF Turin SitjassemWy Aitn all KmUs

jtJvdfnDp^fliiilo S59.95

2 HI MrKublo Bill. Aud>0 & VOW iliPUIS

Ctunflcij.if j ftiinin S3B.93

3 DiOriaiCHk MnrJuie AMrPM f mnewcm

Rr.nlr.,1 f,.wil S19.9S

■i 300 rihm tri fi'Ohm Malctiw] $ 2,40

□r SZOT SI 23.34

MfthftutMMMM $74.95

Please Call For Volume Discounts

RAM BOARDS SPECIAL

16K Allair Mils Dynamic RAM Boards Assem A Tastod S119.95 Untested S95.00

16K

LOW COST FLOPPY DISK SUBSYSTEM

Semens fdd i?ob i2j vista Floppy Coniroi

lor|S-100i.C;im;. Power Supply & Cable CP/M Disk Qpfrrallng System Assembled 4 Tested

Walnut Wood Sides SI 400.00

* CHECK DUf) FIOPPT OISK PRICIMG ON THIS PAGE* SAVE $300.00 IS1799.00 VALUE)

WATANABE MIPLOT

IMS ST AT I

8KSta!ic 16K Static 32K Static

cRAM I5A

250 ns. S209.00 S449.00 S729.00

RDS

450 ns. S189.00 S399.00 S629.00

CENTRONICS PRINTER

Model 737

• Centronics complete printer Tlie 737 has everything. Check and compare the features New low price $835.00

..0 SD SYSTEMS BOARDS

5* TAKE 10% OFF! kit ,

] S26SCQ

:l 299 00

31900

E-aando PROM SD1O0 Comouler SD200 Comtime*

.SSEM ; 349.00 399 00 449 00 ■1 - 9 00 429 00 225 00 699500 7995 00

6800

MODEL N

9600A

9609

9601

9602

9603

9627

9629

9629A

9630

9610

9650

9655

96103

96702

MICROMODULE'" PRICE LIST

3 DESCRIPTION PRICE

5ingle Board Microcomputer S495.00

Advanced Single Bd Comp (68091 595 00 16 Slot Mother Board 17500

Caid Cage 75 00

8 Slot Moittci EJoard 100 00

Power Supply 275 00

DC Input Power Supply 325 00

Ui.MvPi-oloBoaid 39 00

195 00 49 00 250 00 250 00 29500 32500 395D0 695 00 395 00 68 00 395 00 395 00 550 00 27500 35000

Auin Proc/Memory Module Buffeted UliHly Proto Board 32K FJPROm/Ram Module EPROM Proyrammmo Head 16 Channel Parallel I/O Modi. Senal.Parallel I/O Module c RAM K

32KS1S 32K SI3HC R

150ns rl 200ns

rU31^r57TT77TT7TT

TRS 80 16K-UPGRADE KIT

$49.95 TRS-80/APPLE $49.95

MEMORY EXPANSION KITS,

4116's, 16K (200/250 ns.)

8 pes for S49.95

w/instructions S jumpers

Call For Volume Pricing

* Special: TRS80 Schematic S 4 95

* Expansion Interface Schematic .. S 4.95

* Expansion Interface Connector... 7.95

EXPANDORAM II MEMORY KITS

* Bank Selectable * Uses 411 6 200 ns.

* Write Protect -g,* Power 8VDC.±16VDC

* Phantom n^ces * Up lo 4 MHz

Expando 64 Kit (4116) Assem. a Tested Add S50

16K S269.00 48K S435.00

32K $349.00 64K S505.00

PERSCI MODEL 299B

DISKETTE DRIVE

3.2 Mbytes capacity

(unformatted), max. seek

time 100MS.

ACP Price $2,199.00

uv

EpronV' Eraser

Model UVs-11E S69.95

Holds 4 Eprom's at a time

Backed by 45 years

experience.

Model S-52T... $265.00

I Industrial Model

EMAKO-20.. Reg.$777.00 $599.00

lera • Uppe// Low er Case 4 5" 10 9.5" Adjustable - 80 col/40 col double width-Full 96 Char.ASCII

EMAKO-22 $799.00

VISTA V-300 PRINTER 22

25 CPS, Full Character

Daisy Wheel, 136 Column

Model

NO. FP1500 $1995.00

BASE II PRINTER

BO Column Impacl Printer ___——"~~"*fc

• 60 Unes Per Minute /\f ^LV

• 115/230 VAC. 50 jA _^"~~~--i or 60 H7. rzT'^^-^^^A

• 72,80.96. 120 or ^^*^Z-\^^m^*J _ 132Char/Une ^^^^T^^^Z-^"^

• Seil-Tes, S^ch ^<^^-^^REG S693 M

WITH ALL OPTIONS ACP PRICE $599.00

Oplion "M" Terminal Screen Bullet 11920 Char I S50 00

Ofilion "5" Htgh Speed Paper A,iv:nu -■ f. Graphics. . ..50.00 OpuonT'Tractor Feed . .. .5000

^SoTz^OA/^O^oTpTJ^OARD™

* Or> board 2708 * 2708 Included (450ns.)

* Power on tump * Completely socketed.

• 2-80 Assembled and Tested $18500

• Z-80K.1 SI29.95

■ Z-BO Bate PC Board S 34.95

#For1MHi Speed Add SI 5 00

8080A Kit S 99.95

8080A Assembled 5149.95

S-100 MOTHERBOARD SPECIAL

8 slot expandable w/9 conn.

reg S69.95 NOW S52.95

SIEMEN'S FLOPPY sale

. Spr-nal buy wnile supply lasts SIEMENS

..Vi.i.JhDouble-Denst.y W29 00

a r(r, Qay W.itranty SHUGART

• CHECK OUR FLOPPY DISK PRICING' s™ no

ON THIS PAGE

ACOUSTIC MODEM £*%**&

NOVATION CAT'" C-300 Baud ^^J^-Q Qe

Bell 103 Answer, Originate -——i^O

'D' CAT MODEM NOW AVAILABLE $199.00

MONITORS

Sanyo i?' n.iu Display Zenith 13 Cum Montw i99nc

DVB II7CX, S3?500 MGA 13" Color TV 34900

Motorola 12' H*jii Resolution VAMP 19" Color Monitor 57500

22 MM/. OEM Model VAMP I5_ CoW Monitor -14900

*M3000-340 21900 Sanyo 9 I69 9S

Motorola 5' Sanyo 15" 2/900

Wriirt nHlOD ISFirOtMi 119 95 Imlei W 13995

DATA BOOKS • COMPUTER BOOKS

1980IC Master . S5995

INTEL Data Book ..... 7 50

INTEL MCS 85 Manual . 7.50

SALE • OSBORNE BOOKS • SALE Sale

Introlo Micros Vol. 0 . . 12 50

. 12.50 16O0 27.50 18.50 IB 50

SALE • SYBEX COMPUTER BOOKS • SALE MOSCa ■ Sra&a

FIRST TO OFFER PRIME PRODUCTS TO THE HOBBYIST AT FAIR PRICES!

1. Proven Quality Factory lesled products only.

2. Guaranteed Satisfaction

3. Over $1,000,000.00 Inventory

1981 CATALOG AVAILABLE SOON.

Send $2.00 for your copy o f the most complete catalog of computer products. A must for the serious computer user.

MICROPROCESSORS

F-3I3B50)

2650

CD1U02

6SO0B2

r> |y

H;

1995

6B02P

1795

B035

1995

B755

1995 . 6995

.37 95

6086

6995

ADVANCED SUPPORT

AM95II

An

i Pieces'.

3i ... 175 00

9512 Ai

i ,.. 175 00

9513 Ut

79 95

AM9BI1

UN

r IB 95

AM9519

jni

eisailntci

upt .18 95

Z-80SUPPORT CHIPS

2 5 IV

. B75 12.95

2B0-DMA 25 M

ZBOA-DUA 10 MHi 36 95

ZBO-SlO/0 2 5UH2 35 95

2B0A-SIO/0 40MH2 3910

ZBO-SIO/1 25MHI 3595

ZBOA-SlO/l 4 0 MHi 3940

ZBOSlO/2 2 5MHI . . ...35 95

ZSO'StO/2 'lOMHi 39.10

8080/8085 SUPPORT

gi55/BI56 I/O 2,1.95

B755 I/O with Entom ... Bfi.95 8202 Dyn Ram Con I ,., 31 95

B205/7.'iS I3B Decoder 3 95

B21J B bill/o 2 75

B214 Pnonlylot 5 25

8216 Bus Duvet 275

B221 Clock Gt-n 2 95

B221'1 HMHi) .975

B226Bns Dnver .. ... . 3 95

BT26 BusDiiver . .. 2 95

B22B Sys Control 5 50

B23B Sys Coni. 5 50

B25t Ptog I/O 6 95

8253 Inl T.met 12.95

8255 Prog I/O 6.50

B257 Piog DMA 16 95

8259 Pro?) Inl 17.95

B27SCRT Controller 19.95

B2/9 Proa Keyboard 15.95

6800 SUPPORT CHIPS

6B10 128. B Ram 4 75

STATIC RAMS

1-2.1 2599

21L02 J50ns /e^uE^ 21L0? 250ns ( ,-^0^ 2112 1 V£^

1 30 1 25

3 75 3 65

i 55

2 95 2 85

.' t,S

21011

290 270

21 11L-250ns 11015)

6 50 5 95

5 50

2ii1L'150ns. (1045)

5 50 525

4.75

1014 250ns

895 7 50

G90

5 95 5 95

4.75

EMM420OA

9 75 8 75

795

EMM4403

7 95 7 25

6 ■; 5

1095 1025

9 25

AMD9130/31

1295 1195

10 25

1101

195 175

1 25

P2125/93125 (DSniJ

995 B 35

825

651B IK . I CMOS

7 95 795

7 25

2I.17LovjPowci.1K Slall

19 95 1B 9 E

1695

93415

995 895

8 50

TMS40d8

11 95 10 95

10 50

DYNAMIC RAMS

416/41 1(, 16KH6 Pin)

8.75

Set ol8 416s

49 95

41 taSKlIB Pm)

6-95

4050 1k , l (IG Pm) ..

.1060 IK* M22Pini.,..

. 495

2104 IK 1 1 (16 P.n)

4 75

4027 4H > 1 116 Pin)....

5261 1 95 C:A\C 1 103

5262 .. 1 95 OH-r\ 4OO8L

1 95 4 95

5270 A 95 RAMS 6605

5290 . I?4SS1 59.95 6002

1 50

SOCKETS

»PI„s

Lo-Pro Sotde

| Wi.e Wrap

3 Level

■tail

Tin

Gold

0

19

36

59

16

20

38 59

62

20

29

.69

99

22

24

1-10

2-1

ja ■13

110

120 1 49

36

58

1 23

1 69

•10

60

1 10

1 89

ZERO INSERTION FORCE

16 P.n S550 2.1 P.n S

50 40 Pm

510 25

FLOPPY DISK I/O

1-01 A'B N

■ ■■:■'.

13 50

r-i-iHf tin Cob

DLrTJI 30D Rco

DL707 30E RM

FND357 357 Hcd

FND501 50D Red

fNDiOJiSOOl 500 Red

FflD5C'7!5lOJ 500 RM

LED READOUTS

Oic.-iP'isri

Conim Cairwte Conim Callow ICtmm CalHode Crjrrnr. Ann*

1791-01 OualFiDppy 3695

A/D CONVERTERS

8700 a bit Binary

8701 10 Inl Qmary 8703 A till TS, 9400 Volt 10 Freu Conv B750 3'j D.y.1 BCO 140BL6 6 bit

DAC 100 15 95

TV CHIPS/SOUND

AV3B50O-1 6 Games BAV 4 95

AV3B5 1 5 Color Conve.iei 2 95

AV3B603 I Roadrace Game B 95

AV38606-1 Wipeout Game 9 50

AV38607-1 Snonnncj GaMer, a 95

AV38910 Saund Gen^ratar 12 %5

SN7647 7 TlS«rjndGenfiraioi 3 95

MM 5320/21 TV Syncn Ge n 9 95

MM5369 Piescaler 3 95

LM1BB9 RF MoeulalQi 395

MM571O0 NSCC0I01TV . 6 95

MM57I04 Clock Gel), 3 75

RF Modutalorw/Audio 8 95

WAVEFORM GEN.

MC4024VCO . . .. 2 9!

LM566 VCO - .- 19!

XR2206 Function Generator 5 2;

SHIFT REGISTERS

MMSOOH Dual25 51

MM5056N Dual 256 2 9!

MM5060N Dual 128 29

25iOADLiai 100 19

3351 40 i 33570uai 9403 1 6 x 940B 10 B

CTSDIPSWITCHES

CTS206-2 1.75 CTS206-7 1 75

CT3206-4 1.75 CTS206-B 1 95

CTS206-5 1 75 CTS206-9 1 95

CTS206-6 1.75 CTS206-10 1 95

CONNECTORS(GOLD)

DB25P IRS232I . 325

22/44 WAN. S/T. KIM 43/86 W/W. S/T. MOT 50/100 S-100 Connector 50/100 SIC

6821 P 6B2B P 6B34-1

6645 H

5 9'j

SHIFT REGISTER SALE

6502 SUPPORT CHIPS

6520P1A 7 50

6522 Mull . ... 1 1.95

653O-0O2.OO3OO1.OO5 21.95

6532 .. ... 19.95

275B-5V . 5203AO . 5201AO IM 5610

SALE 8223 32 1 B2S115512 .6 B2SI23 32 • 8. B2SI26 256 < 1 82S129256 |4 82S1305I2 »1 62523 82S13!

8 2.95

CHARACTER GEN.

2513O01 (5V|Ucc 2513005 (5V)Low 2513-AOM3 (5V|L MCM6571 MCM6571A ,.,, MCM6571 MCM6575 .

UARTS/BAUD RATE

Ay5iO>3i5V 12VI

A¥i.10HA/1612l5-14

A¥!il0i;>A:iaf.3(&Vi

FND530 500 Ijrrtn Comm Cathole

149

NOS03(80fJi 800 Ri.-d Comm CatlioJe

175

NAKED PC

MJB07J61Q) BOO IKO Con in Anode

tPSOflZ-n.lO 600 to) 4*7 HeMJeomai

Z-BOCPUirthacai s34 y5

1^082-7300 600 ReO 1 > / Sd Dig.t HHD

BOBOA CPU 34 95

■1*,5082-7ni 300 RoJ Canm AnOt

75

8K Stat-cRAMtLOgosj . 24 95

JU05 - RbI Arrays ■ 7

795

11308 2/0 RM Numencat Dssa,

MJ95

32« Slatrc RAM 12 114i 29 95

1L309 2/0 Hnl Nu"¥ji-j 06W-

99^

BK Eorom 1270B1 . 24 95

1095

1702 Eorom Board 300C

595

2708/2716 Ecrom lllhaca) 34 95

,<Afii-A 270 Red AltmKurTcm:

895

2708/2716EpromlWMC) . 3000

WNJOfil 300 IWJ Comm Annie Bgm DC

125

Hcnltimo Clock . .34 95

LAIJ3062 300 FBO Conmi Ano* Lfti DP

125

ACPProloFJd ISMConnl 27 95

.AN30C3 300 Rid Ovtnlrw CA LillDP

125

Vector 8800 Proto 22 20

LArl3D61 300 Kb! Comm CalWK Rem DP

125

(AN3051 300Gu«n Contin Anode R-omDp

199

ACP Edender w/Conn JB.95

»m052 300 Cittn Cunni AnnoeLtnDR

199

Video Interlace (SSM| 31 95

(AN305J 300 Gr«n O.'.-rnw CA.LfflOP

199

Parallel mtedace iSSM). 31 95

WN3054 SOOCrwn Comm CalniHe Riont DP

13 Slot MotnerBoard iWMCl 32 95

1AN30E1 300 V-■:.:» :.:'• m An* R.gtil DP

9SlotMollier8oardf//MC> 29.95

IAN30B2 10 0 Ytnow Cnmm Anidf leiiOP

210

aSIOIMoHiene.oandablel 3495

KAH3083 300 Yellow Iwrttoa CA.UK OP

210

210

WMC Floociy PCB 34 95

IC SPECIAL PURCHASE

COMPUTER SPECIALS

LF I350BJFET Analog MuiliB bit

B95

lCM7045°iec.sion SlocWalcn ICM 7205 CMOS LED S!OGWai(.h/r.mer ICM 7207 0-,c.llator Controller ICM 72DB Seven Decade Countec

2395 19 95

rtlScoo|rtSi

0»3 UST SALE

iCM 7209 Clock Generator

6 95

195

Pa catM.croeng.ne 1995 1595

AV-S-3507-IOMHiDVM

SPX33 0oloCoupter

3/1 00

14BB.'14B9 2/1 99 lM 3302

3/1 99

MK5D'4Calc 3/199 LM 1558

3/1 99

74SB9 3/199 PC413B

2/199

Tioncom T-200 595 525

2/1 99

MC1372 1195 COM 5027

3995

MM529B-4/VB 2 95 COM 5037

4995

LM377 125 DAC 100

1595

VERBATIM

DISKETTES

SOCKET SPECIALS

100% CERTIFIED ERROR-FREI :

20 Pin wiw-2L 75

■ is: turns DODDLE DEHSIIl SlKCiE-SUED i'.

E BO* 10

22 P.ns/I 15

5?5 Dl SgriStlo-MKISGO (C i35 10 10 Mo>t tum NS AMt «B

TERMS; Use cbech.. ■'. AMEX. CB. or COD CO 25"d denosit CHarneOrd

9 95

;.-. 95 ...s.es

dtCKS CCJDU S [EG DOUBLE 0EMS11v V.

KEYBOARD ENCODERS

■ I ICON CI»1lll(D [SKEIliS

FM0fl-0i Son S-nnf OW15.H 3rjp S335P

'D60O li 3,1 H.irrJ Sifijif Densm 5rv.i! 3350

'0B0? 01 Sott 11W* De*if 1'Jv " BO

ftjiiw 01 Sot Daefc ^ii-n Dixjy" Densilv i'*o j*bo

VOLUME DEALER PRICING AVAILABLE

WE ALSO STOCK DVSAN-CALL

i FOREIGN Add 10°« 5 nandtiny COD'S SI B5ei

RETAIL STORES OPEN MON-SAT 1310 "B" E. Edlnger STORE 674 El Camino Real

STORE 1310 "B" E. Edlnger

*1 Santa Ana, CA 92705

Showrooms, Retail, Warehouse

«2 Tustln, CA 92680

Specializing In Systems

P.O. Box 17329 Irvine, Calif. 92713

Direct Order Lines: (714) 558-8813

(800) 854-8230 or (800) 854-8241

FOR INTERNATIONAL ORDERS: 1310 E. Edlnger (714) 9S3O604 SantaAna,CA9270S TWX:910-b95-1S65

Circle 315 on inquiry card.

BYTE February 1981 371

SB V S& MICRO IV I. SI. S>U£S

D£/IAS ■□ DEALS □ 0£>US

SHOP HERE AND

(7

10

(MINIMUM ORDER $10.00)

This is ABSOLUTELY the LOWEST PRICE EVER for a Hi Speed (300 NS) LO-LO Power 32K RAM, 4K by 1 Chips are organized in Selectable Banks

• Extended Address Lines A 16 - A17 • Phantom Line * 9 Regulators

SCHOOLS

DIP SWITCHES p°s. PRC.

4 .88

5 .92

6 .95

7 .99

8 1.05

9 1.15

10 1.19

.10 .12

.13 .15

PINS PC WW

8 14

16 .16 .19

.18 .21

.22 .26

.32 .37

.34 .39

18 20 24 28 40

AMP - Need we say more? There is a difference in sockets! These aren't the lowest prices you can find. But, if you've been"burned"before by bad connections in your computer, a few pennies for the best is worth it!

.45 .52

RESISTORS .02 ea!

(100 PACK) VM

1.0 4.7 6.8

10

15

22

27

33

47

68

75 100 150 220 330 470 680 1K 1.5K 2.2K

2.7K

3.3K

3.9K

4.7K

6.8 K

10K

12K

15K

18K

20K

22K 24 K 27K 33K 39K 47 K 68 K 100K 150K

220K

330K

470K

680K

1M

1.5M

2.2M

4.7M

10M

WIRE WRAP WIRE

Packed in 500 Lot Bundles

(Length includes 2" x 1" Strip)

Color- R, Bu, G, Y, Bk, W

50 ft. $1.65 - 100 ft. $3.00 - 500 ft. $9.50

2.5-3.25 4.0-3.75 6.0-4.75

3.0-3.35 4.5-4.00 7.0-5.00

3.5-3.50 5.0-4.50 8.0-5.50

10.0-6.50

WIRE WRAP TOOL $5.95

=H

5:

6 Amps 125 VAC

7 Amps 30 VDC

DPDT STANDARD TOGGLE ST21 (ON-NONE-ON) ST22 (ON-OFF-ON) ST23 (MOM ON-OFF-MOM ON) ST24 (ON-OFF-MOM ON) ST25 (ON-NONE-MOM-ON) ST26 (ON-ON-ON)

HOBBIEST

LM323K 5V 3A.

REGULATOR

$5.50

TAB MOUNT

7805 +5V 1A

7905 -5V 1A

7812 +12V 1A

7912 -12V 1A

$1.25

♦ GOLD ♦ S-100-CONNECTOR

Tlor Better

SOLDER TAIL

WIRE WRAP

$2.50 $3.25

DIP PLUGS

PART* PINS

08DP 14DP 16DP 24DP 40DP

8 14 16 24 40

.40 .55 .58 .95 1.50

Socket and Dip Plug priced based on gold not exceeding $700 per ounce.

CONNECTORS

DUAL

ROW .100

CARD EDGE

PINS

PRICE

PINS

PRICE

20

2.35

20

3.35

26

3.00

26

3.80

34

3.85

34

4.65

40

4.50

40

5.50

50

5.50

50

5.90

RIBBON - 20 to 34 @ 1.00 ft. 40 & 50 <a> 1.30 ft.

CRIMPING 2.00 / CONNECTOR

PRICE

OEM'S

Z-80-A

$6.95

4MHZ Beastie with extra instructions!

Z-80 SUPPORT

CTC - $6.55

SIO - $25.50

PIO - $6.50

DMA - $18.75

All 4MHZ (who wants 2MHZ?)

74LSXX

74LS00 74LS01 74LS02 74LS03 74LS04 74LS05 74LS06 74LS07 74LS08 74LS09 74LS10 74LS11 74LS12 74LS13 74LS14 74LS15 74LS20 74LS21 74LS22 74LS26 74LS27 74LS28 74LS30 74LS32 74LS33 74LS37 74LS38 74LS40 74LS42 74LS47 74LS48 74LS35 74LS54 74LS55 74LS73 74LS74 74LS75 74LS76 74LS78 74LS83 74LS85 74LS86 74LS90 74LS92 74LS93 74LS95 74LS96

.33 .33 .33 .33 .59 .39 .39 .39 .59 .39 .29 .39 .39 .69

1.2 5 .49

1.9 5 3.7 .29 .39 .49 .39 .49 .95

1.95 .75 .39 .25

1.39 .79 .79 .25 .25 .70 .79 .59 .79 .79 .49 .95

1.49 .95 .75 .75 .95

1.29

1.29

74LS107 74LS109 74LS112 74LS113 74LS114 74LS122 74LS123 74LS124 74LS125 74LS126 74LS132 74LS133 74LS136 74LS138 74LS139 74LS145 74LS148 74LS151 74LS154 74LS155 74LS156 74LS157 74LS158 74LS160 74LS161 74LS162 74LS163 74LS164 74LS165 74LS166 74LS168 74LS169 74LS170 74LS173 74LS174 74LS175 74LS18 1 74LS189 74LS190 74LS191 74LS192 74LS193 74LS194 74LS195 74LS196 74LS197

.59

.59

.59

.59

.49

.59

1.19

1.49

.89

.89

.79

1.19

.69

.99

.99

1.25

1.49

.79

2.49

1.49

1.49

1.49

1.49

.75

1.99

1.2 5

1.25

2.15

1.49

2.49

2.95

1.95

1.95

1.25

1.49

1.49

2.15

6.95

.99

1.95

1.95

1.95

1.49

.95

.95

1.95

74LS221 74LS240 74LS241 74LS242 74LS243 74LS244 74LS245 74LS247 74LS248 74LS249 74LS251 74LS253 74LS257 74LS258 74LS259 74LS260 74LS266 74LS273 74LS275 74LS279 74LS283 74LS289 74LS290 74LS293 74LS295 74LS298 74LS324 74LS352 74LS353 74LS365 74LS366 74LS367 74LS368 74LS373 74LS374 74LS377 74LS378 74LS379 74LS386 74LS390 74LS393 74LS395 74LS490 74LS668 74LS669 74LS670

2.95 2.95 2.49 1.95 1.95 2.95 8.95 1.19 1.19 1.69 1.79 .95 1.95 1.95 2.95 .75 1.15 1.75 4.39 .79 1.49 5.75 1.29 1.95 1.95 1.29 1.75 1.65 1.65 .95 .79 .99 .99 2.95 3.95 1.95 1.95 1.95 .59 1.95 1.95 1.95 4.95 1.69 1.89 3.55

DEALS □ DEALS □ D£/IAS

OUR BUYERS ARE IN

CONTACT WITH EVERY MAJOF;

SUPPLIER AND O.E.M.

BUY HERE AT 1000 PIECE

QUANTITY PRICES

ALL MERCHANDISE 100%

GUARANTEED! 15 DAY FULL

CASH REFUND!

JUST HOT STUFF

POWER SUPPLIES

If you can

4beat these prices

f we will be truly

amazed. OEM's

at 500 lot pay more

than this. Call or write for full spec, sheets.

DISK POWER SUPPLIES

PRIAM- SHUG ART -CENTURY- MICROPOLIS

+5V@9A |-5V@>.8A I+24V @ 7A | US-3B4

89.00

SHUGART - SIEMANS - MPI 5V

+5V @ .5A

+ 12V@.9A

US-340

33.50

+5V @ 2A

+ 12V@4A

US-323

56.25

SHUGART - SIEMANS - CDC 8"

+5V@ 1A

-5V@.5A

+24V@ 1.5A

US-205

52.50

+5V @ 2A

-5V@.5A

+24V @ 3A

US-206

69.00

+5V@3A

-5V@.6A

+24V@5A

US-162

89.00

+5V@1.7A

-5V @ 1.5A

+24V@2A

US-272

69.00

+5V @ 2A

+ 12V@.4A

-12V@.4A

US-HTAA

37.50

TELEVIDEO 912C

SOROC IQ120-$675.00 Televideo 912C- 665.00 ADDSR-25 - 710.00

Also have S20C, SOROC, HAZELTINE, etc. What we don't have is room on this page. Call Toll Free 800 number for prices.

C-ITOH PRINTER $499.00

Look closely at the

photo and see other

adds in this rag at

$995.00. Perfect units,

warranteed. Only 500 pes. Same story,

manufacturerer had too many.

S-100 CARD EXTENDER

$12.50

(Gold Contacts)

As long as there is a price war, we will fight your battle. Compare at your local Dept. store and buy U$ MICRO.

MEM0REX - VERBATUM - WABASH

BASF FLOPPIES

BOX OF 10 ONLY:

$2.65 ea

5V4"

5V."

5%"

8"

8"

8"

SOFT HARD 10 HARD 16 SOFT 1D SOFT 2D SOFT2DDS

2.65 ea. 2.65 ea. 3.25 ea. 3.85 ea. 5.00 ea.

664 N. MICHIGAN AVE. • SUITE 1010 • CHICAGO, ILLINOIS 60611

CALL TOLL FREE: 1-800-435-9357 * MONDAY thru SATURDAY

(ILLINOIS RESIDENTS CALL: 815-485-4002) • 8:00a.m. to 6:30p.m.

TERMS: Prepayment - C.O.D. up to $100.00 - M/C, Visa

Please allow personal check to clear before shipment.

WRITE FOR FULL CATALOG!

SPECIAL OF THE QUARTER SPECIALS OF THE MONTH

S1-MOD (KIT)

$189.00

Complete S-100 12 Slot Computer. Ample system power with regulated power for drives. Excellent for Subsystem or Hobby use. 4 hours to build. {6 conn, incl., less fans)

DUAL DRIVE SUBSYSTEM

$995.00

2 SHUGART 801R POWER SUPPLY

If this looks like a Lobo

DriveSystem, don't be

fooled. Just because it

looks like one, works like one, smells like one

and tastes like one (?) doesn't mean it has to

cost like one!

EXPANDABLE RAM

*SPECIAL*SPECIAL*SPECIAL*

This is the best all around 64K board you can buy. If after you see it, you don't agree return for full refund. Bank Select by extended address lines or I.O. 40H.

vijiiisitiiiiiiB

• $389.00 A&T*

S-100 POWER $79.50

Simple Brute Force!

S-100 Power Supply,

30A <s> +8V,

6A <s> +16V,

6A <s> -16V,

PC Board Design.

Jfc

Z-80 CPU (KIT)

The first time thfs

world popular CPU

offered in Kit. 2 serial,

3 parallel, CTC, EProm

Z-80 at 4 mhz. Software

buad rate, etc. (less Prom & cable)

$212.00

12 SLOT MOTHER

We have connectors and power supply too. Start your system with quality components. Terminated.

$22.50

CONNECTORS $2.50 ea.

FANS $14.95

0

m

These are brand new,

in the box fans. Not

noisey bearing pullouts.

Never again at these low prices!

3-1/8'

4-5/8"

4116s

200 IMS

Expansion 16K Dynamic RAMs for Apple, TRS-80

Intel, Call for manufacturer

$3

DIP-80 $399.00

Don't be mislead by this _

LOW price. This is a rug- —tf

ged 100% Duty Cycle ■•''

7 by 7 Dot Matrix Printer. jnM^Mi^H Brand new, factory warr. i

• RS-232 ADD $65.00 • TRACTOR FEED ADD $70.00

2114s

I One of the world's two

most popular STATIC

RAMs. Factory prime I tested units. Sold in lots of 8 only.

FUJITSU, HITACHI, etc.

$3.45

200 NS

TMS-4044 MM-5257 INTEL 2147

$4.25

250 NS

The other of the world's most popular STATIC RAMs. This one is 4K by 1 organization. Don't buy Gold, buy these, the price won't last!

2716s 2708s

$13.50 (450 NS) $6.95 (450 NS)

Remember when 2716s were $50.00 and hard to get? These units are so beautiful it's hard to part with them. But we will, for a small price. Guaranteed!

SHUGART DRIVE

8" 851R $585.00

8" 801R

Manufacturer had . ^ -^ _ -^ -^

too many, buys at $395.00

1000 piece rate,

sales dropped, so we got'em. Fantastic buy, get them while they last! Full warranty.

SIEMANS DRIVE

8" 120-8

$375.00

Very Special Price on

these BRAND NEW current production units.

Add $10.00 for Extended 1 Year Warrantee!

Circle 316 on inquiry card.

CaIiFornia DiqiTAi

Post Office Box 3097 B • Torrance, California 90503

FREE PLASTIC LIBRARY CASK INCLUDED WITi) THE PURCHASE OE EVERY BOX OF DISKETTES

CiilifomU IJi^it^l l>v one of liruiuci'i'it of magnetic uiedt itlloil double density at 40

i every box of disku'.u I p]uase specify Ctiliijiutur

MINIDISKETTES cmorex 1)401

:,-lui!im .V.THtUHlK!

MMU-CDS(DI)tlO)

rtfjulrt-'d sudors.

MB^T. box

Cue hundred boxes 321,30

T*4(0HiaXlB)

EICHT INCH

Seoieli box

10 lis. OysiW ijos 1U Iw. MUX lio.l

10 bK

Single side/single den

7-10-D $JJ3.

$33. :n.;«/i S4ti. 5-n. aouu * :

Single sldW double- i1l-i

7-11-D i.">.

-l;i. ;m*/ld 7:1 73. 30M ;i'

Single Bldelm sector

i-io-s-i :is.

Double aide/ double [)

713-1 GS.

Sil. na. 3115 4!

-15.

SCOTCH brand head c

L-aniim kit. $

24.y:j W-.IA-CK(3>(fi) please spectfv i

/-i a"

Prices available on rt

l"MI ,0,': ^"

. cariridgos. diskpneks. tfulumn tltsh

tten.

IIM0IY

r

TRS-80 &l APPLE II

16k memory (8)4116's

r

~r

-a

I installation is simple. Anyone who has ever changed a spark plug should bo abl« lo up-grade his mitii'ocomputer.

How can Ca il'uriiia Digital offer these memory up-grade suis ul 25% below our compel ition? Simple, we l)ii,y in volume, whole-sale lu dealers autl sill Die balance directly in owners ol'personal microsystems. These 16K dynamic memory circuits are factory pi'imc and uncondiUoiudly guaranteed for one full \-ear. NOW, before you uliaiige your mind, pick up the telephone- and order your up-grade memory Iron California UigiUd. Add $3 for TRS80 jumpei-s.

STATIC i-3i :3l'-9(j loo-jc -yytj ]|\t

.09 .Hb .90 . 8a

. J9

21L02 4fi0nS. 1. 19

2IL02 250nS. 1.49

LM14 IKx-l 450 .",. Of)

2114 IKwl 300 IS. 9".

4044 -IKxl 4.i0 5. Ub

4044 41 \1 250 9. 95

4045 1KX4 450 8. 95 4045 !Kx4 250 9. 95 5'257 low now. 5. 95

1. 25

. 50

4. 50

8. 50 8. 00

9.00 *

8.00 *

9. 00 *

5.00 4.80

NEW

from

Shugart

Technology

5

Megabyte Hard Disk Drive

Packaged in the same physical size, as the industry standard 5 i/4" minifloppy disk drive. The micro-Winchester stores thirty times as much data (6.38 megabytes unformatted), accesses data twice as fast (170 milliseconds) Eind transfers data twenty times faster (5.0 megabits per second. )

The ST506 is factory sealed to protect the media ironi envii'onme t al contaminates- Requires only DC voltage. Dual California Digital 5 1/-1" enclosure. ST506 drive and power supply.

Shugart Associates SA400 removable media disk drive for above package, add: S-100 tt Apple controller scheduled for spring release.

*1500 *300

^3, Shugart Associates

IBM 2980

SELECTRIC

BANK TERMINAL

*250

II1M :>l'S!U icroiin.-il wis i

Eh hank. Information entered "no tiis terminal would insiautwitauslT

usiBiiiui'B :icrJOUIlt ■" Hi" computer. A record of tbc iraitsaci ion w«lld lusted into Hit CuBtomePS passbook iuiiI siiniiliuiuoiislv recoi-di.il onto ;i com ous 4U column |wjpt*p 1-..U loci.iL'd within Hie terminal. USKU :ach Liiii is supplied with prim b;dl. ribbon and documentation. 77 lbs. SP(J-2UUu|

mmm ■& !24?s

s , _ _ g. vtll'.urv ui Kit niwLii lui niJb iez. r\ i_ i -inn

'tHf Iff . iu ke^ .Micro-Switch t.r.'Md n-fi Erh-a

"iq^jp EH~TH^MI7J ktvboai'd. (U5LU). Ten l.n 1T1.

1 LLl-P* • San,Gm,h ,,iti, ASCII »„c,k

LLFTXt

Also available Maid-!

$139.50

801/ R Disk Drive 15 lbs.

Shugari 301/il witli CP'IOB puwap SH plete in dual enclosure with all tlio V DOGUmenlation included. Mi pounds. MSI)- liSOl

wiih Iwo .Sluii!.u-t 801H -I r,Q pounds. MSD-2801 Disk drive cable. !> rei't TiO conduciur wttti edye c al boib ends. WCA-850S {23.00

isk-ii-ivfs. 230V. SO-Mlfe add SSO.OO jjt_-i

271B EPROM

SALES95

We h.ive slashed price in an effort to rodaee our over stocked inventory. These are single five volt EPROMs manufactured by or,& of (he Worlds largest producers ! of semiconductors. All are first quality prime devices. Ceramic 450 nS.

I UlTiNvViolET ProcIucts LVS11E

UV EPROM ERASER

With purchase of

FORTY

2716 EPROM's

^/V value

BSR Timer eiyht channel *f>5,.00

Master comrol console 34.95

Ultrasonic Conirollc-r UtJH

TI-81D

1495

List $1895

Iniaui wire wrap(Tli

Sullins [H-!!cl. . ••M' Sullins tlt-Kcl. WAV

Sullins/AUair . MU"

:*S/72 Diyit.il tJi-ouji s! r r,.m

.'(G/73 Di^iinl Group WAV (i.liU

JH/UC Mntnrola lilifKlS/l' G.liU

i;t/!lG Moio. CUD* \V/\i 7.lit)

B pili S.l* ?.0U $,43

M phi -ID .Bi) .!'i

10 pin .1^ .11 ,50

11! pin .'5 ,13 M

2-\ pin -2DI .'M „»<t

40 pin .-)J .-ID 1.80

IJU^.'iS ri.-in:J^ :i.j:, J.I;,

RHlliLK CABIJ-, i:i.KM!:c'i'(.n:.s it)Alt) Tll.S-au O;;, -|.i)^ '1.7

PORTABLE DATA ENTRY SYSTEM

Regulated $Q95

Power Supply

5 VOLT 5AMP

53 Sankyo Magnetic Card Transport

tl I Mil l MODULATOR

^i.

□ATA INPUT ^r-^, TERMINAL

ircd rrDin ihe CMC divLsiun ...f 'lit-- i'lT.K ritlon. The unit was uricinUlv ilcsiniicd li directly onto magnetic tape.

ici? .1 d:.t.. :mi) mIoi-Is iln.- (tju-iMtor or iiL-niling problcniB. I of nil ibis "XJSEU" u-riiiiu.d, wiib , ttule iniafitaalifln, can be ctwJttwi ii S-100 Loin|.uler jiiiI vidua display; or wi'li slti-li

i the Kockwirll AIR1-B5 "'icro/cu™puiL'

ipplv

n for

ion.d :LM). I si.-.- Jum.

WESTERN UNION

ENCLOSURE

efeiy

m

VISA

All merchandise sold by California Digital is premium grade. Shipping: First five pounds $2.00; each additional add $.40 Foreign orders 10% shipping. Excess will be refunded. California residents add 6% sales tax. COD's discouraged. Open accounts extended to state supported educational institutions and companies with a "Strong Dun.& Bradstreet. " Warehouse: 15608 Inglewood Blvd. Visitors by appointment.

-.-,'■-■ surplus In. Int I ..-v ln.XCS .supplied with Ihrei;

■•'■Jil L-duu doiint-c:TC1J^: UH25S coinmuiiLcatioiis conncclor: 1

10 1/3" ^S UK SbippinR w.-iKbl 8 lt». 3^4.77^

TOLL FREE ORDER LINE

800)421-5041

TECHNICAL & CALIFORNIA

213679-9001

CAlifoRNJA DiGITAL

Post Office Box 3097 B • Torrance. California 90503

Full 136 Characters for the price of 80

Introducing the

ANACOM ISO

DOT MATRIX PRINTER

Mfg. suggested list $1350 California Digital Introductory Price

SI

quality of Hie pr

i tin- moHu-t for ,! "C^-iulii'- LiiL'imrn ■later, pit:asu consider ihe Anacom I".1 .sine, a less reliable iiiuchme.

iA-ir.StP. Held

====== 31D1

= s-a =■=■= DISPLAY = ^="="= TERMINAL

■In., plug tomf>;iinlile micro ei.inplliei- In.lusl rv.

I'hU nioduliiflv finiBin4Bi«ii CHi-Ti.itniii.il )ma bi!i.-n triiBineetUid Kiih iIil- usei- in mind, rlic video display liitxluuK swivels Jilirl lt|ta li> provide llii.- gp-fMOl- with

L-risp 1 in- II cluiFOBlur nl.ili-ix.

lu display r.uclime siritus and aid in tilt diagnostics

with iimnei'ie piitrv p.id. Kiriit user rit-fllialiU furic

Vlic I1H1 vhlva terminal is KSL'i? compilable .mil tisplavs -.1! l:!fl ASHII characters includim; conli-ol codes

Accessible customer setup swIlclurS aid in etioasine such opilous as line (speed, pju-itv scroll. and reverse

Hui iirosi of nil. llitilt inlu evef>' U 01 le-ruiiii.-.I is ttie i|u..Hl>' tll.'H vou llllVi! l.'ari.eil in irspeel from L)|« IBM

IBM direct price 11295 CALIFORNIA DIGITAL

discount price

tllQC Immediate

lltJO deliver

. ...'..i.>.u:.j;ax£or| ,.. t ==&-*■ i

.i.li., ■ U.K.,

:: LME\A/

from INTEGRAL DATA

460

Paper Tiger

-*--- $1150

GRAPHICS

lic.illy uVerlappin[> dols. The ln:.id

| ccasor control liy a stepper molor d

Two K " buffer allocs the primer i.

tfECSpinwriter 551QP/S

JEC V-300

®Word Processing

DaisyWheel Printer

U595

.■aHonnlily priced l-.'iier (jiialliy printer.. .

:o" horizontal, 1/48" vertical.

b standard Uiablo brand tnterehangsble daisy prli

1 (Julia CPU microprocessor iront rolled. Interfax noctor. Shipping ft 8 !bB. PRV-30G.

TELETYPE MODEL 43

4320 KEYBOARD MODELS TTL serial output AAA $ US5 RS232 aerial AAK 1050

Friction 80 column AAE 1100 Friction 80 RS232 AAL 1195 Hell 103 Modem AAB 1495

rr^n

a EPSON

MX-80 *495

llle 11X-H0 l:

ajier. Requires "fight

.11.1 interfacine.. PHK-.UMHI

CEnTRDniC5

730 $595 737 $750

Uoih tin.- Centronics 730 and the 737 are capable of ace. standard office letterhead or pin feed continuous Forms. tor higher rcsoluiion the 737 implements a nine wire d< f. .TiX print lie.id. Parallel interfacing. Add $65 for RS232. PitC-7'JOI* IS). PRC-737P <S) 17 lbs.

VISA

HEWLETT PACKARD

2650

HPS5

(.-lull Packard ilP-8.i is a co low cos' portable computer . I his self contained packn ■; I'i't , keyboard, printer.

AMPEX

DIALOGUE 80 CRT TERMINAL

J995

New from the Ampex Corporaili.il. The Minlu^te BU features removable keyboard, dlsplayable two paces (fuiir i ipi innal) ilual |i■'t)|.;i~rnJi keys, half intensity protected

fields and status line. Transmits data either block, line or character mode. Excellent value. VDT-EJ80 shipping J7 lbs.

Appled Qgtal Data Systems Ire

in ■<; i:\ I 3D

special function i ti'.pliies. :; iih

nini. virr-uao

BMC

VIDEO MONITOR

s259

-hosphor with in MH« band

jfiii video input make the BMC monliur for anvtaie i-eu.ii i rint;

direct connect

Your Choice

MODEM $169

11k. Universal Uala Svsien s 1031.1' is s.vi.eli selectable bMwecii answ.'r.«»! orie Inntu mod.-s. lullv Hell IQ.'I cumpatalile. IHrti-lly eoiniecls lo Hie neiv nui.lnlaitelephone jack. 100«i poaeiid I ,ri>in the telephone line. Xo need lo loenie iiiudeni i |!f.iM!: uv to A.C.NO- ei- I'LcepHcle. lid l)-10:ll .1' '£ pounds.

Nov.,lion "l)"Cat connects to nmsl of Ike new "Bell" .i.o.lular rtamJSKtS. Ideal for

All merchandise sold .by California Digital is premium grade. Shipping: First five pounds $2.00; each additional add $.40 Foreign orders 10% shipping. Excess will be refunded. California residents add 6% sales tax. COD's discouraged. Open accounts extended to state supported educational institutions and companies with a "Strong Dun & Bradstreet. " Warehouse: 15608 Ihglewood Blvd. Visitors by appointment.

ACCESSORIES FOR THE

COMPUTER

CALIFORNIA COM

irfac

5 Inlcrfai

1 2K PltOiM Modul Calender/Clock. B;il. Iinck-U Parallel interface 772Q.-\ Programme Tinier 1T-I0A Analofi/Dicilal convener 7 11

U.C. HAYES PRODUCTS Micro mot lorn for Apple COMPUTE]) STOP PHOULiClS Double Vision / U0 Column Video

INTERACTIVE STRUCTURES 1C Channel A/D card AlO/st

tlOL'.\TACv CO.MPUTEit PKODUCTS Jitro X-10 sys-.em for USH $231

iiiro X-10 cardoiJv 10?

5SM MICROCOMPUTER

Uuid serial parallel interface A

SOI1HENTO VALLfJY ASSCXIIAI

S-IOO BOARDS

Assembled • Tested • Burned in

MEASLillt.Mt^r SYSTEM Dynamic memory DMU-6! Dynamic memory D1II1 -3:i GODHOUT/COMPUPHO llual B0BB/B08J 16 hit CPU 2-80 CPU 11 bil address -1 Mil Static RAM32K (Alpha Itlicro)

SEATTLE computilH PRODUCT

B0I1G IB bil CPU 2 eaial set/itLi tins CALIPOHN1/1 COMPUTh.;U SYSTKP S-10U Mainframe 2200A

CALIICHMA DATA COHI'I'IIATION

rrupt com'l 3P/3S

511 SALES

MUM.1CR PRODUCTS

E«temlcr lioai-r^Lofilf pro Relay •SJlo/comrol board 13. C. HAYES PRODUCTS Mleromodem S-10D ICC ARTEC ELECTHOMC5

IIOBfi CPU

TELETEK

SINGLE BOARD COMPUTER FLOPPY DISK CONTROLLER

-;t:i_'l<

bd)

and two parallel ports add lo lltC fleXihiiiiy of this single board c-utnpuier. CX'her standard features ire realtime clock, reset jump to monitor, voetorei interrupts and potvnttal lor eomrollini With the addition of an uxlenial 2a volt j.o1 board becomes cap all ti? <>( pt-.-iiramiiif -'Tl

S-100 Mother Board $35

Quiet Boss

8803-18 18 slot IMSAI

TOLL FREE ORDER LINE

(800)421-5041

TECHNICAL & CALIFORNIA

(213)679-9001

Circle 317 on Inquiry card.

3'x HEADQUARTERS

2114-3L

5257-3L

2708

2716

4096 BIT (1024x4) 300ns

(TMS 4044)

450ns 8K

450ns 5 Volt only

LOW POWER STATIC RAM

4096x1 300ns LOW POWER STATIC RAM

EPROM

16 K EPROM

8/332oo

8/s5000

s850 each

s1195 each

100 + s300

100 pes. + s475

or 8/s5400

or 10/s9000

MODEM SALE $129.00

THE STAR

MODEM

from LIVERMORE

FEATURE

FITS GTE HANDSETS!

2 YEAR WARRANTY

EXCLUSIVE ACOUSTIC CHAMBERS

The exclusive triple seal of Livermores new flat mounted cups locks the handset into the acoustic chamber yielding superior acoustic isolation and mechanical cushioning. Designed to adapt to most common handsets used throughout the world, the STAR offers the utrnost in flex ibility and transmission reliability.

Specifications:

■ Data Rate: 0 to 300 baud

■ Compatibility: Bell 103 and 113; CCITT

• Frequency Stability: ±0.3 percent. Crystal controlled

• Receiver Sensitivity: -50 dBm ON, —53 dBm OFF

• Modulation: Frequency shift keyed (FSK)

■ Carrier Detect Delay: 1.2 seconds ON; 120 msec OFF

• E1A Terminal Interface: Compatible with RS 232 specifications

• Teletype Interface: 20 milliampere current loop

• Optional Interfaces: IEEE 488; TTL; TTY 43

• International (CCITT) frequencies available

• Switches: Originate/Oft/Answer; Full Duplex/Test/Half Duplex

■ Indicators: Transmit Data, Receive Data, Carrier Ready. Test

• Power: Supplied by 24 VAC/150 MA ULVCSA listed wallmount transformer. Input 115 VAC, 2.5 watts. (A 220 VAC, 50 Hz adaptor is available upon request.)

• Dimensions: 10" x 4" x 2"

• Weight: 1.74 lbs. (3 lbs. shipping weight including AC adaptor.)

• Warranty: Two years on parts and labor, excluding the AC adaptor which carries the manufacturers warranty

List

SALE

1 Part No.

Description

Price

PRICE

LIV-STAR

RS232, TTL Modem

$199.00 $129.00

LIV-STAR20M

RS232, 20MA Current Loop $199.00

512900

LIV-STAR-VZ1

CCITTEuropeanStandard $229.00

.20900

LIV-IEEE

IEEE 488 Standard

$395.00

[249.00

LIV-IEEE-V21

IEEE 48B. CCITT Standard V $465.00 $388.00

CABLES

m

[

Pact No.

Description

<^

^

Price

■ CND-RS2328F RS232 8 Cond 8 ft...

i

^

.$19.95

I LIV-I2I IEEE to IEEE 2 Meter

}

$59.95

1 LIV-I2PETIEEE to Pet 2 Meter

$59.95

RS232 and "D" SUB-MINIATURr

rnNNPr.TDi

,s r

^WffiWJVi'i^

WWW—/

/ **'—

Wft^t

^T

>■*

P = Plug. Male Type - S = Socket. Female Type

C = Cover. Hood

PAR

NO.

DESCRIPTION

PRICE

19

1D-24

2599

CNQ

DE9P

9 PIN MALE

S 2.10

S 1.90

$ 1.70

CND

DE9S

9 PIN FEMALE

S 2.70

S 2.40

$ 2.10

CND

DE9C

9 PIN COVER

S 1.50

S 1.25

$ l .10

CND

DA15P

15 PIN MALE

$ 2.75

S 2.45

$ 2.15

CND

DA15S

15 PIN FEMALE

$ 3.95

S 3.60

$ 3.20

1 CND

DA15C

15 PIN COVER

S 1.50

S 1.30

$ 1.10

1 CND

DB25P

25 PIN MALE

S 3.5D

S 3.25

$ 3.00

1 CND

DB2SS

25 PIN FEMALE

S 4.60

S 4.35

$ 4.20

1 CND

0851212

1 PC. GREY HOOD

S 1.60

S 1.45

S 1.30

1 CND

P25H

2 PC. GREY HOOD

S 1.50

S 1.25

$ 1.10

1 CND

DB51226

2 PC. BLACK HOOD

S 1.90

S 1.65

$ 1.45

1 CND

DC37P

37 PIN MALE

S 5.80

S 5.10

$ 4.45

1 CND

DC37S

37 PIN FEMALE

$ B.70

$ 7.70

$ 6.70

1 CND

DC37C

37 PIN COVER

$ 1.80

$ 1.55

S 1.30

1 CND

DD5DP

50 PIN MALE

S B.75

J 7.75

$ 6.70

1 CND

JD5DS

50 PIN FEMALE

$11.65

$10.25

$ B.90

1 CND

DDSDC

50 PIN COVER

$ 2.00

S 1.B0

$ 1.60

1 CND

020418

HARDWARE SET 2 PR. RK?3? ORWP FIA

S 1.00

$ O.BO

$ 0.7D

1 CND

RS232BF CLAS<

$19.95

$17.95

$15.95

CENT 700 SERIES

| CND

5730360

PRINTER CONNECTOR

$ 9.00

$ 7.50

$ 6.00

S^£

Static S-100 Memory

32K ECONORAM XX

List Price

GBT164A16 16K RAM AST $399.00

GBT164A24 24K RAM AST $539.00

GBT164A32 32K RAM AST $699.00

16K ECONORAM XIV

$329.00 $455.00 $569.00

GBT143U GBT143A

Unkil A&T

List Price Our Price

$279.00

$349.00 $299.00

SPECTRUM S-100COLORGRAPHICS BOARD

GBT144U UNKIT GBT144A A&T

List Price Our Price

$299.00

$399.00 $349.00

GBT2D SUBLOGIC UNIVERSAL GRAPHICS

INTERPRETER SOFTWARE $35.00

8085/8088 CPU BOARDS Board with 8085 only

List Price Our Price

GBT161U Unkit $235.00

GBT161A Assembled & Tested $325.00 $305.00

BOARD WITH 8085 & 8088

GBT1612U Unkit $295.00

GBT1612A Assem. & Tested $425.00 $399.00

I/O BOARDS INTERFACER I 2 SERIAL I/O

GBT133U GBT133A

LIST PRICE

Unkit AST

$249.00

INTERFACER II 3 PARALLEL 1 SERIAL

OUR

PRICE

$ 199.00

$219.00

GBT150U UNKIT GBT150A AST

$249.00

$199.00 $219.00

SAVE $239

00

ECONORAM XA 32K RAM

Order No. GBT129A32

■ 4MHz withZ80 5 MHz with 8085 Assembled and Tested S-100 Compatible Fully Static 24 Bit Extended Addressing

Reg. $689.00

Sale Priced

$450.00

TRS-80/APPLE

MEMORY EXPANSION KITS 4116's RAMS

q* from Leading manufacturers (j>

/^(16Kx1 200/250ns) %%

8fors2900

ADD $3.00 FOR PROGRAMMING JUMPERS FOR TRS-80 KEYBOARD

4116's 100 pes & UP $3.00 each 1000 pes & UP $2.75 each

MAINFRAMES

From the power supply through the sturdy chassis, TEI constructs and assembles each mainframe with great care. Every TEI mainframe utilizes a constant voltage transformer (CVT) which delivers clean, regulated power at the proper level, reducing the heat in the computer cards. The output voltage on the transformer remains, nearly even with the input voltage varying from approximately 85V to 140V. This means the mainframe will never notice voltage variations or even a brownout. It also provides 100 dB noise rejection to protect the computer from voltage spikes and line noise.

S-100 MAINFRAMES

TEI-MCS112 12 Slot Desk TEI-MCS 122 22 Slot Desk TEI-RM12 12SlotRackmount

TE1-RM22 22SlotRackmount

Shipping Weight: On 12 Slot Mainframes On 22 Slot Mainframes

DUAL 8" DISK CABINETS TEIDFDO Desk Cabinet $675.00 $599.00

TEIRFDO Rack Mount 820.00 749.00

Include Money for Shipping on all Mainframes

s.ioo@®^%>

MOTHERBOARDS ^

LIST

OUR

PRICE

PRICE

$685.00

S615.00

SB45.D0

S760.00

S800.00

$720.00

S945.00

$850.00

35 Lbs

50 Lbs

GBT-153U GBT-153A GBT-154U GBT-154A GBT-155U GBT-155A

UNKIT 6 SLOT A&T 6 SLOT UNKIT 12 SLOT A&T 12 SLOT UNKIT 20 SLOT A&T 20 SLOT

LIST PRICE

$129.00

$214.00

CCS-2810 Z80 CPU 2/4 MHZ CPU W/Serial I/O

CCS-2810 A&T

J_

PRIORITY ONE ELECTRONICS

16723 B ROSCOE BLVD. • SEPULVEDA, CA. 91343

Terms: Visa. MC, BAC. Check, Money Order, U.S. Funds Only. CA residents add 6% sales tax, Minimum order $15.00 Prepaid U.S. orders less than $75.00 include 5% shipping and handling. MINIMUM $2.50. Excess refunded. Just in case ... please include your Dhone no. Prices subject to change without notice. We will do our best to maintain prices thru February 1981 •SOCKET and CONNECTOR prices based on GOLD, not exceeding $700 per oz.

'Sale Prices are for prepaid orders only credit card orders will be charged appropriate freight

OUR PRICE $ 89.00 $119.00 $129.00 $149.00 $174.00 $189.00

DISK DRIVES, etc.

^.Shugart

SA801R SAL

SHU-SA801R 2 OR

MORE

Capacity

Unlor matted

Per Disk

Per Track IBM Format

Per Disk

Per Track Transfer Rate Latency (average) Access Time

Track to Track

Average

Setting Time Head Load Time

395

Single Density

3.2 megabits 41.7 kilobits

2.0 megabits 26.6 kilobits 250 kilobits/sec. 83 ms

8 ms

260 ms

8 ms

35 ms

$41 Oc

00

ea.

Double Density

6.4 megabits 83.4 kilobits

n/a n/a 500 kiiobils/sec. 83 ms

8 ms

260 ms

8 ms

35 ms

CSM

"^ *>««*** California Computer Systems _J CCS2422A FLOPPY DISK CONTROLLER ,.„,..,.- __ WITH CP/M VERSION 2.2 $375.00

LIST $400.00

SALE

IEEE S-100 CAMPATABLE SINGLE/DOUBLE DENSITY 5VV78" DISK DRIVES SINGLE/DOUBLE HEADED ASSEMBLED & TESTED

^ferbatim

Sectoring

Application

Box of 10

VRB-MD 525-01 VRB-MD 525-10 VRB-MD 525-16 VRB-MD 577-01 VRB-MD 577-16 VRB-FD32-1000 VRB-FD34-1000

Soft Sector Hard 10 Sector Hard 16 Sector Soil Sector Hard 16 Sector Hard Sector Soft Sector

TRS-80 Apple North Star Micropolis 77 Track Cert 77 Track Cert Shugarl 801R IBM 3740

S29.95 $29.95 S29.95 S4B.D0 S48.D0 S37.00 S37.00

MICROPOLIS

Thinker Tbys

r*y m J»|*

MICROPOLIS OVERSTOCK LIST

DESCRIPTION LIST

S-100 SUB-SYSTEMS

MCP-1053-4 MCP-1053-2 MCP-1043-2 MCP-1041-2 MCP-1042-1 MCP-1041-1

1.2MB2HEADDUAL

630 KB DUAL

315 KB SINGLE

315 KB SINGLE. NO PS

143 KB SINGLE

143-KB SINGLE. NO PS

$2605.00 $1895.00 $1145.00 $1045.00 $795.00 $695.00

SALE PRICE

S1395.D0 S995.00 S695.0D $639.00 S625.00 S595.00

COMPLETE W/S 100 CONTROLLER. CABLES. MANUALS AND MICROPOLIS MDOS AND BASIC

ADD-ON DRIVES

MCP-1033-2 MCP-1023-2 MCP-1021-2 MCP-1022-1 MCP-1021-1

630 KB DUAL

315 KB SINGLE

315 KB SINGLE. NO PS

143 KB SINGLE

143 KB SINGLE. NO PS

$139500 $645.00 $545.00 $545.00 $445 00

S895.00 495.00 S475.00 5375.00 S360.00

REQUIRES ACCESSORY ADD-ON CABLES

MCP-1027-1 MCP-1037-1 MCP-1027-2 MCP-1037-2

TRS-80® DISK DRIVES

35 TRACK SINGLE $545.00 S299.95

35 TRACK DUAL $1195.00 S695.00

77 TRACK SINGLE $645.00 S439.00

77 TRACK DUAL $1395.00 S795.00

ACCESSORIES

APP 395M NEW DOS/80 TRS-80"

35 thru 77 TRACK OPERATING SYSTEM

PR1-34CEEE-2 Two Drive Data Cable PR1-34CEEE-4 Four Drive Data Cable

SUPPLIED ON

35 TRACK 77 TRACK $149.00 S159.00

$29 95

Thinker Tbys

DISCUS M10

10MB 8" HARD DISK DRIVE

&S100 CONTROLLER

WITH CP/M 2.2

Capacity

Unformatted Formatted Track Capacity Cylinder Capacity

Recording Characteristics Recording Surfaces Heads per Surface Usable Tracks perSurface Track Density (per inch)

THTM10S 10MB 8"

11.7 megabytes 10.0 megabytes

12,000 bytes 48,000 bytes

4

1

244

195

LIST SALE

PRICE PRICE

$3695.00 $2995.00

&

PRIORITY ONE ELECTRONICS

16723 B ROSCOE BLVD. • SEPULVEDA, CA. 91343 Terms: Visa. MC. BAC. Check. Money Order. U.S. Funds Only. CA residents add 6% sales tax

Minimum order $15.00 Prepaid U.S. orders less than $75.00 include 5% shipping and handling MINIMUM $2.50. Excess refunded. Just in case ... please include your phone no. Prices subject to change without notice. We will do our best to maintain prices thru February 1981. ■SOCKET and CONNECTOR prices based on GOLD, not exceeding $700 per oz.

'Sale Prices are (or prepaid orders only credit card orders will be charged appropriate freight

^

DISCUS/2D™ DOUBLE DENSITY DISK SYSTEM

Why not go all the way to the professional/industrial standard of 600K byte/side disk memory with your S-100 system? The new DISCUS/2DIM full-size, double-density floppy disk system is actually less expensive than many mini-floppy systems.

And Thinker Toys'" hasn't just made full-size, doubledensity disk memory affordable.. .we've made it more functional.

Thinker Toys'" has developed BASIC-VI" a virtual disk BASIC that lets you address all 600K bytes(expandableto 1 megabyte) as if were main memory. The data format is soft-sectored and compatible with IBM's new System 34. And DISCUS/2D,M accepts both single-density and double-density disks for complete flexibility in data storage.

And DISCUS/2D'M is even more attractive because it's priced and delivered as a truly complete system. It's complete with all hardware. It's complete with all necessary software. And it's completely assembled, tested and warranted.

Specifications: •CP/M V2.2 standard

• Plug compatible withShugart, Remex and Siemens single- or double-sided drives

• Double/single-density capability utilizing MFM and FM data formats

■ Western Digital 1791 LSI floppy disk controller chip

• Uses 2K of S-100 address space:

-1 K PROM with built-in disk drive and I/O utility subroutines incorporating memory mapped I/O

— 1K 2114-3L 300 ns access time RAM for disk data offering and general purpose use

• Starting address of memory space is 340:000 (E000 hex) for compatibilitywith other popular ROM based systems

■ Phase-locked data separator and crystal controlled disk data write precompensation capability to insure the highest standards of data integrity in double density mode.

• Compatible with all 2 MHz and 4 MHz systems which conform with the proposed IEEE standard for the S-100 bus

• 1602 UART with crystal-controlled baud-rate generator

• Sixteen switch selectable baud rates from 50 to 19,200 bits/second

■ TTY current loop and industry standard RS232C serial interface

• Power-on jump circuitry for automatic bootstrap loading from the disk drive

■Powersupply requirements: + 8V@1200 ma; + 16V@ 150 ma; -16V @ 70ma. uS( Price SALE

THT-02DS Single Drive. $1199.00 $ 998.00

THT-0200 Double Drive $1994.00 $1649.00

THT-022S Single Drive $1545.00 S1298.00

THT-0220 Double Drive $2740.00 S2295.00

DISCUS 1 ^-v

FULL-SIZE, SINGLE-DENSITY ( ]

DISK MEMORY SYSTEM \f/

Specifications: Z

Data Specifications and Formats

■250,000 byte capacity per standard 8" floppydiskette

- Sofl-sectored IBM-compalible format: 77 tracks/26 sectors pertrack/128 bytes per sector

• Includes Disk/ATE'* disk operating system with integral monitor, assembler and text editor & BASIC-V advanced virtual disk BASIC capable of addressing up to 1 megabyte

• Software customized for SOL and Exidy available

• Patches for CP/M" included

• Optional CP/M* Microsoft BASIC, and FORTRAN available. List Price Our Price

THT-D1S Single Drive $995.00 S950.00

THT-D1D Dual Drive S1790.00 S1595.00

DISCUS HD 26 MEGABYTES List Price SALE

THT-M26S Subsystem $4995.00 S4095.D0

THT-M26A Add-on hard disk drive $4995.00 S3995.00

THT-M26HDC Hard disk controller S 695.00

Shipping Weight: THT-M26S&A 50 lbs.

Shipping Weight: THT-M26HDC 3 lbs.

ORDER TOLL FREE 1-800-423-5633 ORDER TOLL FREE 1-800-423-5633

Circle 318 on inquiry card.

TEST EQUIPMENT

<g*>HITACHI

>t7 Hitachi Denshi. Ltd.

Single and dual trace, 15 thru 100 MHz. All high sensitivity Hitachi oscilloscopes are built to demanding Hitachi quality standards and are backed by a 2-year warranty. They're able to measure signals as low as 1mV/division (with X5 vertical magnifier). It's a specification you won't find on any other 15 or 30 MHz scopes. Plus: Z-axis modulation, trace rotation, front panel X-Y operation for all scope models, and X10 sweep magnification. And, 30 thru 100 MHz oscilloscopes offer internal signal delay lines For ease of operation, functionally-related controls are grouped into three blocks on the color coded front panel. Now here's the clincher: For what you'd expect to pay more, you actually pay less. Check our scopes before you decide. All scopes complete with probes.

Hitachi...The measure of quality. HITV302B

List $995.00 SALE $859.00

■ TV sync-separater circuit High-sensivity 1mV/div (5MH2)

Sweep-time magnifier (10 times) Z-axis input (intensity modulation) Signal delay line Complete will) 2 probes CHI, CH2, DUAL, ADD, DIFF. Vertical Deflection Modes X-Y operation Trace Rotation

HITV152B DUAL TRACE 15MHZ (no delay) LIST $735.00 SALE $650.00

30MHZ

DUAL TRACE

OSCILLOSCOPE

#..i-'4-i4

HIT-V202

20MHz DUAL TRACE

LIST PRICE: $850

OUR PRICE: S798.00

■ Dynamic range 8 div.

■ TV sync-separator circuit > Built-in signal delay line

(V-352)

' X-Y operalion

1 Sweep-time magnilier (10 times)

' Trace rotation system

1 Fine-adjusting, click-positioning (unction

HITV550B DUAL TRACE 50MHZ VARIABLE DELAYED SWEEP $1745.00

HITV1050 DUAL TRACE 100MHZ

VARIABLE DELAYED SWEEP $2390.00

FOR DETAILED INFORMATION SEE OUR

60 PAGE DETACHABLE CATALOG IN NOV. BYTE

HIT-V352

35MHz DUAL TRACE WITH DELAY

LIST PRICE: $1150.00

OUR PRICE: S998.00

Economically priced dual trace oscilloscope Square CRT wilh internal graticule (illuminated scale) High-accuracy voltage axis & time axis set at± 3% (certified at 10° to 35°C) High-sensitivity ImV/div. Low drift 2 Year Warranty

[FLU K El

®

LOW COST

MODEL |\mfmf)£

D804A: 4# 1*11*1 9

Nine functions:

dc voltage

ac voltage

dc current

ac current

resistance

diode test

conductance (1-R) b. logic level and

continuity detect 9. temperature (K-type thermocouple)

• Peak hold on voltage and current functions

• Selectable audible indicator for continuity or level detection

■ 3V;-digit resolution

• 0.1% basic accuracy

• LCD display

■ Overload protection

• Safety designed test leads

FLU-D800A <fu

FLU-D802A (Funct 17, s17900

FLU-D804A Fimrt.^ s22900

FLU-D81 0 (RMS Bench 10A). . . .S259°°

FLU-D81 1 (RMS Bench w/Batt). . .299 FOR ACCESSORIES, SEE OUR 60 PAGE DETACHABLE CATALOG IN THE NOV. BYTE

— GSC-2001 FUNCTION GENERATOR —

• Sine, Square, Triangle • Separate TTL Output ■ 1HZ to .1 MHz* Vari-DC Offset • 100:1 Sweep ( ± 10V Input)

• High, Low Level 600 ohms Vari-Outputs.

list $186.00 SALE $165.00

w GSC . 4001 DIGITAL PULSE GENERATOR •>

■ Complement Output Pulse, Square Wave ■ Symetrical Square Wave • Variable Output 0.1 to 10V® 50 ohms. • Drives 40 TTL Loads ■ Pulse Width, Spacing independently variable • Four Modes-Run, Triggered, Gated, One-Shot • Sync-Out Leads Main Output LIST $235.00 SALE $210.00

_ GSC-6001 FREQUENCY COUNTER __

• 5Hz to 650MHz- 10MHz Crystal Oven timebase • External time base input • Selectable 0.1,1.0, 10 Sec. gate ■ Switchable low pass 50 KHz Filer • True TTL Compatibility at input. ,_ . _ _ -.___ __

list $425 oo SALE $375.00

PRIORITY ONE ELECTRONICS

16723 B ROSCOE BLVD. • SEPULVEDA, CA. 91343

Terms: Visa, MC, BAC, Check, Money Order, U.S. Funds Only. CA residents add 6% sales tax Minimum order $15.00 Prepaid U.S. orders less than $75.00 include 5% shipping and handling MINIMUM $2.50. Excess refunded. Just in case ... please include your phone no. Prices subject to change without notice. We will do our best to maintain prices thru February 1981. •SOCKET and CONNECTOR prices based on GOLD, not exceeding $700 per oz.

"Sale Prices are for prepaid orders only credit card orders will be charged appropriate freight

Global Specialties Corporation

formerly Continental Specialties Corporation

LP-1 LOGIC PROBE-Hand-held logic probe provides instant reading of logic levels for TTL. DTL, HTL or CMOS. Input Impedance: 100,000 Ohms. Min. Detectable Pulse: 50 ns. Max. Input Signal (Frequency): 10 MHz. Pulse Detector (LED): High speed train or single event. Pulse Memory: Pulse or level transition detected and

stored. GSCLP1 LIST PRICE $50.00 SALE $45.00

LP-2 LOGIC PROBE-Economy version of Model LP-1, Safer than a voltmeter. More accurate than a scope. Input Impedance: 300,000 Ohms. Min. Detectable Pulse: 300 ns. Max. Input Signal (Frequency): 1.5 MHz. Pulse Detector (LED): High speed train or single event. Pulse Memory: none. GSCLP2 _ Art_ nn

LIST PRICE $28.00 SALE $25.00 GSLP3—High speed logic probe. Captures pulses as short as 10 ns. Input Impedance: 500,000 Ohms. Minimum Detectable Pulse: 6 ns. Max. Input Signal (Frequency): 60 MHz. Pulse Detector (LED): High speed train or single event. Pulse Memory: Pulse or level transition detected and stored, GSCLP3

LIST PRICE $77.00 SALE $69.00

GSC DIGITAL PULSER

The ultimate in speed and ease of operation. Simply connect clip leads lo positive and negative power, then touch DP-1's probe to a circuit node; automatic polarity sensor detects circuit's high or low condition. Depress the pushbutton and trigger an opposite polarity pulse into the circuit. Fast, troubleshooting includes injecting signals at key points in TTL, DTL, CMOS or other popular circuits. Test with single pulse or 100 pulses per second via built-in dual control pushbutton button selects single shot or continuous modes. LED indicator monitors operating modes by flashing once for single pulse or continuously for a pulse train. Completely automatic, probe-size lab/field pulse generator for any family of digital circuits, Output: Tristate. Polarity: Pulse-sensing auto-polarity. Sync and Source: 100 mA. Pulse Train: 100 pps. LED Indicator: Flashes for single pulse, stavs lit for pulse train.

GSCDPI ...$B3.oo SALE $75.00

Trace signals through all types of digital circuits. Unit clips over any DIP IC up to 16 pins. Each of its 16 contacts connects to a single-bit level detector that drives a highintensity, numbered LED readout activated when the appliedvoltageexceedsa fixed 2 V threshold. Logic "1" turns LED on; logic "0" keeps LED off. A power-seeking gate networks automatically locates supply leads and feeds them to the LM-1's internal circuitry. Saves minutes, even hours in design troubleshooting, debugging of equipment. Voltage Threshold: 2 V ±0.2 V. Input Impedance: 100,000 Ohms. Input Voltage Range: 4-15 V max. across any two or more inputs. Current Drain: 200 mA at 10 V. Size: 4" I x 2" w. x 1.75" d. when open. Weight: 3 ozs.

GSCLMI seo.ooSALE $54.00

GSC LOGICAL ANALYSIS KITS

GSC Model LTC-1 Logical Analysis Kit—Complete with LP-1 logic Probe, DP-1 Logic Pulser, LM-1 Logic Monitor, wiring accessories, manuals and molded case. . $220.00

SALE S189.00

GSC Model LTC-2 Logical Analysis Kit—For high-speed and memory analysis. Same as Model LTC-1, except substitutes LP-3 High-Speed Logic Probe S250.00

SALE $215.00

ORDER TOLL FREE (800) 423 5633

MICROPOLIS" PRICE BREAKTHROUGH

=E TRS-80ADD

ON 51/4" DISK

FROM MICROPOLIS THE WORLDS LARGEST

MANUFACTURER OF HIGH DENSITY 51A"

FLOPPY DISK DRIVES

Now at an incredibly low price, you "can"add the Micropolis MCP1027M1 floppy disk drive to your TRS-80' computer. The MCP1027M1 in fully plug compalable wilh the TRS-80* expansion interface floppy disk output.

SIMPLE INSTALLATION

Simply plug the MCP1027M1 inlo your data cable, and your on-line. There is no need to worry about format compatability. Your TRS-80* 35 track 5V«" floppy disk programs will operate identically on the MCP1027M1. Compatability doesn't end here. Micropolis has even matched the colors of the MCP1027M1 to theTRS-80".

WHAT'S A LITTLE TECHNICAL

SUPERIORITY AMONG

FRIENDS?

Anyone can cut price by cutting out capacity or valuable features. But there's no long term advantage in it. Not for the user. Or the builder.

Micropolis takes a better approach, even though it's harder, using advanced design to provide more capability while also lowering cost.

For example, most 51/j-inch floppy disks cut costs by using a cheap, less accurate plastic cam or cam follower to position the read/write head. Most 8-inch floppy disks use a better approach, with a rolled steel lead screw for this function.

We go them one betterand use an all-steel system, with a precision-ground steel lead screw and steel follower. It costs more but gives us greater storage capacity with lower cost per thousand bytes. Not so incidentally, our steel construction (compared to plastic) significantly increases reliability, too. There's even a built-in File Protect feature that prevents accidental loss of valuable data. (A file protected diskette cannot be written on.)

Heat can cause numerous read and write errors that can become hazardous to your data. The major heat producing power supply components are mounted to alarge heat sink, external to thecabinet, by the power switch and fuse (located at the rear of the cabinet). This design is to assure that the drive components are kept as cool as possible to assure reliable data recovery.

MICROPOLIS BUILDS 'EM RIGHT

Reliability just can't happen, and it can't be pasted on latter. Micropolis knew you had to have it, so they designed it in. Micropolis builds it in every day. Just because Micropolis drives are economical doesn't mean they're cheap.

To save unnecessary wear and tear on the diskette, Micropolis included an automatic deselection feature which relieves head pressure on the recording surface when the disk isn't in use. This produces longer operating life: more than 10° passes on one track.

When unloading, the diskette is ejected automatically. Just pull it out.

To cap it all, disk speed is independent of any fluctuation in line frequency.

It all adds up to solid operation, year after year.

The Heart of your Micropolis TRS-80* add on drive.

EXPERIENCE

How can Micropolis offer so much for so little? No need to visit the oracle at Delphi. The Micropolis secret is simple. Micropolis is the only disk system builder who is completely integrated in manufacturing. Drawing on the experience gained in producing over 100,000 units; Micropolis is able to design and build a drive of superior performance.

This total integration means Micropolis controls everything from beginning to end. The result is a better drive for you, backed by a full 120 day factory guarantee.

YOU'RE IN GOOD COMPANY

As an individual, you can't help but wonder when you spend your hard earned money. Have you made the proper choice? With so many drives in the marketplace, and so few hard facts available to the individual, how can you make an intelligent decision? One way is to see which drives the large system manufactures and OEM's rely on. Companies like Commondore, Exidy, Harris, and Vector Graphics depend on Micropolis for years of reliable performance. That is one reason why International Computers Ltd., has recently signed a $20 million dollar contract for Micropolis disk drives. Years from now, you can look back and know you made the best choice: MICROPOLIS.

Disk drives being assembled for delivery to Priority 1 Electronics

INCREDIBLE PURCHASING POWER

Priority One Electronics, the worlds largest stocking distributor of Micropolis disc drives was able to negotiate a special price for the MCP1027M1 when we committed to buy an entire production run. The MCP1027M1 is a good buy at the list price of $545.00. The MCP1027M1 is an excellent buy at our sale price

$279.00

Now all that remains is for you to take advantage of this truly incredible buy, while the supply lasts. Credit card buyer call toll free

(800) 423-5633 except

CAAK HI call (213) 894-8171

or if you prefer use the coupon below.

*TRS-80 is a registered TM of Tandy Corp. u

(800)423-5633 (213)894-8171

Priority One Electronics

V»2 16723 Roscoe Blvd. • Sepulveda, CA 91343

Please send me the following items:

MCP1027-1 Micropolis TRS-80™ Ad on drive $279.00*

APP395 New DOS 80 operating system $149.00

VRBMD52501 Box of 10 Verbatim diskettes $ 29.95

MMM744-0 Box of 10 Scotch diskettes $ 39.95

VRBFD05 Head Cleaning Kit $ 29.95

PR134CEEE-2 2 drive data cable $ 29.95

PR134CEEE-4 4 drive data cable $ 39.95

n lhaveenclosed acheck ormoneyorder Sub

(6% C A only) Tax

Bill my □ VISA, D MASTERCHARGE Shipping $2.50

CreditCard# TOTAL

Exp. Date ■ Signature

Name

Address

City State Zip

'These sale prices are for PREPAID U.S. orders only. Credit card orders will be charged appropriate freight. On

approval, purchase orders for the MCP1027-1 will be accepted at $379.00, FOB Sepulveda, CA.

BY8101 Good thru Feb. 81

Circle 319 on inquiry card.

Best Price and Delivery

SUPERBRAIN by Intertec

'''.-■''

Self contained computer wilh dual disks and two RS232C pons Complete with CP M 2 2 and BASIC 60C0C

32K Double Density. List $2995 . YtDOO

64K Doublfi Density, List $3345 $2883

6<JK MimrVncroMart upgraded to Quart Density . . SPECIAL $3395

VIDEO TERMINALS

A/£W EMULATOR (Intertec). List $895$749 NEW INTERTUBE IIIList $895 , ONLY $749 SOROC 120. List $995 SPECIAL $ 729

IQ140, List $1495 SPECIAL $1149

PERKIN-ELMER 550. List $997 $ 799

with anti glare screen, $1027 $ 829

HAZELTINE 1410, List $900 $ 749

1420 $ 849

1500, List $1225 $ 879

1510, List $1395 $1089

1520, List $1650 $1389

ADDS R-20. List $995 $ 945

LEAR SIEGLER ADM3A, Assembled $ 849

TELEVIDEO 912C, List $950 . . Call for

920C, List $1030 prices

PRINTERS

ANADEX DP 8000 $ 849

DP-9500, List $1650 $1399

DP-9501. List $1650 JI399

PAPER TIGER IDS-440, List $995 $695

w graphics op., incl. buffer, $1195 . . $879

NEW IDS PAPERTIGER 460 List 1295 S1149

NEW IDS PAPERTIGER 460G List $1394 $1199

NEC Spinwriters Call for Price

TELETYPE 43 KSR $1087

CENTRONICS 7J0 1 parallel interface ... NErW LOW $649 737 parallel interlace SUPER VALUE $829 779 w Tractor, List $1350 NFW

702 w Tractor, VFU, List $2480 , !:**

703 w Tractor, VFU, List $2975 L0W

704 w Tractor, VFU, List $2350 PRICES

Tl 810 Basic. List $1895 $1695

810 serial & Centronics style

parallel interlace. List $1940 $1735

810 w full ASCII IU LC), Vertical

Forms Control, Compressed Print . . $1895

Tl 820 KSR, List $2165 $1895

TI745w full ASCII, List $1695 $1399

COMPRINT 912 w parallel interface . $ 559

912 w serial inter-face. List $699 $ 589

AXIOM IMP I $ 699

MICROTEK. List $750 $ 675

OKIDATA Microline 80, List $949 649

Tractor Feed Option $ 99

RS232 Serial Interface $ 89

NORTH STAR HORIZON"

HORIZON 1 ASSEMBLED & TESTED

32K, Double Density, List $2695 $2279

32K, Quad Density, List $2995 ....... $2539

HORIZON 2 ASSEMBLED & TESTED

32K, Double Density, List $3095 $2619

32K, Quad Density. List $3595 $3049

48K, Double Density, List $3590 $3039

48K, Quad Density, List $4090 $3469

64K, Double Density, List $3830 $3239

64K, Quad Density, List $4330 $3669

FLOPPY DISK SYSTEMS

NORTH STAR MDS A Assembled, List $899 SPECIAL $ 719

Kit Version, List $799 $ 669

MORROWTHINKERTOYS" Discus2D.

List S1199 OUR PRICE $1019*

Discus2D, dual drive, List $1994 $1694*

Discus 2 • 2. A&T, List $1549 $1319*

Dual Discus 2 . 2, A&T, List $2748 . . . $2335* "Now includes CP M" 2.2 MICROMATION Megabox, DD w

8" drives, 1-megabyte, List $2295 $1949

2 megabyte, List $3095 $2629

MICROPOLIS 1041 MacroFloppy" w enclosure (no P.S.I, List $695 . $ 625

1042 MacroFloppy w case & AC PS. . $ 709 1053 Dual MetaFloppy' , List $1895 . . . $1695

VIDEO BOARDS

I/O Mapped SD COMPUTER VDB-8024,kit,List $370 $3191

Assembled, List $470 $ 399 1

XITEX SCT-100K, Kit ONLY $154.95

SCT 100A Assembled $174.95

SSM VB2 I/O. Kit, List $199 Call

Assembled & Tested. List S269 Call

Memory Mapped SSM VB1C, 16x64, Kit, List $179

Assembled & Tested, List $242 SSM VB3.80 Char ,4MHz,Kit, List S48.' Call

4 MH;, A&T, List $565 Call

INTERSYSTEMS, 16x64, A&T, List $165 $149

ESCON CONVERSION FOR IBM SELECTRIC

Complete w microprocessor controller find power supply. Factory built User installs solenoid assembly or it can be done at Escon factory at nominal cost. Parallel (TBS 80, Sorcerer, etc.), $575 $514 RS232 Standard Serial, List $599 ... 534

IEEh-<»88 (for PET). List $660 584

TRS 80 Cable 25

CALIFORNIA COMPUTER SYSTEMS

280 CPU BOARDS List S299 $269

DISK CONTROLLER 2422 L.st $399 . . $359

32 CASE STATIC List $710 $599

64K DYNAMIC BDARD List $699 $589

CPU BOARDS

(assembled unless noted I NORTH STAR Z80A (ZPB A Ai. $299 $254 CROMEMCO 4 MHz IZPU Wi. List $395 $335

4 MHz (SCC W), List $450 5382

INTERSYSTEMS (formerly Ithaca Audio)

new Series II Z 80. 4 MHz. List $395 . $349 SSM CB1 8080 A&T List $252

CB1A Kit. List S183

CB2Z 80 A&T. List S344

CB2 Kit, List S26J

DELTA Z 80. w'th I C $289

SD SBC 100. List $350 $298

SBC 100 Kit, List $295 $250

SBC 200. List $400 $332

SBC 200 Kit. List $320 $272

MEMORY BOARDS

32K SD ExpandoRAM Kit ONLY $289 T

ONLY$189without RAM chips

NORTH STAR 16K Dynamic RAM Boarrt.

A&T (RAM 16 A A). List $499 $420

16K Kit Version, List $449 . , . SPECIAL $299

32K A&T (RAM 32 A), List $/39 $620

32K Kit, List $669 SPECIAL $499

CROMEMCO 16KZ-W, List $495 $419

64KZ W, List $1795 1485

MEASUREMENT SYSTEMS & CONTROLS

(Guaranteed performance, incl labor parts 1 yrl DM6400 64K Board w all 64K, $795 . . . $659

DM4800 with 48K. List $695 $589

DM3200 with 32K. List $595 $509

DMB6400 64K Board w all 64K $859

DMB4800 with 48K $789

MORROW SuperRAM all static, all A&T

16K. 4 MHz or 2 MHz, List $349 $299

32K, 4 MHz, List $699 $629

16K Memory Master, List $399 $339

24K Memory Master, List $549 ....... $465

INTERSYSTEMS (formerly Ithaca Audiol

8K Static 2 MHz, A&T. List $165 $149

8K Static 4 MHz. A&T. List $195 $176

16K Static 2 MHz, A&T, List $475 ... $427 16K Static 4 MHz, A&T, List $495 . . $445 64K Dynamic, List $995 $895

CALIFORNIA COMPUTER 16K Static. A&T, List $349.95 $259

FLOPPY DISK CONTROLLER BOARDS

NORTH STAR, DD.

Assembled, List $499 $399

MORROW Disk Jockey 1, A&T ($213) . $189

Disk Jockey 2D, A&T, List $479 $429

SD Versafloppy 1, Kit, List $250 $2121

Versafloppy II, DD Kit, List $350 $297 1

Versafloppy II, DD, A&T. List $430 $365 t

DELTA double density A&T ($385) $345

CONDUCTOR, double density A&T . . . $269

INTERSYSTEMS FDC-2, A&T, $495 . . . $439

MICROMATION Doubler, DD, A&T . . . $399

TARBELL Floppy Disk Interlace Kit $199

double density, A&T, List $495 . $444

NEW CROMEMCO

DOUBLE DENSITY

DISK CONTROLLER

List $595 OUR PRICE $505

SHIPPING AND INSURANCE Add $2 50 lor boards. $6toi Selectnc Convener or Floppy Disk Drives, $7 bO lor Floppy D<s« Syslems. $l5lor Horizon SHIPPED FREIGHT COLLECT SupetBntir anri t i nrintorc rnnia< us for shinnma information on other Inrmiruils and printers.

Centronics

and T, I. printers. Con tat us for shipping mlorniation on other terminals and prm

Above prices re

i Lon iai us for snip piny it iiurn itiuuii un uinci iwniuiaia ™«j m< ■■ ■ «*•■ >»■

fled a 2% cash discount lorder prepaid prior to shipmenl) Add 2% lo prices for credi: card meters C.O.D.'s. etc. Prices are subject to change and otters subiecl to withdrawal wm-.oul nonce

- WRITE FOR FREE CATALOG

MiniMicroMart, Inc.

Circle 320 on inquiry card.

1618 James Street. Syracuse NY 13203 (315) 422 4467 TWX 710-541-0431

Terminals and Printers!

TELEVIDEO TVI-912C

SOROC

TI-810

Upper and lower case, 15 baud rates: 75 to 19,000 baud, dual intensity, 24 x 80 character display, 12 x 10 resolution. Numeric pad. Programmable reversfble video, auxiliary port, self-test mode, protect mode, block mode, tabbing, addressable cursor. Microprocessor controlled, programmable underline, line and character insert/delete. "C" version features typewriter-style keyboard. List $950

OUR PRICE'CALL

920C (with 11 function keys, 6 edit keys and 2 transmission mode keys. List $1030

CALL Intertec

EMULATOR

Software compatible with a Soroc IQ-120, Hazeltine 1500, ADM-3A or DEC VT-52. Features block mode transmission and printer port; 12" anti-glare screen; 18-key numeric keypad; full cursor control. List $895

OUR PRICE S749

NEW INTERTUBE III

List $995 ONLY $749

12" display, 24 x 80 format, 18-key numeric keypad, 128 upper/lower case ASCII characters. Reverse video, blinking, complete cursor addressing and control. Special user-defined control function keys, protected and unprotected fields. Line insert/delete and character insert/delete editing, eleven special line drawing symbols.

IQ-120

List $995

SPECIAL

IQ-140 List $1495 SPECIAL $1149

HAZELTINE

1500 ONLY

$879

1410 w/numeric keypad. List $900 $749

1420 w/lower case and numeric pad .... 849

1510, List $1395 1089

1520, List $1650 1389

NEC SPINWRITER™

Terminal/Keyboard as well as

RO Printer Only models available.

CALL FOR PRICES!

CENTRONICS

PRINTERS

NEW 730, parallel, friction, tractor . . . $649

NEW 737 parallel, friction, tractor $829

779-2 w/tractor (same as TRS-80 Line

Printer I), List $1350 _

702 120 cps, bi-direct., tractor, VFU .... Nfcw

703 185 cps, bi-direct., tractor, VFU .... LOW

704 RS232 serial version of 703, $2350 . . PRICES

TI-810 Basic Unit, $1895 . ONLY $1695 TI-810 w/full ASCII (Lower case), vertical

forms control, and compressed print . $1895 TI-745 Complete printing terminal with acoustic coupler, List $1695 .... $1399

PAPER TIGER

1 ft

IDS-440 Paper Tiger, List $995. $695

w/graphics option, incl. buffer, $1194 . . $789 TRS-80 cable 45

NEW IDS PAPERTIGER 460List S1295 . S1149

NEW IDS PAPERTIGER 460G List S1394 S1199

NEW IDS 460

QUALITY PRINTING AT MATRIX

SPEED-LOGIC SEEKING

PROPORTIONAL SPACING

w/auto text justification

RNRD€X

OP9500/DP9501 PRINTERS

S1399 SI 399

ONLY $649

DP-9500. List S1650 DP-9501. List S1650

OKIDATA Microline80

Tractor Feed Option $99

Serial interface $89

AXIOM IMP I $699

COMPRINT 912 w/parallel interf. $559 912 w/serial interface, List $699 $589

MICROTEK, List $750 $675

ANADEX 80-Col. Dot Matrix $849

Above prices reflect a 2% cash discount (order prepaid prior to shipment). Add 2% to prices for credit card orders, C.O.D.'s, etc. Prices are f.o.b. shipping point. Prices are subject to change and offers subject to withdrawal without notice. WRITE FOR FREE CATALOG.

MiniMicroMart, Inc.

1618 James Street, Syracuse NY 13203 (315) 422-4467 twx 710 541-0431

Circle 321 on inquiry card.

Unclassified Ads

UNCLASSIFIED POLICY: Readers who are soliciting or giving advice, or who have equipment to buy, sell or swap should send in a clearly typed notice to that effect. To be considered for publication, an advertisement must be clearly noncommercial, typed double spaced on plain white paper, contain 75 words or less, and include complete name and address information. ,

These notices are free of charge and will be printed one time only on a space available basis. Notices can be accepted from individuals or bona fide computer users clubs only. We can engage in no correspondence on these and your confirmation of placement is appearance in an issue of BYTE.

Please note that it may take three or four months for an ad to appear in the magazine.

FOR SALE: Heath H-11A: 32 K bytes, assembled, serial and parallel interfaces, high-speed paper-lape punch/ reader, and extended arithmetic chip, Everything for $1600. Chris Martin, 604 S Remington, Anglelon TX 77515, (713) 424-1900 evenings.

FOR SALE: KIM-SI board; $175, 8 K programmable memory; $125, CRT controller board TH3216 (32 by 16); $175. All working, Canadian funds, postage paid in Canada. Will sell to first arrived. Denis Beauregard, 2425 rue-Saint-Antoine, Lachine Quebec, H8S 1V9 Canada.

FOR SALE: SwTPC 6600 with 36 K programmable memory, MF-68 dual minifloppy, PR-40 printer, four parallel and one serial I/O ports. Price negotiable. Ken Staton, POB 10490, Stanford CA 94305, (415) 329-9888.

FOR SALE: Three S-100 8 K static memory boards. They have been in use for over one year without a memory error. Two are Godbout and one is a ProcessorTech 8KRA. $125 each or $325 for all three. Jerry Bass, 2326 Piatt Dr, Martinez CA 94553, (415) 445-2435.

FOR TRADE: Diablo Hytype I multistrike ribbons (recycled, 37 ea) and new 8-inch floppy disks. Will trade one for one for 5-inch floppy disks. Prefer BASF, DYSAN, or Scotch (no Verbatim). Paul Holliday, 4807 Arlene St,San Diego CA 92117.

FOR SALE: Polymorphic Systems 8813. An S-100, 8080A-based system with keyboard, 9-inch monitor, and dual single-sided drives. Confidence package and Wordmaster text editor included. John D Flynn, POB 563, East Longmeadow MA 01028, (413) 525-3981.

FOR SALE: BPI Business General Ledger Package for Commodore PET. Original, complete with manual and instruction booklet. Robert O Williams, 9949 Hawley Rd, El Cajon CA 92021, (714) 561-4397.

FOR SALE: Two WHA-11-16 16 K by 16-bit memory boards for H-11A or LSI-11. Perfect working condition; making room for disk controller. $350 each. G W Schreyer, 412 N Maria, Redondo Beach CA 90277, (213) 376-9348,

FOR SALE: BYTE #1 thru December 1978. Also, extra copy of #1. PerSci 1070 disk controller and INFO 2000 S-100 adapter card. Best offers. Scott Crumpton, 233 Space Sciences Research Bldg, University of Florida, Gainesville FL 32611.

FOR SALE: Anderson Jacobson AJ 841 I/O printerterminal. IBM Selectric mechanism. 130 ch/line. New. Plus, Apple parallel-printer interface card. $750. Virginia Stern, 215 E 11 St, New York NY 10003,(212)477-6634.

WANTED: I am interested in contacting computerists who are doing advanced forecasting on both stock and commodity markets, I retired early and have done very well in speculation through system approach. Ted Broder, POB 407, Flushing NY 11363.

FOR SALE: Hazeltine 1500 terminal. Brand new and unused. Unopened in original carton. $1000 plus shipping. Bill Leeson, 1546 Becklow Ave, Baltimore MD 21220, (301) 574-4797 evenings, (301) 628-4173 days.

FOR SALE: High-speed paper-tape punch. 120 character/second Tally Model P-120A. Includes manual and Whiteford Laboratory Model P1-12A paper-tape winder. $150 for everything. Richard A Libby, 505 Cascade, Richland WA 99352, (509) 946-7341.

FOR SALE: A reliable S-100 computer in a solid oak cabinet. Partial component list of the computer is: Z80 processor (2 MHz), 52 K programmable memory, 8 K erasable-programmable read-only memory, PerSci floppy disk and controller, cassette and PPT I/O, video display, Memory Map Video, Dazzler, 40-column printer, and much more. Extensive software library and documentation included. All for $4200. Write for detailed description. Robert Alkire, 220 E Hellman Ave, Monterey Park CA 91754.

The Sight of Musk

Digital Harmony

by John Whitney

BYTE BOOKS is pleased to offer DIGITAL HARMONY a

major new work by John Whitney, a pioneer of the special effects technology used in STAR WARS and 2001: A SPACE

ODYSSEY. His book explores the special union of music and computer graphics, and expands the frontier between sight and sound, synthesizing the two to create a new art form. Whitney tells how it's done, provides a thorough theoretical background, and includes listings and programs for those interested in joining in the discovery of this new art form. DIGITAL HARMONY lays the foundation for audio-visual art made possible by microcomputers. It is must reading for all art, music and home computer enthusiasts.

Illustrated in Color.

382 February 1981 © BYTE Publications Inc

ISBN 07-0700 I 5-X Price S2L95

Please remit in U.S. funds

>r draw on a U.S. Bank

Please send D copies of

Digital Harmony

Company

Street

City

State/Province

D Check enclosed in the amount ot $_ □ Bill Visa D Bill Master Charge

Card No.

Exp. Dace .

Add 75c per book to co postage and handling.

Available in January

KUTE

K1IVS

Call TOLL FREE: 800-258-5420 or Mail To:

70 Main Street, Peterborough. N.H. 034S8

FOR SALE: Dr. Dobb's Reference Journal, Vol I, $10. Basic Computer Games by Dave Ahl, $6. Basic Software Library, R W Brown, Vol I, $15. Scelbi's three volumes: 8080 Editor, Assembler, and Monitor with hexadecimal and octal listings and full discussion of programs and their use, $15. Add $1 shipping for each book or take all for $45 postpaid. R Mendelson, 27 Somerset PI, Murray Hill NJ 07974.

FOR SALE: Centronics 101A 165 cps printer. $400. Parallel interface. Logic board #2 needs repair or replacement. Bill Webb, 180 Winard Ave, Sellersville PA 18960, (215) 257-1161.

FOR SALE: 32 K Exidy Sorcerer computer; $685. SD VR8024 video board; $295. S-100 mainframe, 28 A power supply; $245. SSM VB1B video board; $100. Hank, (714) 245-5054 weekends or evenings after 9 PM.

FOR SALE: Rockwell AIM-65: 4 K programmable memory, BASIC and Assembler read-only memories. Power supply and case. One-year-old; $550. Greg Crandall, (213)991-7871.

FOR SALE: IMSAI 80B0A mainframe, fully loaded with North Star 280 processor and MDS single-density minifloppy. 44 K of programmable memory. Cromemco TV-Dazzler color graphics. Processor Tech VDM-1 video board and 3P + S I/O board. All documentation and over thirty disks of software. Working well for over three years. Best offer over $2500 takes it. Will not unbundle. Tom Gantner, 233 Woodbourne Dr, St Louis MO 63105.

FOR SALE: Compucolor II: Model 5 (32 K programmable memory), 117-key keyboard, two disk drives, Soundware audio, game paddles, programming manual, maintenance manual, and more than $500 in software. Many games and utilities. Everything in excellent condition. Pete Pacione, 2952 N Meade, Chicago IL 60634, (312) 889-2674.

NEEDED: I want to know Loglan. I want learning aids, Loglan pen pals, or address of the Loglan Institute. Bob Peterson, Apt 1203, 525 E Semoran Blvd, Fern Park FL 32730.

FOR SALE: Jade Big Z Z80A processor for S-100 bus. Fully assembled; will sell for $110. Doug Kelley, 3312 Mae Dr, Warren OH 44481,(216)824-3113.

FOR SALE: Printer: 165 cps, excellent condition, variable character size, double-width characters, graphics can be added, same mechanism as the IDS printers; $399. S Levine, 1802 Melville St, Ocean NJ 07712, (201) 531-8305 after 6 PM.

WANTED: 6502 macro cross assembler program that runs on 6800 or 6809 machines. Must have good documentation. J L Peterson, 7150 N Terra Vista #704, Peoria IL 61614.

FOR SALE: IBM Selectric II (Micro Computer Devices, Selecterm, system 9710) interfaced for the SOL-20. This Selectric is loaded with all the options. It has tractor feed, dual pitch, V2 backspace, self-correction, and software for a North Star drive. Best offer. Joe Lancaster, 1931 Cedar Ridge Dr #18, Stockton CA 95207, (209) 957-7018.

FOR SALE: Intersil IM-6101 programmable interface element. Compatible with the IM-6100 microcomputer, the PIE provides control signals to peripheral devices for reading or writing on the DX bus by activating the write and read control lines with input/output transfer instructions. Excellent like-new condition. Asking $1500. Glenn Cardinal, (914) 471-9500.

FOR SALE OR TRADE: IMSAI single-board 8048 EROM computer(kit)for$395, cost $499; IMSAI 3 A, 5 V power supply for 8048 single-board computer (never used) for $75, cost $99; IMSAI programmable memory (kit form) for $110, cost $149; or will trade for a video terminal. George Kimble, 203 Eleventh St, Genoa OH 43430,(419) 855-7743 days, (419) 855-4082 evenings.

WANTED: Would like to exchange TRS-80 newsletters with other user groups. I want to exchange the data on disks so I will not need to rekey info. If you know of a group that does newsletters exchange on disk, please let me have their mailing address so I can contact them. Also, give them my address so they can contact me. S80 userNEWSLETTER, POB 28355, Columbus OH 43228.

FOR SALE: Apple II+ (48 K), DOS 3.3, disk with controller, all manuals, Sanyo B & G 12-Inch monitor, Videx 80-column board, Hayes mlcromodem, Qume 5/45 printer, seriai l/F card, RF modulator, Easy Writer professional word processing system, Apple Dow Jones Evaluator, Data Capture software. All purchased new on 11/7/80. $6000 or best offer. Whitley Strieber, 300 E 75th St, New York NY 10021, (212) 744-5603.

FOR SALE: HP-67 calculator with standard pack, math pack, manuals, soft leather and plastic cases, and security cradle. All in excellent condition. Best offer. Mark Bellon, 20 Elliot Ave, Centereach NY 11720, (516) 585-5530.

FOR SALE: Commodore PET with 24 K bytes of memory, library of purchased programs, and vinyl cover. $595. Richard Wiesenthal, 145 Central Park W, New York NY 10023,(212)874-0190.

FOR SALE: Used Texas Instruments Silent 700 portable terminal, Model 745. Purchase price last yearwas $1600. Available now for $900. A G Fromuth, (603) 625-2932.

FOR SALE OR TRADE: Digital Group Z80 computer (26 K), dual Phi-Decks, Printer B, extra I/O board, lots of software (including Manuscrlptor by MicroWorks and Sargon); $1500 or will trade for Apple. Mark Weber, 6515 Wydown, Box 3812, Clayton MO 63105,(314) 863-7026.

BOMB

Onaoina Moniti

or Box

Author(s)

BYTE's

Article ft Page

Article

1

30

Radio Shack's Daisy Wheel Printer II

Kola

2

36

An Extremely Low-Cost Computer Voice

Response System

Anderson

3

44

A Computer-Controlled Tank

Ciarcia

4

68

A Beginner's Guide to Spectral Analysis, Part 1

Zimmermann

5

96

Infinite BASIC and Infinite Business

Mitchell

6

106

A Pascal Library Unit for the Micromodem II

Woteki

7

142

Dynamic Memory: Making an Intelligent Decision

Malakoff

8

152

Stacking Strings in FORTH

Cassady

9

164

Articulate Automata

Fons and Gargagliano

10

202

IRV, a TRS-80 Utility Program

Li

11

220

Image Processing With a Printer

Calkins

12

253

The Heath H-14 Printer

Rehm

13

262

Zork, The Great Underground Empire

Liddil

14

312

A/D and D/A Conversion—An Inexpensive

Approach

Mikel

15

318

Turn Your COSMAC VIP into a Frequency

Counter

Modla

16

326

A Heating and Cooling Management System

Hall

17

332

Modifying the SwTPC Computer

Weaver

FOR SALE: TRS-80: 16 K, Level II wilh numeric keypad. $550. Heath H-14 printer, 110 thru 9600 bps. Adjustable pin feed. TRS-232 interface for connection to TRS-80 without expansion interface. Both for $550. Tony Greaves, 1370 Niagara Falls Blvd, Tonawanda NY 14150, (716) 838-4957.

FOR SALE: TEL-IT message and inventory computer system. Z80-based terminal with 16-character readout (no CRT). Built-in R/W tape, real-time clock. Will interface to printer. Cost $900; asking $500. Bob Loveless, (714)689-7800.

FOR SALE: IBM 1980 Buffered Terminal (Model 9) and IBM 7441 Control Unit. Used less than one year by credit company. In perfect working order; terminal has Selectric-type ball and could be converted into printer. Has transmit and receive abilities compatible with Bell Systems. $600 plus shipping. Doug Arnold, Rte #1, Box 278, Hanceville AL 35077, (205) 734-0390 work.

FOR SALE OR SWAP: TI-59, reconditioned and fully operational with Master Library Module. No case or manuals. Will sell for $100 or swap for functional PC100C printer. Robin Haynes,352A Washington Rd, West Point NY 10996.

FOR SALE: Brand-new Heath H-8 microcomputer with 4 K memory board, serial/cassette interface, BASIC tape, all assembly and operating manuals. Fully assembled and tested. Total value $614 (assembled) or $489 (kit); you get them assembled for only $275, and I pay shipping. Robert James, 12010 Cabana Ln, Austin TX 78759, (512)837-4749.

FOR SALE: Intel System 80/10 computer with 19-inch chassis, SBC-635 power supply, fans, four-slot card cage, SBC-80/10 (single-board computer), SBC-016 (16 K programmable memory), SBC-416 (16 K programmable read-only memory), SBC-108 (8 K programmable memory, 4 K programmable read-only memory, six parallel, one serial ports). Also, haveextra four-slot card cage with SBC-416, SBC-104 (like 108 but 4 K programmable memory), MCS-80 (SBC card unpopulated). Twenty-six 2708 erasable-programmable read-only memories included. Will sell for about 25% of list price or swap for S-100 bus system. John Gill, Rte 5, Box 370, Blountville TN 37617, (615) 323-2453.

November BOMB Results

Steve Ciarcia found the mark with "Home In on the Range: An Ultrasonic Ranging System" (page 32), which came in first in the voting. Steve receives the $100 first-place prize.

Second place was won by one of the articles on the issue theme of highresolution graphics, "Micrograph, Part 1: Developing an Instruction Set for a RasterScan Display," by E Grady Booch (page 64). He gets the $50 second-place prize.

Graphics-theme articles also captured the next two positions: "A Simplified Theory of Video Graphics, Part 1" by Allen Watson III (page 180) placed third, and "The Future of Computer Graphics" by Bruce Eric Brown and Stephen Levine (page 22) took fourth.

February 1981 © BYTE Publications Inc 383

Reader Service

Inquiry No.

Page No.

120 201

263 267

33 113

76 189

80 134 307

68 299

10

18 182 191

216 279

156 257

329 246 247 127

297 16 317 172 175 118 176 117 233 42 232 61 183 272 109

104 227

295

51

159

50 231 100 161

63 184

72 237

79

52 270 1 282 262 112

266

96

206

110 147 210 242 301 202 146

84 171 258 226 224

20 195 173

Aardvark Software Inc 285

Aardvark Software Inc 291

Abbott, Robert 356

AB Computers 349

ABM Products 134

Action Computer 111

Adaptive Data 8 Energy Sys 362

Adaptive Systems Inc 310

Advanced Comp Prod 370, 371

ALF Products 230

ALL Electronic 354

Alpha Omega Comp Sys 354

Alpha Byte Storage 59

Alphacom Inc 177

Altos 121

Am Comp & Telecom Corp 275

Am Micro Prod Inc 128

American Square Comp 201

AMSI Corp 362

Anadex 113

Ancrona 361

Apple Computer 13

Applied Analytics 182

Artec Electronics 24

ASAP 267

Ashton-Tate 277

ATV Research 356

Automated Equip Inc 299

Axlon Inc 311

Ballantine Books 304

BASF Systems 231

Beckian 350

John Bell Engineering 357

Beta Comp Devices 315

Beta Comp Devices 352

The Bit Bucket 283

Bower-Stewart 8 Assoc 329

Buss/Charles Floto 333

BusinessWeek 193

BYTE Back Issues 323

BYTE Books C 111, 99, 382

BYTE Subscriber 291

BYTE WATS 293

C 8 A Associates 360

Calif Comp Systems 20, 21

Calif Digital 374,375

Cambridge Develop Labs 256

Cavri Systems Inc 258

Central Data 183

Chrislin Industries 259

Clev Con Comp 8 Compnts 181

Colonial Data Serv Corp 311

CompuMart 72, 73

CompuMart 311

CompuServe 104, 105

Computer Age Inc 268

Computer City 356

Computer Disc of Am 158

The Computer Factory 69

Computerland 163

Computer Marketing Corp 306

Comp Prof Book Club 241

Computer Room, The 22

Computer Shopper 360

Computer Specialties 88, 89

Computer Tech Assoc 234

Computer Warehouse 125

Computers R Us 84, 85

Computerware 310

Computers Wholesale 154

Computers Wholesale 236

Computex 108

COMPUTIME268

Compuview Products Inc 117

Concord Comp Components 315

Corvus Systems 127

Cover Craft 90

CPU Shop, The 355

Cromemco 1, 2

Custom Business Comp 358

Custom Peripherals 354

Crystal Computer 175

Cybernetics Inc 317

B. Dalton Bookseller 203

Data Discount Center 112

Data Hardware 354

Datasouth Computer Corp 146

Datasouth Computer Corp 294

Delta Products 171

DG Electronics Develpmt 215

Digiac Corp 296

Digicomp Research Corp 322

Digital Systems Eng 362

Digital Graphic Systems 292

Digital Marketing 213

Digital Pathways 133

Digital Research 255

Digital Research Computers 351

Discount Software Group 305

Disc/3 Mart Inc 303

Dual Systems Control Corp 26

DMA 286

Dynacomp Inc 257

Inquiry No.

Page No.

170 122 293

207 198 188 149 220 229

19

83 128

41 250 193

25 305 145

38 150 166 209 130 131 291 196

60

13 7 9

254

44

45

168

280

62

21

70

154

27

28

180

121

29

264

5

6

313

314

230

287

302

298

259

285

67 225 194

34 238

89 169 222 281 275 177 124 204

43 152

303

249

36

78

174

71

46 139

58 165

Dymarc Industries Inc 254

Ecosoft 188

Educational Courseware 360

Electronic Control Tech 295

Electronic Specialists 290

Ellis Computing 278

Epson America Inc 217

Escon 301

Essex Publishing Co 308

Exatron Inc 25

Faircom 132

Farnsworth Comp Center 194

John Fluke Mfg Co 71

Fordham 346

Milton Foster 283

General Business Computer 34

Gimix 362

Godbout Electronics 210, 211

Mark Gordon Computers 66

H 8 E Computronics 218, 219

H 8 E Computronics 247

Hanley Engineering 295

TSE/Hardside 196

TSE/Hardside 197

Harris Corp 360

Hayden Book Co Inc 287

Hayes Microcomp Prod Inc 103

Heath Company 17

High Technology Inc 10

High Technology Inc 12

MG Hill 283

Hobbyworld Electronics 348

Houston Instruments 79

Houston Instruments 79

Hughes Aircraft 252

IDM 358

Imprint Software 107

IMS International 27

Info Unltd Software 115

Innovative Sftw Appl 229

Integral Data Sys 49

Integral Data Sys 51

Integrand 264

Intelligent Control Sys 188

Intertec Data Systems 53

Ipex Int'l Inc 354

Ithaca Intersystems 8

Ithaca Intersystems 9

Jade Computer Prod 366, 367

Jameco Electronics 368, 369,

JDR MICRODEVICES309

JHC Info Products 358

Jepsan Group K Inc 362

Jordon, Jeff MBA 360

JR Inventory Control 352

Kemco LTD 91

Kirk Shrewsbury 283

Konan Corp 61

Laboratory Microsystems 358

Lax Computer Products 162

Lax Computer Products 303

Leapac Services 284

Livermore Data Sys Inc 60

LNW Research 316

Lobo Drives Int'l 137

LomasData Prod 254

Londe, Parker 8 Michels 302

Macrotronics Inc 358

Magnolia Microsystems 356

Mann, Charles 8 Assoc 260

Marway Products Inc 190

Marymac Industries Inc 293

Maxell Data 75

MBC Systems Inc 226

McGraw-Hill Magazines 168, 169

Meas Sys 8 Controls 29, 129

Mega Systems Inc 362

Meta Technologies Corp 335

Micro Age Computer Store 63

Micro Appl Group (MAG) 123

Micro Architect 258

Micro Business World 116

Micro Computer Discount 332

Micro Data Base Sys 139

Micro Focus 93

Micro House 80

Micro Management Sys 205

Micro Pathways 100

Micro Pro International 245

Inquiry No.

Page No.

148 64

164 97

185

103 98

105

87

17

82

47

276

73

256

153

244

141

286

320

321

138

37

15

88

192

132

102

186

59

69

53

107 325 155 142 326 212 40 239 179 223

144 49 163 178 243

75 265 304 260 300 190

3

4

26

48

322

323

157 23

284

167

85

54

318

319

268

12

67

312

292

235

151

111

93

252

240

261

Micro Works, The 216

Micro World 109

MicroAce 239

MicroByte 147

Microcomputer Tech Inc 269

MicroDaSys 161

Micromail 150

MicroMint 283

Micropolis Corp 165

MICRO-SCI 135

Microsette 23

Microsoft 131

Microsoft (Cons Prod Div) 81

MicroTech Exports 356

Microware Sys Corp 118

Mikos 350

Miller Microcomputer Serv 228

Mindex Infosystems 328

Mini Computer Suppliers 206

Mini Comp Supply (MCS) 358

Mini Micro Mart 380

Mini Micro Mart 381

Miro Computers Inc 204

Morrow Designs 65

Mountain Computer Inc 19

Mountain Computer Inc 136

mpi 279

MT Microsystems 199

MTI Inc 160

Mt. View Press 272

MUSYS 102

Nautilis Systems 114

NEBS 92

Netronics62, 224, 249

NNC Electronics 167

Northern Tech Books 281

NRI Schools 209

Ohio Data Products Corp 166

Ohio Scientific Instr C IV

Ohio Scientific Instr 184, 185

OK Machine 8 Tool 207

Oliver Advanced Eng 283

Olympic Sales Co 297

Omega Micro Computers 70

Omega Research 317

Omega Sales Co 263

Omikron 303

onComputing 225

Optimal Technology 208

Orange Micro 83

Orthocode Group 238

Osborne/McGraw-Hill 261

OSM Computer 323

Owens Associates 1 56, 157, 326

Pace Inc 120

Pacific Exchanges 354

Pacific Exchanges 362

Page Digital 353

Pan American Elec 361

Passport Design 276

Passport Design 333

PCD Systems Inc 6

Percom Data 7

Percom Data 35

Percom Data 35

Percom Data 35

Percom Data 35

Personal Computer Festival 319

Personal Computer 232

Personal Software 31

Petronics 358

Phase One Systems 227

Pickles 8 Trout 248

pk systems inc 1 34

Power One Inc 94

Priority One 376, 377

Priority One 378, 379

The Purchasing Agent 354

QT Computer Sys 16

QT Computer Sys 162

QT Computer Sys 364, 365

Quality Computer Parts 360

Quality Software 313

Qantex 223

Quasar Data Products 173

Quay Corp 141

Quest 347

Quiet Designs Inc 319

Quintrex Inc 354

Inquiry No.

Page No.

214 R 8 B Computer Systems 298 241 Racet Computes 321

22 RCA 28

106 RKS Enterprises 166

245 RNB Enterprises 329

213 Rochester Data 297

234 S 8 M Systems 313

91 S-100lnc138

309 SC Digital 362

140 Scientific Eng Labs 206

2 Scion Corp 5

211 SciTronics Inc 297

283 Scotia Software 358

65 Scottsdale Systems 110

181 Seattle Computer Prod 265

218 Shepardson Microsystems 299 ' Kirk Shrewsbury 283

11 Shugart 14, 15

" Sinclair Research 151

35 SKP Electr 283

290 Sluder360

14 Small Business Appl 18

30 Snapp Inc 55

160 Softech Microsystems 235

39 The Software Federation 67

200 The SoHo Group 291

205 The SoHo Group 293

• Solid State Sales 82

90 Sorrento Valley Assoc 138

129 Southern Semiconductors 195

324 Southwest Tech Prod Corp CM

158 Spectrum Software 233

8 SSM 1 1

219 Street Electronics 301 126 SubLOGIC 192

311 Sunny Int'l 363

• SuperSoft 98, 179, 191,295, 307 101 Sybex 159

• Synchro Sound 101, 256 32 System Kontakt Inc 58

294 SZ Software Sys 360

123 Tarbell Electronics 189

95 Tech Sys Consultants (TSC) 145

277 Technical Innovations 356

162 Tec-Mar Inc 237

55 Tercer Medio 96 271 Terminal Data 356 199 Texas Comp Sys 290

' Texas Instruments 95

99 3M Company 153

215 Thunderware 300

133 Mitchell E Timin Eng Co 200

" Robert Tinney Graphics 155

115 TNW Corp 180

273 Toolsmith, The 356 328 TPA 283

77 TransNet122

• United Software of Am 76, 77 137 Univair Inc 204

316 US Micro Sales 372, 373

135 US Robotics 202

143 US Robotics 208

274 US Robotics 356 197 VANDATA 289

56 Vector Graphics 97

31 Verbatim 56,57

327 Vertical Data Sys Inc 283

296 Videx 360

94 Vista Computer Co 143

289 Vista Computer Co 359

119 Voicetek1B7

187 Votrax 273

251 VR Data 346

253 Wameco 348

• Westico Inc 148, 149,354 24 White Computer Sys 33

• Whitesmith's Ltd 243 221 Wild Hare Comp Sys 301 288 Wintek Corp 358

217 Winterhalter 8 Assoc 299

308 Worldwide Electronics 362

310 WW Component Supply Inc 363 « Zobex 119

To get further information on the products advertised in BYTE, fill out the reader service card with your name and address. Then circle the appropriate numbers for the advertisers you select from the list. Add a 15-cent stamp to the card, then drop it in the mail. Not only do you gain information, but our advertisers are encouraged to use the marketplace provided by BYTE. This helps us bring you a bigger BYTE. The index is provided as an additional service by the publisher, who assumes no liability for errors or omissions. * Correspond directly with company.

384 February 1981 © BYTE Publications Inc

KV 11; READER SERVICE

For fastest service transfer mailer label from wrapper to coupon provided at the right. Requests cannot be honored unless zip code is given. This card valid for 90 days only. NOTE—If label is missing or defaced fill out coupon carefully—PLEASE PRINT—this is the only way to get requested material to you.

1 21 41 61 81 101 121 141 161 181

2 22 42 62 82 102 122 142 162 182

103 123 143 163 183

104 124 144 164 184

105 125 145 165 185

106 126 146 166 186

107 127 147 167 187

108 128 148 168 188

109 129 149 169 189

110 130 150 170 190

111 131 151 171 191

112 132 152 172 192

113 133 153 173 193

114 134 154 174 194

115 135 155 175 195

116 136 156 176 196

117 137 157 177 197

118 138 158 178 198

119 139 159 179 199

120 140 160 180 200

Name .

February 1981 4121

|Title)

Address. City

. fCompany)

.State.

-Zip.

3 23

43

63

83

4 24

44

64

84

5 25

45

65

85

6 26

46

66

86

7 27

47

67

87

8 28

48

68

88

9 29

49

69

89

10 30

50

70

90

11 31

51

71

91

12 32

52

72

92

13 33

53

73

93

14 34

54

74

94

15 35

55

75

95

16 36

56

76

96

17 37

57

77

97

18 38

58

78

98

19 39

59

79

99

20 40

60

80

100

201

221

241

261

281

301

321

341

361

381

202

222

242

262

282

302

322

342

362

382

203

223

243

263

283

303

323

343

363

383

204

224

244

264

284

304

324

344

364

384

205

225

245

265

285

305

325

345

365

385

206

226

246

266

286

306

326

346

366

386

207

227

247

267

287

307

327

347

367

387

208

228

248

268

288

308

328

348

368

388

209

229

249

269

289

309

329

349

369

389

210

230

250

270

290

310

330

350

370

390

211

231

251

271

291

311

331

351

371

391

212

232

252

272

292

312

332

352

372

392

213

233

253

273

293

313

333

353

373

393

214

234

254

274

294

314

334

354

374

394

215

235

255

275

295

315

335

355

375

395

216

236

256

276

296

316

336

356

376

396

217

237

257

277

297

317

337

357

377

397

218

238

258

278

298

318

338

358

378

398

219

239

259

279

299

319

339

359

379

399

220

240

260

280

300

320

340

360

380

400

401 421

402 422

403 423

404 424

405 425

406 426

407 427

408 428

409 429

410 430

411 431

412 432

413 433

414 434

415 435

416 436

417 437

418 438

419 439

420 440

441 461 481

442 462 482

443 463 483

444 464 484

445 465 485

446 466 486

447 467 487

448 468 488

449 469 489

450 470 430

451 471 491

452 472 492

453 473 493

454 474 494

455 475 495

456 476 496

457 477 497

458 478 498

459 479 499

460 480 500

501 521 541

502 522 542

503 523 543

504 524 544

505 525 545

506 526 546

507 527 547

508 528 548

509 529 549

510 530 550

511 531 551

512 532 552

513 533 553

514 534 554

515 535 555

516 536 556

517 537 557

518 538 558

519 539 559

520 540 560

561

581

562

582

563

583

561

584

565

535

566

586

567

587

568

588

569

589

570

590

571

591

572

592

573

593

574

594

575

595

576

596

577

597

578

598

579

599

580

600

601 602 603 604 605 606 607 SOS 609 610 611 612 613 614 615 616 617 618 619 620

621 641

622 642

623 643

624 644

625 645

626 646

627 647

628 648

629 649

630 650

631 651

632 652

633 653

634 654

635 655

636 656

637 657

638 6=8

639 659

640 660

661 681

662 6S2

663 683

664 684

665 685

666 686

667 687

668 688

669 689

670 69D

671 691

672 692

673 693

674 694

675 695

676 696

677 697

678 698

679 699

680 700

bl I C J HUIVIH is your direct line to the editor's desk. Each month, the two top-rated authors receive bonuses based on your votes. To cast your vote, first look at the list of this month's articles and corresponding article numbers |located in the unclassified ads section on the page preceding the Reader Service list), then rate each article as Excellent. Good, Fair, or Poor by circling the appropriate number in each column below. Your feedb£c.'< helps to produce the best possible magazine each month.

Article No.

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

Excellent

801

805

809

813

817

821

825

829

833

837

841

845

849

853

857

861

865

869

873

877

Good

802

806

810

814

818

822

826

830

834

838

842

846

850

854

858

862

866

870

874

878

Fair

803

807

811

815

819

823

827

831

835

839

843

847

851

855

859

863

867

871

875

879

Poor

804

808

812

816

820

824

828

832

836

840

844

848

852

856

860

864

868

872

876

880

Comments

BITE

READER SERVICE

February 1981 4121

Name .

For fastest service transfer mailer label from wrapper to coupon provided at the right. Requests cannot be honored unless zip code is given. This card valid for 90 days only. NOTE—If label is missing or defaced fill out coupon carefully—PLEASE PRINT—this is the only way to get requested material to you.

jTitle).

.(Company)

Address. City

. State.

20

21 41

22 42

23 43

24 44

25 45

26 46

27 47

28 48

29 49

30 50

31 51

32 52

33 53

34 54

35 55

36 56

37 57

38 58

39 59

40 60

61

81

62

82

63

83

64

84

65

85

66

86

67

87

68

SB

69

89

70

90

71

91

72

92

73

93

74

94

75

95

76

96

77

97

78

98

79

99

80

100

L

BUI

101 121

102 122

103 123

104 124

105 125

106 126

107 127

108 128

109 129

110 130

111 131

112 132

113 133

114 134

115 135

116 136

117 137

118 138

119 139

120 140

141

161

181

142

162

182

143

163

183

144

164

184

145

165

185

146

166

186

147

167

187

148

168

188

149

169

189

150

170

190

151

171

191

152

172

192

153

173

193

154

174

194

155

175

195

156

176

196

157

177

197

158

178

198

159

179

199

160

180

200

201 221

202 222

203 223

204 224

205 225

206 226

207 227

208 228

209 229

210 230

211 231

212 232

213 233

214 234

215 235

216 236

217 237

218 238

219 239

220 240

241 261 281

242 262 282

243 263 283

244 264 284

245 265 285

246 266 286

247 267 287

248 268 288

249 269 289

250 270 290

251 271 291

252 272 292

253 273 293

254 274 294

255 275 295

256 276 296

257 277 297

258 278 298

259 279 299

260 280 300

301 321

302 322

303 323

304 324

305 325

306 326

307 327

308 328

309 329

310 330

311 331

312 332

313 333

314 334

315 335

316 336

317 337

318 338

319 339

320 340

341 361 381

342 362 382

343 363 383

344 364 384

345 365 385

346 366 386

347 367 387

348 368 388

349 369 389

350 370 390

351 371 391

352 372 392

353 373 393

354 374 394

355 375 395

356 376 396

357 377 397

358 378 398

359 379 399

360 380 400

401 421

402 422

403 423

404 424

405 425

406 426

407 427

408 428

409 429

410 430

411 431

412 432

413 433

414 434

415 435

416 436

417 437

418 438

419 439

420 440

441 461 481

442 462 482

443 463 483

444 464 484

445 465 485

446 466 486

447 467 487

448 468 488

449 469 489

450 470 490

451 471 491

452 472 492

453 473 493

454 474 494

455 475 495

456 476 496

457 477 497

458 478 498

459 479 499

460 480 500

501 521

502 522

503 523

504 524

505 525

506 526

507 527

508 528

509 529

510 530

511 531

512 532

513 533

514 534

515 535

516 536

517 537

518 538

519 539

520 540

541 561 581

542 562 582

543 563 583

544 564 584

545 565 585

546 566 586

547 567 587

548 568 588

549 569 589

550 570 590

551 571 591

552 572 592

553 573 593

554 574 594

555 575 5S5

556 576 596

557 577 597

558 578 598

559 579 599

560 580 600

-Zip

601 621

602 622

603 623

604 624

605 625

606 626

607 627

608 628

609 629

610 630

611 631

612 632

613 633

614 634

615 635

616 636

617 637

618 638

619 633

620 640

641 661 681

642 662 682

643 663 683

644 664 684 545 665 685

646 ESS 686

647 667 687

648 668 388 S4E SS9 689 SED 670 690 351 671 691 652 672 692 652 373 693

654 S74 694 S5E S75 S95

655 676 696

657 377 697

658 878 698 S5S 679 699 66C 5S0 700

READER SERVICE

PLACE FIRST

CLASS POSTAGE

STAMP HERE

Bill

READER SERVICE PO BOX 2114 GPO NEW YORK NY 10116 USA

PLACE

FIRST

CLASS

POSTAGE

STAMP

HERE

KITE

READER SERVICE PO BOX 21 14 GPO NEW YORK NY 10116 USA

I

■bite

SUBSCRIPTIONS

For a subscription to BYTE, please complete this card. Name

USA

Canada

Mexico

□ 1 year

□ S19

□ S21

□ 2 years

□ S34

□ S3B

□ 3 years

□ S49

D S55

Address.

City

State

■ Zip.

. Country

Card No.

Expiration date

Four digits above name—Master Charge only

Signature Date

Please allow eight weeks for processing. Thank you.

□ S43 Europe (air delivery) payment enclosed

□ S35 Elsewhere (surface mail) payment enclosed

(Air mail rates available upon request)

Pleat* r«mlt In US funds drawn on a US bank. Thank you.

□ Check enclosed (Bonus: [North America only] one EXTRA issue—receive 13 issues for

the price of 12)

4121

G OB □ r

□ Bill me (North America only)

ATE

SUBSCRIPTIONS

For a subscription to BYTE, please complete this card. Name

USA

Canada Mexico

a

1 year

□ S19

□ S21

a

2 years

□ S34

□ S38

D

3 years

□ S49

D S55

Address.

City

State

-Zip.

. Country

Card No.

Expiration date.

Four digits above name—Master Charge only

Signature Date

Please allow eight weeks for processing. Thank you

□ S43 Europe (air delivery) payment enclosed

□ S35 Elsewhere (surface mail) payment enclosed

(Air mail rates available upon request)

Picas* remit In US funds drawn on a US bank. Thank you.

□ Check enclosed (Bonus: [North America only] one EXTRA issue—receive 13 issues for

the price of 12)

4121

Z Bill me (North America only)

L

Don't Miss An Issue!

Have BYTE delivered to your door.

Each month BYTE will bring you the latest in microcomputer technology.

DISCOVER and IMPLEMENT new ideas. Don't miss the original information presented in the pages of BYTE.

With BYTE you'll always be among the first to know about the important breakthroughs, worthwhile new equipment, and innovative projects in the world of computing.

CHALLENGE US to deliver the very best ideas in microcomputers and advanced technology to you. Return the attached card todayl

Subscribe to BYTE—the world's leading computer magazine.

PLACE

STAMP

HERE

KV 1 K SUBSCRIPTIONS PO Box 590 Martinsville NJ 08836 USA

PLACE

STAMP

HERE

KV 1 K SUBSCRIPTIONS PO Box 590 Martinsville NJ 08836 USA

The

Brains of Men

and Machines

by Ernest W. Kent

When the "Brains of Men and Machines" series of articles originally appeared in BYTE magazine, the response was immediate and enthusiastic. Now Ernest W. Kent has expanded his ideas about the brain into a full-length book.

As researchers begin to unravel the mysteries of the brain's chemical, electrical, and synaptic circuitry, their findings are becoming immediately applicable to advances in robotic behavior and computer design. The Brains of Men and Machines "dissects" the brain to provide new insights into computer design and artificial intelligence.

It is one of the rare books that transcends disciplinary boundaries. In it the ever increasing relationship between man and machine is freshly examined — a relationship, Professor Kent concludes, that is today being reexamined in the light of man's own neurological self-image.

... r,r, . Call TOLL FREE: 800-258-5420

Hardcover 304 pages 0rMaiiTo;

Blifl

El 1%5

Peterborough, NH 03458

ISBN #0-07-034123-0

Price $15.95

Please remit in U.S. funds or draw on a U.S. Bank

Pie

ase send D copies The Brains of Men and Machines

of

Name

Title

Company

Street

D Check D Bill V Card

en sa No Da

City

:losed ir D

State/Province

[be amount of $ Bill Master Charge

Code

Exp

te.

Add 75a per book to cover postage and handling.

m

Automated Information Management

The revolutionary new way to computerize your business quickly and economically.

Until now you have had just two choices in computerizing your business operations. You could buy an economical system with "canned" or "turnkey" software or you could have an expensive, custom-system programmed specifically for your business.

If you decide to go the economical route, you have to compromise the way you do business to conform to the standardized software you purchased.* The custom approach can yield a system which fits your needs exactly. But it is very costly, can take years to install, and in many cases, results jn a permanent, in-house software and data processing staff.

Ohio Scientific has developed a new approach: Automated Information Management.

This system allows you to replace rooms of filing cabinets with one small computer system. Your office and clerical employees can instantly file and retrieve information, generate lists, reports, labels, forms and perform computer analysis—all without any programming. This system allows you to computerize

the office functions which are most vital to your business immediately, without programming; whether it be inventory, client records, mailing lists, personnel, prospective customers, orders, quotes, jobs, material costs or accounts receivable / payables. Virtually any files of important and often-referenced information can be immediately computerized on this system.

The system uses Information Management software built on a data base manager. This concept is not new, it's been used for years on the biggest business computers. Until now it has been impractical for use by small businesses and departments of larger businesses, because it has required a computer with a large amount of disk storage capacity which typically costs $100,000 or more.

Ohio Scientific has developed.a revolutionary new line of small, fast, economical computers which store from 7 million alphabetic characters to 80 million characters "on line", and can access this information in

thousandths of a second. These new low-cost, ultra-powerful computers, combined with highly simplified and easy to use Information Management software, yield a system that can be computerizing your vital functions in days, not months, and saving you money via improved efficiency, accuracy, capacity and time.

OhioScientific Automated Information Management systems start at under $10,000, with a typical system which has the capacity of about a dozen filing cabinets costing approximately $15,000. Although Information Management should be the primary use of your system, it incorporates a general purpose computer which can also be expanded to word processing, interoffice electronic mail, payroll processing and other specialized noninformation intensive applications via canned packages or custom software.

Ohio Scientific Automated Information Management systems are sold and supported by over 350 dealers nationwide.

For more information and the name of the dealer nearest you call 1-800-321-6850.

1333 SOUTH CHILLICOTHE ROAD | AURORA, OH 44202 • [216] 831 -5600

Circle 325 on inquiry card.