• 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.