How To Buy The Right Printer \^t- COMPUTB The Leading Magazine Of Home, Educational, And Recreational Computing $2.50 June 1983 Issue 37 Vol. 5, No. 6 £1.85 in UK 63379 Using Printers With The TI-99/4A And The TRS-80 Color Computer Astrostorm, Hawkmen OfDindrin, And More Ready To Run Game Programs For VIC-20, 64 Atari, Apple, And TI-99/4A Atari Player Missiles Simplified: A Tutorial Approach MusicMaster For Commodore 64 Structured BASIC For The TI-99/4A I74'i70'l63379' 06 ;uiurt;^, GcHTies, And An ig f«e«^R>lumn-Qa. Computer Happenings: C^itihe RoSd With '^oted^uthor Fred D'Ignazio See us at Booth #1146 co[miiPiH/SPRIM6 '83 Apiil 36-37. ][?S3 Gao'gio Wofld Conoriii CanUr ond Thi ATlorrfa ApparalMarT Arlnnla, Giorgho MORE THAN JUST ANonn pnnTY ncE. Says who? Says ANSI. Specifically, subcommittee X3B8 of the American National Standards Institute (ANSI) says so. The fact is all Elephant™ floppies meet or exceed the specs required to meet or exceed all their standards. But just who is "subcommittee X3B8" to issue such pronouncements? They're a group of people representing a large, well-balanced cross section of disciplines— from academia, government agencies, and the computer industry People from places like IBM, Hewlett-Packard, 3M, Lawrence Livermore Labs, The U.S. Department of Defense, Honeywell and The Association of Com- puter Programmers and Analysts. In short, it's a bunch of high-caliber nitpickers whose mission, it seems, in order to make better disks for consumers, is olso to make life miserable for everyone in the disk-making business. How? By gathering together periodically (often, one suspects, under the full moon) to concoct more and more rules to increase the quality of flexible disks. Their most recent rule book runs over 20 single- spaced pages— listing, and insisting upon— hundreds upon hundreds of standards a disk must meet in order to be blessed by ANSI. (And thereby be taken seriously by people who take disks seriously.) In fact, if you'd like a copy of this formidable docu- ment, for free, just let us know and we'll send you one. Because once you know what it takes to make an Elephant for ANSI . . . We think you'll want us to make some Elephants for you. ELEPHANl HEJWYDUTYnSKS. For a free poster-size portrait of our powerful pachyderm, please write us. Distributed Exclusively by Leading Edge Products, Inc., 225 Turnpike Street, Canton, Massachusetts 02021 Call: toll-free 1-800-343-6833; or in Massachusetts call collect (617) 828-8150. Telex 951-624. FOR YOUR COMMODORE WORDPROCESSING NEEDS INVEST IN THE BEST iifesslona rfessiooai puus rtus WORDPRO PLUS. IN A ClASS BY ITSELF. When choosing a Word Processor (or your Commodore'" computer, there's no reason to settle tor anything but the best — in a worrf. . .WordPro'". With over 30,000 happy clients churning out letters and documents all over the world, the WordPro Plus'" Series is unquestionably the #1 selling soft- ware package on Commodore computers! So when you choose WordPro, you know you're Investing in a trial-tested program that's a real winner. And WordPro is NOW available for your Commodore 64" computer— at prices starting as low as 389.95, Designed for the user who has no computer or word processing experience whatsoever. WordPro Plus brings a new dimension to the term "usef- friendly." More than just easy to use, WordPro will turn your Commodore computer into a sophisticated time saving word processing tool — loaded with the same inventory of features found in systems costing much, much more. Our nationwide team of over 600 Professional Soflwara/Commodofe com- puter dealers will help you choose the WordPro Plus system that is best for your needs. Our full-service dealers have been set up to provide strong customer support. In addition to helping you choose the right system, many Professional Software dealers also offer WordPro Plus training and system installation. Professional Software offers a complete spectrum of WordPro word process- ing software for Commodore computers ranging from the Commodore 64 to the more business oriented 8000/9000 series computers. And WordPro 4 Plus and 5 Plus also interact with our database management systems includ- ing InfoPro and The Administrator. So whatever your Word Processing needs, there's a WordPro system that's right for you. WordPro" and WordPro Plus" are Irademarks of Professional Software Inc The WordPro Plus Series was designed and written by Steve Punter ot Pro Micro Software Ltd. Commodore'" and the Commodore 84" are trademarks of Commodore Electronics. Inc. Dealer inquiries invited. Wor(«Vo3nu»/«4" i Invest in the best. . . WordPro Plus. In a class by itself. Call us today for the name of the WordPro Plus dealer nearest you. Professional Software Inc. 51 FrefTiont Street Needham, MA 02194 (617)444-5224 Telex: 951579 SPINNAKER'S UNE OF EARLY LEARNING GAMES ISGR0IMNG AS EAST AS YOUR CHILD'S MIND. Watching your kids grow up is a lot of fun. But making sure their minds grow as fast as their bodies is even more rewarding. That's where we can help. With a growing line of Early Learning Programs that are not only lots of fun to play but also educational. Some of the games you see on these two pages help exercise your child's creativity. Others help improve vocabulary and spelling skills. While others improve your child's writing and reading abilities. And all of them help your child understand how to use the computer. So if you're looking for computer programs that do more than just "babysit" for your kids, read on. You'll find that our Early Learning Programs are not only compatible with Applef Atari® IBM" and Connmodore 64™ computers, but also with kids who like to have fun. HEY DIDDLE DIDDLE™ Poetry in motion. Ages 3 to 10. Kids love rhymes. And since HEY DIDDLE DIDDLE features 30 classic rhymes with full color graphics and the neatest computer music you've ever heard, it makes rhyme games more fun than ever before. Plus, it makes it fun for kids to read, helps them understand how words and rhymes create poetry and lets them take fragmented thoughts and rearrange them to form coherent verse. Apple. IBM and Atari are registerai trademarks of Apple Computer. Inc.. International Business Machines Corp. and Atari. Inc. respectively. Commodore 64 is a trademark of Commodore Electronics limited. The story of STORY MACHINE™ Ages 5 to 9. STORY MACHINE is tike a storybook come tx) life. Using the key- board, your children write their own fun little stories. The computer then takes what they've written and animates their story on the screen, com- plete with full color graphics and sound. STORY MACHINE helps your children learn to write correctly, become familiar with the keyboard, and lets them have fun exercising their creativity at the same time. KINDERC0MP7" Numbers, shapes, letters, words and drawings make fun. Ages 3 to 8. KINDERCOMP is a game that allows very young children to start learning on the computer It's a collection of learning exercises that ask your children to match shapes and letters, write their names, draw pictures, or fill in missing numbers. And KINDER- COMP will delight kids with color- ful rewards, as the screen comes to life when correct answers are given. As a parent, you can enjoy the fact that your children are having fun while improving their reading readiness and counting skills. PACEMAKER™ makes faces fun. Ages 4 to 12. PACEMAKER lets chil- dren create their own funny faces on the screen. Once a face is completed, your children will giggle with delight as they make it do all kinds of neat things: wink, smile, wiggle its ears, or whatever their imagination desires. Plus, PACEMAKER helps children become com- fortable with computer fundamentals such as: menus, cursors, the return key. the space bar. simple programs, and graphics. PACEMAKER won't make parents frown because their children will have fun making friends with the computer SPtNTMKnff © 1983. Spinnaker Software Corp. All rights reserved, V\fe make learning fun. A -^ ^^°^^^rani'^''^^ ^r even ^«^P" oO"" June 1983 Vol. 5, No. 6 FEATURES 36 HowToBuyThe Right Printer Charles Brannon 44 The New, Low-Cost Printers KothyYakal 61 Using A Printer With The TI-99/4A C.Regena 63 Commodore ToASCII For Printers Thomas Henty 70 Connecting A Printer To The TRS-80 Color Computer Ottis Cowper EDUCATION AND RECREATION 72 Astrostorm Peter Lear 86 The Hawkmen Of Dindrin Estebon V.Aguilar. Jr. 102 Bee Trap Rotiert L, Lykins 112 Memorv Trainer Harvey B. Herman 122 MusicMoster For The Commodore 64 Chris Metcaif and lylarcSugiyama REVIEWS 134 Commodore 64 Programmer's Reference Guide Anu M, Gupta 136 The Printographer Graphics Printer Package For The Apple Richard Cornelius 137 Marathon For Atari Mike Kinnamon 138 Disk Data Manager For VIC And 64 Col Hunter 140 Ghost Encounters For Atari Tina Halcomb COLUMNS AND DEPARTMENTS 6 The Editor's Notes Robert Lock 10 Readers' Feedback The Editors and Readers of COMPUTE! 18 Computers and Society: Androids And Robots David D. Thorn burg 24 The Beginner's Page Richard Mansfield 26 Questions Beginners Ask Tom R. Halfhill 30 On The Road With Fred DTgnazio: Twilight Of The Computer Hacker Fred D'Ignazio 150 Friends Of The Turtle: HES Turtle Graphics II David D. Thornburg 152 The World Inside The Computer: Turning Logo Upside Down Fred D'Ignazio 160 Learning With Computers Glenn M, Kleiman 164 Micros With The Handicapped: Developing A Communications Program Susan Semoncil^and C. Marshall Curtis 182 Programming The Tl: Translating Programs Info Tl BASIC C.Regena 214 Insight: Atari Biil Wilkinson 250 MachineLanguage:NumericOutput, Part II Jim Butterfield THE JOURNAL 167 168 175 180 •185 188 -194 200 204 206 -210 -213 216 219 223 224 226 234 235 238 242 246 254 -256 -260 272 144 148 274 279 294 295 304 Data Searcher Jerry Sturdivant Apple Shape Generator J.F.Johnson Atari Player/Missile Graphics Simplified Staffon Sandberg Slow List On The VIC-20 Ken Bowd VIC, 64, And PET Supermon Questions And Answers Jim Butterfield An Interesting Fragment Of Code Chris Crawford Commodore64Video- A Guided Tour, Part V Jim Butterfield Easy VIC Machine Language Saves Poul Christensen Tl Structured BASIC Steven M. Ruhl Atari Formats Sheldon Leemon Joysticks For The Commodore 64 Michael A Tyborski L)nNEWForTheVICAnd64 Jim Wilcox Machine Language Saver JohnO. Battle Automatic Atari DATA Statements Richard Dorfner Atari Fast Shuffle James E. Korenthat VIC Contractor Peter Lear Custom Characters On Atari Charles Delp Sinclair/Timex Screen Splitter Harold Miller VIC Power Spirals Bruce Jordan Using The Atari Timer Stephen Levy Visiting The VlC-20 Video, Part II Jim Butterfield PET Reiative File Field Separator T AZucol Atari Reset Run Thomas A Marshall Soft-16For Commodore 64 Douglas D. Nicoll Minefield Seonlgo Relocation Calculator Linton Chostain A Beginner's Guide To Typing in Programs How To Type COMPUTEi's Programs CAPUTE! Modifications Or Corrections To Previous Articles News & Products Calendar Product Mart Advertisers Index NOTE: See page 148 before typing in progroms. GUIDE TO ARTICLES AND PROGRAMS Tl PA//64 C V/ATWAP V/AT/64 V/AT/C 64A//P/ATffl/AP 64 64 AP AT V/64 AT V/P Tl AT PMM AP AT V V/64/P 64 V Tl AT 64 V/64 V/64 AT AT V AT ST V AT V P AT 64 V/64/AP/P C AP Apple. AT Atari, P PET/ CBM,V VIC-20, OOSI.C Radio Shack Color Com- puter, 64 Commodore 64, S/T Sinciair ZX-81, Tl Texas Instruments, */\ll or several oftheabove. COMPUTE! Ttie Journal for Progressive Computing (USPS: 537250) is published 12 times e.icli year by Small System SemcfS, Inc., P.O. Box 5406, Greensboro, NC 27403 USA. Phone; (919[275-9H0y. Edilorijl Offices are located at 505 Edwardiii Drive, Greensboro, NC 27409. Domestic Subscriptions: 12 issues. S20.00. Send subscription orders or change of address (P.O. form 3S79) to Circulation Dept., COMPUTEI Magazine, P.O. Bolt 5406, Greensboro, NC 27403. Second class postage paid at Greensboro, NC 27403 and additional mailing offices. Enhre contents copyright © 1983 by Small System Services, inc. All rights reserved. ISSN 0194-357X. TOLL FREE Subscription Order Line 800-334-0868 In NC 919-275-9S0« EDITORS NOTES COMPUTE! Publications A Subsidiary Of American Broadcasting Companies, Inc. bbc As many of you arc aware by now, wc have become the eleventh operating division of ABC Publishing. What it means initially is that we'll have available resources and support that we've never enjoyed before as an independent company. In addition to the general strengths that our alliance with ABC pro- vides, we'll have senior manage- ment expertise and skilled busi- ness support of a type that we've never had available. We're all quite pleased with this mutual blending of the styles and strengths of two healthy com- panies, one old, one young, but btith very much committed to the future of our industrv. Best of all, COMPUTE! Publi- cations will continue to operate as a separate division, without internal changes, and from exactly the same perspective of superior quality and leadership in personal, consumer pub- lishing. 1 even expect to find more time for planning, re- search, and new product direc- tion and development. It seems appropriate, on the occasion of this announcement, to recount the current growth of COMPUTE! Publications. Our COMPUTE! Books Division will have over 16 titles in print bv the end of July; COMPUTE!'^ Fust Book of VIC is currently in its sixth printing. COMPUTE!'s Gazette for Commodore VlC-20 and 64 computers is promiering this month with an initial press run of 175,000 copies. An in- credible feat given that COM- PUTE! broke 100,000 in October of last year. Finally, our flagship, COMPUTE! Magazine, has achieved the significant 300,000 barrier. Our press run for this issue is 315,000. Need 1 add, "and growing..."? The latest round of price cutting has reached a level defying the most aggressive pre- dictions. Prices have dropped so fast that Texas Instruments was caught while delaying the planned introduction of the TI- 99/2. By the time the 12 series was scheduled to be introduced at $99, market moves had brought the price of the /4 down to S99. The Atari 1200, recently announced at the $1000 le\'el, has rapidly dropped to the $600-700 range; the 400 is now below SI 50. And then there's Commodore, with the VlC-20 below $90 in many areas, and the 64 at S399, or $299, if you're able to take advantage of the trade-in offer {where you trade in your old computer or video game com- puter and receive a $100 rebate). What's in the wind at Com- modore? We've heard rumors of pending change with the new President of North American Operations bringing in selected new key personnel. We've also heard that some existing, previ- ously key personnel are looking around for other opportunities in the industry. Is another fa- mous Commodore shake-up on the way? Stay tuned, we'll try to keep you posted. In another vein, the ac- knowledgment that software is a critical factor in the marketplace seems to be gaining strength on all manufacturers' strateg}- plan- ning calendars. Tl seems to be making progress with their licensing program for in-house sale of out-of-house developed programs. Commodore has established a new division to develop and promote the sale of Commodore software. And through it all, both established and newly formed software houses are pursuing the growth of the industrv. Next month: A super-ior special theme issue, our third on Games. 6 COMPUTE! June 1983 '*iLi; ,, An Ocean Apart is^IjfST?^, '■^wm ' V':M'- ,:^m Pacific Coast Software Corporatio The leading manufacturer of Commodore 64; software • Word Processing ^--^-nS' • Data Base Systems -^--.^-.-li • Home and Business Accounting f "^-^^ • Educational •Entertainment ^^ i • PCS/6480 Column Board —which contains resident executive driver that interfaces word processing, data base and spread sheet program modules, j ^■fSstBtim; FOR FURTHER INFORMATION CONTACTTHE DISTRIBUTOR NEAREST YOU TODAY! r^^ SOUTHEAST -(615) 690-6966 mm CANADA -(416) 366-6192 ^^ UNITED KINGDOM - 01-900-0999, TELEX 2860 . 'Mm Dealer Inquiries Encouraged PACIFIC COAST SOFTWARE COR •];fiii[iik'i 3220 South Brea Canyon Road, Diamond Bar, California 91765 (714)594-8210 ■£ Iv^i^-pSyi^S^^^fjgr^^^^r': :.?,--:.-!!fC^jj^ CDmmodore (y1 is a registered trademark of Commodore [acctronics, Ltd. - ■-'■.«-irjv -fr i^ .vi;.-,':;,^-5~Tj^- Visi* -•is'^sytt Publ lihei/Editof -Jn-Ch ie( PubliS^ef'5 Assistonf Robert C. Lock Alices. Wolfe Senior Editor Monagir^g Editor AssJSlonI Managing Edilor Production Editor Features Editor Technical Edilor Piogram Editor A$sistanJ Editor AssisJanI FeoturesEcfttof Assistant Copy Editor Editorial AssisI ant Progiomming Assistonfs Administrative Assistants Copy Assistants Associcris Editors Contributing Editor Richof d Mansfleld Kathleen E. Nrtortir^ek Tony Roberts Gait Walker Tom R, Halfhiill Ottis R, Cowper Ctiorles Brannon DanCarmichael John BiocWord Juanrta Lewis KathvYokol Patrick PQrtish G^-egg Peele Jorkothan Byrd Vicki Jennirigs Lourq MacFodden Becky Ha ij SorotiJohnstcxi Lindo Shaw Jim Butterffeid, Toronto. Corioda Horvey Herrnan, Greensboro, NC Fred D'lgnozia 2117 Carter Rd-SW, Roanoke, VA 24015 David Thornburg » Elox13l7,LO5AJtos.CA94022 Bill Wilkinson COMPUTEI's BookClfviskjn Editor AssislanI Editor Adm I ni strati ve Asaston I Artist Orson Scott Card Steptwn Levy Cofoi Eddy Jon ice Fary M Direclor/Production Manager Georgio PapQdopoulos AssI stent Artists Typesetting Illustrator Promot ion Assi slan t Production Ass;stant ImraSwoln De Potter Jean Hervdrix Terry Cash Harry Blair ToddHeimarck OoiRees Associate Publisher/ National Advertising Soles Manager Advertising Coord inortor Advertising Accounts Soles Asist ant AndyMeehon PottiWiJiioms Bonnie Valentino Rosemarie Daws Opera tioni'Custom er Service Manoger Assistants Dealer Coordinator Assistants Shipping gc Receiving Carol Lock Potty Jones Shonnon h/teyer Fran Lyons Goil Jones Shorcn Minor Ch^is^ne Gordon CossorxJiro Robinson MawSprogue DoiOfhyBogan Chrjs Patty Rhonda Savage LisaFtoharty Cof ol Dickerson Jim CDwoj"d lorry O'Connor Chris Cain Jackfs^Connel! Data Processing Monoger Assistant Leon 5tokes Joan Compton Accountirtg Monoger Ekxskkeeper Accounhng Asstetants Assistants W. Jerry Doy Ellen Day Undo ryli Her Doris Hall Ruth Granger Anna Harris Em I lie Covil Anne Ferguson Robert C. Lock President W. Jerry Day, Vice President ond Comptroller E. Norman Graham. Vico-President and General Counsel Kathleen E, fylorfinek Assistant To The President Sonja Whitesell. Executive Assistant Coming In July Special Games Issue Featuring Some Of The Finest Computer Games Ever Publistied: RATS!, Speedski, Time Bomb, Castle Quest, Roadblock, Gobiins, And The Fortress OfAdnill Pius: Programming The Ideal Game The Game POKEr How To Write Your Own Adventure Game Small System Services, Inc publishes COMPt/riiBooks Telephone: 919-275-9809 Cofpornle oNiee: 505 Edwa:c3ia Drive, Gisensboro, NC 274OT Ui* Moiling address: COMPUTE! Post Office Boi M06 Greeniboro. NC S'aOS USA Subscription Information COMPUTE! Circulation Dept. P.O. Box 5406 Greensboro, NC 27403 TOLL FREE Subscription Order Line 800 334-0868 lnNC919-275-9BD9 COMPUTE! Subscription Rates (12 issue Year): us (one vr.) S20 Air (twoyrs,)S36 (three yrs,) S54 Canada and Foreign Surface Mail $25 Europe, Australio S38 Middle East, Central Americo and Nortti Africo S46 Soutti America, South Africa, For East S68 Advertising Sales In British) Columbia, Canada, Alaska or Hawaii coll 408-354-5553, Elsewtiere in Canada or outside North America call 919-275-9809, The Gittelman Compony' /Ai Dalton J 4- Ruth Williams ^ ^_^^^617-451-0822 / The Gittelman'*' r^ — 'Compony 7 V Sharon Brodit L -;Joe Portei / ■'^ '215-646-57ui,, NY Metro 212 -567-6 '1/ COMPUTE! Home Ofltce Andy f^eehan Notional Advertising Soles Monager 9W-27S-98D9 Phoebe Thompson and Associates 101 Ctiurch Streei Suite 13 Los Galos, CA 95030 PHOEBE THOMPSON Phoebe Thoinpson and Associates 2556 Via Tejon Polos Verdes Estates, CA 90274 JOANN SULLIVAN OB & Associates P,0, Box 335 Libertyville, IL 60048 GORDON BENSON The Gittelman Company The Gittelman Company Statler Office Building Suite 518 20 Providence Street Boston, MA 02116 AL DALTON RUTH WILLIAMS Summit Office Center 7266 Summit Avenue Foil Wasliington, PA 19034 SHARON BRODIE JOE PORTER COIMPUTE! Home Office 505 Edwardio Drive Greensboro, NC 27409 HARRY BLAIR Southeastern Soles r^ecresentative Address all advertising materials to: Potti Williams Adveilising Production Coordinator COMPUTE! Magazine 505 Edwordio Drive Greensboro, NC 27409 Auttiors of manuscripts warrant ttiot oil materiols submiMed to COMPUTE! are original materia is witti full ownership rights resident in said outhors. By submitting articles to COMPUTE!, authors acknowledge that such materials, upon occeptonce for publicotion, become the exclusive property of Small System Ser- vices, Inc, No porlion of this magazine may be reproduced in any form without written permission from the publisher Entire contents copyright .» 1983, Smell System Services, Inc. Rights to progroms developed end submitted by outhors are explained in our author contract Unsolicited materials not accepted for publi- cation in COMPUTE! will be returned if outhor provides a self-oddressed, stamped envelope. Programs (on tope or disk) must accompany each submission. Printed listings ore optional, but helpful. Articles shou Id be furnished as typed copy (upper- and lowercase, piease) with double spacing. Each page of your article should bear the title of the article, date ona name of the author. COfvlPUTE! assumes no liobility for errors in articles or odvertisements. Opinions expressed by authors ore not necessarily those of COMPUTE!. per. C6M, VTG- 20 ard Conirrodwe 64 oie trademarks ot Con-imodo*e Busirwss MocPiirHis, Inc, anojai COfrirrvoOixo Eoctionics Liinitec ttadro Shock Color Compulei 15 o fiodemaik ot rofKJy, Inc 8 COMPUTB June 1983 ^r commodore CBM computer AN INFORMATION MANAGEMENT SYSTEM FOR YOUR COMMODORE COMPUTER InfoPro is a menu driven and interactive "information management" system for the Commodore 8032 computer, InfoPro uses "friendly" screen prompts that "guide" you from function to function. This makes InfoPro unusually easy to learn and just as easy to operate. For Mailing List applications InfoPro can print up to S labels across and even has a built in "structure" with fields already pre-set. This structure can easily be changed to fit many other types of office jobs. Another extremely powerful feature of InfoPro is Super Scan. The Super Scan feature acts like an "electronic filing cabinet" and pro- vides the user with almost instantaneous access to the data stored in a file. The powerful Report Generator allow-s you to "select" infor- mation for printing based on up to 5 different parameters or criteria and to perform various math functions. Another powerful and indispensable feature is InfoPro's ability to interact with the WordPro family of word processing programs. This provides the user with a "link" from the area of data information WordPro and InfoPro are registered trademarks management to the area of word processing, allowing the user to manipulate, sort, and select data by certain criteria, which can then be inserted into "personalized" letters, documents, overdue notices, etc. InfoPro will also allow you to ADD, DELETE or CHANGE your information "fields" any time you wish. This means that as your business changes, InfoPro has the flexibility to change with it. As with all Professional Software products, InfoPro comes complete with a professionally written and fully-tested user oriented manual. InfoPro also includes a program ROM, and InfoPro System Diskette . Start managing your information today. Call us today for the name of the Professional Software dealer nearest you. Professional Software Inc. 51 Fremont Street Needham, MA 02194 Tel: (617) 444-5224 Telex: 951579 of Professional Software READERS' FEEDBACK The Editors and Readers of COMPUTE! Copying VIC/64 DOS Wedge I've tried to save the DOS support program from the test/demo diskette supplied with the VIC 1541 disk drive to one of my ovim. I also saved the loader. Both SAVE and VERIFY correctly, but when I run the loader my Commodoro-64 spits back SYNTAX ERROR IN 52940! Why does it do this, and if possible, hou' do 1 save it to another disk? Erik Bard Vow cannol SAVE or LOAD tlicse programs as you would a BASIC program. This is the reason you are gettiug SYNTAX ERRORs. The DOS 5.1 program is in machine language, not BASIC. Madiiue language programs have to he saved a)id loaded in a special way that specifies -where thei/ ca)ne from in memory. If you wish to copy tins program to your own disk, here is the procedure: 1. First, you'll need a machine language nwnitor up and running in your 64. Supennon-64 (COM- PUTE!, January 19S3) is a good monhor to use for this purpose. Any monitor or assembler will do as long as it does not reside in the $CCOO • $CFFF range (decimal 52224 - 53247). 2. While running from loitliin the monitor, LOAD the DOS 5.1 program into memorij by entering L "DOS 5.1", 08.' 3. Place the diskette you wish to sa~oe the program to i}ito the disk drive, a)ui save the prograni by entering S "DOS 5. 1 ",08,CC00,CF5A. 4. Place the Coinnuniore test.^deim-> diskette back into the disk drive, and from BASIC, LOAD the 64 Wedge loader into memory. 5. Place your neio diskette back into the disk drive, and save the BASIC prograiu in the )Hvnud manner (i.e.: SAVE '^-64 WEDGE", 8). 6. Now to nu! your )iew copy of tlie DOS 5. 1 program, simply load the 64 WEDGE i}ito your system, and RUN it as usual. Epson Printer's Groftrox Several readers have inquired about the review of the Craftrax-SO, published in the December 1982 issue of COMPUTE!. Specifically, they ivanl to kinno if it is possible to redefi)U' the MX-SO codes to approximate those of the Ceji Ironies 737. That way, software -written 10 COMPUTE! June 1983 for the 737 could run without modification. The Epson MX-80 with Graftrax-80 can redefine its escape codes. These are printer functions controlled by sendi)ig the escape character, CHR$(27), and then a letter such as "£" for Enhaitced printing. There are many other functions, however, that are controlled by sending an ASCII value less than 32 (a control charac- ter), such as CITR$(14), which signals double-wide characters. These functions cainiot be redefined. Current MX-80 printers are bei)ig shipped with Graftrax Plus. While Graftrax Plus ijnproivs on Graflrax-80 by adding underlining, super- ami sub- scripting, and faster graphics, some functions ofGraf- trax-SO were dropped to make room for the enhance- me)!ts. Epson feels that those functions were not used very often ain/way. Specifically, these functions do not carry over from Graftrn.x-SO to Graftrax Plus: TRS-80 graphics, Vertical Tab, aiui escape code redefinition. You can find out which version you ha-oebyseiuiing the printer a CHRS(129) with sojueihing like LPRINT CHRS(129). If you get a small graphic box, you'x'c got Graftra.x-SO. If you don't know whether you have any kind of Graftrax, send the pri)iter: LPRINT CHRS(27);"4 Hello there!" If you get italics, you've got Graftrax. Rounding Numbers In using the simple program below, I encountered a (possible) bug in Applesoft's handling of vari- ables. After the program is RUN, and an input of 3,4,5 is given (a known right triangle), 1 get an output of "NO". When I PRINT X and D, I get 5 and 5, respectively. But when I PRINT X = D, I get a response of zero, meaning "false." Is this a known error, or is this a bug in my program? Ken Carpenter 1 PRINT"THIS PROGRAM WILL DETERMINE THE " 2 PRINT "PYTHAGOREAN TRIPLE" 3 PRINT "INPUT 3 NUMBERS" 10 INPUT A,B,D 40 X=SQR( (A*A)+(B*B) ) 50 IF D=X THEN INVERSE : PRINT "YES" : GOTO 70 55 INVERSE 60 PRINT "NO" 70 NORMAL: GOTO 1 The problem that you speak of here is conunon to most forms of BASIC and has to do zvith the manner in -which LAST Night, CompuServe TurnedThis Computer Into ATravel Agent For Jennie, A Stock Analyst For Ralph, And Now, Irs Sending Herbie To Another Galaxy. NO MATTER WHICH COMPUTER YOU OWN, WE'LL HELP YOU GET THE MOST OUT OF IT. If you've got places to go, CompuServe can save you time and money getting there. Just access the Official Airline Guide Electronic Edition— for current fligfit schieduies and fares. Make reservations througfi our on-line travel sendee. Even charter a yacht through "Worldwide Exchange." If your money's in the market, CompuServe offers a wealth of prestigious financial data bases. Access Value Line, or Standard and Poor's. Get the latest information on 40,000 stocks, bonds or commodities. Then, consult experts like IDS or Heinold Commodities. All on line with CompuSeAfe. Or if, like Llerbie, intergalactic gamesmanship is your thing, enjoy the best in fantasy, adventure, and space games. Like MegaWars, the ultimate computer conflict To get .all this and more, you'll need a computer, a modem and CompuServe. CompuServe connects with almost any personal computer, terminal, or communicating word processor To receive an illustrated guide to CompuServe and learn how you can subscribe, contact or call: CompuServe Consumer Inlormalion Service 2180 Wilson Road. Columbus, Ohio 43228 800-848-8199 In Ohio, call 614-457-8650 An H&R Block Company r>^T^:r^:.7~ Look what for your VIC 20. W / > past action. Complex strategies,, ~^n Interesting cliaracters. Supe- rior sound effects. Multiple levels-, of play These are the things you^wanf from your VIC 20™ ^ ' ^^ They're also the things you get Txom Tronix- From the people whQ_ brought you Swarm!, Sidewinder and Galactic Blitz. And now, there's more. Now Tronix brings you the same rewarding rapid-fire excitement in / three brand-new game cartridgesT^" Each one is something dif- ferent. Something new, Bu^ they alL, have one thing in commorTW-^^/^ They're all designed to bring out the best in your VIC 20. / ' You shouldn't settle for an^^f- Ihiog les^u^^^ , , .^7>^ we have in store Your helicopter gun- shifD hovers over the enemy's military bases and missile emplace- ments. Your mission is to destroy them. But as the sky fills with smart bombs and anti-aircraft fire, there's , less and less room for a wrong ■ - "r^ move j (Suggested retail $39.95) Corey Ostman.. Deep in the earth, a fortune awaits. But the dark passageways are filled with peril as well as profit. Runaway boxcars. Crashing boulders. A claim jumper with murder in his eyes. Be carefuL But be quick— oxygen is in ' SUpplyJ (Suggested retail $39,95) ^295 South La Cienega Blvd.. Inglewood, CA 90301 ronix games in your nearest store. If you can't find ttiem there, write to/j '.'IC ?.Q"' IS r! !rado!riark otCo'iTnodore Electronics Ltil computers handle real numbers. A very small calcnlatioii error will occur in some instances. In your exmupk, the uujiiber that is calculated for X on the Apple is slightly more than 5 (5.000000002, actually). PRINT X-D to see this difference after R UNning the program . Before the Apple prints a value for X, it rounds this mmiber to 9 digits and drops trailing zeroes so that 5.00000000 appears on your screen as 5. Internally, the Apple stores this number with greater precision (Recall that X was not equal to D in your example). A ivay to get around this problem is to conivrt numeric values to strings ami then compare the strings. In this ivay, the small calculation error is not seen. In your program, line 50 would then read: IF STR$(D) = STRS(X) THEN INVERSE:PRINT"YES": GOTO 70 Promqueen Review: A Manufacturer's Reply The following conu)ients are excerpted from a letter received from Stephen Bolger, Coieral Manager of Gloucester Computer Bus: We read Ihe review by Mr. Herman in January's COMPUTEI with disappointment. Mr. Herman evidently did not consider the Promqueen's merits as a de\'elopment system/ he merely considered it as an EPROM programmer. When a manufacturer places his product in the hands of a publication for review he places his trust as well that the product, if reviewed, be reviewed on the basis of its advertizing claims. Unfortunately, the review which eventuated does not appear to address, much less niention the product's claim to be a microprocessor development system. Such sys- tems usually start at S5000 and go up steeply from there. The Promqueen exists to give ultra low cost access to a microprocessor development system. Stephen R. Bolger General Manager Gloucester Computer Bus COMPUTE! eiuieavors to provide objective revirws. While we regret that Mr. Bolger feels that his product urns not thoroughly described, the review was funda- moitally positive and, we believe, balanced. Further, we cannot agree that the Promqueen is the equivalent of a $5000 development system, and would have done our readers and the maiuifacturer a disservice if we had chosen to review it iit that light. An Answer To The Restless Atari ROM Referring to the letter from Joe Cocuzzo in the March 1983 issue about the "Restless Atari ROM," I have had a similar problem with my Atari 800. After many trips to my authorized service center W COMPUTE! June 1983 the problem was still present. I believe I know what the problem is. Placing cartridges in and out of the machine flexes the mother board. As this board flexes, the chips on it work loose in their sockets. Evenhially intermittent failures can occur. When the machine starts to misbehave, I reseat all of the chips. This corrects the problem for about six months, depending on how often cartridges are inserted. David Fehr Apple POKES On the Apple, POKE 1011,0 re-boots on your disk when CTRL-RESET is pushed. This can be very inconvenient later on when you are in the middle of a program. Is there another POKE statement to get out of that? A. Welch If a value of 157 is POKEd into location lOTl, this feature ivill be disabled. This was determined by PEEK- ing the above location after powering up the Apple. PEEKing a particular location before and after a program is RUN 'would 'work o)i all computers xohich alloic PEEKing and POKEing. This is a useful zvay to deter- nii>u' the default ()wrmal) status of important addresses. The New Timex 2000 In vour article on the "New Home Comptiters" (March 1983), you wrote about the upcoming Timex/Sinclair 2000 computer. I own the ZX-81 with T/S 1000 software and ZX printer, if I bought the T/S 2000, would I be able to use my T/S 1000 software and ZX printer with it? Adam Schaffer Sources at both Tiniex and Sinclair say that softivare loritten for the T/S 1000 'will, in most cases, run on the TIS 2000. Hozvei'er, there could be a problem lohen transferring soft'warefrom the T/S 1000 to the T/S 2000. Al this time, the Timex people intend to provide a stringy-floppy disk drive for the T/S 2000. They are )}ot \/et definite about 'cohether there 'will be a cassette player. E'oen if a cassette is marketed for the T/S 2000, there is still some question concerning the compatibility of the tivo units. It's possible that a cassette for the T/S 2000 -would load at a different speed than the T/S 1000 cassette, thereby preventing softivare transfer. But these peripherals are still in the planning stage, and -we'll need to ivait to hear more from Tinwx/Siiuiair. hloweivr, the ZX printer is expected to be fully compatible with both machhies. nnJiii lalsano; ,uper-— -^^e U-S- V^^ ^^ ' <;''' ,n EVERV WAV litiesln"' 1816)254- Lookfor l^M^u . .:^yiV^tfS&/^ ^^^o^^lH?*^ f OR PWS' Printing Atari Character Sets Many of your game programs use a redefined character set, but access it by means of a POKE. What a headache! Is there any way on the 800 to change the ATASCII character set so that it can be accessed by PRINT statements? Howard Fishman It is possible to use strings to hold a redefined character set. We prefer the POKE method, hoiuevcr, because it is the easier one to type into the computer. Using strings would require the entry of quite long strings, filled loiih strange characters. Genealogy Recently I attended my first Computer Genealogy meeting and saw the program "Roots," used in building a family tree. Unfortunately, this pro- gram is not available for Commodore PETs. I'm looking for a comparable program (price and capability-wise) that will run on a 32K PET. Any suggestions? By the way, I noticed Genealogy (tracing your family back for generations) and Refunding (mailing in box tops and labels for cash, which I do) were two items not mentioned in the De- cember '82 issue "How COMPUTE! Readers Use Their Computers" (pg. 30). So there's two more to add to that list! Rita M. Thrasher Tl ISIonltor Connection Can you help me? Our school has recently pur- chased 8 Texas Instruments TI-99/4A microcom- puters. Among the 8 donated black and white television sets was a Hitachi monitor used with an Apple computer. Can 1 hook up the Hitachi monitor to the TI? If so, how? George S. Ruff TI-99/4A Video Connector 1 2 o\ 4 Ground ""^ / Video or the back side of an easily-obtainable fiz^e-pin DIN plug which plugs into the connector. Use shielded cable with the shielding braid connected to the GROUND pin. For the other end of the cable use whatever type of plug mates with your monitor's input jack. Atari 400 Upgrade In your December 1982, Issue 31, someone in- quired about the flaws in the operating system of the 400/800 computers. I have an Atari 400 with the old operating system. Is there any way for me to get the new OS (revision B)? or is there any way to upgrade the existing ROM? Rocky Boniello No officially supported OS upgrade is offered by Atari, but you might contact your local Atari Service Repre- sentative. The ROMs are not on a removable board in your 400, so it is even harder to upgrade. Understandable POKEs I have only had my Commodore 64 for a month, and I'm already becoming a fanatic. I have a problem which I'm sure others have, and I also would like to propose a solution. Most BASIC language programs can be fol- lowed with little difficulty, except for the POKE and PEEK statements. Without knowledge of each computer, one cannot follow or use the pro- grams submitted in your magazine. My solution is to use REM statements with each POKE or PEEK. For example, if I submitted a Commodore 64 program and had a statement such as 110 POKE 53281,1 many would not understand it. However, 110 POKE 53281, 1:REM**SET BACKGROUND COLOR TO WHITE** would assist people, since they could then use the appropriate commands or memory location to accomplish this on their computer! Don Hollingsworth This sounds tike an excellent idea. Some complicated programs use POKEs and PEEKs too often for this to be practical. Hoivever, many programs PEEK or POKE only a few times and such REM statements would be of real value to oiuners of other computers. Although the Tl video output is a color signal, an ac- ceptable black and white monitor picture can be obtained by taking the two signals shoivn in the figure below to the monitor input. The figure shows the video connector as you would see it facing the back panel of the T1-99/4A, 16 COMPUn! June 1983 COMPUTE! welcomes questions, comments, or solutions to issues raised in this column. Write to: Readers' Feedback, COMPUTE! Magazine, P.O. Box 5406, Greensboro, NC 27403. COMPUTE! reserves the right to edit or abridge published letters. O Our newest magazine, COMPUTERS Gazette for Commodore, is written for the beginning consumer of personal computing. Each monthly issue will bring you interesting features, exciting news, intriguing new products, and more. You'll find software news, best seller rankings in the recreational and educa- tional areas, and interviews, overviews, and industry views. Tutorials for beginners, advanced games for non-programmers, and intro- ductory help for fledgling computer users. And best of all you'll stiil find COMPUTE!, our monthly resource and appli- cations magazine for intermediate and advanced users. COMPUTE.' 's Gazette for Commodore and COMPUTE!. We won't out- grow you... we'll grow with you. Use the attached post card or call Toll Free 800-334-0868 today to reserve your premiere issue of COMPUTE.' 's Gazette for Commodore. 12 monthly issues. Charter Subscription Price $15 US, $20 US in Canada, elsewhere, Air Mail, $45 US. Other than as an independent supplier of quality products regarding Commodore, VIC-20, and Commodore 64 are trademarks of the Commodore personal computer systems, COMPUTE! Publications Commodore Business Machines, Inc. . and/or Gvmmodore is in no way associated with Commodore Business Machines, Inc. Electronics Limited. Computers And Society David D Thornburg, Associate Editor Androids And Robots The rain stopped faUiii;^ as soon as he pulled his car into the parkins; lot at Polaris Astronautics. He was an hour early for his appointment , but his host had told him to come early for a plant tour. As soon as he checked in with the receptionist, he zvas greeted bi/ his "tour guide." "Hello, Dr. Calder. We at Polaris are glad i/ou could "oisit today. I will conduct you on a guided tour prior to your meeting with Dr. Clevis in the propulsion laboratory. My name is BO-3, hut nutsl people call me Bothrei/. I have been trained to recognize your voice, so if you have any questions, please don't hesitate to ask me to help you." jon Calder looked at Bothrey as he (or it) wandered (or wobbled) down the hall. He kneiv of recent advances in android design, but he hadn't expected to find an android -working as a tour guide. As the tour pro- gressed, he thought about all the time he had wasted at his company by personally escorting dignitaries o» a "dog and pony show." The nwre he thought about it, this was a perfect application for androids. What he didn't knOiV was that Dr. Clexus had even greater applications in mind .... Is the preceding account fictional? As of this month it is, but I believe that by the end of 1983, androids like Bothrey will be serving us in capacities similar to the one mentioned. To understand why 1 can make this prediction, we need to first understand what an android is and how it differs from its robot cousins. Next, we will explore some of the advances that are needed to make creations like Bothrey possible. Robots, the topic of last month's column, are mechanical devices that are controlled by external computers. For example, the Androbot robot, TOPO, is controlled by an external computer such as an Apple II using a language such as Logo. Androids, on the other hand, are totally self- contained. The distinction I make between robots and androids is that an android not only has a self-contained computer, but it is able to adapt its 18 COMPUTI! JuneW33 programs on the basis of information it receives from its sensors. Because this field has only re- cently crossed the boundary from fiction to reality, there is no universally accepted definition of these terms. In this column, I will use the word android to refer to a mobile, self-adapting computer system. Adaptable Androids Do commercially available androids exist today? The answer to this question is "Yes." Both the Heath HERO-1 and the Androbot B.O.B. (meaning Brains On Board) are androids by my definition. They both have sensors that convey information from the outside world and can be programmed to use this information to adapt to their environments. What kinds of things can an android do today? Since I am most familiar with B.O.B., 1 will outline its characteristics. B.O.B. is equipped with five ultrasonic sensors (of the type found on Polaroid cameras) and two infrared sensors. The ultrasonic sensors allow the android to create a map of its environment and to note the location of objects such as chairs, tables, sofas, people, walls, etc. If B.O.B. had ultrasonic sensors alone, it wouldn't be able to distinguish between people and inani- mate objects. The infrared sensors provide the extra data needed to help identify the existence and location of humans. Unfortunately, B.O.B.'s infrared sensors can also identify other warm objects such as fireplaces. While B.O.B.'s vision is quite limited at this time, one can expect androids to have more sophisticated image-processing equipment in the future. Because of the complexity of its mapping and moving tasks, B.O.B. is controlled by three 1 6-bit microprocessors. One of B.O.B.'s early tasks was to seek out humans and engage them in conver- sation, tell jokes, and follow people as they moved. The nature of B.O.B.'s tasks is deter- mined, of course, by the software it runs. The software to control an android must be quite sophisticated. Rather than programming the device to perform specific well-defined tasks, the programmer must make the android exhibit @ dilithium Press Your answer to readable computer books The Sinclair ZX81 Programming For Real AppK cations (also for the Timex/Sinclair 1 000) Handle Hurley This book will cast away any beliefs that the ZX8 1 is too small for any real programming work, tt is full of practical programs, which not only work, but are real work horses. Included is a bulk storage program, word processing, financial applica- tions, banking uses, plus educa- tional programs. Software avail- able— 1 6K ram pack necessary. Book only 1 66 p. $9.95 Book and cassette $19.95 32 BASIC Programs For The Apple® Computer Tom Rugg and Phil Feldman Chock full of programs with prac- tical applications, educational uses, games and graphics, each chapter fully documents a different program which is ready to run on your Apple computer. Software available on disk for the Apple II. Apple Dos 3.3. Book only 234 p. $19.95 Book and disk $29.95 Excuse Me, What Was That? Anton Braun Quist Included are very funny anec- dotes about things that should've worked but didn't, and things that did work but for all the wrong reasons. 160 pages $4.95 Call for the store nearest you that carries our books. dilithium Press P.O. Box E Beaverton, OR 97075 800-547-1842 Computers for Everybody — 2nd Edition Jerry Willis and Merf K. MiDer This fun to read book cov- ers all the things you should know about computers when just starting out. If you're anxious to use one, buy one, or just want to find out about them, read this book first. Includes new chapters on peripherals, telecommunica- tions and computers In education. 272 pages $7.95 Instant BASIC, 2nd AstouncSng! Edition Jerald R. Brown A valuable tool for every beginner, this second edition is full of graphics, end of chapter activ- ities, and has one of the smoothest and best- tested instructional sequences going. Says Popular Computing. " . . .a super book. It's got so much detail and depth . . . has earned itself a prime position on my bookshelf." 194 pages $12.95 TRS-80® Color Pro9.dms Tom Rugg and Phil Feldman Here are 37 fully documented programs which are all set for you to type into your TRS-80 color computer. Included are games, graphics, educational uses and practical applications. All are bug-free if entered exactly as shown. 350 pages SI 9.95 U Yes, pleue sond me ihe books 1 have indiested. I understand that I may ralurn ihetn for a tuil refund if I am not salisfrad. I enclose 9_ . plus 9 1 for shipping arid f^andling. . Tfie Sinclair ZX 81 book «9.95 _ 32 BASIC Progiams Apple book 419.95 . The Sinclair ZX 81 book _ 32 BASIC Progfsms Apple book andcassene 519.95 and disk $29.95 Cornputefs for Ewefvbody $7.95 _ Instant BASIC $1 2.95 _ Excuse Me, wtiat Was Thai? $4.35 _TRS-aO Color Programs »19.95 LJ Or call our toll free number ar^d cfiarge your order on VISA or M/C Name ^ {.- U Send me your free cetalofl— Brain Food. Adibess. city. State, Zip return to: dilithium Press, P.O. Box E , Seaverton, Ofl 97075 THE NEW ATARI 1200XL HOME COMPUTER MAKES SOPHISTICATED GRAPHICS AND SOUND SO EASY TO PROGRAM, ONLY the new ATARI 1200XL Home Computer combines cus- tom microchip technology with 64K RAM computing power to de- liver graphics and sound capabilities that are so easy to program. The ATARI 1200XL has 11 graphics modes and 5 text modes. (The Commo- dore 64 and Apple ll-e have only 2 graphics modes and 1 text mode.) Additional text and graphics modes allow users to easily program sophisticated graphics effects with relatively few commands, taking full advantage of the 256 color variations available. The sound capa- bilities of the ATARI 1200XL are also easy to program. Four distinct "voices" spanning SVi octaves are controlled by a separate microchip, leaving the principal microprocessor chips free to perform other tasks. ONLY the ATARI 1200XL offers a keyboard featuring 8 pro- grammable function keys controlling 16 functions in a 64K computer (Thats twice as many as the Commodore 64). Four new function keys enable you to lock and unlock the keyboard electronically disable the screen DMA for faster processing time, generate European lan- guage or graphics characters, turn the keyboard sound on and off or access the one-touch cursor control. The unique user-definable "help" THE NEW O A Warner Communications Company © i9S3. Atari, inc. ah rights reserved. key permits users to self-test ROM, RAM, audio-visual circuitry and keyboard functionality or call up assistance within complex programs. For even more help, Atari gives you a toll-free number to call for product and technical information (800) 538-8543; in California 1-(800) 672-1404. ONLY the ATARI 1200XL offers you a home computer com- patible with virtually all ATARI Computer peripherals and software (compatibility that other new computers like the Commodore 64 don't offer). There are over 2,000 programs and seven programming lan- guages currently available for the ATARI 1200XL New programs like AtariWritef" and languages like ATARI Microsoft BASIC, Assembler Editor, PILOT, Pascal, ATARI BASIC, Forth, and Macro Assembler offer you even greater programming challenges and flexibility ONLY Atari puts so much more in the new 1200XL Home Computer so you get so much more out of it AiARriaooxL HOME COMPUTER certain behaviors when it encounters certain situ- ations. To be truly flexible, an android siiould be able to pick and choose among several options, based on prior experience with a given situation. It it is provided with enough strategies, an android can make note of which strategies work in which situations, and dynamically adapt its programs to favor the use of these appropriate strategies. In humans we call this "learning from experience." Asimov's Three Laws If we accept that such program environments can be built, what basic behaviors should an android exhibit? In the 1940's Isaac Asimov developed the famous "Three Laws." (He wrote a guest editorial on this topic thai appeared in the November 1981 issue of COMPUTE!.) While Asimov uses the word robot to describe what I have been calling an android, these laws are useful for both types of devices: 1. A robot may not injure a human being, or, through inaction, allow a human being to come to harm. 2. A robot must obey the orders given it by human beings except where such orders would conflict with the First Law. 3. A robot must protect its own existence as long as such protection does not conflict with the First or Second Law. (from I, Rohol, 1950) How can androids be programmed to obey these laws? Keeping in mind the relatively early state of development at this time, one can still see where these laws have been incorporated into android behavior. First Law behavior can take many forms. In androids such as B.O.B., it requires that the device not run into people. When approaching a human being, B.O.B. automaticaliv stops a foot or so away and can be programmed to keep its distance from someone, even if the person is moving. The first part of the Second Law is the goal of every programmer. Who among us hasn't wished for a computer command called DWIM (Do What I Mean)? Having an android obey its user's in- structions is essential if these devices are to serve any practical purpose. As for the first part of the Third Law, androids can be provided with an ultrasonic sensor that looks down towards the floor at a 45 degree angle. Through use of this sensor, the android can avoid open elevator shafts, staircases, and other danger- ous situations that would gum up the drive mechanism. While it is easy to see how android designers can incorporate at least parts of the Three Laws into their device's behavior, there are portions of the Second and Third Law that will prove to be 22 COMPUTE! June 1983 quite challenging. These parts require that one law beobeved unless the resultant behaviorcauses it to come into conflict with an earlier law. It is interesting to note that manv of Asimov's robot stories center on conflicts arising from this hierar- chical structure of the Three Laws. For those of us working with the nonficlion aspects of these de- vices, these laws give us much to think about. Robot Personality It is quite important that a programmer choose an appropriate language when modeling robot be- havior. Fortunately, languages such as Logo and LISP provide an cxcelkMit linguistic environment for this application. These languages are extensible list-processing environments that can be used to create adaptive programs. Rather than work with an android directly, it is easier for a designer to develop android-control programs using a remotely controlled robot driven by a separate computer, in fact, much work in this field can be done with no robot at all! Powerful versions of Logo (such as those for the Apple 11 and DR Logo for the IBM PC) provide the list- processing environment as well as a "screen robot" called the turtle. Vari<.)us obstacles can be programmed to appear on the screen, and the turtle can be made to move in response to an adap- tive control program. One can monitor the robot's behavior just by watching what happens on the display. Of course, the real tun comes when a set of programmed behaviors is tried on a real robot. Some of the funniest things I have seen have come from watching an android behave "strangely." How do you respond, for example, to an android that moves partway down an otherwise emptv hallway, stops, turns to face a blank wall, and starts talking to it? Androbot founder Nolan Bushnell has suggested that robot personality is actually a collection of prtigram bugs. While androids for the consumer market are just now a reality, one might well ask how thev will be used. Fortunately, we have over 40 years of science fiction stories to help answer these ques- tions. Androids can be used for tasks as diverse as helping with the grocery shopping, "watching" the children for a few hours, greeting guests, pa- trolling the house at night - the list is endless. It is important that we all become sufficiently familiar with the capabilities and limitations of androids and robots to be able to use them effec- tively. Far from being menacing machines that deprive people of their livelihood, domestic robots and androids have the potential to enhance our lives in many ways. The extent to which they do rests largely with us, for tec will write the programs that will shape the "behavior" and "personalities" of these creations. © You need more than ABC, BPl, MAS, EEC, ESS, XYZ... Workhorse solutions for tough questions. There are lots of bookkeeping and business systems for your Commodore computen Maybe they all seem about the same. Ours Is diffierent: real business software for real computers, with capabilities you need, at a price you canafibrd. When professional computer dealers who were dtssatisified with their current accounting software were allcwed to trade it in for our System III, we were inundated. We got practically everything — BR. i. EBS. MAS — just about everyoneis. ^^ , We have general ledger; accounts - - ^"^ receivable, accounts payable, payroll, inventory,^ mail list managerrvent and much more. There are special packages for oil accounting, churcti records, encumbrance accounting, pharmacy management etc. You will like our user-defined r^rts. You decide what your Balance Sheet Pau Budget Analysis, etc., will look like. if you have purctiased a Commodore 64*, you will be pleased when you see cwr complete line of business software for the '64. This software is no rinky-dink. rip- " off software tiiat is an upgrade If frum the VIC. These are real workhorse programs ttiat use file stnjctures developed for the big bcjys. Vbu have purchased the right computer when you bought Commodore. Now do it again. Buy the right software. Buy it from the right place: your professional computer dealer. ThatS where you'll get the help you need as you start Gal! or write for the name of the dealernearestyou. Dealer Hotline: 1-800-527-4548 •Commodore 64 is a reg[stered tractemark of Commodore PO. BcK P, M^Kinney, Texas J506g ~ (214) ^42~02/S THE BEGINNER'S PAGE Richard Mansfield. Senior Editor This month we'll continue with our overview of the major categories of perso)wl computer programs. Artificial Worlds A sinnilation is a dynamic model of something, a special kind of imitation of reality. Movies imitate images and sounds, but lliey aren't really simula- tions because the events are laid out in a pre- determined sequence. No matter how many times you see Star Wars, the princess is always captured and taken to the Deathstar. If you had a Star Wars simulation, events would be unpredictable - you might be able to rescue her and even lead the Rebel Alliance to a final victory. Simulations, then, are full oi variables, events that can change. And computers are ideal tools for constructing webs of interrelated, fast-acting variables. "Spreadsheet" programs, like the popular VisiCalc financial simulator, allow you to make up lists of related items and then create interrelation- ships between the items. Tor example, you could enter all your normal expenses and link them to your income (as a percent of it). Then you could give yourself a simulated "raise" in the model by just typing over the previous income figure. All of the related items would then adjust, changing to respond to the new amount of income. It's like a spider web hit by a drop of water: some items change, some stay put. But by touching one part of the web, you can send vibrations throughout the whole structure. Like reality, a single action can cause multiple effects, and then these new changes can, in turn, cause further changes. As the price of computer memory continues to fall, we will be able to create or buy simulations of ever-increasing delicacy. When you have enough interrelated events, you've built a world. In fact, many of the popular computer "adven- ture" games (where you explore a forest, a castle, or a cave, looking for treasure) are just such world simulations. Modelling will likely be a major com- puter application in the future. A simulation of sufficient complexity would be indistinguishable from reality. Languages Languages are another major category of personal computer programs, but many people don't realize that languages are, themselves, programs. 24 COMPUn; June 1983 They're large, but they are programs. Most versions of BASIC use up about 8K (roughly 8,000 bytes) of the computer's memory. Another 8K is devoted to the "Operating System" which looks after such things as communication with peripherals like printers, video management, and so forth. You use a computer language whenever you need to communicate with a computer (this com- municating is usually called programming). Lan- guages like BASIC are programs to help you write other programs. There are dozens of languages you could try, but BASIC is by far the most popular and is available on almost every home computer. In fact, it's usually built into the computer so that when you turn it on, BASIC is waiting for your instructions. There are other languages, though, and each has its own attributes and uses. Languages do differ: some are better suited to specific tasks than others. For example, Pascal is often favored by teachers because it emphasizes certain standar- dized rules of program writing. Machine language is the fastest-running language. BASIC is probably the easiest to learn. Forth is faster than BASIC and can be the language of choice for certain game, graphics, or music programming. PILOT and l-^ogo are popular introductory languages for children, but Logo can also be a powerful too! in the hands of advanced programmers. Languages like FOR- TRAN and COBOL have been popular in the larger machines called mainframe or minicomputers. Special interests Many programmers begin to specialize after a while. You might focus on writing games or graphics programs, and find that BASIC doesn't serve your needs as well as another language would. Once you know BASIC fairly well, moving on to learn a new language is simplified. There are some underlying concepts such as loops, vari- ables, and IF/THEN structures which are common to all computer languages. After you've grasped several of these main ideas, you'll quickly pick them up when you come upon them in a new language. The Beginner's Page COMPUTE! Magazine P.O. Box 5406 Greensboro, ^€27405 © eiwasttOQ'ntm.iiic. THE PERSONAL COMPUTER YOU'LL GROW INTO, NOT OUT OF. SPECTRAVIDEO SV-318 COMPUTER COMPARISON CHART SMCIRAVIOEO &V9I4 APPLE II PLUS ATARI «» COUUOKIAEU HECU01 ftAOWSHACX Cth-OftCOMPUTEH BASE PBJCE c» »1.5«J sa99 t5»S nn t2» COMPUTINC POWER FEATURES BUILT IN ROM EXPANDABLE TO BUILT-IN EXTtHDEO MICHOSOFT- MStC BUILT IN RAM EXPANDABLE TO YES MA t4H tOK ADDITIONAL COST I6K 20K WA NO NJA leK YES IGK MR 8K 16K AOOmCNAlCOST t6K KETBDAHDfEATUfttS NUMBER OF KEYS U^A OCFihE FUNCTIONS SPCCIAL WOflD pnocEsiiwd OEhrE RATED CUtPHICS (FROM KEYBOARD) UPPERAOwEr Ca^ ICI TES VEt. YES 51 WA NO NO UPPER ONLY NO y65 YES M B NO YES YES l(] HO HO YES NONE NO NO YES GAVE/AUDIO FEATURES SEPARATE CARTmOGESLOTS ttUILT IN jOTSTICX COLORS RESOLUTKIH (PIXELS SPRlTtS SOUND CHAHNtlS OCTAVES PEfl CHANNEL ADSR FNVeiOP^ T6S YES t6 3 YES NO MO lb 2WT160 WA 4 NO TES NO NO NO NO 16 s 3 9 YES HO NO 4 !»r IH NTA YES ftO HO 10 NO PERlPMliUL SPECIFICATIONS CASSETTE AUDIO K) BUILT IN MIC i^$K onrve CAPACITY ILO* CftOf ?LB 2 CHANNEL YES YES YES 1 CHANNEL WO NO lOK HO 2 CHANNEL YES NO KM, HO 1 CHANNEL NO NO NO 1 CHANNEL »Q NO NJA 1 CHANNEi NO NO I/UK NO CPtti' cOMPATiSJirTV ( 80 cDiumn prDgrwm) CPrti- 32 CPM- 30 YES YES HO — HO NO IW NO — MO NO NO NO NO ' 16K ujc «Min^»« plus i&J^ ^itgfi-:. ^so(^^ FOR UNDE "* Apc* It car kchjI nOfvl « or 80 raliimn CP/U Mtcrosotl n i reiji^terrd Uadtmjrt oJ MreE4Ki:qris40aAimnCP/U ^PlMisi^rulcrnark 01 [>(jibf Res<tn. Inc RS300 ^«^rTRRWZ7£Z7 SV 318 PERSONAL COMPUTER SPEC I RA VIOCO. INC . 3'? W 3?>h SI . N V . N V I0018 SodtY. mony persona/ computers will become fomorrow's iunk in me attic. Tt^e SV-3IB is one tt)at will not. Because as you get better. It geti better. It does so because oUts capability one* expar^dability—bott) tar beyor\d tt}ose of any other oltordoble compaler. CA PASIilTY. Ttw SV-3)S iin 'I just more capable. It's nnuctr more capable. No olt\er computer at everj tv/lce fhe price combines all these extraordinary features: 32K ROM expandable to 96K: 32K RAM expandable to I44K: Extended Microsoft Basic (the industry standard): even Standard CP/M BOcoiumn capability so you con Invnediafely utilize over ;o,000 existing soflwore programs. The SI/-3I8 also has a unique built-in joyslicld cursor control— an immeasurably useful leoture when it conrtes fa playing your tavorite video gome- CXPANDASIUTY. As you become more and more sKiiilul with computers. yoWii love how the $V'3I8 "stretches" to meel your demands (arjd acluaily leads you In foscinaling, new directions), for one thing, oil eleven of our important peripherois are ovaiiabie immediately. With most other models, you hove fo wail months. For another, the SV-SIS is beautifully designed to interface with new options as they become available. AFfORDABtLiTY. The SV-3IB Is not only eminently ottord- able, it's the first true bargain at the computer age! Besides home t^dgefing. business applications, word processir^g, programming and seltieoching. the SV-318 is the best entertolnmeni value in town. A/or only con you use it with your TV fo play hundreds of different video games, you can also use your SV-3ia with a TV as a drawing tablet or music synthesizer. In play, as in work, the SV-31S will continually expand to meet your potential. Whether you're just welting your toes in computers, or iulty asoil on the waters, the SV-3i8 is a cornpufer' that will serve you lor many, many years. You see, we believe that even in the computer age, you don't become an object of real value unless you're around for a while. Questions Beginners AsIc Tom R. Halfhill, Features Editor Are you thinking about buying a computer for the first time, but don't kiiowniiything about computers? Or maybe you just purchased a computer and are still a bit baffled. Each month in this column, COMPUTE! ivil! tackle some questions that we are asked by beginners. QWhen the new Atari 1200XL computer was announced a few months ago. Atari said it would be "software compatible" with the older Atari 400 and 800 models. Doesn't this mean that software which worked on the 400/800 should also work on the 1200XL? Then why won't certain cartridges for the 400/800 fit into the 1200XL's cartridge slot? A To be fair, this isn't Atari's fault. But before we get to the cartridge question, let's define exactly what is meant by "software compatible," since this question is coming up frequently, too. And this definition applies to all computers, not just Ataris. Atari 400/800 software is upward compatible with the new 1200XL. This means that programs written properly for the 400/800 also will run on the 1200XL- although the reverse is not neces- sarily true. If a program is specifically written to take advantage of the 1200XL's special features {such as the HELP or special function keys, or the 64K of memor)'), it probably won't work on the 400/800 unless adjustments are made. But note that we said "properly written" software. Some programmers take shortcuts which can cause compatibility problems. Usually these shortcuts involve what are known as "illegal calls" to the computer's operating system. The operating system is a built-in program in all com- puters which does routine "housekeeping" tasks necessary to a computer's operation. Machine language programmers sometimes "call" routines built into the operating system to save themselves the trouble of writing similar routines. This is perfectly okay, except that these calls must adhere to certain rules to insure that the program will work on all future versions of the operating system. Atari's operating system manuals state that if these rules are obeyed, future compatibility is assured. 26 COMPUnS June 1983 That's why some machine language programs won't run on all versions of Ataris - the pro- grammer took an unauthorized shortcut. Several popular commercial games were affected in this way when Atari revised the 400/800 operating system about a year ago. Late-model 400/800s have a "Revision B" operating system which fixes a few bugs in the old one. The changes were subtle, but some programs which depended on the old operating system were rendered unworkable. The 1200XL has a somewhat different oper- ating system than the 400/800. Among other things, it includes the 1200XL's built-in diagnos- tics. Machine language programs for the 400/800 which call the operating system properly should have no trouble running on the new computer. Now, as for the cartridges: it's true that some Atari 400/800 cartridges made by independent software companies will not fit the 1200XL's slot. However, all cartridges made by Atari do fit. The slots are identical, except that the 1200XL has less room around the opening (the 1200XL's slot is external, while the 400/800 slot is beneath the front hatch). Some independent software com- panies made their cartridges oversized, which is why they won't fit a new slot. Probably these companies will issue new versions to fit the 1200XL. If you recently bought an oversized cartridge for a 1200XL, you may be able to exchange it. If you can't, the only solution is to take apart the cartridge. The "cartridge" is really just a protective plastic housing around a small circuit board. One screw or some glue usually holds it together. When the housing is removed, the board can be plugged into the slot. But do this only as a last resort, because it involves two dangers: (1) Exposed circuit boards are deli- cate and easily damaged by mishandUng, and (2) if you accidentally manage to plug in the board upside-down, the board can be ruined. If you take apart a cartridge, we recommend clearly marking which side goes up (or forward in a 400/ 800), and fashioning some sort of protective cover out of cardboard or a flexible plastic cassette tape box. ^\ I heard that Commodore recently intro- \X duced a new model computer called the "VIC-21," and that it is already being sold in If You tjked Donkey Kong, VbulfLove' 19. MPMAN. THECOMPUTER ACTION GAME, \ . If you liked jumping over barrels arrd climbing ' ladders to save damsels in distress^you'tllove the blazing excitement of JUMPMAN. Your incredible speed and jet boosters let you leap from girder to VinilSiWsfSK^ MKnBi3iimnSMmutilsKmuW»lkKl¥ilMliR bombs plwhted in Jupiter Headquarters. But it's not easyjmd there are thirty levels of difficulty. You'll ham to dodge missiles, killer robots, flying saucer^crumbling girders and vanishing escape Routes. In the heat of battle, JUMPMAN must keep a cool head. .-hsa-ssfi i The Award-Winning Computer Qames .■Epyx,W43 Kiel Court, Sunnyvale, California 94086 ■ .KEY KONG l» Designed by Randy Glover INlntgndJol America, tnc. some cities. What is the VIC-21? Why didn't we read about it ahead of time? A Not to worry, we didn't let you down. There is really no such thing as a VIC-21 - even though a store in Boston started selling them a few months ago. Confused? So were a lot of Bostonians. What happened is that a store began advertising a sale on the "VIC-21," which was really just an ordinary VJC-20 with a 16K memory expansion cartridge included. The package sold for about $200. As a promotion, the store pasted stickers on the boxes which said "VIC-2r' - apparently derived from the sum of 16K plus the VIC's built-in 5K of mem- ory. When people started calling competing stores and Commodore about the "new computer," Commodore immediately disavowed any connec- tion with the promotion. Although it has been hinted that someday Commodore may upgrade the standard VIC, possibly with 16K, no such plans have been announced. ^ COMPUTER /BASF CASSETTES/ -DPS )THE WORLD'S FINEST Data media for all microcomputers • Used nationwide by software manufacturers, tiobljyisis, sctiools and businesses > Premium 5-screw stiell witli leader fits at! standard recorders CASSETTE STORAGE CAOOY KE*' TTUCTOn FEED aE-afTWJkMK CUSTTTC LABELS ORGANIZE YOUR TAPES! < $2»S EACH GET ONE CADDV FREE! Buy 2 aoi. Cassettes & One CaddY. Get One Caddy FREE! tji mil KPifcrs Aucu^i I J udi • SATISFACTION GUARANTEED OR YOUR MONEY BACK • FOR IMMEDIATE SHIPMENT USE YOUR VISA OR MASTERCARD OnOER NOW . CALL 213/710-1430 ..ORDER FORM-. ...___.. MML TO: VORK 10~Computef more m* llUtfJi IDOICM ffflM. 24573 (dtttiO^e Sr . #CM. CjOOflJ Park. CA 91307 o« n '" .: '3» c-ia n «oo ; J '♦■" SD4d stpanltti. ShipnlBiiti »re fry U.F S. uaIhi Pwcffl P«l cao n lOM :;'■«> reque»i«d Soiei. ciddtci. ma blini labaii jre um oi H>rfs« [J iM r. s^i y^ Michael Riley hsscJeve\op<'d ^ /- an e:*ceUent, professional data "^ ' base prograrn that contains many \ / features - too many +o cover in a \ ( shori rQ\j\e^. Suffice itiosay that \ I yo^ ^^^ spend much more for a high / \ quality data base, buf Ws doubtful / \^ sjou wiU find the f lex^bUity of J an application program suchias FLEX- FILE. r^^ For Cb^. PET, CBNrt V\C.\Ni-fri32K RA^A.Oual, single or two single drives. . \ *H0, If you want FLEXFILE ^ flex^bilrtv ca\\ 215-822.-7729. Dealer^ call 215-822-3171 PET/CBM/COMMODORE 64 RpeEClip Professional Word Processor at a Breakthrough Price PapeiClip™ performs all the advanced features found in Word Processors costing much more. . . 1) Full screen editing. 2) Copy/Transfer sentences and paragraphs. 3) Insert/ Delete sentences and paragraphs. 4) Headers/Footers/Automatic page numbering. 5) Justification/Centering. 6) User defineable keyphrases. 7) Supports both cassette and disk. 8) Variable data - Form letters. 9) Horizontal scrolling up to 126 characters. 10) Insert/transfer/erase Also available for Commodore 64 Requires Basic 4.0. 32K memory. ,00 U.S. Call or write for the store nearest you. BATTERIES inCLUDED 71 McCau I Street Toronto. Ontario Canada M5T 2X1 (416)596-1405 columns of numbers. 1 1) Add/subtract columns of numbers. 12) Supports most dot matrix and letter quality printers. In fact, a printer set-up routine is supplied to take the best advantage of the printer at hand. 13) French and Math technical character sets available. TWILIGHT OF THE COMPUTER HACKER Fred D'lgnazio, author of the popular COMPUTE! column, "The World Inside The Computer," begins a second column this month called "On The Road." He will travel around the country visiting user groups, workshops, seminars, conventions, or anywhere else computers are having an unpact on everyday life. This month I begin a new column. My assignment; To go on the road, living the life of a carefree wanderer; to seek out computers and people; to write about the good things or the bad things - whatever I find. The Twilight Of The Hacker My first journeys as a gypsy computer reporter were brief and confined to my home city of Roanoke. The first place I visited was the monthly meet- ing of the Roanoke Area Computer Enthusiasts (RACE), The meeting w^as held on a weekday evening in the Roanoke Valley Science Museum. I went to the meeting with great enthusiasm be- cause several members planned to demonstrate a full-blown VIC-20 system (it occupied almost half the table). I especially wanted to see the demon- stration because I will soon be writing a "kids and computers" column on the VIC-20 (and Commo- dore 64) in the new COMPUTEI's Gazette for Commodore magazine. The VIC-20 demonstration went fine. And we were also treated to a detailed description of IvACE's current project - a homebrew computer modem. But what really impressed me was the club itself and the people who formed it. The club was small, old, almost exclusively male, and made up of computer hackers, people who enjoy rolling up their sleeves and diving into the bits, bytes, chips, and circuit boards that make up the average computer. 30 COMPKTl! June 1983 The evening was solid technically, and the people were all very nice, but I left the meeting feeling a little drained and lethargic. The club members called themselves "enthusiasts," but where was their enthusiasm? Computer "hackers" were the pioneers of microcomputing. They were the enthusiasts - the zealots, even - who got this industry started, in the 1960s and the 1970s. Now we're in the mid- 1980s, and what has happened to the hackers? They're the computer elders who are being shoved aside by a stampeding horde of new personal computer users who seem to share none of their characteristics. Enter The Computer Humanists What are these new personal computer users like? To find out, I went to two recent events - the Computer Faire the following Saturday and Sun- day at the science museum; and the "Computers in the Schools" conference at Hollins College, just outside Roanoke. The best way to describe the new personal computer users is to say that they are the kind of crowd you'd find at a Roanoke bowling alley on a Friday night - only more diverse. There are a lot of them. And they are young, old, and in between. There are lots of women and lots of kids. The new personal computer users talk funny, almost like regular people. You don't hear a lot about bits and bytes. Instead, you hear about computer model numbers. And computer com- ponents. And computer software. Most of the discussion centers on who has what piece of new software for which machine, and how it's the "neatest thing you've ever seen." Another thing that distinguishes this new group from the old-line hackers is their energy. Everyone is so excited. Parents are excited about bringing all the new educational programs into their homes. Kids are excited about the games. The Home Accountant. m The #1 best-seller. Any home finance package will balance your checkbook. But to become ttie #1 best-seller you've sot to be something special. The Home Accountant" is. It's the only one that prints a net worth statement and a personal finance statement. So you know exactly where you stand financially every day of the year. It will even print your checks, automatically. Not oniy thatjhe Home Accounta nt™ lets you label every transaction. Just imagine sitting down to do your taxes and having every penny you've spent and earned neatly listed by category —and available at the touch of a button. It's an incredible time-saver. You can also create bar, line and trend analysis graphs for every category- in color. It's great for realistic budgeting. Sound amazing? Wait, there's more. Let's say you write a check to pay your Visa.The Home Accountant" automatically debits your checking account and credits your Visa account. And it does this with every one of the two hundred'* budget categories: credit cards, checking accounts, money markets, cash, rent checks, insurance payments— you customize your own financial package. Check out The Home Accountant" soon. You'll find it does a lot more than simply manage your money. It manages your money simply. *The Home Accountant™ is available for the Apple II/IBM Personal Computer/Atari 400/ 800 Computers/Osborne/TRS 80 Model III/ Commodore VIC 64.The actual budget capacities will vary with each computer. Continental Software A Division of Arrays, Inc. m It sells the most, because it does the most! Continental Software Co.,1 1223 South Hindry Avenue, Los Angeles, California 90045 Telephone (21 3) 41 7-3003 • (213)417-8031 YQirVEGOT FROM Nowmnfl END OF THIS PAGE 10 BECOME GDI See all those glittering diamonds? Grab 'em. You need 1,000 diamonds fast. 'lo score, you have to buiTow deep. Deep into tlie aivems. You craftily cop a dozen jewels. Then, jump to tlie ledge below. Then down to ancjtlier. And another Hut, STOP! 'Iliere's noUiing but an abyss below. Notliing for you Uiere except a bad fall— and even worse, delay! No, don't go tliere. You've already stripped that vein of diamonds. Go where no one has ever daixid venture before. Follow the cavems Deeper and deeper, Down the ladders. Over to tlie right — more jewels ... and CURSiiS!... you've fallen, And you're losing time. Grab those diamonds. Ah ha! You've reached 1(X)0! Ilie Mame Spirit has been set free. Now you must capture it. flashlight. 'Die Flame Spirit is very near. A flicker Out of fjie comer of your eye. Shine tliat light! There it is. Now, kneel E before the Spirit and grab it. Gotcha! Run! Run to the 'lemple. Watch out! Behind you! A vampire bat trying to steal the Flame Spirit. Climb down, below the ledge. Another bat! Down, 'lo tJie very bottom of the mountain. To the pit. And the darkness. Lit only by the shimmer of diamonds. Suddenly thens's a rush of inovement. . . a giant spider— after you- Quick— down another ladder Listen! Ghostly music floating thn)uj^i the black tunnels, 'lliat means tlie Flame Spirit is hiding nearby lire music grows louder as you draw closer Now softer (cjuick, go back the other way). Louder again. Shine your Run. Jump. Up to the ledge. Hurry! Jump again! Aamrgggghlihh! You're aiught. Woven in a tangled web. Hurry, break Irwse before he returns and ycxi're devoured. Ah! You've freed yourself. You've lost lime, but you've gained character Now, on to tlie Temple. But beware of tlie guandian flames— one false move and youll end up charred . . .and out of the game! Get to tlie Temple Portal, tlie Spirit in your grasp. Shine your light on tlie giant guardian skull. You kneel. (Not out of nespect, but out of need— for without kneeling, entering the lemple is forbidden.) l1ie entrance yawns open. And you leap in. There, enshrined deep within the sacred Temple, emblazoned witli gold, is tlie sovereign crown. You must get tliat crown. Witiiout it, you cannot become Mountain King. Willi it, you'll rule. But now comes the tough part. Can you make the treacherous climb back to the surface? Can you avoid tlie relentless bats and spreading cave fires on the way? Can you even find the way? Get Mountain Kin g.'" Plug it into your home computer. It will ])lunge you into tlie depths, and lift you to Uie heigliLs. ANOTHER GAME TO DIG INTO. It's Boulders tind Bombs .'" One to four can play And witli 99 levels of terrific tunneling adventure, it's every bit as involving as Mountain Kin g. Your challenge is to tunnel to safety beneath liie surface of an unknown planet as hostile, alien vultures seek to turn yxni into a buried fossil, entombed in an alien life form. While day turns to niglit above giX)Uiid, you use your tmsty n)to- augcr to claw a patli to safety beiowgnjund — tlin:)ugh tons of eartli, boulders, and Oie ever-spreading green cave fijngus. ROM Cartridges for: Atari®400/800™' ( Mountain Kin g available soon for Commodore 64'" and VIC-20'") I 1983 CBS Inc. -MQUNIAINKING-isatradaiwk Ql Kay EnEerphses Cd- 'Alan' is a t3d£mar1( of llvi. hi. 'ConnolofE M' and 'VIC-2fl* 3Pi trxlernailfi cf Cwrtmaiofe Bt^iness Uadines. Ira:. Fortunately, you can unearth time bombs along the way to blast away the hazaids the vultures toss at you. But the crawling fungus spreads as time runs out. Now that you know the names of these challenging new games, and you know what it's like to play them, there's one other tiling you should know : They're from CBS Software. And even though tiiat name says a lot about quality entertainment, we haven't mentioned it until now. NEW! MOUNTAIN KING Because at CBS Software, we believe our computer pnagrams should speak for themselves. NEW! BOULDERS AND BOMBS Soitwaie BOULDERS and BOMBS oftwaie CBS Software. You knowwhat you're gifting. Teachers are excited about the ways they can use the computers in their classrooms. I sensed some fear and anxiety in this group, too - a certain ten- tativeness about really moving into this strange new world. But mostly I sensed excitement a lot of it. And the questions. Here is where the com- puter hackers and humanists diverged com- pletely. The hackers asked how soldering on cer- tain boards is done and about which section of memory is switch selectable. The humanists asked how computers for very young kids would alter the way kids develop their fine motor skills and the way that they get along with other people. For example, I conducted a workshop at Hol- lins College on "Computer Literature." During the workshop a man raised his hand and said, "I am an artist and a teacher. I teach elementary school children how to paint and draw. If httle children learn to paint beautiful pictures on a com- puter just by pressing a couple of buttons, how will they ever learn to draw on paper?" How do you answer a question like that? I didn't try, but other people in my workshop did. One woman, an elementary school teacher, said, "Who cares if they draw on paper? In the future, no one will be using paper. They will be using TV screens for everything. They are the new medium for creative expression, not paper. Kids have to learn how to do this to be prepared." Another teacher disagreed. "If kids only learn how to push buttons," she said, "they'll never develop their bodies. Their gross and fine motor skills will never be developed. These skills are crucial to a child's becoming an adult." Another teacher added, "And what about the pleasure children have using art materials? Children who only work with TV screens and plastic buttons will never know the joy of using gooey fingerpaints, and clay, and paste, and making cutouts out of construction paper. It doesn't sound modern to me, it sounds de- prived." Jiminy Cricket The Computer During the workshop, 1 told the teachers about my concept of the "Computer Friend." I said that I thought all personal computers would one day assume human-like qualities and become intimate friends of their human masters. One teacher applauded this prospect. "This will be a boon for human relations," she said. "It will let everyone, especially family members and young people, work out their feelings first with their computer. If something is troubling them, they don't have to keep it bottled up inside them. They can tell their computer friend. Then, after the matter is aired, they understand it more clearly, and they feel better about it and can ap- 34 COMPUffi! Jyne1983 proach members of their families and other human beings. A lot of situations are like powder kegs, ready to go off. Maybe the computer friend will help defuse them." This point of view was echoed by another member of the workshop, who said she thought the computer friend might be like Pinocchio's friend Jiminy Cricket. The friend could be a per- son's conscience. The friend would hear a person's deepest secrets, his darkest and most whimsical fantasies and wishes. At this point, two teenage girls raised their hands. "All this sounds dangerous to me," one of the girls said. "If computers are so friendly, they might lure people away from interacHng with each other." "She's right," said the other girl. "How can a human being be as pafient as a computer friend? How can a person give another person their undi- vided attention the way a computer friend can?" "And what about babies and toddlers?" added a woman teacher. "They may learn early in their lives to relate to a computer friend. But the friend may become a substitute for other people. This could stunt a child's ability to get along with people around her. Her eariiesl model for socialization wouldn't be a person, it would be a computer." Computer Intimacy Vs. Computer Literacy In one of our workshop discussions, I questioned the big focus on computer literacy. I said that com- puter literacy was fine now while we were still in an age of transition from a non-computerized society to a completely computerized society. In the future, however, when people have fully ac- cepted computers and when computer technology has matured, we will move beyond computer literacy into computer intimacy. I compared my audience to computer hackers, and said that it was obvious that the change from literacy to inrimacy was already occurring. People were worrying less how computers worked and more how to "drive" computers the way they might drive an automobile. Also, they were show- ing concern about the impact of such a powerful technology on their lives, their students' lives, and the lives of their children. 1 likened intro- ducing a computer into people's lives to sitting behind the wheel of a powerful race car. The car can take you places at breathtaking speeds, but, if mishandled, it can maim and ruin. Computers are not a technology of the body but a technology of the mind. As carriers, amplifiers, and multipliers of symbols, concepts, and ideas, they are far more powerful than auto- mobiles. Whether they cause us to benefit or suffer depends on how we use them. @ No one, not even the author, has ever achieved the last Gridrunner. it is an extremely fast- paced arcade- quality game designed to test your coolness under fire and challenge your reflexes. As the pilot of the Gridrunner, a combat ship, you must annihilate the various enemies traveling along the "Grid." High scores are possible only through the mastery of the patterns of the X/Y Zappers and the Gridsearch Droids which, when destroyed, mutate into potentially lethal Pods. Gridrunner has 32 levels of diffi- culty (20 levels in the VIC 20 ver- sion). To this date, the 13th level has been the highest achieved. Gridrunner is available for VIC 20, Commodore 64 and Atari 400/800. Can you beat Gridrunner? See your local computer or games dealer and find out. Human Engineered Software 71 Park Lane Brisbane, CA 94005 a division of USI HOW TO BUY THE RIGHT PRINTER Charles Brannon, Program Editor You discover bugs (errors) in your 50-line BASIC program. If you could only see more than 20 lines at a time! You use your computer to keep track of your record collection, but realize that the valuable information on your TV screen is transient -erased when you "Press RETURN to Continue." You subscribe to a telecommunications network and despair when your hard-earned 300-baud text scrolls off the screen into oblivion. You may feel that you need a permanent record of your text, want to write (word process), or hang your artistic efforts on the wall. Even though prices are falling, a printer is an investment. Your printer could cost more than your computer. After you've realized you need a printer, you need to decide how much printer power you require. Applications First you should identify your application. Do you need only paper listings of your programs? Simple "printouts" from your home financial program? Will you want to use your computer for word processing? Do you need to print on plain paper, on special forms, or to produce extra-wide accounting reports? Consider also the fact that as you expand your computer system, your needs could change. Does a certain printer have enough features to be satisfactory in the long run? Re- member that most printers cannot be expanded as easily as computers can. Printing Techniques Printer manufacturers have come up with many ways to solve the problem of getting words onto paper. The most obvious method is similar to the way that typewriters print. A formed character "stamp," usually made of metal, is struck against a ribbon that leaves an impression on paper. On a typewriter, a series of levers controls which char- acter hits the paper. IBM invented the "type ball," a hemisphere containing all the characters in vari- ous rows. To print a letter, the ball turns and tilts to select the right letter, then the whole ball strikes the ribbon. 36 COWPUrei June 1983 It is not easy to interface a computer with a typewriter. First, typewriters are not built to tol- erate continuous operation. Second, some of the interfaces are cumber- some and expensive, usually a series of solenoids that push the levers around, or a keyboard overlay with a separate sole- noid for each key to mimic a human typist. The third problem is speed; you still can't drive the typewriter faster than about ten characters a second. The old-fashioned typewriter layout is prone to jamming; the type ball is too slow. Printer technology diverged to solve the problem. Dot- matrix printing was developed as an appropriately digital way of producing text. The daist/ wheel was developed as a high-speed, reliable way of printing formed characters. .-.:.;;i- .-. .^^■tffe "rrr^T^iTTTT". ^ S[P ^ \ ^. ^^ — il K*^-^-»* iD^^r.— /Sm p K?^^>j ^K^ ^M il ^ ■P!^'\ :i '/y * 3 Jl Hi Close-up of an IBM Selectric ball. Some electrotjic type- wriiers. can also fund km as computer printers iviih the proper interface. So7m' letter-quality printers are called "daisy wheel" printers because they use a print head shaped like a daisy u'ith letters on the ends of the petals. A The Interbus Series. Three interfaces for the VIC 20 and Commodore 64: one for IEEE 488, one for RS 232 and one for Parallel. The VIE and CIE are IEEE 488 interfaces for the VIC 20. When plumed into the expansion port, the cartridge is "transparent," that is, the user can still attach other peripherals without any interference. Devices such as 4040, 8050, 2031, 2032, 4022 and 8023 can be controlled. The IEEE software can be called by using the 'SYS' command, even in the middle of a BASIC program. The V232 and C232 are serial interface cartridges which allow connection of various input/output devices such as printers, modems, plotters, etc. to VIC 20 or Commodore 64 computers. Features include: positive and negative voltage swings to meet full ElA standards, strajK and jumpers to eillow reconfiguration to meet pinouts for any RS232 device, and software selectable reconfigura- tion such as baud rate, parity, and duplex mode. The VPl and CPI are parallel interfaces for the VIC 20 and Commodore 64. These interfaces provide direct BASIC use of the parallel printer bus and give "invisible" access to the bus. The VPl can be used only on the VIC 20 and uses the expansion port. The CPI will work with both the VIC 20 and Commodore 64 and does not use the expansion port. The CPI also has switches for set- ting insertion or deletion of line feed, conversion of Commodore ASCII into standard ASCII or visa versa, addresses printer lo device 4, 5, 6 or 7, and allows normally unprintable Commodore characters to be printed in a recognizable form. B Expandoport Series. Expandoport 3 and Expandoport 6 are three- and six-slot expansion boards for the VIC 20. Each slot on the Expandoport 6 has a switch for controlling power to that con- nector. The switch allows the use of cartridges which respond to the same memory space. The Expandoport 6 also has a fuse and reset switch. The fuse prevents excessive current drain from the VIC 20 and protects it from 'shorts'. The reset switch allows the user to 'Restart' the VIC 20 without turning power off. This feature allows RAM, which is located in the ROM expansion area, to be protected during 'Restart'. Expandoport 4 is a four port expansion board for the Commodore 64. It has the same features as the Expandoport 6 and even allows for tlie use of varying width cartridges. C Terminal Pak Series. The VTE 40 Terminal Emulator (VTE 40) is a hardware and software package which converts the VIC 20 into a 40-column communications terminal. TTie VTE 40 cartridge is complete. Various set-up parameters such as baud rate, f)arity, duplex, and bits per character can be selected through a 'menu' format, VTE 40 features are: 40 x 25 text display, user definable communication specs, smooth or normal scroll, print infor- mation to printer or disk, generation of control codes, selective omission of data, continuous status line. The CTE/VTE Terminal Emulator (CTE/VTE) is a software program which converts the VIC 20 or Commodore 64 into a ter- minal. The user can 'software select' the baud rate compatible with the modem used. Full upper and lower case characters are supported D Audio Link. An audio cassette adapter interface for the VIC 20. Features include: use of regular cassette recorders, conver- sion of VIC 20 digital data to audio and visa versa, normal and inverted cessette signal, remote on/off control and control of external devices. A Interbus Series. B Expandoport Series. C Terminal Pak Series. D Audio Link. Call toll free for nearest dealer l-SOO-527-5285 Lifetime warranty available upon return of Product warranty card E VRAM. These memory expansion modules are designed to provide additional user programming space for the VIC 20 system. VRAM plugs into the memory expansion port and requires no additional power or modification to the VIC 20 system. The units are packaged as 3K, 8K, 16K and 24K modules, Strapping is provided for mapping 8K blocks of memory into the various available memory blocks. VIC 2il™ and Conraodore M™. CBM"™ and PET™ are rci^ercd IrademariB ol Cbmnujdore Business .Machines. Ejlpandoport, Audio Link. Ijilertius, Tfrminal Pak. VRAM and Monilar-link are coiiywrited by Mkro Systems Devdopment, Inc MICRO SYSTEMS □EVELOPMEIMT, IIMC. nice SHADY TRAIL • SUfTE 1D4 • DALLAS, TEXAS T^SHS Some Iclter-qiwlilif printers ii^e a "ihiuiblc." a vnrialioii of the daisy wliccl. Dot Matrix Take a look at the characters your computer dis- plays on your TV screen. Each one is made of tiny dots, usually within an 8 x 8 box. Figure 1 shows a typical dot matrix representation of the letter "A". The dots are formed by a sweeping electron beam in your TV tube. Dot-matrix printers also use a series of dots to form characters. The heart of a dot-matrix printer is the print head. Imagine it as a series of vertically stacked pins (see Figure 2). Eacli pin can be "fired" inde- pendently. To print a hne of text, the print head sweeps across the paper. Characters are not formed "all at once," but one vertical line at a time. There are several ways to print on the paper. Impact printers strike the pins against a ribbon to leave an impression on paper. Thermal printers use a column of tiny "spark plugs" to electrically vaporize (burn off) a special aluminum coating on thermal paper so that a black surface under the aluminum will show through. !iil<-jet printers spray ink through tiny holes. Each dot-matrix method has its ad- vantages and disad- vantages. Thermal printing is much quieter (and cheaper) than impact printing. Some thermal printers i^ are virtually silent. 'a print head from a dot-umtrix ^"'^-i^'t prm'ters are printer. The ends of the tiny even quieter, but loires which form the characters their price places are barely xusible at the front- them outside the center of the print-head. home computer 38 COMPUTE! June 1933 market for now. hnpact printers, despite their sound and higher price, do not require special thermal paper. Another disadvantage of thermal paper is that it does not age well. It oxidizes over time and darkens appreciably. Friction Vs. Tractor Also borrowed from typewriter technology, a platen is found in most friction-feed printers. The pressure of the rotating cylinder feeds single-sheet or roll paper. Unfortunately, friction-fed paper is subject to slippage and skewing. After ten forms, your printer may no longer be lined up with the paper. Skewing varies; some printers have excel- lent friction feed. However, the reliability of a tractor feed mechanism is generally superior for processing multiple forms. The "teeth" of a tractor feed mechanism fit into small holes on each side of the paper and pull it through the printer. Tractor feed is more expensive and requires continuous special pinfeed paper. However, the strips of holes can be detached and the paper separated into 8'/2"x 11" sheets. 1 f i II I ,,_-_„, A tractor-feed printer ivifh iSfi toothed Tc/ict'/s autl jk-rfonitcd paper. (The ri^ht-hand tractor /s unhitched.) Print Quality Obviously, formed character printers (daisy wheels) produce the best-looking text, indistin- guishable from a tvpewriter. This is important for business, where the "computery" style of dot-matrix is often unacceptable for letters. Some dot matrix printers, however, have exceedingly fine print quality. This is called correspondence quality, and can approach a typewriter's quality. Correspondence quality printers space the dots closer together. A 5 x 7 character matrix is standard on average dot-matrix printers, but cor- respondence quality printers use 9 x 9, 9 x 14 (or 9 X n, where n can vary), or even higher densities. Related to dot density are lowercase descen- ders, the "tails" on the letters g, j, p, q, and y, A 5x7 matrix is not really adequate for good de- scenders, which should extend at least two dots below normal letters. See Figure 3 for an example. flfl flfcade fidveflture iJ^Bfei, ♦r/^' A A.E.'s, produced by an industrial giant to control pollution on Earth have slipped quality control. They attack relentlessly in waves from the sky Your mission: to drive them farther and farther into space. With each successful defense, you are transported to another, then another more distant 3-D environment. With these progressively difficult scenes, A.E. delivers the ultimate challenge. Never has a computer game required such precision, such timing. You'll be hooked from the very start. A.E. (it means sting ray in Japanese) provides such enduhng satisfaction on every level that it will become your persona! standard of excellence in computer gaming. Now available for Apple II, II+, lie and Atari 400/800t 'Appte and Alan ara reglsl^ed Irademaiks of Appte Compuief. Inc.. and Atari, Inc. respectively. ^BrrjderbundSoftujare Broderbund Software, inc. 1938 Fourth Street San Rafael, CA 94901 (415)456-6424 Descenders can make text easier to read, and if you do a lot of proofreading or copy-editing, this can make a difference. Character Sets Every printer has a slightly different typeface, or character set. The character set is the various pat- terns that the print head uses to form a character. Some printers use a simplified character set for high-speed draft printing. The patterns are less dense. However, that same printer might also offer high-quality dot-matrix printing, but at a lower spteed. A printer should have upper- and lowercase, and all the normal symbols found on your keyboard. Some printers have special line- drawing graphics characters or foreign language symbols. Compare sample printouts from several printers wheri making your choice. Variations Dot matrix printers can also perform special tricks with the characters. They can elongate (print twice as wide) and condense (twice as small). Some printers can automatically underline text, others have horizontal or vertical tabs, or can double- strike or print in boldface. Printers can also vary the height of a printed line. Most printers are able to form feed (automatically advance to the top of the next page). This is done by sending a special message from your computer to the printer. Grapliics In addition to printing predetermined patterns (ordinary numbers, letters, etc.), some printers also let you control the print head directly to create your own custom graphics. You can create special symbols. And you can "dump" (copy) graphics from your computer, if it has a high-resolution screen. High-resolution is measured in dots-per- inch or dots-per-Une. You may not need more resolution than your computer has. If your com- puter can display 320 dots per line, you won't necessarily need a printer's capability to print 960 dots per line. One caveat of high resolution is speed; the more tiny dots you have to control, the more data needs to be sent. You may require a special machine language routine to effectively use dot graphics, so check what's available before buying. Printer Software Look over the available software which is com- patible with the printer you're considering pur- chasing. If your favorite word processor doesn't support the "FastPrint 110," you may not be able to use some of its features. However, some word processors let you embed special characters in your text to control any printer. Speed Generally, dot-matrix printers are fast 60 to 80 characters per second (CPS). Letter quality printers (daisywheels) run from 25 to 50 CPS. Some low cost daisywheels print at around 10-14 characters per second, so consider your patience threshold before you buy. Several tricks are used to increase throughput. Time normally wasted during the car- riage return, when the print head has to travel from the end of a line back to the beginning for the next line, can be used by printing backwards on the return. This is bidirectional printing, and can speed up overall output significantly. Another trick used in conjunction with bidirectional printing is logic-seeking. A logic- seeking printer attempts to print the shortest line. If necessary, the print head may return at high speed to print a short line. Some printers, espe- cially daisy wheels, also boast space skipping. This is most useful when the printer fills in blanks on a pre-printed form. Instead of advancing at a uniform rate, the printer counts all spaces re- ceived, and then quickly jumps directly to the next non-space printing location. Random Access Printer To free up the computer while the printer is zip- ping away, some printers contain an internal buf- fer. A buffer is just RAM memory, like your com- puter's RAM, but is inside the printer. The buffer accepts characters from your computer as fast as the computer can send them. It then feeds the characters to the printer at a more leisurely pace. If the buffer is large enough, your computer will be available almost instantly for other non-printer Figure 1: Dot Matrix Figure 2: Print Head Figure 3: Descenders • ••• ••: 5x7 "y" 9x9 "y" 40 COMPUIB June 1983 For Heroes Only! Blade of Blackpoole step back in time and join the searcti for the magical sword of Myraglym. Travel cautiously on your journey for yotJ will encounter dangerous serpents, spine-ctiilling evils and carnivorous plants that crave tiuman flesti! Avail, on disk (or the Apple II, II 1 or lie and Alari 800 or 1200 and Commodore 64. The planet Lexicon Is under attack! Letters of thie alphabet are falling from Itie sky. To repel Shem, you must be able to type the letters faster than they can fail. Be quick! An entire civilization is depending on your ski Avail, on disk lor the Apple II. or lie and Atari 800 or 1200, IBM-PC and Commodore 64 and on cartridge for the VIC-20. Critical Mass On Jan. 1st at 10:00 am, the U.N. received this message: "Good Morning, in exactly 9 days, the vifortd's S largest cities will be destroyed by thermal nuclear weapons." At 10:03 am, you received this assignment: STOP . . . THIS . . . LUNATIC! Avail- on disk for the Apple II. II I or Me and Alari 800 or 1200 and Commodore 64. Twerps The boldest space rescue ever! Defenseless Twerps are stranded on an aste- roid. You, Captain Twerp, are to board a Twerp- craft, blast through the Orblters, land safely and fescue your comrades. Beware of the Glingas and Tvirerp-eating Gleepnites! Avail, on disk lor the Apple 11. Il> or lie and Alan 800 or 1200. Pure Video Excitement! For Your Atari 800 or 1200, Apple II, II + or lie, Commodore 64, VIC-20 and IBM-PC Sirius. Twerps, Blade of Blackpoalen Type Attack and Critical Mass are trademarks oi SirJus Soltwaru. Inc.. 103G4 Rockingham Drive, Sacramonto, CA95B27 (916) 366-t195. All rights reserved. Apple II, II •. and lie are trademarks ol Apple Computer, Inc. Atari 800 and 1200 are trademarks ol Atari. Inc. VlC-20 and Commodore 64 are trademarks of Commodore Business Machines. Inc. IBM-PC is a trademark oi International Business Machines. Inc, Figure 4: Sample Type styles ft SAMPLE DOT-MATRIX PRINTOUT iDMercase descenders giJiP^q^y Highar quality text '.X csni^ 3^-t:.^d c: h S4»^ stcz t < CoipresHd chiracters offer iBre density per line fin si ternate- character set (typeface) n^O , E = MC - SUBSCRIPT AND SUPERSCRIPT This is a sample letter-quality printout lowercase descenders g.jrp>q>y tasks while the printer is printing. Almost all printers have a one-line buffer, but some printers have 4K, 16K, or even 64K buffers! Also, some manufacturers market add-on buffers that attach between your computer and the printer. The Interface Most computer manufacturers have a line of "official" printers. These are usually relabeled versions of other commonly available printers. Sometimes, the company that made your com- puter customizes the printer to add extra func- tions, or just a built-in interface. If you are buying a printer from a third party vendor, you may need a special cable or interface. The two most common printer interfaces are Centronics parallel and RS232C serial. Many home computers use a proprietary (non-standard) input/ output port and special cables. This does not lock you out from other printers if an "interface box" is available. You plug your computer's special cable into this "black box" and run a cable from the interface to the printer. Some interfaces also perform intelligent tasks, such as code translation, if your computer does not use the standard ASCII code {a convention for sending text as numbers). Print Width Most printers can print 80 columns per line, al- though some can squeeze in condensed characters in 132 character lines. Some printers have an extra- wide carriage. There are also 40-column and 32- column printers. If you plan to do word process- ing, you'll need an 80-column printer, since it matches normal 8'/2" x 11" paper. Forty-column printers aren't as common as they once were, 42 COMPUm June 1983 I since 80-column printers have become less expen- sive. If you are interested in screen dumps and program listings, you need a width equal to your computer's display width (22, 32, or 40 columns). IVIore On Daisy Wheels A daisy wheel printer prints by rotating a small metal or plastic disk with characters on long spokes, or petals. A hammer strikes the petal against the ribbon and paper. A variation on the daisy is the "thimble," where the petals are curved up into a cup, with the hammer in the middle of the cup. There are more moving parts and more metal and plastic in a letter quality printer than in a dot matrix or thermal printer. When you're shopping for a letter quality printer, see how many type styles are available. Also compare ribbon prices. Some daisy wheels can even superscript and subscript (roll the paper up or down half a line), type in boldface or "shadow," or even plot graphics using a period as a dot. Some lower price daisy wheels can mimic the features of their "big brothers," using the saiTie daisy wheel elements and ribbons. If you Want to add the valuable features of word processing, or want convenient hard copy at any time, a relatively small investment in a printer can change your whole outlook on your computer system. © TIMEX/APPLE Powerful, Professional, Quality Programs from Spectral Featuring these best sellers: FILE MANAGEMENT SYSTEM -You cremate and inanage all types ol Iiles for home and business [ncludes oplions lo enter records, edit locojAs, sort the file, search Ihe iile, and much much moriS. 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