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Second Class Postage Paid at Menlo Park, CA Address Correction Requested
93065JOHNSB09 01 2251 BYRON JOHNSON MY81 356 LAGUNA TERR SIMI VALLEY, CA 93065 FOR THE IMAGINATIVE SMALL COMPUTER USER! VOL. B NO.4 ISSUE 43 JANUARY - FEBRUARY 1980
ALSO PUBLISHED BY PEOPLE'S COMPUTER COMPANY: DR. DOBB's JOURNAL Computing & of COMPUTER Calisthenics & Holistic Health Dr. Dobb's Journal is a highly respected reference journal which fills a unique and Orthodontia solid niche within the microcomputing world. We publish discussions and examples Send in this form or a facsimile to start your of general purpose syst em tools, articles on subscription to Dr. Dobb's Journal. legislation or trends affecting computerists, ------OROERFORM------· a consumer watchdog column, as well as a SUln my subscription to Dr. Oobb', Journal. variety of monthly columns designed to 10 iHu", $'Styr. I$S off Ihe n_Htlnd price). guide and help readers wend their way D Check InclOMld D Bill me through the confusion of a new and bur· Name ______geoning industry. Addrell ______
Recent issues have included : • Growing, pruning City, State ______Zip __ and climbing binary trees with tiny·c • Selecting business software for microcomputers • An inter Sign8lu" active timeshared operating system for the 80aO Ple_ inquire about foreign IlItM. Send order to: • A critical look at the MC68000 • A zao -ZAP People's Computer Co., Box E, 1263 El Cwnlno, disassembler • Converting a·bit memories to Menlo Plrk, CA 94025. 16-bits OS I BASIC for the KIM·1 • Let your C7 computer speak ASC II Volume 8 Number 4 SUBM ITTING ITEMS FOR PUBLICATION STAFF January - February 1980 LABEL everything with your name, addren and the date; tapes should also include the EDITORS program name, language and system. TYPE text if at all possible, double-spaced, on 8~x Bob Albrecht 11 inch white paper. DRAWINGS should be as clear and neal as possible in black ink on white paper. Tracy Deliman Don Inman Special Features lISTI NGS are hard to reproduce clearly, 50 please note: Ramon Zamora • Use a new ribbon on plain white paper when making a listing;we prefer roll paper or 8 COMPUTING FOR HEALTH AND EQUALITY by David J. Hall fan-fOld paper. PUBLISHER • Send copies of one or more RUNs of your program, to verify that it runs and to Willard J. Holden An innovative application of the PET provide a sense of how things work- and to motivate more of us to read the code. RUNs ASSISTANT PUBLISHER 12 HOLISTIC COMPUTING by Tracy Deliman should illustrate the main purpose and operation of your program as clearly as possible. Sara Werry Proposal for a personal health data system Bells, whistles and special features should iust be described jn the documentation unless they're particularly relevant. PRODUCTION MANAGER 16 THE PRESTODIGITIZERtm TABLET by David D. Thornburg • Make sure your code is well documented-use a separate sheet of paper. Refer to Carole Cullenbine Train the PET to read portions of code by tine number or label or address, please, not by page number. When ARTISTS 20 TI GRAPHICS & ANIMATION : PART 2 by Ramon Zamora writing documentation. keep in mind that readers will include beginners and people who Watch Mr. Bojangles dance may be relatively inexperienced with the language you're using. Helpful documentation I Aleeca Harrison annotation can make your code useful to more people. Documentation should discuss Ann Miya 24 GAMES TO PROGRAM by Herbert Kohl iust which cases are covered and which aren't. A !anguage puzzle circa 1879 Judith Wasserman • If you send us a program to publish, we reserve the right to annotate it (don't worry, pg. 32 32 FORTRAN MAN by Todd Voros and Lee Schneider we won't publish it if we don't like id. TYPESETTERS Is Genera( Wirewound being SAVEd? • Last but not least, please try to limit the width 01 your listings: 50-60 characters is Phyllis Adams ideal. Narrow widths mean less reduction. better readability and better use of space. 42 SEE WHAT YOU HEAR & HEAR WHAT YOU SEE by Herb Moore Gavin Cullen Last in the series on music with the new Atari LETTERS are always welcome; we assume l!'s OK to publish them unless you ask us not Laura Mendell to. Upon request we will withhold your name from a published letter, but we will not PROOFREADER publish correspondence sent to us anonymously. We resarve the right to edit letters for purposes of clarity and brevity. Nancy Haubach Articles CIRCULATION MANAGER 25 PET READING PROGRAM by Eric Sevcik and Jim Sevcik ADVERTISING Michael Madaj Tutoring the reading disabled person ADVERTISING space is lIVaiiable in this publication. Please direct inquiries to the SPOT EDITOR 29 NEW DIRECTIONS IN NUMERICAL COMPUTING by Harry L. Pruetz Advertising Manager, People's Computer Company, Box E, Menlo Park, CA 94025. Harry Saal Making software into hardware (415! 323-311 1 PROMOTION MANAGER 34 AN EXTENDED BASIC " IF" FACILITY by Graham K. Jenkins SUBSCRIPTION INFORMATION Betsy Roeth pg. 25 A pre·processor handle nested IFs U. S. RATES FOREIGN RATES 40 BEATING COMPUTER ANXIETY by David D. Thornburg & Betty J. Burr And a spe<:ial thank, to all the othar Nothing can stop you now 0 $10/1 yr. (6 issuesl Payments must be in SUS drawn on a folk' at People's Computer Company: 45 A NEW ALGORITHM FOR CHESS by David Chelberg and David Watters o Retaining subscription @$25 US bank. Delia Daniels, Grant Groberg, Erica Part V: Middle game strategy ($15 tax deductible! o $17 Canada/Mexico First Class Sanders, Ann Merchberger, Nette THE OUTSIDE CONNECTION by Doc Plumber and Son, Ink. o Sustaining subscription@$100+ o $23 Rest of World Airmail Cekansky Wang, Sahnta Pannutti, 49 ($90 tax deductibla! 0 $14 World Surface Mail Ellan Markoff. S·100 compatability for the TRS·80 o Lifetime subscription @ $900 + ($700 tax deductiblel Please allow 6-9 weeks fa. your first Delivery of foreign mail is slow and unre· RETAINING SUBSCRIBERS If Games & Stuff i$Sue to arrive. liable. We strongly advise airmail. 7 CRYPTARITHMS SOLUTIONS by John Davenport Crehore Algorithmics, Inc. 22 CAPTURE by Mac Ogelsby BACK ISSUES David R. Dick A game for the PET Mark Elgin $2.50 each; $3.00 each: ... 34 39 8080; TIC TAC TOE by L. Barker VoI.6,Nos.1,2,3,4,5 l Outside the U. S. John B. Fried VoI.7,Nos.3,4,5,6 Play the game by formula Vol. 7, NOli. 1, 2 VoI.8,Nos.l,2,3 \ add $ .50 per issue. Scott B. Guthery W. A. Kelley 52 CHAINWALK by Grady Early Have your computer pull your chain FOREIGN DISTRIBUTORS OF RECREA TlONAL COMPUTING Brett Wilson William M. Richman II 56 PROGRAMMING PROBLEMS by Bob Albrecht and Don Albers LP Enterprises, B/ll Cambridge Hou$8, Cambridge Ad., 8arking, E»I!x lGll BNT, UK; Perplexing puzzles for you to ponder Elec1ronic COnCepti PTY Ltd., 52-5B Clarence St., Sydney, NSW 2000, AUSTRALIA; 58 SPOT; THE SOCIETY OF PET OWNERS & TRAINERS by Harry Saal RS-232, 186 Queen St .. W. Toronto, Ontario M5V lZl, CANADA; ASCII Publishing, SUSTAINING SUBSCRIBERS 305 HI TOAIO, 5-6-7 Minami Aoyama, Minato-Ku, Tokyo 107, JAPAN; Ing. W. PUblications, products, POKEs, and ~pologies Hofacker, 0815 Holl.kirchen, Lindenst•. 8, WEST GERMANY; Hobby D,tl, S200 12 Bill Godbout Electronics Malmo, SWEDEN; Computer Stora, P.O. Box 31·261, 22B Millord Rd., Milford, Auck· Byte Publications land, NEW ZEALAND; Sytteml Formulate Corp., Shin-Makicho Bldg. 1·8·17, Yaesu, Paul, Lori and Tom Calhoun Departments Chuo·Ku, Tokyo 103,JAPAN. Louis R. Patzke 4 EDITORS' NOTES & LETTERS Printed by Nowels, Menlo Park, CA pg.20 5 LETTERS Recre8tional Computing (ISSN #0164·5846) is published bimonthly by People's Computer Company, 1263 'EI Camino Reel, Box E, Menlo 55 REVIEWS '.'" Park, CA 94025. People's Computer Company is a tax ·exempt, independent, non -profit corporation, and donations are tax·deductible. Secood COVER by David Damaron 60 PROGRAMMER'S TOOLBOX cia" postage paid at Manlo Park, California, and additional entry points. Copyright © 1980 by People's Computer Company, Mania Park, 62 ANNOUNCEMENTS California.
2 RECREATIONAL COMPUTING JAN · FEB 1980 3 Notes
THE EDITORS' NEW YEAR NOTES Since Ollr main contributors are the NEEDS DENTAL SOFTWARE COMPUTING IN EDUCATION readers of RC, we would like to inllite It's a new year! Time to make our resolutions. and wish our you issuel on tile following topics: Games and Recreations; you to send articles alld programs, You I am the owner of a Radio Shack I am currently enrolled here at the selves a happy anniversary. n,;s issue of Recreational Com 6502 Processors; Simulations and Fantasy Role Playing; COli send us YOllr material now for TRS-SO. I presently have 32K, three disk University of Texas attempting to gain a puting marks the one year al/n;versary of the magazine's Leamil/g;and Music Qnd Art. We will be Fe-emphasizing games, consideration for one of the theme areas drives, and Ihe tractor feed printer. I am a degree in computer science. The nome change from People's Com pUlers. There were other recreation Qnd chal/enges in all upcoming issues, since you've ill coming issues. JUSI note in your cover general dentist, and would like 10 use the compuler seems the ideal means of chal/ges during the year. Louise Burton, one of the co-edi· indicated lhal s what you want most. We will focus our cover letter tllat your submission is to go iI/to computer in my office. In case you are eliminating much of the unnecessary tors at the time of the name switch, has left the masthead, age on five major micros- TRS-80, PET, APPLE. ATARI, the "LeanlinK" issue or the "Music and not familiar with the needs of a general portion of the educational system and and two new co-editors have been added. Tracy Delimall and TI99/4- with an increase in the number o/shorr pro Art" issue. Of course, you call colllinue dentist, I would like to do the foUowing: allowing intereSled learners more direct joined the stall with the Sept./Oct. issue; Doll Inmall joilled grams included. Our articles wil/ be user-oriented materfui to send us malerial on allY subject, as I) type patient name-screen shows access to Ihe subjeci mailer. Academia's us ill 'he NOIl./Dec. RC. Bob Albrecht alld Ramon Zamora, geared toward tile beginner through intennediote level. The dillersity is part of ourcharacler. name, address, etc., fmanc ial status, recall attempts al self-preservalion take no the other two co-editors, are still with us. magazine's cOlltent will be broadened somewhat to allow status, insurance information; 2) type more grotesque forms than in the COITl expansion o{ our readership. As a final 1I0re, we wish to thank the employer-screen shows all delails of pUler science department, I'm led 10 During the past year, several lIew features have beell added to people who have supported us in the past insurance plan; 3) aged receivables believe, after only two semesters back in the magazine: Programmer's Toolboxtm , FuturePlaylm, RC will halle a new look. 17,e cover will be upgraded to year both by buying the magazine and patient and insurance company; 4) ap school. Cryptari'hms, n,e Outside Connection, Games For You To glossy paper, which will add four extra pages 0/ conlenl to the by contributing material. We look pointment control and daily schedule; Program, and ollgoing tutorials for the Atari and Texas magazine and improve its appearance on the newstands. forward to providing you for another 5) fee list - A.D.A. code list; 6) insurance Yours seems like an organization with a Jnstrnments computers. We've brought you over 100 articles, year with a magazine that is one of the forms; 7) statcments; 8) daily. weekly. lot of the same ideas. I reside on the special features, and small programs dun'ng the past 12 New columns Qnd regular features will join the mLlgazine in mOSI content-packed periodicals on tire monthly, and yearly reports; 9) provision ethnic side of town, and was appalled to months. n,is material came to us from all over the world, and the coming year. With this issue, Bob Albrecht and Don market. As our nome suggests, we will for keeping track of production of learn thai Chicano children are not given was generally new copy not foulld in any other magazine. Albers inougurate a new challenge series, "Programming continue in the coming year to re·create multiple providers. any instruction in Spanish. (Time was in Problems," to mil throughout 'he year. Dave Thornburg the magazine with eaclr issue, while Texas that children were forbidden 10 Beyond all the nel\,'ness and changes, RC remains committed and Betty Burr are beginning a new column called "Com looking both to the past and the fiallre The system must be self· prompting, speak Spanish on school grounds.) My to goals alld principles that provided the motivation for start puters alld Society'" starting in the March/April issue of RC. for inspiration. As for the computing goof-proof, all data must be placed on idea is to have lessons in Spanish, as well ing the People's Computer magazine. and the People's Com part of our nome, Bob Albrecht has the disk as it is entered. Disk and hard· as subjects covered in school, pro puter Company Newspaper. the two precunon ofRecreation We will continue to report on the other projects of PCC, noted. both to us and to you 011 se~'eral copy backups mUSI be automatic. grammed into a system. Individual al Computing. Those goals lVere most SUCCinctly given by the such as ComputerTown. U.S.A. I. and PCNET. Computer occasions, "Computillg takes place in the studenlS could gel credit for completion, Dragon, Bob Albrecht, way back at the start of our company: Tot.l-7/ U.S.A.! is an innovative computer literacy project, mind, as well as ill machines . .. If you have this type of software, or are good for time on the games programs. sponsored and peopled by PCC personnel, designed to give interested in creating it, please comaci Computers are mostly used against people instead f!I1eryone in a town of 27.000 a c/umce to use a microcom Ramon Zamora Tracy Deliman me immediately. Keep up the good work. of for people, used to control people instead of puter. Bob Albrecht and Ramon Zamora, the initiators of the Bob Albrecht Don Illman to free thcm. It's time to change all that-we need project now have four computers installed in tile library of Slephen B. Katz, D.M.D. Robert Garvey a People's Computer Company. the town of Mellio Park, CA. Hundreds of kids have been I Hoover Lane Institute for the Advancement of validated to lise the machines, and there have been numerous New City, NY 10956 Absurdist Thought So pec was fOllnded as a non-profit educational corporation, "open classroom" sessions held at the library. The project (914) 354-1181 1III Willow Street lVitll the aim of helping to put computers into the hands of has elljoyed a great deal of local media coverage. and promises Austin, TX 78702 I)eoplc. Recrealional Computing is one publicatiol/ of PCC, to gain some lIatiOllal attelltion. THEY LOVE US! Olle vellicle to educate people about emerging computer tech nologies. and make that technology both useful alld el/joyable PCNET, Personal Computer NETwork, is another project I wanl to congratulate you on your COMMENT ON PASCAL VS. BASIC for people. A s the first periodical in the field of personal of PCC PCNET oilers personal computer-based electronic November I December issue of Recrea computing, RC is concen/ed with the fumre of computing mail software. RC plam to publish infOlmation on how tionol Computing. We, the eighth graders Just a note 10 say thai I am amazed that and 1I0w it allects the individual. PCNET works, some of the telephone protocols that are being of Whitehall Middle School and myself, no one has yel pointed out that Jim used, and other aspects of this unique "grassroots" hardware/ have acquired three PETs by car washes, Day's BASIC fragment (Leiters, May RC's readers are oftell its authors-its readers are its best and wfrware project. dances, suppers, and we re jusl beginning June 1979) uses a multiply, and will most frequent COntriblllors. RC exists so our readers and the to write music when Alfred Bruey's execute much marc slowly than any magazine can enjoy personal, sociDl, and technological growth; RC will also be conducting a survey of our readership by direct arlicle appeared. other PASCAL or BASIC fragmenl lhat we Te also a fornm for tile interchange of ideas and issues. mail. The goal of the survey will be to find out who you are has come under discussion in the RC a"d its readers halle been insfnlmental in fostering the and what you do, and what you want to see ;n your maga Keep the articles on the PET coming! "PASCAL vs. BASIC" articles. growth of microcomputers as an industry and a personal zine. The survey will be an invitation for a randomly-selected tool. number of readers to participate in building and directing Also, I am interested in exchanging tapes Still working on Wylbur-Pilot, and you'll the future growth of the magazine. As we have said. our best wilh any junior high teachers who would all be sorry when the technocratic empire What about tile fllture? The "ext year for RC will be material comes from our readers. We want to hear from all like 10 exchange. crumbles. excitil/g. Each issue will have a specific theme. We71 bring ofyou as we move into the future together. Gary W. Dade Robert Solomon Whitehall District Schools 181 Baltic Streel J Whitehall, Ml 49461 Brooklyn, NY 1120 I • RECREATIONAL COMPUTING JAN .FEB 1980 5 HUMANlZlNG COMPUTER GAMES
So you play Star Trek and have logged a I am suggesting the interactive game I have read "The Lord of the Rings" and If we design a game where more than one put an end to the human race. We should what is it most useful? Are there other thousand hours as Captain of the U. S. S. where the computer is a moderator and did enjoy it, but it is not real. To hide in human player is involved then the com all try to bring in a new group of games materials supporting its use in class Enterprise, but you need to keep a com scorekeeper only. If you have played this type of simulation is not realistic. puter sho uld act as the moderator and the designed to make a better world for rooms? Is PILOT in any way related to mand sheet handy lest you forget # 9 is Brett Tondreau's Galaxy II, you know Rather than waste my energy fighting scorekeeper. It should aid any and all humanity, not make it easier to destroy LOGO? self-destruct. Why? You say it takes more what I mean. It is a space simulation fantasy with science fiction, I use my players in the same way. man. memory and memory costs money. To where each player starts with one colony time on science fiction because I prefer to Additionally, I would like to know about use words to replace the sequence of and from one to five ships, and through deal with Utings that could happen in Sometimes we need to stop and see where Uve long and prosper. your Society for PET Owners and number codes would use a little more playing expands his holdings. The idea future time. we have been and where we are going. We Trainers. memory but for command recognition is to defeat all other players and rule the may find that we have missed the point Robert Howarth, Jr. it might be well worth it. I have never galaxy. You play one turn per month and In pondering this I realize some people and if we stop and look, we may find our RFD#lBox36 heard Captain Kirk order his action get a tolal printout of your own actions will say that I am wrong too. OK, not all way to the right track. Star Trek has Usbon, NH 03585 Thank you! this way. Maybe it has not been done and encounters. (If you want more data science fiction is possible but it is far served us well but it should be replaced Beth Lowd often because it would take away some of send 254 to Brett Tondreau, P. O. more realistic to imagine oneself as a by a new more human and civilized game. Specialist, Computers in Instruction the fun when someone new sits down at Box 7968, Van Nuys, CA 91409.) conunander of a space ship, or ruler of Of all of science fiction. Star Trek is the Lexington Public Schools our fancy machine to try his luck at the a space empire that it is to place oneself most humane. yet our game is barbaric WHO CAN ANSWER? 9 Philip Road things we call fun. Since Galaxy II is on a big machine it can in the fonn of some hobbit or wizard. with murder and death. We should strive Lexington, MA 02173 only serve to give us ideas. Most home You may then ask, "What aboUi ESP?" to end this type of game and use our time Please send me information aboUi PILOT. Perhaps we would get more friends into systems have but one terminal and most The possibilities of ESP and the powers to make games that help us to know How can it be implemented on a PET? n,e Society for PI:./ OWI/ers and Trainers the computer hobby jf our games and of our games are played alone or with one of the human mind are all accepted. As other people better, and to understand On a PDP-S? On a PDP -II? How costly is a tmly unique society, comprised of programs were more human. It could be other player. We could use a modem to our horizons expand I am sure we will them. is it? How much time does it take to everyone who considers themselves a PET as simple as finding a new language fo r tie several systems together or even design find stranger things yet. Part of the fun in receive it? How much training do teachers user. 11lere are 110 meetings, no member our machines or even to use the one we a game where players are selected at Fantasy games is that they do not foll ow You may say that it's only a game. Yes it need to use it with students? For what ship dues, no elee/iollS ... in fact, 110 call BASIC to better advantage. As it is, random and we place our turn on cassette the nonnal rules of time, space and the is, but war and politics can be considered reasons was it developed? Is there organization. Actually, it is the SPOT we have programs that are far from or disk and forward the media to the next universe. games, too. Such games could very well research supporting its usefulness? For column by Harry Saal. understandable to outsiders. While this is player. fine with the simple Lunar Lander, it isn't While half of you now hate me and the good in a fantasy game or simulation. We could take a survey of a game like other half says right on, I feel another Galaxy II and use the data to design a group looking and saying games are a I think we all can agree that a short pro single player game that could present a waste of time and serve no useful gram with a lot of remarks and advice is number of different playing styles, thus purpose. Remember, all work and no play Cryptarithm Solutions (1979) far more enjoyable for the newcomer and giving it a more human character. With a is the reason so many people crack. for ourselves. A program with a person disk system many different playing slyles Enough people do play games to make Number/Leller Correspondencc ality is well -liked and is played more than and plots could be stored and accessed as this subject worth talking about. RCJ55Ue Puule No. 0 , 2 3 4 5 , 7 8 9 plain data-type programs. If you made needed. Even the sequence could be B two lunar lander programs, one with the What now? Well , first we must fmd a No. 40. July-Aug. , C random. 2 T bare bones and anOlher with remarks like good language for our games, or to design • 3 B Y C A r "You made a new crater _ KM deep," Interaction between players in Galaxy II a new one to handle the special things we 4 K C "B r A there would be little doubt which will get is what makes the game enjoyable. This is want to do in our simulations. We need 5 "D " II K the most use. why the new crop of war games and some priorities: 1) we need a good con , D "E II N T U S y A 8 fantasy games has grown to a reasonable versational language like PILOT; 2) we 7 8 U Y E S M L N A • In playing against the computer we often portion of the hobby and craft industry need some math to cover calculations 8 E 8 T D L W U C play against the perfect game or a game in 1978. Any game played with other and scoring; 3) if graphics are to be used No. 41 . Sept-Oct 9 " "L S A 8 where the machine will make a mistake so people is better than the perfect game then we need a good fast way of imple 10 "C D F K T A B U C • N E you can win. This is why Star Trek is played by the computer. menting them. Y D " E II L S •T U Y better-it is not played against the com "12 A 8 " puter but instead is played against the While I do not care for fantasy games as In the actual game itself we need many clock and against an enemy that follows compared to science fiction games, I do things to make it mean something. It firm rules. It would be better still jf the think that games like Adventure are done must: 1) have personality; 2) be one that n/ere are no Cryptarithms in this issue of Klingons were controlled by another well. These are some of the best games· we can win; 3) have a variety of char RC. Look for Cryptarithms again ill the player rather than the computer, and also currently in use on microcomputers. acters; 4) have more than one playing Marcil - April Games &: Recreations issue if they had movement within the entire Before I get all those fantasy freaks mad strategy; 5) be easy for beginners to play. of tile magazine. galaxy instead of just one sector. at me , let me explain.
JAN .FEB 1980 1 6 RECREATIONAL COMPUTING An Advance in Humanistic Computer Use Modem orthodox medicine has accepted WHAT HAS COMPUTING the use of computers very well, perhaps TO 00 WITH HEAL TH1 toO well. It seems that M.D.s have toeen discouraged from using their own hands There is no doubt that computing has because of the malpractice insurance more impact on our lives today than ten problems implied in touching a patient. years ago. We have witnessed the advent There seems to be an over-reliance on of many kinds of calculators, digital the use of sophisticated tools in modem watches and personal computers. The orthodox medicine; it is apparently con· purpose of technology should be to sidered more scientific to test and meas· contribute to our comfort and well· ure than to feel. These complex tools being. With all the material resources and instruments provide only second· available today, we have little excuse HEALTH ~~ill) EQUALITY hand knowledge though, not the direct for being unhealthy, except that confu· experience of "putting one's fmger on sion tends to be rampant in a surfeit of the problem" that many of the holistic resources. Computing of the right kind approaches encourage. While the wonder· counting what really matters, evaluating ful, detailed pictures being produced the data counted and verify ing the pro· by the latest computerized tomographic grams that process that data- are activ BY DAVID J. HALL, scanners are surely very useful to the ities that can help put order in our lives, M.Sc. (Eng.) D.l.e. brain or heart surgeon, and are a triumph contribute to clarity and thus lead to of sophisticated computerized techno· health. More specificall y, we can use a logy, most common health problems can David Hall is a senior research engineer computer to evaluate the details of be solved by a more simple and direct who not long ago tumed holisn'ca/ly We readers of Recreational Computing basic factors related to health, such as approach. This approach uses the trained healthy. Here, he presents a refreshing do not need to be reminded how eco diet, exercise, cleanliness and rest. human hand, as in roirmg, for exam,lle, and unique approach to both health and nomical the price of computing has become over the last several years, so that a system of deep myofascial manipula· low-cost computing can take many com compuling. David parallels many of the tion, or massage . ideals for health that come from the vast computing power is now available at plex health factors into account, and can the domestic level. Perhaps health is our be accessible to a large number of users. holistic health movement with some of These are the two extremes of health the pn'nciples involved in computing. He most precious asset, so it is natural for a After reliable software becomes avail computer engineer like me to ask : what care: first the remote physician does able, family members should be encour views computing as a mind functioll as not physically contact his patient, but well as machine function, and shows the can my computer or my thinking pro aged to use a home computer for health cesses do to promote health? Can health rather subjects him to many tests by checkups. It is likely that we will soon relevance of these ideas in computing instruments and to swallowing much for health. On the practical side, David be logically deduced and calcuJated, or is fmd many software developments in the it a matter of heredity, good fortune medication (with numerous side effects) area of domestic health, so that com· describes his own computer programs of recent invention by sophisticated and luck? As a senior research engineer puting will eventually be of significant on health and equality. Hopefully, chemists. Second, there is the more in· with 20 years experience in electronics benefit to social heahh. David:t explorations in this area may timate healer, who personally observes generate imlo~'ative programming ideas and computing and as a professional health worke r for the last 6 years, I and methodically contacts all of his CHOICE OF COD ING among our readers. VIe author's address client's important parts, and calls upon have given these topics much thought. CONTROLS THE MACHINE ;s P. O. Box 9487, Stanford, CA 94305. the client to heal himself by releasing - TD Just as there is a new trend towards low· ACCORDING TO HEALTHY DESIRES cost microprocessor technology in com undue stresses. puting, there is also a new trend in health. In running any form of computer, an A good way to begin is with definitions. The small computer, being accessible Computing means literally ·'thinking important issue is how the coding of domestically, is a good "middle -ground" one's wishes for certain characteristics with," that is, thinking or figuri ng out Holistic health is a recent popular trend tool. II does not replace the skilled of inpllt, proceSSing, and output can be with a tool such as pencil and paper. that seems unorthodox compared to the human hand, or the highly technologized easily accomplished. Operation code$ Health is the condition of the human approach of the established M.D. The physician, but the computer is able to (OF'CODES) for each type of computer body, mind and spiri t that enables it to basic idea of holism (a concept formu process effectively some of the data defme "machine-language" properties. perform its vital functions well. Thus lated by J.e. Smuts, the fonner prime concerning the simplel health factors. "computing fo r health" is using our most All other high-level languages invented minister of South Africa) is that the Many simple peripheral mOnitoring de· modem tool, the computer, to maintain individual is treated as a whole entity, for ease of human programming, must be vices for measuring bodil y performance coded -down to machine language before and improve our performance of vital equal attention is given to all parts of might eventuall y be devised for connec functions. "Equality" is a term used in execution. A "healthy" machine is one the human being, including body, mind tion to a home computer. For exanlple, mathematical equations, arithmetic and which realizes the desired input , proces- and spirit. Orthodox medical treatment, perhaps a low-cost heartbeat monitor computation. Equality is also used as . sing, and output fWlctions, just as a on the other hand, concerns itself with for displaying blood pressure may s.)On a social ideal and it implies balance, an healthy person is one who realizes his gross pathological problems that doctors be available for connecting yourself to important property of health. The prac own desires. Then, just as a healthy at · seldom recognjze unless they have your home computer. In this article, we tical application of equality in social titude is supported by good posture, measurable material effects. Orthodox will examine how we can input data systems a well-constructed and reliable computer is currently important in the treatment · js administered by highly via the keyboard of a small computer ideals of equal opportunities for men specialized doctors practicing in non· program needs good structure as in (in this case, the PET), so that valuable "structured programming." and women, and for all races. The overlapping fields, such as heart surgery information about maintaining or improv healthily-used computer should maxi or ear -nose ·and -throat specialities. ing health can be computed and displayed. mize the whole function of living.
8 AECREATIONAL COMPUTING JAN ·FEB 1980 9 COMPUTING THE SOL.,UTlON dress- coding of our bodies, since food beings, our constitutional health applies TO A HEALTH PROBLEM c10tlling is an arrangement of materials both to our individual and collective functions that men and women perfonn about the body, fitting we!! , and serving bodies. Whatever social classification we can be evaluated with respect to equality "Perhaps a low -cost Let us assume that you have a small the function the human body is per are born into, we do not expect ideally by observing what function each indi heartbeat monitor for vidual perfo rms, for example, washing computer that is suitable for figuring forming.) to be penalized or discriminated against displaying blood pressure because of it. Any individual automatic dishes, preparing food, repairing motor out solutions (S) to health problems, may soon be available using data (D) , and suitable programs (P). THE MEANING OF EQUALITY, ally belongs to both a racial and sexual vehicles, gardening, etc. Mathematically. we say that the solution NUMERICALL Y classification, but these specifics should for connecting yourself is derived by evaluation of the function neither penalize nor restrict liberated The coding of machine instructions is to your home computer." P(D). Or, the solution is equal to the [n the numerical sense, a reliable com behavior. like the soft-ware of the human body, , program running with data. (See Figure puter should always give the correct that is, computer codes and dress codes I for a block-diagram or flowchart of answer in testing for equality. Naturally, Do you have the freedom to act beyond affect the behavior and functioning of SUMMARY OF HEALTH-RELATED this process): there are limits to the accuracy of any your classification and stereotype bound· intelligence, whether artificial or real. PROGRAMS FOR THE PET computer. These limits are demonstrated aries? For example, if you are a man, Dress coding is usually decided by the S = P(D) fashion designers and clothing manu for the PET using the "Equality" cassette would you feel comfortable washing The subject of health is so vast that facturers, or by the public service or Although this equation is conceptuaUy tape. On this tape, I show that PET's dishes, or doiTlg other traditionally , covering even a small part of it may ganizations for which formal and recog • very simple, it has introduced notions BASIC makes an error in testing for womanly activities? Or, if you are from a require a library of applicable programs. nizable uniforms are appropriate. (See and notations that are the basic symbols numerical equality, but this is not usuaUy black family, can yOll choose your home The first three I have been developing used in computation. Because this is an a serious error. The program tests the in the white suburbs? Equality tests my paper, listed in References). are: equation. to fully understand its meaning, "mental" health of the PET system itself, some of these ideas as they apply to your we must understand the notion of equal showing that it should not always be daily life activities, and makes a light PROGRAM PROVING Health. This is an instructive program ity: both in its strict numerical sense, . believed, and the mental health of the hearted judgment as to your sex, based that presents some fundamental state and also in its constitutional sense. As a user concerning arithmetic precision upon your answers. The important goal in using computers ments about health and asks some conscientious practitioner of the holistic related to notions of equality. For for health is to be sure that the program's questions about your status and health discipline of rolling, I interpret balance example, when we RUN the follow· Society has placed upon men and women results really do contribute to heaJth factors. It is based on the "nonnal and equality of shapes. In rolfing this ing statement: a need for clothing. Our natural state rather than cause damage through error. distribution" curve of de Moivre. concerns placements of masses of hWllan is without clothing, therefore clothes Any heaJer, psychiatrist, M.D., yoga tissue , while in computing, it concerns IF 99.99999999'" 9<) .999999999 THEN should be considered from the aspect teacher, rolfer or other heaJth practi Unfortunately, we have not yet been the computational limits of numerical PRINT "TRUE" of health as we\l as from the aspect of tioner must not cause harm, but should able to fully harness our newly acquired equality. Also , we must consider its the PET prints TRUE, even though the fashion. For example , in Victorian times contribute to health. Therefore, results • and immense computing power for health opposite, inequality, which would be second number has one more nine after women often fainted because of tight of treatment must be constantly checked programs in the home, The basic elements termed discrimination or classification the decimal point, which makes the corsets. Similarly some men today, re and verified, as our ultimate measure of health are cleanliness, diet, exer in social or mathematical terms. The pro second number larger. The problem arises strict themselves with tight collars and of results is success. The deepest kind cise, and rest. Each of these elements gram "Equality" that I have developed because the machine can only deal ties. Clothing may differ according to sex of success, however, is felt internally. • should be examined by each individual for the PET covers both these social with JOdigitsofprecision and it "forgets" differences but if socieTY is balanced and We are certain that our computing in the family once-per-week initially, and computational aspects of equality. digits beyond that. It should signal some equal, it wi! not discriminate against machine does not feel its own degree of but if illness occurs, then a daily check (See later description.) In the sections kind of syntax error, but does not do the free choice of clothing for any certainty, it merely acts without cons up is better. A checkup begins with your following, several computing ideas that that. body, because of its sex. If society is cience. Evaluation of the success of a current status. relate to health or equality are discussed; computer program for health then, is healthy and balanced, it will also be seen The questions asked by the program are we see what happens ill testing for THE MATHEMATICAL SIGNIFICANCE to be balanced by its appearance and to be trusted to the human judgement of the user. the simple physical variables such as age, numerical equality on the PET. Socio OF EQUALITY APPLIED TO this implies that a census or COUllt of the weight, sex and height. Your particular sexual roles in everyday living functions SOCIO-SEXUAL CUSTOMS frequency of the two basic garments measurements can be compared to a are examined for you or any family (skirt or pants) on either sex, will be Health and intelligent behavior is a vast and mysterious topic. We can mani healthy ave rage . This data comprises member. Other ideas about the arrange In the constitutional sense , equality is observed as approximately equal. Since your current status or stature. Questions ment of material tissue and socio-sexual connected with freedom of opportunity function and structure are related in a pulate factual information about our health, and can give it our attention, are asked about your lifestyle in relation roles are present. (lllis touches on the and equal rights. Because we are social complete, holistic consideration, the to these four basic elements and a score and thus we may improve it , since atten is computed for each of these elements. tiOIi relieves tension. There may always be a somewhat unsatisfactory or in The total score is a measure of your DATA LIST RUN complete feeling about running a specific health. (declares entries of observation data (gives list of program (PI statements (gives output or results of program health-related program on a small com Health introduces itself as shown below: (D) to be recorded and processed) and data) running its process to solution (S)) puter when the user holds the whole concept and detail of health in mind. PROGRAM OUTPUT It becomes the responsibility of the ~ HEALTH .... IP) health program user to constantly question ~ lSI .,.. the health program's validity, just as AN INTERVIEW BY S = P(D) the computer questions your validity DR. PET TO in checking your health when it asks PROBLEM SOLUTION RESULT DIAGNOSE YOUR you specific questions. What have OBSERVATION r HEALTH MEDITATION ACTION devised is a series of health-related DIAGNOSIS MEDICATION RE-MISStDN computing exercises for the mind, via HEALTH IS THE COMPLETE the keyboard and disp[ay, I hope these COMBINATION OF Figure 1 The Three Elements of Computing in Several Disciplines contribute to your health, but bear in OPPOSITES, AS YIN mind that they cannot supply the magical AND YANG. ingredient that comes from right living 10 RECREATIONAL COMPUTING in tune with natural order. JAN-FEB 1980 11 BIOFEEDBACK Galvanic skin response is the natural electrical resistance of the skin. Changes The science of biofeedback already in this response are very subtle,and are an accompl ishes much of the task of sensing indication of arousal of the autonomic Developing that awareness means and recording physiological data. Biofeed· nervous system or of stress. A change in EqW1liry. This program deals with the observing, on a daily basis, several kinds back is most commonly used for the pur· skin temperature is also an indicator of notions of equality and discrimination. of physiological responses which are pose of learning to voluntarily control stress or discomfort, as most of us know In BASIC terms, = is the symbol Lsed HOLISTIC known indicators of real bodil y changes. certain physiological and mental pro· from having experienced cold hands at a to signify equality, whereas <> signifies These changes are associated with cesses that were previously believed to job interview or similar situation. its opposite, inequality. Tests of the physical and mental activities, diet, mood be entirely involuntary. When an indio limits of discrimination of equality in or psychoemotional state, illness and vidual is connected with the biofeedback Brainwaves are more complex than most the PET are given , and its shown that fatigue, and attentiveness. If we machine, physiological processes and of these processes. They come in some of the PET's conclusions are faulty, thoroughly understood these responses responses are measured and fed back to different rhythms-alpha, beta, delta, indicating that it is failing in certain areas in ourselves and could monitor them the person. Then, with many hours of theta and others-and are related to dif· of "mental health." COMPUTING every day, we would be able to plan our observation of these responses and with ferent mental states. Alpha is a relaxation work-productive and creative activities the guidance of a trained practitioner, state, beta is a mentally attentive state, Note in the test for equality, that MAN < with much greater efficiency. Imagine an individual learns some voluntary delta is a condition of deepest sleep and WOMAN , but that MALE> FEMALE. how much more you could achieve and control over these processes. The essential theta is a state of creativity. Brainwaves Similarly, BLACK < WHITE and NATU create if on each day you knew idea in biofeedback is to sensitize our also vary with different stimuli such as RAL > CULTURED. Although these concretely which of a multitude of self·observation abilities and learn self· light, sound and touch. terms are ones of social equality, the activities you were best suited to under control. computer does not know the meaning take on that day. Patterns of muscle tension, particularly of them, only their alphanumeric pre The biological processes usually measured facial muscle tension, are correlated with cedence based on the ASC II code. How To a certain degree we already observe in biofeedback training are skin tempera emotions which may be felt but not ever, it is useful that the machine can ourselves and sometimes make changes ture, galvanic skin response (GSR), expressed. Changes in rapid eye move order any word·pair you might like to in dietary or other patterns so that we brainwaves, muscle tension and eye move ments also may be associated with type as a test for equality in this way. will function better or feel better. But to ment. These responses relate to emotional emotional feelings and stress or nervous· make such detailed observations everyday changes, nervousness and attentiveness. ness. Measurements of blood pressure Telindex. This program is being de as would be necessary to really maximize Each of these processes is affected by could also be added to our program, as veloped for health referrals. It will list our productivity and creativity would changes in the environment, or by this response is certainly an indicator of specific health professionals and or· require years of training and careful changes in the physiological or conscious· the range of comfort to stress. ganizations under their general headings, BY TRACY DElIMAN self-observation. It seems obvious then ness level. Stress or an altered mood, for for example: M.D., podiatrist, rolfer, that a re li able electronic device would be example, can produce a response in one THE HOLISTIC COMPUTING PROCESS acupunclUrisl , dentist , elc. (These profes This article describes the basics for a more accurate in objectively assessing, of these areas. sionals will have paid a small fee to be user· oriented computer program on recording and correlating those subtle The user would first need to run a battery listed on this tape, and they will be per holistic health, a program to help anyone physiological responses. of tests on herself in all six of the sonally recommended as being excel maximize their efficiency and health biofeedback areas. These tests would lent practitioners in their fields.) Tel throughout daily activities. The idea Out of these musings and desires a pro· establish average data points for normal i/ldex also has a more general function was inspired by my own studies in gram idea has emerged. A simple bio· response modes; that is, when the indio as a telephone index program that stores holistic health and by David Hall's feedback machine would be interfaced to vidual is calm or in an otherwise "normal your frequently·used names and tele article in this issue of RC. - TD the computer (with an analog to digital or feeling good" state for that person. " " " phone numbers so that the number of the - , converter to change the data to numbers " .'-...t-+_ .,- The accumulated data would become person you want to call can be instantly One of the visions that emerges from the that the computer can use). The program referent points for future tests run in the " .' displayed on the screen. The input " humanistic growth and holistic health itself would include a personal profile as daily monitoring program. The user could required to find a number is minimal, ", movements is the image of a kind of data base, detailing standard health data, see where they stand in any given test by since usually the fi rst few characters .o• , " "super being." The vision varies some a list of the individual's work· productive comparing their daily score to their stan of the person's last name will uniquely " what, but basically this human has nearly and creative activities, recreational and dard score (or referent point). identify that person. The program is boundless energy, is highly productive relaxation activities, and dietary patterns. intended to be run continuously while and creative, can handle responsibility This program would enable the user to Next, the user would enter known the PET is not needed for anything clse. and social demands well, and is peaceful connect with the machines and enter personal health data, for example, high A User's Guide for the Telilldex Program and content in personality. Sounds ideal? daily health data directly, have these blood pressure, prevalent disorders, supplied with the cassette tape, will Recently, many people are jogging more, scores correlated wi th standard health susceptibilitY to stress, etc. With test give further details of the program. cutting down on coffee, sugar and fats, scores (for that person), then get a scores and personal health data together, ..... meditating, and becoming more caring reading of which group of activities 'She could establish a range of acceptable ,."M'_'· '. REFERENCES , ~ .- ..- "' -- in their personal relationships. They're should be followed that day. The pro scores for each of the various tests, and also becoming more productive and gram would also display suggested relaxa: a range of unacceptable scores, or scores I. Wischnia, Bob. "Rolling" in Runne~ ' more content with their lives. tion activities and dietary schedule to that indicate poor functioning or undue World , January 1979. complement the selected productive stress. 2. Smuts. J.e. Holism Qnd Evolution. New As I watch these events, I realize that the activities. This holistic computing process York: The Vikin8 Press. Compass Books vision is actually not impossible to will be further elaborated, but first a Edition, 1961. Lastly, an assessment of the person's 3. HaU , David J. "Advantages and Disadvan achieve, but that getting there requires a closer look at what's involved in biofeed psychoemotional state could be entered, tage s of Various Form s of Body Coverin£" gradual increase of awareness of all the back that would be applicable to this using a sliding scale of 1 to 10, repre- (available from the author). details of one's health. program idea. negative to positive states. For " RECREATIONAL COMPUTING JAN ·FEB 1980 13 more precision, each number could The final data area to be entered into the In the active mode, the user still goes 1 identify particular emotional states char program is dietary patterns, The informa through the process of connecting with acteristic of the individual. This, along tion might consist of a combination of the biofeedback to give the computer with the test scores and personal health what the user knows to be healthy food a reading. In addition, though, the user data, creates the total personal profile. groups and, within those groups, what the enters a selected activity that she must do individual particularly likes. Certain kinds on a given day, The computer in turn, The user would have to enter information of foods that support certain kinds of using the biofeedback and other data, on her activities. There are two categories activities should be grouped together, gives the complementary relaxation ~I_u~ntur~ of activities to be considered: the work· For example, meats, well-cooked and activity and diet that would support the productive and creative activities, and the spicy foods tend to energize, though in user in carrying out the selected activity, recreational and relaxation activities. a physical rather than mental way. Foods In the active mode, the computer helps Certain of the activit ies might rightly fall in this group support physical labor, the user to determine how she can best in either grouping for some individuals, vigorous sports, and social circumstances support herself in doing an activity that depending upon one's attitude while that require assertiveness. Mental activity she has to do (like conducting a business involved in the activity, Roughly, each is better supported by lighter foods such meeting, studying for an exam or writing grouping would include some of the as fresh fish, fruits, and vegetables, These an article before deadline). following: Work ·productive -Profession groups and others could be detailed, then a activities, office work, writing, the final groupings defined and labeled, The details of the program, and studying, physical labor, computer pro particularly the means of connecting gramming, meeting with business col· CORRELATING THE DATA groups of data, have yet to be worked leagues, composing music, housework, out. No doubt the technology for it doing taxes or bookkeeping. Relaxation The user can have two different kinds of already exists. Even so, it is still possible - L ight reading or writing, playing music, interaction with this program - passive to give an example of how the program playing with kids or pets, making love, and active. In the passive mode, the user would work. playing racquetball, tennis or other sits down at the computer, connects with A New Type of Game favorite sport, doing yoga or taichi, the biofeedback machine, then readings If facial muscle tension is registered, Welcome to an astonishing new experience! ADVENTURE Is jogging, cashing paycheck and counting of the phYsiological response areas are blood pressure is a little high, and there is ORIGINAL ADVENTURE (by Crowther, Woods, Manning and one 01 the most challeng ing and innovative games ayallable lor Roichel) - Somewhere nearby is a callosal cave where olhers have money, and indulging in other pleasures. taken. Based upon what the computer a slight drop in GSR, one can assume that yo ur personal computer. This is not Ihe average computer game in lound fortunes in treasures and gold, but some who have entere :':'...... :.~::., ...... '.'.... '. ':'...... :: .: :.<.... :;:.:...... ': . : '. .... A new mechanism for communicating with a computer has been made possible BY DAVID D. THORNBURG through the recent introduction of the Presto Digitizer ™ tablet. This novel device allows personal computers to If you are like many people who have accept a mode of communication that Most people who have been around large used typewriters, you may have devel many of us use every day-hand printed computer installations, or who have square contains a circuit board which can oped some proficiency with a computer characters. The tablet was developed with attended computer trade shows, are be seen through a 6.5 cm square opening. keyboard and thus not feel impeded in several goals in mind: probably familiar with graphics tablets The circuit board is etched into seven using it for interfacing with a computer. that allow the computer user to draw distinct regions, six of which are con "What!? Have my computer understand Even the most casual hunt-and-peck • The tablet should allow the computer pictures that are displayed on the nected to inputs on the parallel user port my handwriting? I can't understand it typist soon acquires an advantage in this to adapt to each user's printing style. computer screen. These graphics tablets, of the personal computer. Since many low cost in the near future. Because the half the time. You Say I can hand print regard when compared to someone for which can cost SSOO or more, actually manufacturers have a parallel input port tablets presently being shipped are set up characters and they will be recognized? whom the computer keyboard is totally • Most users should be able to learn to measure the precise location of a special for digital joysticks and other add·on to operate with the Commodore PET, 11,at the device, software, and ifistnlC foreign. The problem becomes severe write on the tablet in a short time (30 pen on the tablet surface and send these peripherals, versions of the PrestoDigi this computer will serve as our example rion manUilI only cost $50?" though when the computer is introduced minutes or less). signals, as a pair of coordinates, back to tizerTM designed for use with other in this article. In the PET the parallel into a classroom of children who are as the computer. In contrast to these gen popular computers will be available at 110 port is accessible through an edge Recently, David hils been hearing parts young as eight or nine. Anyone who has • The tablet should be available for a eralized graphics tablets, the Presto cormector on the back of the machine. of the above conversation a lot. His watched children at computer consoles sufficiently low price so that every DigitizerTM tablet is optimized for Each of the six tablet regions is con· company, Inllovision, at P.D.Box 1317, can only marvel at the perseverance with personal computer could be equipped character recognition and thus is set up to ,\ nected to a different bit of this port and look at stroke direction and sequence a special pen which contains an electrical Los Altos, C4 94022, has developed a which these enthusiastic youngsters scan with one if desired. PrenoDigiti2Etr TM data entry "pad" that accepts hand the keyboard looking for the right keys rather than to measure precise pen stylus contact is connected to the ground printed, single characters. It "learns" to to type. If interacting with a computer The resulting tablet design (on which a position. This characteristic allows the cormection on the user port. When the read and recognize your printing style. didn't have other rewards to offset this patent is pending) has met all these goals PrestoDigitizer TM to be sold at one user touches the pen to any of the con problem, many people might give up in and has provided an additional advantage tenth the price of a low cost generalized ductive regions of the tablet surface, the 1 hove used the pad and know that it is frustration. Even highly motivated users when it is used in classrooms. When a graphics tablet, including compact char corresponding input of the parallel port one of those first steps in a long line of must lose some sense of continuity as child is writing an answer to a question, acter "learning" and "recognition" soft is brought from a logical I to O. In this innovative consumer products that we all their attention is diverted from answering rus or her brain is continuing to work on ware. When used with the 8K Commo· 'manner, the user is able to have the will see in the next few years. In fact, a question to the task of finding the right the problem even as the hand is forming dore PET, for example, the base software innovision computer keep track of the region of the there are simple adaptations of this cur keys to push to get their answer into the a character. It is certainly easier to stop (written in BASIC) occupies only 2K tablet in which the pen is located. bytes of RAM. rent device that bubble up ollce you have computer. Clearly, an improved interface in thl middle of a wrong character when nyll.ls tried it-entering patterns of yes/no between people and computers is needed you discover a mistake while printing In contrast to most small computer pe responses, five ''finger'' key functions, that allows the computer to accept in than it is to stop once you have hit a While variations of this tablet are being ripherals on the market today, the func and so forth. You are reading about the formation in a convenient form for wrong key. This feature alone suggests developed for various applications, the ... connector for the computEtr tion of the PrestoDigitizer™ tablet is parallel port future, and it is now. - RZ people to use. that handwritten character input might most common configuration is that completely controlled by software. For shown in Figure I. A frame about 10 em Fig. 1. The Pres100igitiz.r1M T.blet use in character recognition, the program 16 RECREATIONAL COMPUTING JAN·FEB 1980 17 found that the recognition accuracy 1 2 6 INY PASCAL improves if the "learning" process is carried out using carefully defined "An improved interface strokes, with close attention being paid to is needed that allows the the regions in which the pen is moved FOR TRS-80 computer to accept informa during the formation of each character. At last your TRS_80 can run Pascal too! The Chung/Yuen 3 tion in a convenient form for Once proficiency is gained on the tablet "tiny" Pascal Is fully implemented for Level n TRS . 80, people to use." (which takes a small fraction of the time 16 K and uP. You no longer need be left out of the growtng required to understand a typewriter key. group of Pascal users, b8(:ause People's Pascal gives you 4 5 everything you need to write structured Pascal programs: board), many users find that they can _ tiny Pascal compUer _ complete text editor for print characters at their normal printing writing your programs _ complete tiny Pascal mono . speed with error· free recognition of these itor _ sample Pascal programs • user's manual which supports the PrestoDigitizer™ can strokes by the computer. VOL. 1, No •• 11.~ (TRS. 80 Computing issue 1:4) monitor the user port and make note of People's Pascal is both a powerful, structured language the sequence in which the pen moves The tablet design was optintized to allow Fig. 2. Stroke sequence for the letter B and "CPU expedltor". People's Pascal programs execute from region to region. TIlls is illustrated recognition of the entire English alphabet COMPLETE DOCUMENTATION at least four times faster than BasiC, and often eight. Urnes for the letter B in Figure 2. In this figure and numerals, while still allOwi ng the to be able to adapt to our individual re FOR PEOPLE'S PASCAL I & II faster! Special functions open up the complete graphic we have numbered the six regions of the recognition program to use exact string quirements and desires, rather than allow (People's SOftware tapes 3 & 6) capability Of TRS.80. You now have the mea.ns to write those dazzling, impressive, high. speed graphics programs tablet which are monitored by the com matching for character identification. the computer's design to dictate how we puter. To draw the letter B as shown, the Since string comparison in BASIC is that are great for games, plotting, statistics, etc. must interact with the machine. Rather For the serious computerist, side two of People's Pas. user starts by placing the pen in region 1 fast, the time delay between signaling than start out with a predefmed stroke cal n (tape 6) contains a larger compiler and complete and moves it through region 3 to region the end of a character and seeing it dis set that all users must copy, a "learning" PEOPL source to the compiler, written in Pascal! This means you 4. The pen is then picked up and moved played on the screen is almost imper program can be used to accept operator can re_c ompile the compHer, rroking changes, adding fea. to region 1 again. The second stroke takes ceptible. ge nerated stroke sequences which are tures, etc. (but this will take at least 36 K RAM and a solid the pen through regions 1,2,3,5, and 4 then defmed to be representations of knowledge of programming). in sequence. To signal the completion of One of the more valuable features of various letters and numerals. As long With the complete People's Pascal operating system, the letter, the user then touches the pen a tool like this is that it allows adaptive as the user is consistent, the identifica you can save and load botlJ source (Pascal) programs, and compiled programs, to or from cassette tape. This means to region 6 (or lifts the pen from the programs 10 be written. Adaptive pro tion process will work perfectly. Ordi tablet for a short time, depending on how grams allow a device such as the Presto: that once you have de. bugged a prol;ram, you can save the narily , the user would draw stroke se P_code (compiled program) and thereafter, to run the pro. the program was written). The sequence Digitizer™ tablet to be dynamically quences which appear graphically similar [13412354} is then associated with one gram, you need only load the super_fast P_code. molded to the style and needs of indi 10 the desired letter or numeral, but as Here is a partlal Ust of People's Pascal features: B. way of writing the letter vidual users. While devices of this type far as the computer is concerned, the user recursive procedure/functions • for (loop) • case are rare, we should expect the computer can make a B that looks like an 0 and a If/tlJen/else • one_dimenSional arrays • write • read Once the user has signaled the completion ' constant • repeat/until (loop) • "peek & poke" • plot Q that looks like an L. 111e correlation .'" •.* ••• -,...... "'--'-' of this character, the program can com between the strokes which are drawn on ...... - ..... ~.- .~~ •. ~ ... -~. (graphics for TRS. 80) pare this sequence of strokes against a the tablet and the character thai these I>£A.LER INQUERIES INVITED table of previously stored stroke se strokes are chosen to represent is totally quences which are correlated with the up to the person operating the computer. People's Pascal I(tape 3), computer information exchange, inc.- letters of the alphabet and with the If the user later changes his or her print I box 158 san luis rey ca 92068 amt. numerals. If a match is found with one of is written in BasiC, Imp. ing style , a character may not be identi· lemented for TRS _80 by --- enc!. I these stroke sequences, the resulting char· fiable. At this point the letter which is John Alexander of Ber. PEOPLE'S SOfTWARE, includes 509 per tape postage/handUng(v1alst class) acter will be typed on the screen or to correspond to this stroke sequence wick Australia. It com_ I ( ) Tape r Lev n 34 ass'td programs, or ( ) Lev 1, 24, $8; $8.45 1n CA treated in the same manner as if it were (Z, for example) can by typed. If this piles more slowly and is ( ) Tape 2 Level II "Common Basic Programs", $8; $8.45 1n California entered from the keyboard. new stroke sequence is encountered in harder to use, but inC. I ( ) Tape 3 Level n PEOPLE'S PASCAL I, $15_50; $16.40 CA residents the future, the program will then recog ludes instructions for I ( ) Tape 4 Level I, 17 assorted programs, $8, $8.45 CA reSidents (tax) New "'Users can train themselves on the nize it as yet another way for drawing converting to disk. Peo_ ( ) Tape 5 Level D, 28 assorted programs, $8; $8.45 CA residents (tax) PrestoDigitizer™ easily. We have found the letter Z. From the operator's point ple's Pascal n (tape 6) is I ( ) Tape 6 Level n, PEOPLE'S PASCAL II, $23.50; $24.88 CA residents that it is better to start out with programs entirely by the Chung/ Make checks payable COMPUTER INFORMATION EXCHANGE of view , the computer starts out with Yuen team and Is a fur_ which use a limited character set (e.g., the total "ignorance" of his or her printing Charge my VISA ( ). l\lasterCharge ( ) 11' ______numerals and a few other symbols) before ther development stage style. As tinle goes on the computer '!ets of their concept, Full doc _ I ______(signed). expires _____ having the operator teach the computer "smarter," until the computer has fully umentation included. his or her complete repertoire of letters. adapted to the printing style of the i'1di other People's Soft. I TIlls allows the computer user to become vidual operating the tablet. ware tapes $8. familiar with the new writing surface, and name to see how much variation in the stroke As for the keyboard, novice computer sequence will be tolerated by the program users will have plenty of time to acquire which is performing the recognition task. typing skills after gaining expertise with street address Usually by the time the third set of the computer. After all , we each learned strokes has been received by the com to hand print letters on paper before puter, the accuracy of the recognition learning how 10 type. We now have this TRS. 80 trademark program will be nearly perfect. We have option with computers as well. Tandy Corporation City, state, zip 1980 18 RECREATIONAL COMPUTING " Table of Equivalent Codes Now we create another version by moving the other leg and both the arms. Dot Code Shonhlnd Code Texas Instruments (Binary) (HexMllICimll) 0000 • ... , I 001. 2 0011 3 .'00 4 0101 5 0110 6 BY RAMON ZAMORA 0111 7 tOOO 8 1001 9 1010 1011 Once again we visit the adventure/and of the new TI 99/4 1100 Notie. thltlenen ere Home Computer. In the first article, Don Inman showed you 1101 u ... d for theM. how to use the TI to create a single graphics character that 1110 1111 he called Mr. Bojangles. ~l If you rapidly alternate your eyes between the two pictures, you get a sense of how Mr. Bojangles looks when he is "danc· Don asked me to complete the story of Mr. Bojangles for you We will return to use this table in a short while. ing." -to make Mr. Bojang/es dance. So here we gol Let's see if we can "animate" a character on the TI screen. - RZ ANIMATION The TI BASIC program that creates the two characters and animates the dance is given below: MR. BOJANGLES What does it mean to animate a character? On the computer screen, if we print a character, wait a short time, clear the 10 REM U. TI ANIMATION ••• When we left Mr. Bojangles, he was standing still. The program screen, wait again, and then repeat the cycle, the character 20 CALL CLEAR Cleer lhe screen. that generated the character was in a loop that displayed the appears to "flash" or "blink." If each time we print the char· 30 AS- "995A3C3C3C3C4484"} Shorthand codes for two tiny figure on the video. Mr. 80 (if I can be so familiar) acter, we also move its position, then the character appears to 40 BS-"1899FF3C3C3C2221" charllCten. Define the characters IS is about the site of a letter or number, and is quite small. "glide" about the screen. There is an illusion, created by the 50 CALL CHAR 196, AS) \ Code596 and 97. We will enlarge his picture and show you how he looks. "flashing" and "gliding" that lets us animate screen activities. 60 CALLCHARI97,BS) 1 70 CALL COLOR 19,2, 16) Set the color. 80 CALL VCHAR 112, 16,96) Display fiBt cherlCter. We must create the illusion of movement to get Mr. Bojangles 90 FOR DELAY - l TO 100 \ WIlt. to dance. We will do this by establishing two versions of our 100 NEXT DELAY 1 original character. Each version will be slightly different so 110 CALL VCHAR 112, 16,97) Display MCond charlCter. that when we apply the "flashing" technique, Mr. Bojangles 120 FOR DELAY-l TO 100 \ Wait. will appear to dance. 130 NEXT DELAY f 140 GOTO 80 Make hIm dance forever. The original Mr. Bojangles stands rather stiffly. let's have him change his position by moving one of his legs as fo llows: The Shorthand Codes used to create the characters are assig ned to string va ri ables (A$ and B$) in lines 30 and 40. Can you decipher how these codes relate to the patterns of dots shown in the figure? Look back at the Table of Equivalent Codes for a hint. If you are stumped, refer to Part 1 of this article in the last issue of Re. The new characters are defined to be character codes 96 and 97 in lines 50 and 60. The animation of the dance begins with line BO. This animation is quite simple. The next steps would be to You may recall that TI graphics characters are formed by turn have Mr. Bojangles dance across the screen, have him turn ing on the "dots" within an B X B area on the screen. The flips, and perhaps add Ms. Bojangles for some live disco action. dots are turned on (or left off) when we send eight pairs of With the TI 99/4 Home Computer, your imagination is the the Shorthand Codes to the computer. A detailed discussion only limit that exists: of these codes appeared in the last issue of Re. (For even more information, look for the book, Introduction to TI WHAT'S NEXT BASIC· from which this series of articles is taken.) For reference, the table of equivalent dot and shorthand codes The next issue of RC is going to be an issue on Games and is repeated below: Recreations. We will present a unique small game designed for the new TI machine. How about a game that combines sound, • Introduction to Tf BASIC. Inman, Zamora and Albrecht. Hayden color, graphics, and animation? O. K., you got it! See you next Part 2 Book Company. Inc., 50 Essex St., Rochelle Park, NJ 07662, 1980. issue. 20 RECREATIONAL COMPUTING JAil: ·FEB 1980 21 . " . , Capture Listing , - - III Rtll 11_11[, CAPTURL ~2~ 1 If" LfJO'" TltEN 4300 - 42~ ~ PRINT! PRINT "THAT LETTER liAS BEEN CAPTURED,··, 61)11) . 271 - U'S REH A Game for lOur PET • ,II RD' In HAC OOLE5BY 2/2111& 41161 PRINT' PRINT "I DDN 'T UNDERSTAND yOUR 1I0VL ••• •• • & " 115 REII LAST RIVISIC« 6f29f19 Ull PRINT·' TYPt INS rOR INSTRUCTICWS·· . ) Ie RU' 4881 PRINT" TYPE BDA TO PRINT ntE BOARC'· In Rt., A OAME 'PR I OR 2 PLAVlRS • 4291 OOTO 41.1 43111 R'INTILI~HHI&) ' C'Llx)'R' I&1 I ~ . " . 13 ~ REf< COPYP I 3HT 1978 BY MAC OOL1Sl'V , 8 1_0 Ill., PEIIHIS510N ORANTEO TO US!, 43'11 ChPIl 1> . BUT NOT TO ULL. UU r OIl .J'I TO 25 , I~' RU' ~. In Rt., UII !II'R'R<.J)' Ir R.'I OM RI'U ntDl 4'eB - .Q:\I t 1118 REII ... INITlALIEATION U21 , C.'C'C'.J" IF ce'l OR CI'41 nttN 4510 A .,n -A l ell PRINT ··{ CL~I · ·" 'OR .1'1 TO 11, Pili NT "IIIIOH11··,, NUT .I 4431 , U.'UIl$ Some SiJDP.l. Language Games ALearrring and Partial Dictionaries Program for BY HERBERT KOHL Herb and his wIfe Judith are co-directors o[ Coastal Ridge Problem Readers - Research Qnd Educarion Center in Pt. Arena, C4. The center is a non-profit educational organization designed to provide - - both theoretical and practical support to people involved - - in progressive educational activities. - -__ In this ongoing series 0/ articles, Herb challenges you to ~- send in programs that implement these game ideas. Herb, an ERIC SEVCIK AND JIM SEVCIK educator and writer, promises to keep rupplying you with a stream of educational (and /un!!) games for YOIl to program. In the May-June isrue of this year, we published an article. comments like, "Sick kids with your handwriting don't belong - RZ "Peter Om Now Read. " about a dyslexic boy whose reading in school." problem was helped by a word timer program on the TRS-80. The reader response was enonnous. Adjusting to a diabetic situation, a new school, adolescence and an aggressive. defeatist school envirorunent was too much In addition to writing Alice in Wonderland and Through Ihe There are a number of interesting questions that can be asked Eric Sevcik, a 16 year-old dyslexic lad, began with the basic all at once. Two thirds of Eric's sophomore year were lost. His Looldng G1QJJ, Lewis Carroll was a master at creating games about doublets. Can any three leller word be turned into any idea in that article and developed a PET equivalent to the spirit sank, but didn't quite drown. and puzzles. Here is a word puzzle called Doublets which he other one using Carroll's rules for transforming words? What reading program. Our cheers to Eric for a notable crealed in 1879. It is easy to understand the puzzle by con. about four letter words? In order to come up with answers accomplishment! During this time Eric often retreated to his room to find sidering two simple examples that Carroll uses: for these questions partial dictionaries of English are needed, inner strength. It was then that he started to read about one a dictionary of acceptable three leiter words and another The program tape ;s being sold through Computer Pathways electronics and computers. Last year, by some great fortune, • Drive pig to sty of four letter words. These dictionaries would be very useful Unlimited. 2151 Davcor Street SE, Salem, OR 97302. - TV a PET 8K computer was donated to Eric's elementary school • Raise four to five for playing other word games. For example it is possible to by an interested parent. In a visit to his old school, Eric extend Carroll's rules so that words can be replaced by ones BACKGROUND (Jim Sevcik) expressed interest in the PET. The answers to these challenges are: that rhyme with them, so that letters can be inverted so that anagrams can be allowed, and so forth. At one POinl it might Eric Sevcik was diagnosed as dyslexic when he was in kinder In the "Peter Can Now Read" article in RC Eric saw a possible • pig-wig-wag-way·say-sty be possible to develop nontrivial rules so that aU three and garten. Primary grades were a constant frustration for Eric way to help the PET break into the elementary classroom. • fou r .foul-fool-foot ·fort -fore ·fire -five four leiter words are transposable to each other. because of his inability to read or write. With poor fme muscle During the summer, the donor arranged to loan the computer control and dyslexic preception, writing, spelling and reading to Eric for two weeks if he would try to convert the TRS -80 In each case the transformation is made by changing one letter Three leiter words can also be used to develop magic word were almost impossible. These problems caused Eric's teachers program for the PET. (Everyone thought that BASIC-to in each step and making a new word with it until the goal squares-grids where the words read the same across and to discount his superior reasoning skills and knowledge of BASIC conversion would be a relatively Wlcomplicated task.) is reached. The rule is that at each step a word must be made. down. science. Ouring these years, Eric's self image was under steady No nonsense syUables are allowed. Here are a number of attack. Finally, the school had confidence and trust in Eric! The doublets: school was offering him a private computer in exchange for a By sixth grade, Eric's reading progress was improving. Oral simple programming challenge! • Turn eye to lid t e a n t reports were often an acceptable substitute for written work. • Make tea het Seventh grade, or Jurtior High , was a good year for Eric with Eric's family teamed up to give him maximum freedom and • Change elm to oak t a n e w lee ' only handwriting and spelling problems. He had continued to support. From 7 a.m. to 11 p.m. every day, stopping only for • Put rouge on cheek [!Ie t w 0 e e excel in science. biological needs, Eric worked on the program conversion. With ~ no one to tum to for technical help, he relied primarily on the Answers: Diabetes struck hard in April of Eric's gth-grade year. In and PET User ManuaJ and Radio Shack reference books. Eric knew out of school and hospital was the story for him during the that elementary school kids needed this program. • eye -dye-die -did -lid It would be interesting to see if some word squares can be next 9 months. With the strong positive support ofWs teachers • tea -sea -set-sot -hot transposed into others using simple rules of leiter substitu and school, Eric completed all 9th grade work and was The task was completed! As of the end of those two weeks, • elm -ell-all-ail-air -fir -far -oar -oak tion and inversion. Again dictionaries of acceptable words credited. Eric walks straighter, talks clearer and laughs more. This year, • rouge -rough -so ugh -south -sooth -booth -boots -boats· brats could be used either to actually find words to solve these high school is no threat. His handwriting and spelling still need brass -crass -cress -crest -chest -cheat -cheap _cheek problems or to correct solutions. Eric entered High School with positive expectations. Because work, but he has started to type. Most important to Eric-the Eric was "different," the teachers and some staff inadvertent kids in his old elementary school now have access to infmitely © 1979 by Herbert Kohl ly attempted to destroy Eric's self·worth with frequent patient reading help in the PET program. 24 RECREATIONAL COMPUTING JAN·FEB 1980 25 1 INTRODUCTION TO PET READING PROG RAM EXTERNAL TAPE RECORDER (Eric Sevcik) A cassette recorder is needed to load the program into the This program is the PET equivalent of the "Word Time r computer, of course. Two options are possible: Progra m Options Program"listed in the article " Peter Can Now Read." The PET Reading Program does everything the original program does, A. Purchase the Pet accessory and follow directions for DO YOU WISH TO START AT THE BEG INNING OF and it uses special PET graphic characters. Additionally, hookup. then modify the POKE commands as necessary. THE WORDS? YES will rapidly present the next section's words. several different options have been built into the PET program B. Purchase an inexpensive portable recorder and connect it YES will start the word list at the first word. Woming: NO will let you go to the next option. the voice tape will not be synchronized unless you stop 00 YOU WANT TO MAKE A TAPE FOR THE that are not in the original TRS·80 program. through a switching interface. (Option B is about II.! the price of Option A.) the program and start from the beginning. COMPUTER? NO will let you go to the next option. YES refer to the instructions titled "Recording a New I wrote this program because I had never before been given an DO YOU WANT TO GO TO THE NEXT SECTION? Voice Tape of Words." opportunity to write a program for someone else , and it was The interface allows the PET to control the power supply to YES will advance the program and voice tape to the next NO will let you go to the next option. the first time I had been given a problem to solve on a the tape recorder. Construction and testing is best done on the )Cction of words. 00 YOU WANT TO VERIFY TAPE WORD SYNC? computer. P·board . Once tested, you can shorten the leads, retest, then NO will let you go to the next option. YES will display each word and play the voice tape. thus liberally apply epoxy glue. The assemblage is now a solid uni t 00 YOU WANT TO CHANGE PACE? allowing you to check the synchronization. Woming: a CH ANGING THE WORD LIST AND SCAN RATE that will take rough handling. YES will brin& you back to the ? PACE CHANGE? sync check requires that none of the other options have request. been executed and that you att starting at the very The list of words that the program uses is contained in the Parts lilt NO will let you go to the next option. beginning. data statements 3000·3440. The words are organized into DO YOU WANT TO LOOK THROUGH THE SECTION NO will cause the PET to display BYE and end the sections of ten words each, though the section length can be Experi menter Socket (ImaU P-block) OF WORDS? program. changed fo r convenience. 10k OHM ReDstar Y.i watt 470k OHM Resistor Y.i watt The words for each seC[ion are in the first line of the paired 2N2222 NPN 500 MA HFE: lOO-300TransiJtor data statements. This line contains the Group Number, then IN914 Switching Diode SVDS DPDT DIP Relay the Section Number followed by the words separated by commas. The second line of the paired data statement contains Instructions to Ru n Program the code for controlling the individual scan rate (speed of letter highlights) for each word. +4.5V Loading the program The section and group number identity of the next set of Tuman PET words to be presented wiu be displayed. with To replace words, just recode the first data statement the Insert the PET Reading Program tape, program side up The PET will ask you if you wish to go on with the new replacement words. Be sure thai the second statement has and rewind. indicated set of words . the same number of scan rate codes as the words in the rust lN914 • Type LOAD READING and hit RETURN key. A YES response will cause tile program to display the statement. In changing the scan rate, remember that the larger C Press PLAY control when PET tells you to do so. words. the number the slower the speed. 1 suggest that you change 1 Shortly the PET will display FOUND READING, then A NO response will aUow you to select from the available c one pair of data statements and test them successfully, before to Tape: R ecora.r LOADING. options. embarking on a wholesale change. Finally the PET will display READY. (See Program Options. shown above.) Pin C The screen will clear then display the section. group and Running the Program word numben, before presenting the word letter by If using voice reinforcement, insert word tape into the letter. Pi nN c external tape recorder. The letter highlight sequence will start after all the letteu Type RUN and hit the RETURN key. of the word are displayed. The program will tist a series of instructions to the The pupil is now to try to read then pronounce the word teacher. Hit the D key when each is donc. (If not using displayed. voice reinforcement, ignore the instructions and hit D for Hitting the minus (-) key will cause the program to pause the first 3 instructions anyway.) the highlights so that the teacher can work with the pupil if desired. PET Instructions After the pupil has decoded and pronounced the word hit the asterisk (.) key to stop the highlights and to activate MAKE SURE THE INTERFACE IS HOOKED TO THE the word (voice reinforcement) tape. (If not usin8 voice CO MPtTTE R. This is to insure that you check the inter reinforcement hit the· anyway.) face connections. The PET will then display DID YOU READ THE WORD REWI ND THE TAPE AL L THE WAY. Verify that the RIG HT? PLEASE TYPE I FOR YES OR 0 FOR NO. Recording I New Voice Tape of Words word tape is inserted correct side up and is rewound all Follow the directions. the way in the external tape recorder. Be sure the external tape recorder is attached as if you The next word of the Section will appear after either a I PRESS PLAY ON TAPE. Press PLAY control on the Materials Needed to Run Program were going to run the program. or 0 is hit. • PET Computer Insert a blank tape into the external tape recorder and external tape recorder. A rocker launch display will show the correct number as • Pupil (someone to interact with the program) rewind fully. The PET will display I AM NOW MOV ING TO THE each section is ended. • Teacher (someone to set up and start the program) RUN the Reading Program except when you are asked to BEGINNING OF THE RECORDING. At this time the At this time, the average time used per word will be • PET Reading Program tape press PLAY, press both the PL AY and RECORD controll. word tape is being positioned by the program. Do Not displayed in the upper right corner. • PET Readins Program Word tape (for voice reinforcement) Answer NO to questions and the options to make a new Touch Anything!! The program will recycle from the ? PACE CHANGE? • External tape recorder connected to PET as pre$CTibed ..... The PET will display ? PACE CHANGE? Follow the request until the word list is exhausted or until you Note: The last t".'O itemJ on not needed if the foice ninforce Plug the microphone into the external recorder. instructions to speed up or slow down the word presenta indicate that you do not want to go on by typing in NO ment featun is not being used. Hit D and follow the instructions displayed on the PET. tions.. to the continue requt$t. 26 RECREATIONAL COMPUTING 27 ., _ f'OI«JIIIIC£ ..... U From tr~ Makers of THE Basic Switch'" for Old PET®Owners comes ~ 0'0([....::1[-...... _ POr.oAC[ -I~.' 1 ~~ '7'1 IACI;"IACI;' " Listing -~ 'l'I5-~. r.osu~ .... I'~ _ !09!1 PRI"'";'- OO'OI"~ The Spacemaker'" ,_ PIWI'":l C!H'IIIU tHECK lt~1 .. 001011'8 '!Ie;! (;(1110 'f .... ·P·'H[>#.t:...... 1I18l OOTOH)1I2 -. ' 1 ,1 PRIHT"HlT , D, lOKI, DQ£- for New PET Owners 1828 PltlIlT- _ Iilft 'lfTERI'IW;E IS tt:lO>.U 10 TOE --(C"'UIP' Co05IJI,M3 I~ POI ~~-~ RE51DR£ RDI .utIFV •2542 ""IH' "_ · ~ PRINI· ~ · Gol\IJII68(I Pltllll'_ " _ 2501. PRI ..,· 11111_1' oostJNIMI PIt,K,· ...... III EIARI · flO$Ua. •• = I£KlI. M Spacemaker ard ROMdrlver will 2$'9 PIIlllf":v 28 RECRE ATIONAL COMPUTING JA N ·FEB 1980 29 Continued from pg. 41 mao in his work, a machine which can be totally controlled by each and everyone of us. That understanding is what we are 6502 User Notes, trying to achieve. The PO®Gazette The issue of computer awareness is the topic of a one-day workshop conducted by the authors. Typical workshop and PO User Notes User Inspi red Hardware Products attendees include educators, owners of small businesses, librarians, social workers, and medical professionals. are now a part of Unlike traditional computer workshops that stress hands-on encounters with computers, our workshop deals with under COMPUTE. "- lying issues in computer demystification. First we have each The Journal for Progressive Computing New Directions in participant complete the sentence "A computer;s . .. ". Next Continuing major sections on Business, Indus members of the group express their opinions on computers - trial and Educational Applications and Re good or bad. During the process of sharing views with the rest sources, Plus The PET\!) Gazette, The ATARf\!l Numerical Computing of the group, each member Hnds that there is a lot of conunon ground in various people's experiences. The rest of the Gazette, The APPLE~ Gazette and The SBC morning is devoted to understanding what a computer does, (Single Board Computer) Gazette. All in each where computer jargon originated, and how to cope with com issuel puter myths (e.g., how to handle someone who tells you that A Sampling of Our 104 page "Super" Fall "the computer made a mistake"). By lunchtime, the major IlIue : demystification process has been completed. The afternoon Tokens in Microsoft BASIC: Harvey What happens IJS more micros get into the BY HARRY L. PRUETZ is then devoted to a description of different types of computer Herman. ATARI Computers: The Ultimate hands of the people? We can expect new services (time-sharing, remote batch, personal computers, etc.) uses for computers, new styles of soft General purpose computers were initially Hopefully, personal computer users now and a description of case histories which are relevant to the Teaching Machines?: John Victor. Carl ware design, Qnd as Harry suggesrs~new designed for numerical computing. They writing programs requiring involved audience. Moser Presents a Universal 6502 Memory IuJniware based on the personal com· used a fairly large word size and a narrow numerical calculations will discover alter Test. Microcomputers in Nuclear Instru puterist's needs. Take a peek into the definition of integer and floating point native software methods that can be In our next article we will delve into some computer myths in mentation: Joe Byrd. AIM 65 Review: Don future with us . .. Qnd tell us what you number representations. The standard implemented using hardware. Perhaps more detail. Until then you might want to catalog your Clem. Mastering The Ohio Scientific Chal see! - RZ 8-bit byte used in today's microproces they will find methods that provide feelings about computers and share this article with some lenger lP. A Learn-By-Dolng Approach: sors allows for more possible number better accuracy at about the same price friends whose views of these machines might differ from Now that microprocessors have been in Keith Russell and Dave Shultz. CORVUS representations, using software utility as the old standard implementations. yours. use for several years, heavily numerical routines. Even "impractical" number Proving that a method works in all cases llA Disk Drive for APPLE: A Review by software packages are becoming more representations proposed in the past and determining how to implement the Michael Tulloch. Pierre Barrette on Micro common. The history of maxicompulcrs are perhaps practical today using micro method with hardware can be left to the computers in Education. Len Lindsay Re and minicomputers predicts that special. processors. The most obvious reason for professionals. views Three Word Processors. PET in Trans ized microprocessor hardware for this is that higher level languages (BASIC, ition/ROM Upgrade Map: Jim Butterfield. numerical applications should start APL, PASCAL, FORTRAN,and COBOL) o@c r II S ln~ S ~d C C Trace for the PET: Brett Butler. 32K PET Pro appearing soon. However, the specific are mostly interpreted languages on grams Arrive: Len Lindsay. Using Direct design of the hardware might involve microprocessors and are slow when Access Files With the Commodore 2040 completely new concepts because of the compared wilh machine coded programs. Dual Disk Drive: Chuck Stuart, plus Re sheer number and diversity of personal This fact makes the eXIra time spent in views, Resources and Products. computer users. more involved numerical utility routines o ~dlld O C New Features Coming In January Include: relatively small when compared with total Personal computer users Gust three computation time. "Rambling" by Roy O'Brien, "The Tape decades after the start of the computer 114, 112, Full Page Exchange" by Gene Beals, and the Single revolution) are about in the same situa Another reason is that the amount of Board 6502 by Eric Reinke. tion as amateur astronomers relative 10 time spent on numerical software rou 1960 BmontNy Subscription (Six Issues) $ 9.00 the centuries-old field of astronomy. tines is already high even for the standard Inside ~SUper'. Fallssue With 1980 Subscrlptlon 100 Personal computer users do not have the integer and floating point representations $10.00 specialized knowledge that many profes as used in the past. The longer computa Front & Back Make Check ~ Money Order Payable to COMPUTE. sional people have. But, perwnal com tion time needed for "impractical" Post OffIce Box SH9 Greensboro. Nq1h Corollna 27403 USA puterislS are numerous enough to make representations would not be excessive. Covers imponant discoveries related to com COMPUTE" the new puters, and knowledgeable enough to provide constructive criticism about com 6502 resource magazine for puter hardware design. PLEASE SEND FOR Advertising Manager PET. Apple, Atari, Kim, Sym, Aim RATE CARD People's Computer Company 1263 E1 Camino ReaJ , Box E and OSI Owners. (41 5)323.311 1 Menlo Parle, CA 94025 COMPUTE . The ..IoIJnallor Progressive Computing Is pub !shed by Smal System SeMces.loc. of Greensboro. North Corollna. Robert lock. Editor IPubisher JAN-FEB 1980 31 30 RECREATIONAL COMPUTING General W;~'.o,,",I. ,Jth,o"" 0'" ",.,;0,.. 11'" he resistance troops joyfuUy invert in many ways, is p05$CS$ed of a SUBSCRIPTION ORDER Jelves to gain adminance inlo the tolerance than most, and eontinues to can· Please send me a one-year subscription to Recreational )usly impeded city, Linea and the duct the full power of the rebel Iltack. Yel, Computing magazine (published bi -monthly) for $10. , tal rush once again to where the without paralic] support from Linea and her (You save $2 off the cover price.) ter has landed. resistance decades, the attack is bound to NAME ______enter a failure mode! ant, P-Man! A muter ADDRESS ______Linea had diverted her march across the ~! data fields to bring F·Man to the Mcinlel CITY/STATE ______ZIP ___ suonghold , knowing thaI his powers, once evaulation no.:w:"d~:.~~ "'''''.... <;;.;''-'''' restored, would be of invaluable aid in ;• Billy, you remainder here overcoming the Glitchmaster's troops and , o Check enclosed o Bill me (U.s. only) > with Linea and assist the Angus freeing Microproccuoriand from his noisy ., , Genera.! with dividing our last episode, as '~"';::~;~::';~ o Renewal (please attach mailing label.) ... Underground Resistance Mclnlel, the operator of reign. But now the battle is on, and Castle ~ the G lilchmaster's forces in far off Capital the emulator, had sel • data switch inad,-cr Mclntel is far from the battlefield ... city-andwith the I'm {~~~. ~h:~::::~) Signature _:-::__ -::- __-::- ___=.,--,--: ______~ City. Fortran Man is led into the low-level lentIy backwards, and Billy Basic now a i, myaeIn laboratories of Castle MclnteL Here, with occupies F-Man's body, and vice-versa! Can they make their connection in time International Rates: Canada First Cf8U 0 $17 One Year the help of an in-circuit emulator, his mis to save the Land of the Little People from Rest of WoridAirm.iI 0$23 One Year < Most confusingl But fortunately, a slight w• sing memories (10$1 when he was inad World Surface Mail - I will risk the :engthy and unreliable delivery of re-connection and a brief ZAP of the yertently exposed to UV light while in surface mail hignedl'_____ --;o;-::-:-::--::- ______PROM) are II last restored, with his friend emulator succeeds in switching them back and companion Billy Basic serving as source in to their proper program spaces, and none 0$14 One Year Payment must be in SUS drllWII on 8 US Bank. me! too soon, for realtime is running out! In the memory space of General Wire Quickly they propagate towards the nearby And attack they do, connecting with the wound, outside the walls of Capital City, data field where the great dragon has come other underground supply lines in their and unsupported by any other code, Risides a ml\ior question-will his support down to unload its data cargo, to be met by charge against the capaotive guards which lIero branches without ittsitalion up software arrive in time? But then, alerted by Linea he rself and her entire army! hold up the potential on the oty walls. the staircase generator and into the halls of a sudden output from one of the outpost They advance ever closer through a deadly AD right Comrade, if any the Tower itself. -r....r. elements, all perform an immediate lookup hail of high-voltage noise spikes ... one can handle the Glitch Greetings, Comrade! Your v -... ~ function just as a gigantic, shadowy form connection is none 100 muter'. rile, you can! But feeds o~r them .. lOOn, for we are already look out - the Glitch fam- overloaded! Sirange •.• the place Jeeml deaerted! The guards mUlt hive run om Swiftly F-Man propagates through oly towards its center-the great, dark, ominous Slluclure from which the Glitch master rules his empire, radiating his over. powering noise to all the parts in the Iand Tesla Tower! Without PAUSE he opens the portal with great force, flinging open the massively shielded doors as he CALLs 10 hi!; opponenl I don't know, but P·Man and Billy Basic an riding it! I wonder whll they have in mind ... 4 NO POSTAGE NECESSARY DOmfS But they soon fmd out. so do the troops Within milliseconds the file· protect keys DR. ~RNIILc( IF MAILED As the resistance troops joyfully invert 111111 in the city below, as su ddenly the city is of the city are all destroyed. and the great themselves to gain admittance into the COMPUTER INTHE bombarded with thousands of ... random data structures begin to crumble and fall! previou!.ly impeded city. Linea and the 0 ...... &0"..... ," UNITED STATES passwords! As it goes, the holdup potential of the General rush once again to where the capacitive guard is severely reduced, and as Monster has landed. the Resistance units continue thcir current charge, the Guards are It last over-charged . and break down! BUSINESS RE PLY MAIL tv.uhtion no.~w:,d~:.:~~ FIRST CLASS PERMIT NO. 756 MENLO PARK, CA Billy. you remlinder here with Linea and wist the General with dividing our last episode, as the m,,'·'; 1>001,"0 POSTAGE WilL BE PAID BY ADDRESSEE city-and I'm . hi! Underground Resistance Movement ~;th the GI";h~"; " ~ the GUtchmaster's fortes in far off Ca myself! City, Fortran Man is led into the low laboratories of Castle Mc lntel. Here, DR . DOBB'S JOURNAL the he lp of an in-circuit emulator, his P.O. BOX E sing memories (lost when he was vcrtently exposed 10 UV light whil 1263 EL CAMINO REAL PROM) are at last restored, with his fl MENLO PARK, CA 94025 and companion Billy Basic serving as 51: file! In the memory space of General 1 And with that he turns swiftly and branches Alone and unsupported by any other code, wound, outside the walls of Capital' rapidly away. Our Hero branches without hesitation up resides a major question - will his sUl'-r __ _ _ .. - _. --- • - _ .• I hold up- the potential on the city walls. the staircase generator and into the halls of soflware arrive in time? But then, alerted by Linea herself and her entire army. They advance ever closer through a deadly AU right Comrade, if any a sudden OUlput from one of the outpost the Tower itself. -r.J"". hail of high-voltage noise spilces. one can handle the Glitch elements, aU perform an immediate lookup Greetings, Comtlde! Your muter's me, you can! But "" -... ~ function just as a gi&antic, shadowy form connection is none tOO look out-the Glitch fam lOOn, for we are already feeds over them . Ily hlll • notoriouJ reputa· overloaded! tion ror being sneaky! Strange ... the place IOOmf deserted! The guards roUIt hive run om Swiftly F -Man propagates through city towards its ce nler-the great, dark, ominous structure from which the Glitch. muter ru les his empire, radiating his over· powering noise to all the parts in the land Teda Tower! Without PAUSE he opens the portal with greal foroe, flinging open the massively shielded doors as he CALLs to his opponent What the ••. ? Why, come F-Man! I'ye peeting you! I don't know, but P-Man and Billy Basic are riding it! I wonder what they have in mind ... There are shorter ways of writing the program in "standard" and (if there is room) a remark containing the replaced sta te Put Nested IF Statements in Your Program BASIC; the tests in lines ISO, 160 and 170 for instance, are ment would be inserted immediately thereafter. The following somewhat redundant. We couJd alternatively have sometrung lines wouJd be appended to the program (where 210 is the like: number of the line found to follow 200). listing # 3: 'ABS" and ''SGN'' Application 30000 IF N$-"JONES" THEN 30002 30001 GOTO 210 100 PRDlT "SOLVING A*X*X + B*X + C - 0 !" 30002 PRINT "FOUND! AGE - "jA An Extended BASIC "IF" 110 PRINT "PLEASE ENTER A. B, C;" 30003 GDTO 210 120 INPUT A, B. C 130 LET D - B*B - 4*A*C If the sequel to an extended "IF" clause is itself another Facility 135 PRINT "SOLUTION (S): " , extended " IF" clause, then it also is progressively decom 140 IF A'(l+SGN(D»-O THEN 150 posed. Thls can be seen in Listing # 4, whlch is the output of 142 PRINT (- B+sQR(D»/2/A, (- B- SQR(D»/2/A the pre·processor program acting on our first example. ISO IF A'O'O- SGN(D»-O THEN 160 BY GRAHAM K. JENKINS 152 PRmT "COMPLEX!" Listing # 4: Pre· processor Output 160 IF (I-ABS(SGN(A»)'B-o THEN 170 100 PRINT "SOLVING A*X*X + B*X + C .. 0 !" Mr. Jel/kins' interests include "microprocessor cross 162 PRINT -<;/B 110 PRINT "PLEASE ENTER A, B, C;" assemblers, cross-compilers, simulators, optical character 170 IF ABS(A)+ABS(B»O THEN 180 120 INPUT A, B, C recognition, squash, body-surfing, and, of course, recreational 172 PRINT "INDETERMINATE!" 130 LET D - B*B - 4*A*C computing. " 180 END 135 PRINT "SOLUTION(S):", With the pre-processor thllt Graham presents here. you can 140 GO TO 30000 [annulate programs in a "block-structured" BASIC. and let In passing, it is worth remarking upon the general utility of the absolute value and sign functions for the testing of 141 REM IF A<>O IF D>-O PRDlT the computer unravel the nested "IF" statements. multiple conditions, as shown in the example above. (-B-SQR (D» 12/A, (-B+SQR (D» 12/A If you get by Clayton, Australia, stop and say hello to 150 GO TO 30006 Graham. He WQrks for Telecom Australia Research Labor THE PRE·PROCESSOR PROGRAM 151 REM IF A<>O IF 0<0 PRINT "COMPLEX!" atories. Hit him up for a game of squash, but beware! If his 160 GO TO 30012 This article describes a program (itself written in "standard" playing is as good as his programming, don 'f wager on the 161 REM IF A-o IF B<>O PRDlT ~/B mIltch... - RZ BASIC) which will convert a program such as that shown in 170 GO TO 30018 our first example into a form palatable to a "standard" BASIC compiler/interpreter. Ideally, such a pre-processor would 171 REM IF A-o IF B-o PRINT "INDETERMrnATE!" THE WR ETCHED "GO TO" In fact, some versions of BASIC allow tttis sort of construction yie ld an output like that shown in our second example. (The 180 SlUP (where the repeated "IF" clause means that the consequence program wouJd be even better if it contained an optimiser to 30000 IF A<>O THEN 30002 Ouring the past two years, the humble GO TO statement shouJd be executed if and only if both conditions are true). 30001 GO TO 150 appears to have acquired a distinct odor. Proponents of the But many of us are stuck with having to write somethlng like: automatically eliminate some of the redundant tests.) There 30002 IF 0> .. 0 THEN 30004 block·strUCtlifed languages have developed such an aversion to are two problems in producing such an output. First, the operator in each comparison must be detected and comple 30003 GO TO 150 it that we rmd it deleted entirely from some compilers! Un listing # 2; "Standard" BASIC fortunately (or otherwise, depending upon one's point of mented. And second, some re-numbering of program lines 30004 PRINT (-B-SQR(D»/2/A. (-B+SQR(D»/2/A view), the owners of BASIC systems are stuck with it ... or (with adjustment in associated "GO TO", "IF", "GOSUB" 30005 GO TO 150 are they? 100 PRINT IISOLVING A*X*X + B*X + C - 0 !" and "ON" statements throughout the program) may be 30006 IF A<>O THEN 30008 110 PRDlT "PLEASE ENTER A, B, C;" necessary. Neither of these is insurmountable, but they do 30007 GO TO 160 complicate the issue. Consider for a moment the solution of a simple quadratic 120 INPUT A, B, C 30008 IF 0<0 THEN 30010 equation for its real roots (if any). It would be convenient if 130 LET D - B*B - 4*A*C Alternatively, we couJd require an output like that shown in 30009 GO TO 160 we could write such a program like tttis: 135 PR DlT "SOLUTION (S ) : " , our third example. Unfortunately, "IF" statements which 30010 PRINT "COMPLEX!" listing # 1: Use of Extended "I F" 140 IF A-o THEN 150 compare strings do nol easily lend themselves to automatic 30011 GO TO 160 141 IF 0<0 THEN 150 decomposition using the .. ABS" and "SGN" functions. 30012 IF A-o THEN 30014 100 PRINT IISOLVING A*X*X + B*X + C - 0 !" 142 PRINT (-B+SQR(D»/2/A,(-B-SQR(D»/2/A 30013 GO TO 170 110 PRINT "PLEASE ENTER A ~ B. C;" 150 IF A-o THEN 160 For simplicity, and for generality of application, our pre 30014 IF B<>O THEN 30016 120 INPUT A. B. C 151 IF D>-O THEN 160 processor program replaces each extended "IF" statement 30015 GO TO 170 130 LET D - B*B - 4*A*C 152 PRINl' "CCliPLEX!" with a "GO TO" statement whose destination lies beyond 30016 PRINT -<;/B 135 PRINT "SOLUTION(S):", 160 IF A<>O THEN 170 the end of the Original program. Additional lines inserted at 30017 GO TO 170 the program end then expand the statement appropriately. 140 IF A<>O IF D>-=O PRINT (-B-SQR (D) ) /2 lA, 161 IF B-o THEN 170 30018 IF A~ THEN 30020 Thus the single program line: (-B+SQR (D» 12/A 162 PRINT -<;1_ 30019 GO TO 180 150 IF A<>O IF 0<0 PRINT "COMPLEX! " 170 IF A<>O THEN 180 200 IF N$ '" "JONES" PRINT "FOUND! AGE'" ";A 30020 IF B-o THEN 30022 160 IF A-o IF B<>O PRINT -<; IB 171 IF 8<>0 THEN 180 30021 GO TO 180 170 IF A-o IF B-o PRINT "INDETERMINATE! " 172 PR INT "INDETERMINATE!" might become 30022 PRINT "INDETERMINATE!" 180 END 180 END 30023 GO TO 180 200 GOTO 30000 30024 END 34 RECREATIONAL COMPUTING JAN -FEB .980 35 Listing # 5: The Pre-Processor Program 248 REM THE CURRENT LINE BUFFER CQMKENCes iN "IF" - STATEMENTS PROCESSED required. Rererence to the example shown earlier should 250 COSUB 400 clariry the malter. The tenninaJ "GO TO" statement is 100 R~ EXTENDE D "IF" STATEHENT FACILITY IN 8ASIC. 252 IF S$ <> "IF" THEN 310 The types or extended "IP' statement which can be accom omitted ir the preceding statement sequel was a "STOP" or a 102 R~ IMPLEMENTED 8Y G JENKINS OURING JULy 1979 . 254 REM modated are shown at the beginning or Listing # 5. nus range "RETURN" (since it would then be redundant). 104 REM 256 REM AN "IF" STATEMENT HAS BEEN FOUND ~ can be reduced or extended according to requirement merely 106 R~ THIS PROGRAH READS 8ASIC PROGRAMS CONTAINING 258 RD! DETERMINE WllETHER OR R)T IT IS AN 108 R~ Ul"ENDED "IF" STATEMENTS IN TIlE POLLOWING by adjusting the list or key words appearing in the subsequent 260 RI'21. EXTENDED ONE BY SEEKING THE NEXT KEY WORD _ The astute reader may observe that no syntax checking has 110R~ FClUfS - 262 S 1 - S3 + 1 "DATA" statements, and effecting a corresponding adjust been perrormed upon extended "IF" lines. The reason for this 112 R!l1: If If 264 GOSUB 700 ment to the loop termination value in line 736. The number or is that the pre ·processor only breaks up such lines using the 114 REM IP 011 266 IF S$ "" THEN 370 "IF' conditions which can appear within an extended "IF" designated key words as delimiters. Any syntax errors will be 116 REM IP LET 268 REM 118 REM IP statement is limited only by the user's maximum allowable detected at execution time by the compiler/ interpreter. This HAT 270 REM THE CURRENT LIN! IS AN !lCl'!NOEO "IF" 120 REM IP READ line width. approach leads to a considerable simplification. 272 RD! STATEMENT: REPLACE IT WITH A "CO TO" 122 REM If STOP 274 REM AND (IF ROOM) INCum! ITS CONTENTS 124 REH IP INI'IlT 276 REM THEREAFTER AS A REMARK: INDENT THESE INITIALIZATION SAVING SPACE 126 REM If GOSUB 278 RI'21. NEW STATEMENTS TO SAM! LEVEL AS THE US REH IP PRINT 280 RI'21. ORIGINAL STATEHENT . During the initialization phase, the invariant data is set uP. and The memory requirement or the pre-processor program itselr 130 REM IP RETURN 282 TS .. ''GO TO " 132 REM the input and out put mes are attached. This segment or the can be reduced by omission or remarks, and or lines in cluded 284 GOSUB 500 134 REM AN E~IVALENT PROGRAM, CONTAINING ONLY 286 PRINT 12 , NO); T$; N(3) program may require modification according to the target solely ror speed enhancement (e.g. lines 740 through 746). 136 REH STANDARD BASIC STATEMENTS IS PRODUCED. 288 IF NO)+1 _ N(2) THEN 296 machine. In our implementation (ror an H6000) the Further reductions can be erfected by explicit dimensioning or 138 REM THE EXIENDED "IF" STATEHENT HAY ITSELF 290 T$ .. "RD! " "CHA NGE'- statement is employed to transJate an ASCII deci the L$ and N arrays, or replacing their elements everywhere 140 REM CONTAIN OTHER ExtENDED "IP" STATEMENTS 292 GOSU! 500 mal value ro r the quotation character into an equivalent string, with equivalent discrete variables. The computation or inter· 142 REM AS SHOWN IN TIlE FOLLOWING EXAMPLE - 294 PRINT #2, N(l)+I: TS: L$(l) 144 REM IP 1.>8 IF C>D PRINT "A - ":A and the "DELIMIT" statement alters the nomlal input delim· mediate variables (necessitated by string·handling limitations 296 REM 146 Reo! 298 RI'21. WRITE 1ST 2 LINES OF DECCtlPOSED iter character to a carriage return. The "SCRATCH" statement or the available compiler) can also be averted in a number or 148 REM SET UP DATA. Q$ CONTAINS ~OTATION HARK. )00 REM STATEME'NT prepares a me ror output, and the "MARGI N" statement sets places throughout the program. 150N(0) 1 302S4-1 the column after which line wrap-around will occur during 152 NO) - 34 )04 T$ .. SST( L$(l),S4,SO-S4 ) output. The size or the output program can be reduced by elimination 154 CHANGE N TO Q$ 306 PRINT #2, N(3): T$j "THEN "; N(3}+2 156 DATA "IF" , "ON", " LET", "HAT", "lU!AD", " STOP" of aU remarks and spaces (except those within quotation 30S PRINT 12, N(3}+li "GO TO": N(2) 158 DATA "INPUT", "GOSUB", "PRINT", " RETURN" 310 N(3) - N(3) + 2 It is worth noting that all our output (whether a normal pro marks). This compression will compromise readability, but the 160 REM 3t2 REM gram line , or an extra to be appended at the program end) is user will (or course!) have relained the original source ror 162 REM SOLICIT fILE--NAKES, INITIALLISE PILES 316 Rflt IF STATEMENT SE~EL IS ALSO AN directed to the same me, since sorting by line number can be reading/ modification purposes. 164 PRINT "EXTENDED ": Q$ : "IP":Q$: 318 RI'21. ItXTENDED "IF", LOOP TO DO IT AGAIN brought about at execution time by an appropriate (pseudo 166 PRINT " STATEMENT PRE-PROCESSOR:" 320 IF S$ <> "IF" THEN 336 input) system directive. In those systems where this cannot MAKING IT FASTER 168 PILES *:* 322 S4 - SO 170 PRINT "INPUT PILE IS"; easily be errected, appended output lines should be directed )24S1-S3+1 172 INPUT L$(I) 326 :;OSUB 700 to a separate me whose entire content can then be read back Execution speed should be satisfactory on most dedicated 114 PILE II, L$(1) 328 IF S$ <> " " tHEN 304 and included al the end of the output me immediately prior to systems. Users who pay for processor seconds may, however, 176 PRINT "OUTPUT PILE IS" : 3)0 SO - S4 pre-procesSor termination. wish to enhance the speed. Some available avenues include the 178 INPUT L$(2) 332 RD! elimination or indexed va riables (as discussed above), and or 180 DELIMIT II,(CR) 334 REM orHERWISE WRITE SE~EL AS IS, 182 PILE 12, L$(2) LINE INPUT redundant computations by the judicious introduction or 336 J - LEN(L$(l» - SO + I 184 SCRATCH 12 338 T$ - SST( L$(I),SO,J ) intermediate variables. 186 MARGIN 12, 160 340 PRINT #2. N(3): T$ Une input is errected (through the subroutine starting at line 188 REM 342 N(3) - N(3) + 1 400) using a two-line burrer, so that the number of the next The most critical area ror speed enhancement is probably the 190 REM ADDITIONAL STATEMENTS ARE INSERTED AS 344 RE'2 "EN" THEN 244 386 Rflt tents up to the first key word are extracted and reconstituted ductivity. A number or the modifications discussed can 234 T $ - " StoP" 388 RE'2 "9" TIlEN 422 PEOPLE'S COMPUTER COMPANY PUBLICATIONS • 420 NEXT J 422 US· SST(L$(2),l,J-I) RtlCfelltional Computiflg 0,. Oobb's Joumal 6060 424 N(2) .. VAL( U$ ) 426 IF TS <> " " TIlEN 430 Computer Music Joumlll · 428J·J+l •0" .-8" 430 LS(2) • SST( L$(2),J,LEN(L$(2»-J+l Clubs, userl groups, schools and IIny olherl interelted may 432 RETURN take advantage of discounts for qUllntity ordars of each of oor 434 REM ••••••••••••••••••••••••••••••••••••••••••• ml;l98zines . See temu Oelow. 436 REo! All orders will Oe shipped via UPS-fastlr than the POSt officel • ·: 500 REM ••• INDEtn'ATI0N SUBROUTINE ...... l · 502 REM Dl'DEHTS COHTEtn'S OF T$ (BY PRE PENDING DISCOUNT SCHEOULE ! 504 REM SPACES) TO SAME LEVEL AS L$(I). Ion. v.. d 506 FOR J • 1 TO LEN(L$(l» aUANTITY DISCOUNT RC OOJ CMJ ~ . ~ -- 0:"- ::;:~ U$ • SST( L$(l ),J,I ) !! . .... 0 .. .. .-. 5" Regullr Subscrip· ... " .. .. -'0'.. ~::e~::;:;,e 510 IF U$ <> " " TIlEN 516 ...... -..... tion Aate I Copy none $10 $1S $20 ...... :;;:;;~~~~~ :;:::=:;'C:::c....•••- '-,-- :>:>00"' ...... > Here is a rYe-Tae-Toe game that is a little 610 REM SPACES ARE IGNORED. 5EARCH FAILURE RETURNS emong titles. different from most. Instead of using a 612 REM SO • " " AND 53 INDETERMINATE. AU copies mU$1 be shipped to same name lind llreet IIddreh ; , ; semch algorithm, the program's logic is 614 REM , , , 616 SS • '''' (no p.O. box!. based on a formula. The only problems, 618 FOR 53 • S1 TO LEN( L$(l) ) Pllyment must accompllny order-check Of money order only. according to the author, are tlwt the I/O ...... ~...... ~ .... - o _0 620 T$ .. SST( L$(I),S3,l ) Minimum onl·year subscription. ~ :~ :;!~ : ::! ~:; ~ ~~ ~~5:!~ ::~:~:: routines may hmJe to be changed to ;!!!...... : ~ ...... N_ ...... c_~~c .. O.. ~~~Q~!O .. ~ .... ~ .. _! .. :;!;~ ... ! 622 IF T$ .. " " THEN 628 .... u ...... u .. "_.O_,,_._~U .. _.U.N .. UN.U ..... " .. "" ... u,, .. u .. "" ~:e~:~~;:a~ IN/Our for your machine, and that the ...... "w.~ ...... * .. ~ 624S$·5$&T$ ow ...... ~ ...... o._ • •••••• . ... o·_· _____ ...... ~ __ N .. NN .... u N...... ___ ••••_...... 0 ... "' ...... " .. _ ~"' '"..,..,..,"" program always plays a perfect game ...... N 626 IF LEN( 5$ ) • 52 THEN 632 ------_...... 628 NEXT 53 ...... -RZ ...... 0_ ...... _ ...... _ ...... , ...... _ ...... _ .. _ ...... 6305$·"" Reader Servtc8 ------...... -.. ----- ...... , .. ..,"' .. ~~ .. .., ...... 632 RETURN ------~------634 REM ••••••••••••••••••••••••••••••••••••••••••• 636 Rei 700 REM ••• NEXl' KEY WCRD SUBROUTINE •••••••••••••• MOOVINGt 702 REM RETIlRNS IN SS THE NEXT KEY WOIlD IN 704 REM L$(I), STARTING AT POSITION 51, AND IMPORTANT 706 REM SKIPPING STRINGS DELIMITED BY QUOTATION 708 REM MARKS (USING FLAG Q). ON EXIT, SO AND Ple_ advise us of address chllnges 60 daYI in ad· , , 710 REM 53 REPECTIVELY CONTAIN START AND vance /Ifld attach your magazine mailing IIIbeI here. . l , 712 REM FINISH POSITIONS OF 5$. SEARCH Pleese clip this notice and mail. or send ul I rfllson· - 714 REM FAILURE RETURNS 5$ .. " ". ~Ie faclimi.e ...... 716 REM · ...... ~$~:; 5 ~: ~ ! :~ ! E ~; C ~! :~:~:: ES!: ::~ :9 3 718 IF 51 > LEN(L$(l»-1 THEN 760 · . ~a~~~~~:~~:B:~:;,~~~::;~c ~~c~e~e~;~ec~~~~~~~::;c~;!C~ ~~~~::; 120 FOR SO .. 51 to LEN(L$(l»-1 :~~~;~~~~~;~::::i;;:;;:~~:~:~~=~:;::;,:~i=~~~e~B~Da~ Q$ TflEN 732 ¥ 728 Q .. I - Q Nlnoe (pleas.! pront ""'w 'nfOfm~t,onl • 730 GO TO 758 " 732 IF Q .. 1 THEN 758 Addren . 734 RESTORE ; . FOR t2 1 TO 10 0 --- C,ty 7J8 'FAO US • ~ '"740 : ;§." POLLOWING 2 STATEMENTS ENHANCE • • .0 @!ft.@ 742 ""'EM SPEED - HAY BE CHITTED Stllt~ Z'p Code ~\ I~ 744 SO SST(U$,I,I) ... 746 IF S$ <> V$ THEN 756 ·---.- .... 748 SI .. SO Countty 750 52 .. LEN(U$) ...... _...... - .... - - ...... -...... 152 casus 600 ;~ii3~:: =~:~; :~! ! :~!~!~ ~ !: ;E~;~:~ -ao-...... -_~.~.a ... M ... OW~~Mow .. a~~Mowo .. _~~~~_!_w~oa_!o I>~ corporations, it was possible to ignore negative myths about Science Fact which was publisherl: in 1977. computers. At that time, very few of us got to see one up close , and even fewer of us got to use one. As regular readers Min is about to create a new companion for himself on his of this magazine know, all that has changed thanks to the native planet, a companion who will rival and vie with him not advent of the microprocessor. This device not only ushered in for natural resources, but ror intellectual supremacy. Man, the an era of improved cost and performance for hundreds of undisputed master orthe earth, mly berore too long hive to step home appliances, but made the low -cost personal computer graceruUy aside and yield the reins or power to beings or his own a reality. In 1978 more than 150,000 personal computers were creation. ~., . . purchased in the United States alone. it is estimated tha t 35% This message has made its appearance off and on for the last of these machines are located in schools. In 1979 the sales of In the next issue 0/ Re, the authors o/tltis article will begin a twenty years. Any inleiUgent computer expert would point these computers has continued to accelerate. Within a few column on "Computers &: Society." This new RC feature out that the word "intellect" means something completely requires a lot of reader participation. David and Betty want to years home computers will be as commonplace as color tele. vision sets. The possibility of vast communication networks is different in the context of machines than it does in people, address the issues of how the microcomputer can affect our but what does someone who is "computer illiterate" think lives now and in the future. Send your seed ideas to the suggested by this potential market. If the future use of such when reading this? ma~;ne with the name "Computers &: Society" on your networks is to be decided by the public for the public good, communications. What are your visions? Let them hear from we can iU afford to have many people holding negative views Considering the bad press givep to computers, it is a miracle of computers based upon miSinformation. All people must ~ - w that only 50 percent of the public fears them. Yet there is an become sufficiently computer literate to understand and to urgent need for the majority of people to understand that a participate in determining the role of computers in our computer is just another madtine which can be used to assist society. Computer anxiety must be overcome. 40 RECREATIONAL COMPUTING ConrinutJd on pg. 3' JAN .FEB 1980 " PLOTTING THE NOTES Let's go on with the once-promised So let's begin to integrate this with the "seeing what you hear and hearing what sound part of our program. First of all Bar Lines you see." enter the sound part of the program listed S€E W-n~T 'rOll HEJ:\R & in the beginning of this article. ADDING A STA FF Now add the following lines to the pro gram : To begin with I'll introduce a program 19 PLOT 10,8 section which gives us a diagram of a mu· 29 PLOT 13,8 sical staff to which we can then add 39 PLOT 16,8 Note-+CCCC AAGEEDD C - notes. The following section should 48 CO LOR 2 A o • draw the five lines of the staff and add 49 PLOT 19, I I Quarter Note • 78 COLOR I (gets one beat) - 42 RECREATIONAL COMPUTING a So why all this talk about integers and Line 230 is telling the computer to pick For the graphics part of the program: random numbers? Well, the other :lay at random, one of the 256 notes available while I was out working in my garden, and then play it on voice NO. Line 228 changes the graphics mode to I was whistling "Ole Macdonald" and clear the screen of the staff. this little space ship about the size of a Line 231 is making voice Nt playa note Line 232 tells the machine to pick a lea saucer landed next to one of the to at a frequency very close to voice NO. random color from the 16 colors avail As the chess game draws closer /0 end stralegy, if "aTUrally mato plants and some little green This is what causes the wavy sound you able. becomes more intense. In Parr V. Che/berg "lid Watters creatures- with funny antenna type hear in some of the notes. lines 233 and 234 combined with line continue middle game strategy, then toke all piece deve/op ears jumped out and began to "sing" 237 tell the computer to plot a random ment, offense and, finally, end stralegy. By 'his lime ill the along. The best approximation I could line 235 tells the machine to playa note point in one of the 20 columns and 40 sen'es, the articles logether are proving to be fine source mOfe. get of what it all came out like was to with a value of twice NO. rows available in graphics mode 3. a New n'o/ for dt:Ve/oping your own chess programs. _ TD make the following additions to the pro Line 250 tells the machine to start the gram we've been using. Line 236 tells it 10 playa note with a program again at line I. value of three limes voice NO. 228 GR. 3 SUMMARY 229 FOR Q - t TO)oo If you remember from my last article, 230 NO" INT (256*RND (I» the lower the note value on the ATARI If you're feeling somewhat overwhelmed 23JNI "'NO+t computer, the higher the frequency of by all this, don't worry. It will make 232 COLOR INT(l6*RND (I» the note. That is, a note value of JO more sense if you experiment with it, A lgorithm for C hess 233 U "INT(40*RND ( I» is actuall y going to playa higher note so that you can understand it in your 234 V = INT(20*RND(I» own way. I'm fInding that gelling the 235 N2" NO*2:GOSUB 6000 than say a value 25 is going to play. In this article we will be continuing the description of the 236 N)-Nt*):Y .. JOO:GOSUB6400 So in fact , voice N2 is playing a lower computer to do things is as much a }lro middle game strategy. Our last article dealt with the dynamic cess of experimentation as one of under 237 PLOT U.V note than voice NO and voice N3 is aspect of the game, and this one will deal with the static 240 NESTQ playing a lower note yet. standing. Or you might say that the PA RT V: MIDDLE GAME STRA TE GY evaluation. After the program has evaluated the dynamic 250 GOTQ I understanding comes from experiment. THE STATIC EVALUATION POSition, the cumulative values that have been assigned to ing. So keep trying and be sure to let each move are examined. If a clear-cut favorite exists, that me hear about any ideas for improve BY DAVID CHELBERG A ND DAVID WATTERS move is immediately made. If several moves are considered ments you might have. to be beller than the rest, only those moves are examined and the remainder are discarded in the interest of saving time. If all values are relatively close, all moves are evaluated statically. As a general principle, static considerations are of much less importance than dynamic ones. Any individual static con sideration is not worth the sacrifice of a pawn or the equiva. TRS 80 SOFTWARE DIRECTORY lent material loss. As a cumula:ive value obtained from this section, the average value aSS igned to a good positional move is about .8, as compared to a I for a 'pawn capture. Poor posi THE ESSENTIAL GUIDE TO OVER 5000 T RS 80 PR OG RAMS tional moves can be reduced as much as 1.5 in value . The following is a deSCription of the static evaluation sections • ALPHABETIZED & CR OSS INDE XED • INDEXED BY VENDORS and the relative weights of each. The section capable of assign • INDEXED BY TiTlE • 385 VENDORS NAMES & ADDRESSES ing the highest possible value is "attack." This section reo • INDEXED BY SUBJECT • OVER 120 PAGES sembles its dynamic counterpart in that it considers moves • INDEXED BY BASIC • PUBLISHED SPRING ·SUMMER ·FALL that the computer can make to attack its opponent. It is .appropriately included in the static evaluation section because the moves are not in response to danger, or direct material SO ME OF OUR CUSTOMERS INCLUDE : gain but rather, are aimed at piece development and at keeping the Opponent on the defensive. An US NAVY RADIO SHACK TANDY In the attack routine we are careful not to reuse any of the IBM US AIR FORCE PEPSI COLA DOCTORS attacks which were evaluated as counterattack measures in the NBC UNION CARBIDE TEXAS INSTRUMENT INDIVIDUALS dynamic protection routine. If the attacking pieces are as signed their common chess value divided by a fixed amount, our weighting process 'can be understOOd. This method is NO CHARGE TO ANY DISTRIBUTORS TO LIST SOFTWARE - SEND US YOUR CATALOG inappropriate for kings though, because it would give a dis proportionate weight to king attacks if it were used. This is Singl e Iss ue $6.00 +- A ~ Single Foreign Orders Add $2.00 Air poor playing for the computer since it would often waste many moves. Instead, attacks on kings are given a flat-rate Subscription $15.00 (3 issues) Comvu L""1 Subscription Foreign Orders Add $6.00 Air value that is slightly less than the value given for attacking a ,r d .." queen. It cannot be emphasized enough that random attacks are often more detrimental to the computer's position than BOX 1664 DEPT. R LAKE HAVASU AZ 86403 602·855·3357 helpful. That is why many other factors are considered in the static evaluation. 44 RECREATIONAL COMPUTING JAN·FEe 1980 OFFENSE PIECE DEVELOPMENT The next most vital section is offense. One of the most useful The next most important section is piece development. One of Static Evaluation Flow Chart features later in the game is to have your rooks controlling the fundamental rules of middle game strategy involves putting open ranks. Good values are given to moving rooks and queens your pieces into controlling positions on the board. This is to open ranks as well as moving pawns off of these ranks to 2. Move to open rank + accomplished by moving them off the back rank. In middle Move to consider prepare for later control. This preparation is closely regulated I 3. AUacks squarts around enemy king + game strategy, our primary concern is the development of by checking for doubling of pawns. Attacking values + I bishops and knights: the major pieces should not be used until I Defensive measures later in the game. Bishops can be developed by moving them Another important offense is a coordinated attack centered on Development values I. Protects unprotected piece + to the center of the board or by fianchetto (N2). In either the opposing king. Pieces that can safely move within one J. Moves piece from back rank + 2. Moves to protected square + case, a pawn must be moved to permit the development. Good Halts advancin, enemy pawns + (sliding ~a1e) square of the opposing king or that can direct their attack to 2. Moves piece to back rank - 3. values are assigned to moving those pieces which stand in the 3. Prepares back rank piece to be developed + Move tlminates a pin + squares around the enemy king are given a good value. This is •• way of development. In developing the knight, bishops third is Hinders development - I an important section since it prevents a random attacking of •• the favored position since it commands most of the center and S. Optimal knight move + unguarded pieces. It promotes a coordinated drive for the allows the other pieces to develop. N·R3 places the knight in 6. Controls center + opposing king. Before this section was implemented, the an isolated position, while N·Q2 or N·K2 blocks the future 7. Repeat of move - computer's disoriented attack and lack of direction was very development of the queen and bishop. All four possible moves Makes pawn chain + evident. The section provides some semblance of plan for the •• Breaks pawn chain are better than staying on the back rank but N ·83 is given the - Good value found No clear good value 10.•• Doubles pawns - best value. It follows that any piece which is in a developed computer. I I II. Undoubles pawns + Make best move Can computer castle? position ought not to retreat to the back rank. Defensive moves are considered next. These moves include 12. Overextends pawns - halting enemy pawn advances, eliminating pins and protecting 13. Pawn tip two (P·K4, P-Q4) + Yes~ No Many of the considerations involved in piece development are Pawn tiP two (others) pieces. Halting pawn advances is done on a sliding scale - the I'. - I I directly related to center control. Our central strategy has twO Type of piece B,N>Q,R>P>K closer the pawn to the queening rank the higher the value IS. Castle Milke random aspects: controlling squares in the center is the greater, while I choice from assigned to stopping it. Eliminating pins is accomplished by general positioning is the lesser. (See accompanying figure.) in Offense values the best moves. looking al a list of pins compiled earlier at the time the "black the middle game, the maximum stress rests on the four middle I. Prepares open rank + list" of vita l protectors was compiled. If the piece behind the squares, and they should be guarded to the utmost. pinned piece can move out, the move is given a good value. Another problem of piece development involves readiness. The last defensive goal is to keep as many pieces as possible All pieces ought to be developed properly, not just one side protected. This enhances the stability of the computer's of the board, or a select group of pieces. Every piece should be Center Control Values position. There are two types of moves in this category: those ready to take its place ill the action. One move ought to bring moves that protect an unguarded piece, and those that move • it to the center. So often, in a game of chess, this is not the an unprotected piece to a guarded square. Both types are given case. In some cases this is due to the fact that the same pieces good values. are being moved over and over again. Therefore, we assign 1 0 0 .02 .05 .05 .02 0 0 negative values to moving the same piece successively. At this point all moves are compared. If there is no clear decision that can be made with all the factors described to 0 0 Another cause for slow development is the overmovement this point now (no cumulative value above I), the computer 2 0 0 .02 .05 .05 .02 of pawns. For tijis reason, we devote a major section of our will consider castling. It generally tries king's side castling static evaluation to pawn structure. In this section of our first. If it cannot castle king's side, it attempts queen's side. program, the main goal is to form chains of protected pawns. There is room for inlprovement in this strategy. We have been 3 .03 .03 .05 08 .08 .05 .03 .03 The ideal chain resembles an inveT!ed "V." Once a chain considering a castling evaluator to determine if the pawn has been established, there is little need to move those pawns struct ure is more favorable for castling on a specific side. This again. Chains should not block those squares attacked by would also take inlo account the safety of the computer's king .04 .04 bishops. [n order to be able to form stable pawn chains, bad 4 .04 .04 .06 .09 .09 .06 in both castled and uncastled positions. if the computer values are given to doubling of pawns as well as breaking cannot castle, it randomly chooses one among the moves with chains. And of course, appropriate good values are given to the undoubling of pawns and making chains. In the middle game it the highest value. 5 .04 .04 .06 .09 .09 .06 .04 .04 is unwise to overextend pawns, so pawn moves beyond the To summarize the static evaluation, values are assigned on the fifth rank are considered poor. Extending a move up two ranks basis of three major factors: development, offense and is also poor unless it forms a chain or performs some other defense. Every move is given a value on its developmental 6 .03 .03 .05 .08 .08 .05 .03 .03 useful function. However, in the opening, P · K4 and p.Q4 . features, whether good or bad. Offensive factors, although are good moves to make. assigned to only a few moves, probably provide the greatest potential for the computer. Defensive moves provide the least 0 In developing and moving pieces in the middle game, a general 7 0 0 .02 .05 .05 .02 0 and should only be made if the offensive edge will not be rule is to move your lesser·valued pieces more and avoid sacrificed. Defensive moves are important, though, in exposing your queen and higher-valued pieces to attack. This providing a solid foundation f~r the computer's attack. bias is built into our program as knight and bishop moves are 8 0 0 .02 .05 .05 .02 0 0 prefered to queen and rook moves, which are in tum prefered to pawn moves, which take precedence over king moves. 4 5 6 7 8 Moving the king should be avoided except when moving to 1 2 3 castle. JAN·FEB 46 RECREATIONAL COMPUTING 1980 47 END STRATEGY Another factor to consider is guarding against perpetual check. r If the computer can put the opponent in check, but cannot End strategy resembles middle strategy closely, using the accomplish anything constructive by it, then the negative same dynamic evaluation routine to fmd any obvious moves value given to moving the same piece successfully is greatly to be made, then continuing in a modified static evaluation. increased. If the computer is in a hopeless position, a draw by If the correct pieces are on the board, a "fonnula checkmate" repeated position might be desirable. An ineffective attack routine may be executed. Otherwise, the static evaluation is recognized by the fact that the same piece keeps mOving for middle strategy is expanded to include many other without a significant material gain. additional factors to help in deciding the move. In end strategy, care must be taken with respect to timing. Moves In another section, all moves are checked to ensure that they cannot be made out of sequence without wreaking hannful do not move into stalemate, unless the computer is desperately if not fatal damage. A thorough evaluation is needed to plot behind. This prevents ending the game unexpectedly. The final the end game course. aspect of our end strategy is formula checkmates. In the event that a select group of pieces are on the board, a checkmating In the end strategy evaluation, the emphasis is no longer on procedure is possible. We currently have either in operation or piece development. It is hoped by this time that all pieces planning king-queen, two rooks, and king-rook checkma tes. are satisfactorily developed. Ideally, offense and defense We could write individual programs to perform each algorithm, should be in balance. The computer should not send a and others too, but we are looking for a way to combine them kamikaze attack on the opponent while leaving its own king in all into a generalized fonnula in orde r to conserve space. open danger. Neither should it surround in kind with all its piet:es like cowboys defending against an Indian attack. The In practice, the middle game static evaluation has led to very computer should create a balance between offense and stable and well designed positions for the computer. One defense, altering this balance somewhat in response to who is shortcoming in this section is that the computer plays a bit too leading. In our present program, however, the defense out· defensively. We have tried to correct this with our attack and weighs the offense. This is because defensive considerations coordinated king attack sections, however, there is still room are much easier to generalize than offensive ones and we have for improvemenl. Our end strategy seCl ion is still in develop had difficulty detennining a set of guidelines for an effective ment stages, but the general rules outlined above have been attack. Our end strategy is not as strong as we would like it to working well. The problem we are concentrating on now is a be, but we are continuing to improve this area. way of generali zing the various methods of checkmate, and how to press a material advantage. When these sections are --_/ In our present version, these are the offensive considerations: completed we fee l that they will greatly enhance our eliminate opponent escape squares; advance pawns; and pin program's end strategy and overall playing ab ili ty. the opposing king. Eliminlting escape squares is an expansion of the middle strategy section which attacks squares around Generalized principles for the computer to follow are quite the king. It restricts the mobility of the opposing king and difficult to program. However, in the initial way we have hopefully prepares for the kill (checkmate). Advancing pawns implemented this in our program at present, these principles conflicts with the middle strategy directive of halting have shown to be very effective in forming a consistent advances. However, it is hoped at tlLis time that the computer defensive strategy and a plan for offensive action. Experience has suffiCiently developed its pieces to support a pawn with our program has shown them to be indispensible. advance. Piece development is active in this area as are center "' control and retreat prevention. Placing the opposing king in a Our next article will analyze a sanlple game. We will have the pinned or forked poSition is a means of gaining "free" opportunity to demonstra te that our program actually does The Outside Connection material. Any material gain possible should be taken advantage what we say. In addition, we will give our outlook on the of by the leading side. The computer is encouraged to make future of chess programming for the rest ri cted user, and our trades when it's ahead and discouraged from making them views on how a home computer with limited space might be The Road Out BY DOC PLUMBER AND SON, INK, wlten it's behind. used to implement some of the major features of our program. We will not be able to publish a listing of our program since it Defensively, the computer has several factors to conside r. would double the length of the magaz.ine. Portions of the First, the king should always have an escape square. Pawn listing may appear. The ''Plumber'' family is growing. ' We now have Doc Plumber structure is closely examined here to guard against exposing and .Son showing you how to connect your TRS-80 to the the king. If the king is on the back rank, which is usually the outSIde world. case, that rank should be guarded by a rook or queen to prevent the common back-rank-mating trap. To expand the Doc (and Son) tell us this issue about an interface card that notion of having every piece protected at all times, advancing plugs directly in~o the back of the TRS-80 expallsion interface pawns can be protected by other pawns. In an effort to port. In future Issues, they will discuss particular applications control the rank, rooks are used to help the pawn. ----t'--'''''==:''-'- the! have developed that use the interface card. What s that nOls.e' I believe I heor an electn'c lTa;n whistle ... and a radIo: .. and 1 smell fresh coffee! The Plumbers have a lot of SUrpnses for us ... look for them. _ RZ -, ~ 48 RECREATIONAL COMPUTING JAN·FEB 1980 49 HUH Electronics (acquired by California Computer Systems, As you might imagine , there is no way to perfectly match the The TRS·80 is not the easiest computer to connect to t~,e 309 Laurelwood Road, Santa Clara, CA 95050) has produced two systems. But the design or the MINI-S] 00 does a remark· outside world, but there are ways to do it. I wrote about one several versions of a device which will perrorm this matching ably good job. Do not rush out and indiscriminately buy of the ways (using the SOUN DWARE device) in the Nov.· runction. The version that we will be using is called the MINI- S-IOO boards and expect them all to work on the MINI·8100. Dec., Vol. 8, No.3, 1979 issue or RC. That device plugged I:::::::~:::2 4 6 8 10 12 14 16 18 20 22 24::::~: 26 28 30 32 34 :::136 38 40 8100. It was purchased in kit ronn and put together by a 15 Their user's manual (provided with the kit) lists 5·100 boards into the connection ordinarily used by the TRS·80's cassette year-old high school student (the Son in Doc Plumber and that have worked successfully. We will demonstrate the use of recorder. The recorder itself sits outside the computer and TRS·8040·Pin Edge Connector Son, Ink.). a rew or these in future articles. makes its connection to the TRS·80 through a port. In other words, the recorder "docks" at the TRS-80 Port Number 255, The MINI-8l00 has a 40 pin connector with attached ribbon As the user's manual states: the cassette plug-in point. The computer's bus (or group of paths) carries address, data cable that connects to the back of the TRS ·80 keyboard or and control signals necessary for the operation of the to the Screen Printer Port of the Expansion Interface Unit Basically there are two restrictions: AllY board which Port No. computer. of the TRS·SO. requires DMA (direct memory access) will not work alld 255 allY board that requests a wait-Slate longer than one I 0 =• I o • 0 0 • With a suitable connector that matches the 40 gold fingers, millisecond will also not work. The reason for both of OJ you can tap into the TRS-SO bus and send signals back and these is that the dynamiC memory refresh cycle (for tile forth. You can give the computer commands from your out TRS-80's dynamic memories) will be imerrupted for too Recorder side devices, and you can receive signals from the computer to long and the memory data will be lost. control your devices. 00000 000.0 Ribbon cable 10 So the two questions to ask of your prospective board supplier Le t's not get too lied up in technical details. The important 00'00'0 MINt·8100 are: Does this board use DMA? and Does this board request a The casse tte port is just one little connection and we can't point is that you COli connect your own external devices to the Connector to wait stale longer than one millisecond? If the answer to any of hook up more than one device. This time I want to tall< about TRS-80. Some manuracturers (other than Radio Shack) are TRS-80 Kevboard TRS·80 edge connector these quest ions is yes, then the board will not work in the how to connect several components to the TRS-80 at the making it easy to do this. MINI-8100/TRS-80 system. same time. Where do we do this? We don't want to tear the TRS·SO apart to get at the electronic paths inside the com Many products have appeared in the past that are used by We-II discuss our first application in the next issue. If you puter. You probably know where we have to look -the rear of computers which have a bus with 100 signal paths instead of You must furnish a power supply for the MINI -81 00 which in have any ideas or projects that you would like to see the keyboard. 40. This system is known as the S_I 00 bus. TIlese products turn supplies the necessary power fo r the S· J 00 boards that demonstrated , let us know. The Plumbers are waiting. include: graphic boards, memory boards, input/output you plug into the MINI -8 100. There are prOvisions for 4 On the back or the keyboard is a small plastic cover that prob· boards, speech recognition and synthesis boards, and music S-IOO slots on the MINI-SlOO board. ably keeps ralling off your unit. You may have even lost boards. The list goes on and on. more to come your's by now. To use all of these many userul products wilh the TRS-80, some method must be provided to make the 40 TRS-80 signal paths compatible with the 100 S· 100 signal paths. It 's like joining the tracks of a narrow gauge railroad with one of a T V P standard gauge. -0POW '0 00 e e e o A smelt removable cover Rear View of the TRS-80 Narrow SlIIndard Your Power Supply If you remove the cover, you will see a slot through which a Or, as a Plumber might see it , it's similar to joining a 2 inch portion of the printed circuit board (which holds most of the drain pipe to a 4 inch pipe. Only, it's not quite as easy. computer's electronic circuits) protrudes. lbis part of the printed circuit board is called an edge connector, for obvious reasons. It was designed for connection to the Radio Shack's Expansion Interface Unit. This unit is used to add memory and make connections to outside devices such as disk con , t trollers and printers. The Expansion Interrace is meant to be " 2' 4 " 4 S·100--I." used for Radio Shack external products and is relatively pipe pipe Slots expensive (approximately $300 without memory additions). The edge connector contains 40 gold "fingers" (or contacts) which connect to the many paths (or lines) over which the In this article and future articles, I will be discussing one of the MINI·8100 computer's signals pass. These paths are usually rererred to devices (called an interrace) used to make the two nonmatch as the computer's bus (or buss, whichever you prerer). ing systems "fit." 50 RECREATIONAL COMPUTING JAN .FEB 1980 51 - == Third, any modification of the absolute memory locations entering the program will alter the program memory map. This referred to above requires knowing the exact locations of the problem was solved by running a sequence of code which, tokens for the SET and RESET commands. This cannot be when the program is RUN, will allow Chain Walk to find the done a priori in a program intended for publication because appropriate memory locations (those containing a 130 or 131) New Ways to Use Set & Reset the addition or deletion of even one si ngle space by the person and to remember them for later use in executing the I com mand. In effect, when Chain Walk wakes up (is run), il first orients itself with respect to memory and then proceeds. This orientation requires approximately 25 seconds. Notice in the program listing that there is no statemenl number 130; we would not want to confuse Chain Walk, would we? TRS 80: Chain Walk Continu6d on pg. 54 LISTING BY GRADY EARLY 00010 CLEAR 100 : CLS Set character storage, clear screen, type 00020 OE'FINT A-Z : 0111 X(1000)' Y(1000) variables, dimension large arrays. 00030 1"' 1 : .1=17129 000"'0 IF PEEKC.1)-ll0 OR PEEK(J)=131 THEN 60 Find memory locations containing the Dr. Early is Q professor in the mathematics department at 000:'.10 J =J+ l : GO TO .0 SET and RESET tokens. Southwest Texas State Univenity. He presents, in this article, 00060 P( I ) =J : 1=1+1 : J"'J+l : IF 1<6 THEN .0 an interesting graphical use of the TRS-80 that highlights 00070 N=IOO : I1X " 1000 : W=O : OT"" : H= I : T~N Initialile simple variables. Features 00080 FOR 1=1 TO N : X(I)"'N-I : Y(I)-O : NEXT I Initialize queues. some "common and not-so-common programming tech 00090 XD(1)cO : XO(2l"'O : XD(3)=-1 : XO(4)"'1 niques. " 00100 Y{lel)"-l : YO(2):1 : YOCl)"O : YO(")=O Initialile increment arrays and arrow Command 00110 FOR 1"1 TO. ! Ot ( I )"'CI(R'C90+I) : NEXT I character array. (Keyboard entry) Action 00120 RESETeX(T),Y(T» : T=T-l : IF T< 1 THEN T"'MX Professor Early has been using computers since 1963, alld cur 001-40 NH ""H-l : IF NH < l THEN NH:I1X rently is responsible for the Computer Science program al R Random walk. No operator control is 00150 X(NH)"X(H)tXD(Ofl : YCNH)"YCHHYlHI)f) : H=N H Move one step in current direction, OT. SWTSU in San Marcos, Texas. I can't stop myse/tlrom what's necessary. 00160 I F" X(H)127 THEN X(H)=O : GO TO 180 Wrap around screen if necessary. Strobe coming next . .. what happens to students who are late to 00170 IF X(H) 52 RECREATIONAL COMPUTING JAN ·FEB 1980 .53 - --.... Overpopulation, inflation, fuel shortages, poverty, hunger. The problems of ttm ~Iication the world can be over whelming, especially when Reviews is available in there is no end in sight. microfoflll But now there is a solution. Please send me additional Information. University Microfilms International ~ (Q) [)""~ [N] ~ g: ~ TEMPLE OF APSHAf By Automated Simulations 300 North Zeeb Road 18 Bedford Row Dept. P. A. Dept. P.A. (Q) fl1J IF ~ IRl P. O. Box 4232 Ann Arbor, MI 48106 London, WC 1A 4EJ Mountain View, CA 94040 U.S.A. England A century"S progress In $24.95 ~[pl~~~ transportal/on Replace line 2190 with: This game is one in the DUNJONQUEST Institution be written to display the INPUT requests series by Automated Simulations. It in a more attractive manner; it's strictly Street 2190 J "' INT(6·RND(TI»+tNT(RND is a solilare Dungeon and Dragon type a teletype·style display as is. It takes (·TI»+ I CUyN.m~~~~ ~~~~~~~~~~~~ si mulation game, with the PET acting as 2191 j - J+INT{6·RND(TI»+INT State ______Zip ____ There is a group of a LONG time to load via the cassette people working to mold the dungeon master. In this game, the deck. Commodore's speedy 500 BPS (RND(·TI»+I the future of humankind player controls or is a character that tape deck is to blame for this. Th.is pro· 2192 j - j+INT(6·RND(TI)+ tNT - a future they believe moves through a series of rooms search. gram begs for a noppy disk! (RND(·Tt»+1 2193 RETURN lies off the surface of ing for treasure, somewhat as in AD· VENTURE, but with much more com. ContinUfld from pg. 53 the planet in outer The instructions for loading state: "Al· Doing any debugging or modification is a space. plexity involved. You are given a charac. though the program is designed for the real pain, due to the programmer's Data Definitions ter at the beginning with 6 familiar at. new PET, you should experience no style, and the length and complexity of tributes - Intelligence, Intuition, Ego, difficuhy in running it on an old, ex· this program. There's a jillion COSUBs, Variable Us~e Strength, Constitution, and Dexterity panded PET, other than reversed upper COTOs, IF ·THEN::., DIMs , POKES , FOR or you can design your own. You then N Number of links in the chain; initialized and lower case characters." This state· loops, and an incredible number of vari· at 100. have your choice of 4 levels of increasing ment is totally, absolutely and complete· abies. difficulty. Each level has 56 to 60 rooms Iy wrong! A Level f PET has nothing MX Maximum number of links allowed; Srl,1r Power Satetl'le on it, with 23 different Monsters possible, but problems, some of them very weird, On the positive side, this program runs • 1000. a total of 80 treasures, and a whole raft and beyond understanding. If you change OK in a friend's Level fI PET. It appears of various traps, magical items, hidden X,V Circular queues for link coordinates. all the upper/lower case characters, some that the authors never tried it out on a doors, and other items. INPUT statements won't accept any· The l-5 News provides Level I PET, and assumed that the upper I XD, YD Anays of X, Y increments used to thing! At least one INPUT A$ statement information about the lower case character difference was I!cnerate new head link coordinates. A plan of the room is drawn on the requires the string to be entered twice. the only change needed, as many people latest developments in screen of the PET, showing treasures, On the second request for AS (after it do. Automated Simulations could make OT Direction of Travel (current). I = up, the aerospace industry walls, doors, and Monsters (if any). prints "n"), if you RETURN without more data tapes for more levels, and 2 • down, 3 " left, 4 " right. DT " 4 is as well as discerning initial direction. The screen is animated, and drawn in giving it any input, the PET will return sell them at a lower price (hopefully) comments about how large scale. Watching the PET draw the A$ = a! Under nomlal circumstances, this to addicts like me, who already own the they could affect your NO Proposed new direction of travel. Cannol rooms is entertainment in itself! There would cause the PET to drop out of basic game and instruction book. I'd future. be 180 degree reversal. are 18 commands available. BASIC. I relocated two INPUT Jines to buy them all! p Array of memory locations containing Space colony drawn /rom the end of the program, and went GO· the SET and RESET tokens. actual designs The complexity of this game is incred· SUB to them, and that cured those This is not a game for the 8·years·olds ible! You can keep playing this game problems. to play, because the rules are complex, H, T Index of head and tail. respectively, of literally for days before you explore each and it takes several hours to playa mean chain in the X, Y queues. room and get all the Treasures. Your $20 membership in There's a ton of INT(RND(O)) statements ingful round of Dunjonquesl. A weekend w Set to 0 for contfoUed walk; to I for in this program. In the new PETs this is can pass unnoticed when you get involved cludes a subscription to For $24.95 you get a tape (program on random walle:. the l-S News, merchandise O.K. In the old PETs, this is a No·No! in this game. one side, a data tape for the 4 levels discounts, mailings from Level I RND(O) always returns the same OS CUrrent command (scalar variable); on the other side) and a 56 page booklet. the legislative Information number, so you find yourself playing I .wholly recommend this game, because Codes for arrows (array variable). The instruction booklet is very well Service, and a brighter exactly the same game over and over it is a well designed, absorbing and written, and is the best I have ever seen ML Temporary variable used to indicate the looking tomorrow. again. You must go through the entire exciting game. A masterpiece of Level H number of links to be added or deleted for a computer game. The operating program , and change all those Os (about programming. WARNING! Extremely ad during execution of the D or M com· program occupies 24K, and the data 30) to a positive value. A bigger problem mands. dictive and time· consuming. Not for occupies another 6.5K, SO only a 32K is the dice.rolling subroutine in line the faint of heart or married. (My wife 11,12 Values of tokens (130 and 131) used to Please send orders to: L -5 Society PET can run this game. 2190. TILis simulates throwing 3 dice HATES this game!) reverse SET and RESET during execu. 1060 E. Elm 5 1. to get a number between 3 and 18. tion of an I command. Tucson, AZ 8571 9 There are a few criticisms, though. The After fooling around for about 2 hOUTS, Reviewed by David Conley first part of the operating program could I finally came up with a fix: Santee, CA 54 RECREATIONAL COMPUT ING JAN·FEB '980 55 ~------~1 •..•• *.* *. ******************************************************** PROBLEM #2 PALINDROME NUMERALS PROBLEM .# 3 (a ) N TO THE N TO TH E N These are palindromes: 121,747,606, 12321,3773 . N TIlese aren't palindromes: J 23, 76, 5049, 37,3774 If N IS a positive integer then NN is also a positive integer. NN A pali~drome is something that reads the same from right to Hmmm ... we can read N in two ways. Jeft as 11 does from left to right. ,...:::..;;...------...... 1. NNtotheN_INNjN (we will use this meaning ...... ::: ...... N ~/ In BASIC, we would write ..... , ...... '23' is not a palindrome! 2. NtolheNN_NIN j itNtlNtNJ...... , ...... But ' 2~ ' i~ the decimal numeral for the number whose English Here are some examples: ~----'"' """'- BY BOB ALBRECHT AND DON ALBERS nam.e IS twenty three: Hmmm ... that number is called 'drel und zwanzeig' in German. It is also called '212' in base 3. 1. l" . ,fl 'I _". , '212' (base 3) is a palindrome! 2. 222.2(22) _~ " '6 ~II" .,-, PROBLEM # 1 POSI TI VE, NEGATIVE OR ZERO 3 3 1/ \ Gets big fest. 3. 33 .. 3 13 ) - 3 27 -1,625,597,484,987 f)r ( doesn't il?1 .\ Aha! A number is a number, but the name of a number 4. 444 .. 4(44, _ 4258 .. ??? An easy problem. All we want is a program that asks for a mayor may not be a palindrome. ,,, \J '" number, then tells you something about the number. I. 27 (base 10) is not a palindrome. That's pro.blem # 3(a). Compute the exact value of 444. It If you enter a positive number, the computer tells you: ?7 (ba~e IO~ "',11011 (base 2) = 33 (base 8) can be wntlen as a decimal numeral with ISS digits. If you 110]] and 33 are palindromes. YOUR NUMBER IS POSITIVE wish, Iry 5 55 or 666 or ... , If you enter a negative number, the computer tells you: 2. 12 I (base 10) is a palindrome. YOUR NUMBER IS NEGATIVE !21 !b~se 10), = I ~ J II, (base 3) = 232 (base 7) PROBLEM #3(b) HOW MAN Y DI GITS IN NNN 121 , 1 1 III and 232 are palindromes. If you enter the number zero (0), the computer tells you: Write a program to: Here comes problem 3 (b). How many digits does the YOUR NUMBER IS ZERO NN . exfX!"ded form of N have, If the number is expanded in I. Ask for the decimal name of an integer in the A solution to this problem is shown below, in TRS-80 BASIC , deCImal? range 1 to 999999. (Reject all other numbers) A /lew feature for the magazine! Problems for YOII to ponder, a version of Microsoft™ BASIC. With minor editing it will puzzle owr, program, ulld take pleasure i/l solving. The Dragon run on the APPLE, ATARI, PET and several other computers. The expended form has' digit. 2. Show al! bases 2 through 10 in which the numeral for the (Bob Albrecht) and Don A/bers promise thaI this section The expanded form has 2 digits. will become the number aile source of programming problems 100 REM"·PROBLEM #1 POSITIVE, NEGATIVE OR ZERO number entered in (I) is a palindrome. Also show the numeral in each base. for teachers. They encourage teachers to use these problems 110 REM'·'RECREATIONAL COMPUTING, JAN/FEB 1980 3. 333 .. 7,825,597,484,987 The expanded form has 13 digits. 120 CLS 4 in the clJJssroom to have students solve the problems and 4. The axpanded form of 44 has '55 digits. 3. If there is 110 palindrome numeral in a base 2 through 10 selld in solutions for publication. Of course, we encourage 300 REM"'ASK FOR A NUMBER, X 55 all of YOIl to give the problems a try. Some are easy, some are for the number entered in (I), show the message: NO PALIN 5. The expanded form of 5 hal 2185 digiti. Hmmm . .. does the 310 PRINT: INPUT "NUMBER, PLEASE" ; X DROME IN BASES 2 THROUGH 10. really difficult. Let s hear from everyone on this /lew set expanded form of 666 have too many digiti to be storod in the of chal/enges.! RZ memory of a home computer? 500 REM**'TELL WHETHER NUMBER IS POSITIVE, A RUN of your program might look like this. NEGATIVE OR ZERO We begin an ongoing series of programming problems for 510 IF X >0 THEN PRINT "YOUR NUMBER IS POSITIVE" YOUR NUMBER? 121 . Write a program to: 520 IF X < 0 THEN PRINT "YOUR NUMBER IS NEGATIVE" ~~W~h:"'::;'~'~h'./=-'-Ii'''-'-~''O$itive learners. tcachers. or anyone who likes 10 solve problems. Our 1 I III (BASE 2) IS A PALINDROME. integer for which this is true? 530 IF X = 0 THEN PR INT "YOUR NUMBER IS ZERO" problems will range from easy. to harder, to awful. 11ley will 232 (BASE 2) IS A PALINDROME. ,.A../V\~ 1. Alk for a positive in teger IN) in the range 1 to 9. be numbered 1,2,3,4,5 and so all . In fu ture issues, solutions 121 (BASE 10) IS A PALINDROME. "7 "'-: 2. snow the number of digits in the expanded form of NNN. to previously published problems will appear - we hope that 700 REM*"GOTO 'ASK FOR A NUMBER, X' 710 GOTO 310 YOUR NUMBE R? 1234 ,/ fiJ.., your solutions will appear. We also hope that you will send Quickly, without using a computer-how many digits in the NO PALINDROMES IN BASES 2 THROUGH problems for us to publish. 999 END I~ expanded form of 101O1O? YOUR NUMBER? 1000000 Some of the problcms in this scries (we won't te ll you wh ich Ha! We have pre-empted the solution which immediately SORRY. I PLA Y ONLY WITH INTEGERS, I TO 999999. ones!) will be used as subjects of "mini-tutorials" in future leaped to your mind. In fact, you can 'f use the IF statement issues. Thcsc tutorials will bedesigncd to help break "mind at alU Your program must "behave" exactly as ours, but YOUR NUMBER? 3.14159 PROBLEM .::: 4 VOLUME OF A POTATO sets" or "mental·roadblocks" or "computerized convenlional without any IF statements. SORR Y. I PLAY ONLY WITH INTEGERS, 1 TO 999999. wisdom" by showing unusual ways to solve problems. We We .hand ~ou a potato. We want the volume of the potato in hope that you will send unusua l solutions. We especially want And yes, old timers, BASIC experts and otllers, we know that YOUR NUMBER? and so on. cubIC cent~me ters. It could be any old (or new) potato. What solutions that make people say, " 111al'5 so simple (beautiful. do you do. How can your computer help? there is an obvious way to solve this problem, using a stale Acknowledgement: This problem and Ihe one that follows are elegant. etc.). Why didn't / think of that?" ment that begins with "0" and a function that begins with paraphrases of similar problems in Advanced Problems for "S". If you do it that way, you will be one of many. So Cor~Pllter Mathematics by Bob Albrecht, published by Di 'tal !he sag~ of the potato will continue in Re. Please send your And now, on to the first bunch of problems. Send your solu rethink! We gleefully await your unusual solutions. EqUipment Corporation. gI Ideas-given a po ta to and a computer, how can we obtain the tions 10 these problems; also send problems. volwne of the potato? 56 RECREATIONAL COMPUTING JAN-FE8 1980 57 .. , Commodore s PET is a factory-assembled you can make your PET go faster by being sent by Pony Express. Sounds like personal computer based on a 6502 issuing a POK E 59458,62. Now LIST a a cheaper and faster way to get COM to make the programs run on either old microprocessor. The original PET, m('del long program! (To restore the PET PUTE. Subscriptions can be ordered from or new ROM machines is somewhat 2001 -S, was a $795 system that included back to the normal mode, issue POKE COMPUTE, P.O. Box 5119 G a keyboard, cassette tape unit, built-in 59458,30.) Doing this on an 8K PET b NC ' reens- muddled and inconsistent. Just the same oro, 27403. All technical corres. ther Contain quite a bit of pleasan; TV screen, some graphics, upper and The Society of also makes things go faster, but the pondence can still be sent to Len lind ,,:hunsy, although the quality is not as lower case, extended SK BASIC, and PET Owners and Trainers screen blinks on and off in a very dis say, 1929 Northport Dr. #6 Mad,'so 8K of user memory. turbing fashion. WI 53704. ,n, h1gh as those from SoundwareorCURSOR. BY HARRY J, SAAL SPOT is devoted to the host of applica Did you know that the machine langu WORKBOOKS A light pen for the PET is available from tions ~ routine and wild - which PET age monitor supplied by Commodore is the 3G Company, Route 3, Box 28A, Gaston, O~~gon 97119, for $29.95 plus users have found for their nwchines, as in ROM on the new Pets? The manual There ar.e two new student workbooks $ I .50 . mailing and handling charge. well as to the nitty-gritty o[ repairs and indicates that you load it from tape, for begln~ers learning PET BASIC. modifications. In other words, almost but it's really there. One quick way to The light pen resembles a ballpOint 80th a~e 10 active classroom use, and pen, and plugs into the user port of the anything relating to the PET is fit materi start it up is to SYS(l024). Details about are deSigned to be used with the PET al for this colullln. Just send Harry using the monitor are in the User's PET. It teguires no:~temal power supply, at hand, yet don't need an instructor and adds an additIOnal dimenSion to your questions, idel1s, and tapes c/o Manual; remember that an X command They gently and effectively ~earby. ~mes and .grap~ic programs. This Iype of PCC He 1/ give each of them his car-:ful gets you back to BASIC . ~troduce the PET, starting with the attention. - TD light ~n is qwte simple, essentially reo eyboard. Cow Bay Computing Box s.pondmg to the presence or absence of We all know that programs which do 515, Manhasset, N.Y. 11030 has r;leased to the. PET. (See Prestodigitizer article HEARD AROUND THE QUA YSIDE . PEEKs and POKEs often work on one by DaVId Th~rnberg, this issue). Sanlple hgill. By displaying one or more flashing . Feet! me, I>". Your PET Computer for cursors on Ihe screen, and testing in soft . . model of the PET, but not on the other. beginners. It IS available for $495 d p~~~ams which Come with the Presto I was surprised to see a program which h . . ,an ~a~e whether the blinking of the cursor Commodore continues to make changes - digitizer tablet can recogn;'. -'IdJ th e num. .-. a.s a compamon book Looking Good - worked fine on an 8K PET have a totally ~s .10 ~ync with what the light pen sees, in its product line. The latest is the . . be.rs or letters when written on the laolet .- With Your PET for intennediates (also It IS slm~le to set up multiple choice or discontinuance of the original 2001·8 . .. ' messed up display format when run on S4.95), uSing the metal tipped stylus provided. - menu d~iven programs. The light pen I machine, with the built-in cassette tape a new PET , and there wasn't a PEEK or In fac~, YOLI can even train the PET to and small keyboard. In its place is the POKE to be found. There are changes in recogmze your own handwriting. This tested did not have polarizing plugs on A series of similar workbooks was devel I~e user port connector, and the orienta 2001 ·8N, which, except for memory size, BASIC itself to be wary of! One example oped at San Jose State University with handsomely packaged device comes \-/ith ~on . of the .. conneClor always seemed is identical to its bigger brothers that have way it was on the first 8 K PETs. It was is this little expression: typing ?SPC parallel for the PET, Appie and a useful manual, and cassette tape with editi~ns u~sldedown to me un til I placed 16 or 32K memory. In effect, it means a mistake to change it in the first place, (40);:?POS(0) on an old PET prints 40, several sample applications. It COsts TR~-~O. BeglOners can get starled with "th is Sl'd e up " sticker on the b k' a price increase for economy-minded but this will throw even more confusion and on the new PET prints O. What 1'rammg your Computer (PET edition). 548.50 plus $1.50 (and tax in Cafifomia) than this oversight, it is a very PET purchasers, since it costs an addi into the arena! changes have you run into? can be ordered either from Inno: Ot~er :~Ii Ten or more copies can be ordered from ~~ deSigned producl, and one that adds a tional $ 100 to get a tape cassette. What \lISIOn, or at local computer dealers. M.E!.RA Instruments, Inc., Pickering lot. of .enjoyment to the PET. Software you do get is the full·size keyboard, Lastly, Commodore is hard at work PET PUBLICA nONS DiVISion, 2056 Bering Drive San Jose is written for use by this light pen and the new corrected ROM set. on a "business" machine. The major Have you put sound on your PET yet? ~h.ich. CA 95131. for $2 each. Single copie~ IS avaIlable from several Sources. I found change is the use of a larger 80 character TIle PET Gazette is no longer. Len If not, the best way to go is to get Ule ~lay be ordered frolll Creative Publica the programs written by Quill Software Speaking of price changes, Commodore screen , and built-in floppy disks. (Sound Undsay's fine magazine has disappeared, Sou~dware adapter, from CAP Elec tiOns, P.O. Box 10328 Palo Alto CA 2512 Roblar Lane, Santa Clara, CA' has twice now made a super offer to like the Tandy TRS-80 Model II??). but is replaced by COMPUTE, The 94303, for $4 a copy.' , tromes, 1884 Schulman Avenue Sa 95051 .to be the best. The light pen is school systems, given them three mach Will it have a 6502 CPU, or a 6809 Journal for Progressive Computing. Issue Jose, CA 95124, or your local re'taile; best suited for a multiple choice scenario ines for the price of two. But recently, as several of the newer products now I, dated Fall 1979, is already out. It is PET INTERFACES for $~9 .95. It's very attractively packaged: such as in the game of Swords and the offer was abruptly shortened by under development elsewhere are ex a beautiful, slick 102 page magazine and mcludes a handy inStruction bOok Sorcery, Hunt the Wllmpus, or Olhello. 30 days. This caused havoc with many pected to have? TIle 6809 is a nice up with lots of good information and sources and demo tape. Even if you already made If ~ou are interested in interfacing any There are four tapes avilable frolll Quill PET dealers, who planned extensive ad grade from the 6502. It contains a series of products for the PET. Robert Lock, your own "CB2" sound box, get a hold deVIces t? your PET through the user pri.ced at about S20 each. I suggesl YO~ vertising and sales campaigns based on of 16 bit extensions to the current 8 President of Small System Services, of .the tapes from Soundware called port.' or In understanding how the CB2 them for a complete up-to-date Commodore's offer. It is stunts like this bit architecture of the 6500/6800 family, Inc., has put togcther a superb replace Action Pack, The Classics, and Word ~nte musIc works, you probably sJlOuld take list as new ones are made available that will cause the PET to lose the but to the outside world looks like an ment magazine, and has Len Lindsay as Each costs only $9.95, and con a look at Rodnay Zaks' "650'" A t: F~n. regularly. tio 80 k "/ . ~ ppuea- back..ing of its anny of supporters. 8 bit processor, so all standard peri his Senior Contributing Editor. As a ns o. t IS published by SYBEX ~ams three excellent programs with sound pheral ch.ips are still compatible. Com sign of how much work wenl into COM· 20~0 Milvia Sireet, Berkeley CA 94704' In~or~orated. They are well done, and qUitc mexpensive. Several other changes seem to be in the pared to a 6800 it is quite a bit faster; PUTE, someone managed to get Commo TIllS bo?k is ch~ck full of details on ali wind. Commodore is getting ready to unfortunately when compared to a dore to pay for 4 pages of advertising, a the V~TlOUS peTipheral chips that are CORRECTION first to my knowledge. release a new enclosure for the PET , 6502 running at the same speed it is used In the PET, and includes details Ot~er SOurces of interesting music tapes made of structural foam (li ke the Apple) pretty much even, although easier to about programming them in assembly (a.slde fro.m many of the fine programs In the Sept·Oct issue of RC, Harry write programs for. There is a change in orientation from the still ~omlng regularly from CURSOR rather than steel. The appearance of the .. The book costs $12.95 and is Saal wrote that the Melagame PET Gazette. More like MICRO, lanf~~e PET is somewhat "softened ," but other COM aval a e In most computer retail Slores. MagaZine) are the Allen Computer _Hunt ~as available from Computer wise unchanged. The PET and TI 99/4 PET TIPS PUTE plans to provide information Products Music Box I and Animation I Way In Madison , WI. However were the only two personal computers for all 6502 based machines, which in PET HARDWARE ADD -ONS tajJCs. These two tapes are available th.e aut~or of the game, Michaei tested by the FCC that meet the July You may have noticed that on the new cludes the Apple, KIM, SYM, AIM, at $10 each from Allen Computer Pro Ric.hter, Infonned us that it is realJy 1980 limits on RF interference. Let's PET even when you POKE characters 051 and the new Atari. You can sub· One of the more remarkable gadgets to ducts, 34844 Munger Drive Liv . avaIlable from: hope this change doesn't affect the to the screen there is no "snow." lltis scribe to The Journal for $9 for six issues put on a PET has been develo d b MI 48154. Each contains four' selec~~:; excellent shielding currently provided by same change permits the PET to print (one year). An alternative is a S7.50 Innovision. P.O. Box 1317 lo peAJ Y from Bach, Chopin and Mozart including Programma International, Inc. CA 94022 Th P , S tos, the metal case. Rumor also has it that characters or list programs much faster "personal/retail" subscription, where . e restodigitizertm t bl the Can -Can and Flight of the Bumbl 3400 Wilshire Blvd. than before, although Commodore's soft your copy is bulk delivered to a local bee. All eight programs have ,,~"', Los Angeles, CA 90010 Commodore will be switching the char attaches to the PET's. user po" ,an d'"can . d ~" sing acter generator on the PET back to the ware doesn't take advantage of il. But dealer for you to pick up, instead of be use d 10 prO\llde handwn", . anunate screen displays while the music (2/3) 384,0579 en Input plays. Unfortunately the author's attempt 58 RECREATIONAL COMPUTING JAN·FEB 59 ... 1 The, Line, 1080 to 1130 are reached only if no match was fourtd. PT14: NAME GENERATOR They print out a list of the IICceptable character•. PT 16: TRS -SO GRAPHICS CHARACTERS Line 1140 is reached only if the input was a cerrl~ return .. As part of e new gaml. called EAR TH QUEST. a routine was Programmer'S L· 1150 retums the value of this function ; I If It IS a carrtege Ine + 1 I"IHded to generate exotic namll of plllC" and ob}eicts. The This progrlm will put all the TRS·80 graphics on your screen. ToolboJtTM return, otherwi$8 the number of thi! matched charllCter . variable NL is Utt to valull of 2. 4. 6. or 8. CS contains the side by side with the ASCII codes (129 through 191) for each string "BCDFGHJKLMNPRSTVWYZ". V:S COnlains "AEIOU". character. You will see the graphics cheracters. eight per line. Finally, a few words on Northster BASIC; The routine woids Ob$cenitill in English. but persons who spelk double-spaced on the scrEltin so that you cen easily distinguish - one cheracter from enother. Old High Martian may be o ffended. The \ is the uatement separator, equlv. ",nt to : in other BASICs. k d 'nto 100 REM · "TRS·SO GRAPHICS CO DES AND CHAR . Line 1020; AS· INCHARSIO) puts the next ey pres$8 I 1000 REM PICK NAKE ACTERS AS it does not print it. It wilt accept control codes. 1010 FOR ['1 TO NL STEP 2 110 R EM .. · · PROGR AMME R·S TOO LB OX (TM) # 16 L.ines' 1060 an d "00'' BSII , I) gets the Ith cherl!Cter alone from 1020 C' RND (19)+( 120 RE M · · · RECRE ATION AL COMPUTING, JAN/ FE B BS It is equivalent to MI DSIBS, I, 1 I. 1030 N~([)=C~(C.C) 1980 Li ~e 1060; Northstar BASIC requires EXIT .to prematurely 1040 V= RND (5)+1 130 CLS terminate. a FORINEXT loop . Other BASICI lUll 1.1111. GOTO. . 1050 Hi(I+1)=Vi(V,V) The comma .In PR ' NT s "-ents""" i. the same .. a semicolon In 200 RE M · ··SHOW COOES AND CHARACT ERS ON THE other BASIC •. (060 NE XT [ SC REEN BY EVERYBODY BY LARRY HUDSON 1070 RETURN 210 FOR CODE. 129 TO 19 1 220 PRINT CODE CHRS ICOOE) STRINGS 12.32); BY JIM DAY 230 IF POSIO)" 0 THEN PRINT , , N 3 of PC, 1973. Mare LeBNn began. column that PT12: FACTORIAL ROUTI NE 240 NEXT COD E In Vo. , o . " ooIbo .. of providea fQUtinH that could be used IS part of a t x computer ,kill •. We revived that column in the MiIV-June 1979 This function and the one following. in PT13. are two more 300 REM ...... WA IT WHIL E ENRAPTURED WATCHER WA TCHES I"ue of Northstar BASIC routines. For a short and simple way.to com· Re. 310 GOTO 3 10 pute factorials, give this one a try. Refer to PT11 for Informa· Here '1"1 .0000e mort! "tool," for the Toolbox, Hope y~ can ~se . h~ Northstar BASIC correspond. to a lot of standard tlon on ~.. . If' r 999 END thH8 new program.• "vou have ideas for useful routine•• wnte-RZ BASICs. Warning: this routine iSl1l'Cursi....,-it c.Us Itse In Ine them down and Mnd them to 1,1 •• '01 PT15: LPR INTING BY POKEING Line 220 prints eXlICtly eight (B) characters each time it is I. ~DI rIoCTO~IAL "!OICTlO~ J51~r; ~O~I"St •• ·AS I~ eXlCuted. as 'hown below. ~: ~~r~~~"~~;~ A~ rLH Y_I'RfT JD~ Y .~ " '~A' ~ _ I)" There Is an easy Wily to direct material to the line printer. and ~A ~'I'JR~ y 220 PR INT CODE CHRSICODEj STRIN GS(2.32) PTl l: MENU SEL EC TOR I susPict it will work for YOUr Quick Printer 81 Will. I c.n·t take ~: ~~~~~ (\"RI~T " .~,"Io ",.~,.n. tha credit for d iscovering them, but they h~ helped me to 't t ,n DIll 5 charactars 1 graphic. Here i, e more elegant form of a "menu selector" the~ the u~el 11' I write progf8ffis that c.n be run on systems with atld withoulline 2 SPlICes ~I. 121 printers. Ispace. 3 digiti, character "Enter the number of the function deSlred·-. :hll r~tlne IAIo 362sne "'~) accepts any ,ingle character. compares it to an arbItrary lIst of ~R!. ~ •• J2"~U ' I. 49 1. 6 .M 2~1 •• E'~~ characters, and return. with a number which corre~ond' to the WheneYllr you want to lind deta to the printer. use the fOl lowing: 5 ... 1 + 2 .. B charl cters metchltd character. The return value can be used In an ON ... BY A.BLESSING GOTO ... Itatemant. If there is no match. a nicelY. formatted POKE 16414.141; POKE 16415.5 The TRS·SO·s screen width is 64 characters. So, Ifter printing lin of the acceptable characters is printed .. The r~tlne acce.pts eight codes end graphics characters. the TRS.BO rellCh&! the lower ClSe letters. Written as a multiple line defined function PT 13: ACKERMANN 'S FUNCTION right end of the scrftn and the Cursor moves to position zero in Northllar BASIC. the function can be easily converted to a Whenever YOU want to rtlstore sending data to the screen, UM thi.: (0) at the next line. simple subroutine or to other versions of BASIC. For those of you with a nEltid to compute e complex function that requires a routine to c.lI upon itself. here is I fine ~xample . POKE 16414,88 : POKE 16415,4 Ahal Now we III what li ne 230 doe-s. It prints atl empty Une Uti DEf IfHCUI Itt' I"UIII8U , In lines 40 atld 50. the function calls itself to continue the aft.. ewry eighth e)(ecutlon of li ne 220. Try the progrem If:.?9 1~'\A"IIl(HAR"')\IF iIt ~t.HII ' IIJJ IHEII \ 11 c.lculations. Line 50 is especially interesting. Some BAS ICs When the first instruction lil t is executed, th, computer thinQ without line 230 jUlt to 118 what hllPptn •. If U :" • IHEH U~. ElSE PUIII III "j. may not handle this kind of l1I'Cu"i...., operetion. so program_ that the line printer is the scr"n. so PR INT UatementJ act like BY THE DRAGON 1141 If AI _> ' , " IHE~ U~CHR " AS'(AU-J2) mers beware I US. fO~ I-I 10 I LPRINT statlments. The second set of statements restores leu If AI ~!l HI,I ) [HEll EXJI II::" the screen 81 the output device. Wh en YOU USI tho regullr J. ,.~ .. "C~lft". ~H· S TJNCTlO~ IISI" 60 RECREATIONAL COMPUTING JAN-FEB 1980 " F 1 Software for PET. Programs MicroGnome'. CAIWARe, A SOft. provide the PET with Computinll Teacha,. A high_ nineleen ware system for authoring and Research and DevelOPm&rlt Pro. functions, including: quali"". bi-monthlv journal for standard using Computer Ass isted Instruc_ ject. At University of Or'gon. to and custom ranumbering, com computer educatorl who wish to tion on the 16K TRS_SO with provide a non-threatening first pact, trace, append and merge, keep up with new developments Level II SASIC. CAIWARE is en eXperience with micros lor K .12 end additional disk end tepe re in the field in IIlsociation with eid, not a replacement for the Illachers. In the self· instructional, netionll group celled Computer lated functions. Tape or disk Illacher or the textbook. Pr09rarn labora tory.type Course. the learn. Ulinll Educato". Don McKali. $100, or on ROM for $200. il $24.95. Fire.ide ComPUting. er will use a PET and explore Independence MS, 1776 educa. Hard~re N8Iionaol Artificial Int'Jligence Inc ., 5843 Montgomery Road, more than 50 programs. Project Laboratory. p.O. Sox F, Mobile. tion Park Dr., San JOM, CA95133. Erne·Sure. InHllnlly erllS8S pre INTROL/X-l0 for Apple Com_ DunJonquest. A fantasy adventure Seientifie R.port. Computer as, Elkridge, MD 21227, (301) 796. director ,s Dan IselCson, Com. AL 36601. 1205) 433-5529. 4165. puter Center, Univ. of Oregon, ~IOU$ programs or recordings put.... IntrolfX,10 allows use .. series lor the T RS·80 and PET sisted resaarch report program on Cetalog of Microcomputer Pro. Eugene, OR 97403. from cassella', and Rapid Ae to remotely control 110 volt A.C. microcomputers, includes Temple avians (birds) for Apple II. EnjoY' gramming. A 32-page compen. EdUc:lltional Program Info,muion winder rewinds cassettes in jun el.ctrical devices bv commands of Ap~.i, Starlleet Orion and able and colorful pr09flm that dium lining over 300 programs Cenmr (EPIC) hes been estab secpnds. Produce quality record sent over eileiuing building wiring. Invasion Orion. Cassetta or disk, Illaches about birds. Purchase for PET, Apple, and TRS.80 Ings, save wear on equipment. lished by the Apple education Up to 16 remote modules mav $19.95 .nd $24.95 from Auto, supports rt!search. $10 for two microcomputers, covering uses Each is $24.50 plus $1.50 ship progrems. American Avicultural, Foundetion to encourage the pro. be controlled. Base unit $279. meted Simulations, P.O. SOile from science, education, end bus. ping. Magnesonics Sales, P.O. 326S Watson Road, Seint Louis. duction and UI8 of microcom. Mountain Hardware, Inc.. 300 4232, Mountein View, CA Educational inelS to entertainment and use in 80K 758, VeM.... a, CA 93001, MO 63139, (3'4) 645·4431 . puter·based leaming malllriali. Harvey West S lvd .. Santa Cruz, 94040. the home. Inqu ire .t COmputer (805) 642·3092, For more informetion: EPIC CA 95060. stOr&$ o. write Instant Soft. Oak inS PrOlll1lmminll Aid.. A Review, Apple Education Foun. Software wore Inc., Calliog Dept., Peter. Siringy Floppy Mass Storage Skyl .. PAL. This is a high-per Classic Gemes Seri8l. A series of package of seven programming dation, 20605 Lezeneo Driva, borough, NH 03458. System. HIgh performance syuem lormance serial prinl8r featuring machine lenguage software for the aids meinly for Apple II. Includes Educetional Softw.r, Sari" For Cupertino, CA 95014. SpeCial! for micros. Suitabie for numerous 40 character-per-second printing TRS,SO. FUtures SACK·40, our Lister, Peeker, Cruncher, Dilketlll the PET, Apple II, and TRS-80. applications. Package inCludes with a full 96 character set. Full Sackgemmon program, Z-Chess Copy, Prompter, Calculator end Three new titles: drive unit, tape heads, ooereting line buffering and bidirectional and Dr. Ch,ps with graphic dis· Text File Copy. Price is $39.95. R6Bdlng Comp,."h6nsion: What's A FILM) One Pa$$, Inc. is program, elc. Base system peck· look·ahead printing,S x 7 dot play of unrivaled quality. clarity Visit dealer or contact Dakin5 Dlfffuent? presents logical pro pleased to announce that the film '!Ie '$ $249_50. Exatron, 3555 matrix. $450. Skvles Electric and ease of play. $14.96 and Corporation, 7475 Dekin Street, blems; Minicrollword builds vo. "Don't BOther Me, I'm Learning" Ryder 51., Sanla Cla.e, CA Works, 10301 Stonydale Drivtl. 517.95. The Software Associa· Suite 507, Denver, CO 80221, cabulary and spelling skills; Word Other will be shown over the Public 95051, (408) 737·7111. Cupertino. CA 95014 (408) tion. P.O. BOile 58365, DePt. RC, 1303)426·6090. Skill, ' -Pref,x'J presents com BrOadclilSting Network on Sunday, 736,7S91. Hounon, T X 7705S 1713) 4S2, mon prefixes end the words Januery 6, 1980 et 6:00 p.m. This they appear in. Grtater Baltimor. Hambo,ae .nd Double oensitv Floppy D isk 08S3. Business Softw.re Pack'll". For Publications timely production will present a CompuNrllll1. An electronic ex. (n'triKe. A component that the TRS·80 Model II compUlllr. From computer stores or Pro fescinating view of the micro gram Design, 11 Ider perimenters ~ow end .wapfest, enhances exiSling disk storage Softw.r. Library. A set of fifty EXlensivelv modified progr...... s to Court, TRS·BO Softwtre Souroa Direct_ electronic rtlvoJution and its im_ Greenwich, CT 06830, will be held on Sunday, March 30, cllplH:ilies with only minimum re· programs consisting of games, use expanded hardware capabili· (203) P8Ct on the leaming process of 661·S799. ory. ComputerMat lins over 5,000 1980 at the Me rylend Stete Fair. configuration of 8)(ining 'Y$tems. teaching programs end practical ties. Send $ 10 for each manual, children. TRS·SO loitware programs thet grounds at Timonium . Excitinll BASIC inpUt/outPut system soft applications. Includad art! Trek 3, and two SASE's lor cetalongs. are aveilable from over 380 MICRO·REDY project. computer displavl and eXhibits, ware for CP/M on single-density Backgammon, Checkbook, Con· Micro Architect, 96 Dothan St., A feder_ vendors. Designed to help 'ocate This litm was taped al the Soft~re ally funded effort to deela.. .nd hobbyists, dOOr diskette. With BIOS for CP/M ondrum, Arena and Calendar. Arlington, MA 02174 . softwartl for home, educational, Lawrence Hall of Science in computer IInifled instruction for prins, etc. For Information or on diskette, priced at $425. Hardcopy Graphics Pr09ram. This Introductory special $49.95 on """"" personal and profeuionel areas. Serkeley, III one public elemen. the educationalJv dl.advantaged reservations: Joseph A. Lochte Tarbell Electronics, 950 Dovlen program for the PET computer casseue or $59.95 on diskette. Disc Driv. Timing Progrtm, For $6. per issue, foreign orders tary schOOl end two private elementary school fludent, uling J r., 2 136 Pine Valley Dr., Tom, Place, Suite B, Carson, CA 90746, has lull graphics capability lor Or. D.I,V's Software, 425 Grove TRS-SO and Apple II. Keep track add $2. ComputerMat, Sox 1664, schools in the Sen Francisco Sav Apples. Send any information or onium, MD 21093. (213) 53S·4251. Hounon Instrument's HIPLOT Ave" Berrien Sprints MI 49103, of disc drive motor sPHd on e Lake Havasu, AZ 86403, (602) Aree, at IBM Research, and at a idelilS vou have to share; you plOttff, Programs in SASIC are (616)471-5514 . routine basis. Works on env disc S55-3357. futuristic home in Hillsborough , PERCOM Plug· ln Adaptar. This available for PET. TRS-SO and drive. Cassette or diskette, $14.95 may have CAl progrems relul. OunDraCon. The science-fiction, California. The participents ,n the ting from th e project. Barry fantasv, and role-playIng geme adapter is for TRS·SO and SWTP APPLE II. drive the plOller MICROSKETCH II. The first of e end $19.95. DISCO-TECH, P.O. New Softwart Publication 80 show all advocete computer Cole, c/o Sacramento City Uni_ convention is back 8{jIIin for the MP·F mini·flopPV disk controllers through a RS·232 interface. series 01 top quality programs for Box 11129. Santa Ro.a. CA Sofrware Crlriqu, i. a collection education, but theV come to the fied School District, Box 2271, fifth year, bigger and better than for data separation function and Ploller retails for $ 1085, the the TRS·80, Level II or Disk 95406. 01 rtlv,ewl of TRS-SO cessetll sub;ect Irom a variety 01 per Sacramento, CA 95810. ever! It will be et the Villa Hotel mucing data read errors. Called programs are $50 and $75. BASIC, The Main System includes SOftware. The reviews are deteiled IP8Ctivtls. Art Luehrmann of Memory requirement is 16K 49 commends and cen create en in San Mateo, 4000 EI Camino on Ihe separulor, easy to innall end Mathemuies in BASIC Sari... The end reprasent many hours of tIC. Lawrence Hall; end Dean Srown, bytl$. WEST COAST CON, Laarninll Program•. 21 progrems the 16th, 17th erld ISth of use. $29.95. Percom Date Co., infinite variety of graphics. progrem tapes solve verious math lual use. Program$ reviewed in en aducltor and conSUltant; SULTANTS, 1775 Lincoln for Apple II for elementery end February 1980. DunDraCon V, 211 N. Kirby, Garland, Teileu Includes five subsystems. Only emetical OPeretions. Thay are clude games, simUlations, aduca. Ramon Zamora of People's junior high level, including com. 386 Alcatraz, Oakland, CA 75042, (21 4) 272-3421. Slvd, Tracy, CA. 95376, (209) Sl.95. International Data Serv pr&etical working aids for profes tional programs, music programl Compulllr Company; M.ry ices, 340 West 55th St., New PUtar literacy, language am, 9461S. 835·1780. sionals and applied learninll tools and others. One yeer is $24, Laycock and Pit T ubbs, educa math, time·telling end games. York, N.Y. 10019, (212) 757- for educators. Hayden Sook lingle copy $7. 80 Sofrwal1l tors; and parenll and kids. Vi,ual, verbal end auditory rein SUPER DAZZLER. Super Daz· 8046. Companv, Inc., 50 Essex Street, Critique, p.O. Box 134, Waukegan, Montlrly Bey UIII.. Group. zler Interface is a high·resolu· Rochelle Park, New Jerwy 07662, forcements. $15.75 to $19.50. IL 600S5. IMBUG) lor the TAS·ao. We The technical consultant for this t;on graphics IOterface lor Cro Dungeon Explor. r, This game, by Timeshared Opar.ting SystltlTl. (2011843-0550. Edullk Corp., P.O. SOile 11354, meet on the IliISt Friday of every production il Bob Albrecht lalso Pelo Alto, CA 94306. memco computt!r svuems. Matthew D. Kiriazis, is an adven· For the 8OS0 and Z80 series 01 Comput.r Coin Gam... Sy Joe month at the Naval POllg.aduate of PCCI, an author and lecturer. Displays color or black·and-white ture geme for the TRS,SO. It is micros, called Chaos II. Features Super-Compil.r. For the 6502. Weisbecker, a "ew instructional School in Monterey. Our group who wal described in Time Soitswep. A project 01 the hes es varied interasts as thara ere images with UP to 756 by 484 e single player game full of multiprogramming capability, called XPLO. A structured len book which em~loys games, illus. (Fabruary 20, 1975) af /)ejng "a Oregon Council of Computer point reiolution. Super Dazzler is fentanic combat and adventure. severa! programming (anguagM, guage. Run programs 2.5 to 16 tration. and clever copy to teach uses for the TRS·ao. The Mon. pioneer in eleCtronic edUCation." Educators, seeks to lIublllh 5595, 16K two· port memory based upon Dungeons and Drl9- complete 'lile/directory system, times fMlllr. Versions for 201< readers of all ages about com. terey Bey Users Group. P.O. SOile "Don't Bother Ma, I'm learning" groups of users of same squlp. card $795. Cromemco. Inc" 280 ons. Available for sa.SO. Software etc. Objact code disk $300, Apple II, KIM, TIM and SYM puters. A supplement to other 1242, Seaside, CA 93955. Wll$ produced bV David Shep.rd_ ment who wish to share educa· Sernardo Avenue. Mounta," Exchange, 26S1 Peterboro, W. Source listings $500. Computer SYS lllms ere availeble lor under teaching material1. $3.95 soft. Ion and directed bv Keren Cerl tlonel program1. Contact: Fred Cr8lClnt City Computer Club. View, CA 94043. (415) 964- Sioomfieid. MI 4 8033. Systems Design Group, 3632 $70. Send lor free cetelog. The bound. 96 Pages. Published bv Ion. The eileecutive producer is 6502 Program Exchange, 2920 Seisse, the Real Oregon Corn Holds Friday meetings at 8 pm in 7400. Governor Dr., San Diego, CA Creetive Computing Pre$s, P.O. Steve Michelson. Mejor funding pUllr Companv, 207 Wen 10th Room 2120, UNO Science Bldg., 92122. Moana, Reno, NV 89509. Box 789_M, Morristown, N.J. lor this PBS bro.edclilSt has been P.O. Sox 1097, University of New Ave., Eugene, OR 97401. 07960. provided bV the Bell & Ho_1I Orlaans, LA 70122. 62 RECREATI ONAL COMPUTING Corporation.