Book Review

TRS-80 Color Computer BASIC

Tony Roberts, Assistant Managing Editor

If you have a Color Computer and are taking your first steps in BASIC, Richard Haskell's book, TRS-80 Extended Color BASIC, can help make sure your feet are firmly planted.

Like its companions for the Apple, Atari, and PET computers, this book is designed as a textbook. It starts out assuming the reader knows nothing about the TRS-80 Color Computer (or BASIC) and builds from there.

Although the title implies that the contents refer only to Extended Color BASIC, the book serves equally well as a Color BASIC tutorial. Only a few, short references are made to commands or functions not available in Color BASIC.

Though written to be used with a computer at hand, TRS-80 Extended Color BASIC can be a useful study guide when no computer is available. The 170-page book is packed with screen photos that show what happens when the sample programs are run. The photos also show what happens when common programming or input errors are made. The text carefully explains why the mistakes happened and shows the novice programmer how to avoid the problem in the future.

Start With The Basics

Once you have been introduced to the TRS-80 Color Computer and have learned to print your name on the screen, TRS-80 Extended Color BASIC takes on the BASIC statements one by one.

Many of the example programs in the book's early chapters have a mathematical bent. You learn to compute the area of various geometric shapes, and you are treated to an explanation of the trigonometric functions. Some of these may be lost on the beginner who is more concerned with learning about the computer than recalling high school math.

Once those problems are out of the way, however, Haskell clearly explains the things beginners need to know to get started in programming — printing to the screen, loops, and the IF ... THEN, ELSE statements. Further along the way, simple and high-resolution graphics, sound, arrays, and the PEEK and POKE statements are covered.

The final chapter, called "Putting It All Together," leads you step-by-step through the programming necessary to create a hangman game and to turn your computer into a color organ.

No Machine Language

Though the book makes no attempt to teach any machine language, one of the nine appendices discusses, in a few short paragraphs, how to use a machine language subroutine in a BASIC program. Other appendices include information on BASIC'S reserved words, ASCII codes, error messages, hexadecimal numbers, the EDIT statement, the PRINT USING statement, and screen locations.

TRS-80 Extended Color BASIC allows beginning programmers to build their knowledge of BASIC in a logical, understandable way. By following the examples and studying the dozens of illustrations provided, it should be a quick transition from taking your first steps to running your own BASIC programs.

TRS-80 Extended Color BASIC
Prentice-Hall, Inc.
Englewood Cliffs, NJ 07632
$12.95 paper, $19.95 cloth