Commodore 64 Programmer's Reference Guide
Anu M. Gupta
This book is Commodore's answer to the many questions of Commodore 64 owners. The manual included with the 64 can get you started, but the serious programmer will probably find much in this book of great value.
The 486-page guide is thorough in its documentation of the 64's features. It begins by covering the rules governing programming in BASIC. There are examples showing how to set up expressions and the hierarchy of mathematical operations. A section on programming techniques shows the main ways to input information into the computer, and methods for conserving memory.
The second chapter is a BASIC "dictionary," with complete information and examples of what each command does. It's an excellent reference when encountering new commands. The short tutorial on using the keyboard and screen editor should put newcomers to the 64 at ease.
The next chapter is an indepth discussion on using the screen graphics of the 64. The material includes the vital memory locations for video display, display modes, programmable characters, bit-mapping, smooth scrolling, and sprites. The guide devotes more than 50 pages of the graphics chapter to programming sprites and contains sample programs with explanations. This section alone may be worth the price of the book.
The chapter on sound also combines sample programs with explanatory text to show how the programmer can make use of the 64's sound capabilities. It deals with volume, multiple voices, waveforms, envelopes, filtering, and modulation to help you create the sounds you are after.
Machine language. These two words cause some BASIC programmers to pause and catch their breath. Chapter 5 uses a relatively simple vocabulary to introduce some aspects of machine language programming. It covers several topics, including the kernal, instruction sets, and addressing modes, to name a few. A complete memory map of the 64 is featured at the end of this chapter.
An input/output guide constitutes the last chapter, with information on output to such devices as modems and printers. It also illustrates how to make full use of the RS-232 interface, user port, serial bus, and expansion port. There is also a section on using paddles, joysticks, and light pens.
100 Pages of Reference Tables
Following the last chapter are more than 100 pages of reference tables, including BASIC abbreviations, screen display codes, ASCII codes, note values for music, pinouts of all the major chips, error messages, chip specifications, and a quick reference card. The last page is perhaps the biggest surprise of all, a full fold-out schematic diagram of the 64 for hardware enthusiasts.
Commodore has done a solid job with this book. It provides 64 users with important assistance in increasing their understanding of their computer. While the book makes no attempt to teach programming as such, it is a fine reference book.
Commodore Business Machines, Inc.
487 Devon Park Drive
Wayne, PA 19087