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Enhancing Your Apple II (A Review)..................Bill Morgan

Don Lancaster, the well-known author of electronics books for the hobbyist (and a subscriber to AAL), has now entered the Apple arena in a big way.  His latest book, "Enhancing Your Apple II, Vol. 1", promises to be the start of a long series of easy-to-use guides to the important internal workings of the Apple.

The main enhancements he offers in this volume are simple modifications to the Apple's video circuitry, to allow EXACT software access to the video timing.  This permits your program to play all sorts of tricks with the display modes.  There is also a wealth of information on the Apple's techniques of video storage and output.

The basic hardware modification is a single wire from an IC in the video circuitry to either the cassette or the game input.  With this wire and a little bit of code, it is easy to switch display modes between screen scans, avoiding a lot of messy glitches on the screen.  With more code, and careful timing, you can lock the processor to the display timing and switch between text and graphic modes (hi-res or lo-res) in mid-line.

There is also a very good 60-page chapter on disassembling and understanding other people's programs.  Don presents a novel technique of color-coding a printout of a monitor disassembly, to bring out the structure of a program and the function of each routine.  The example program is Apple's High-Res Character Generator, from the DOS Toolkit.  He later uses the information discovered about the character generator and the Hi-Res display to develop a slower and smoother scrolling routine for Hi-Res text.

He shows us other enhancements, as well.  There are two different ways to attach a modulator's output line to your TV set, avoiding that clumsy little switch box that the manufacture gives us.  How about a programmable color-killer circuit?  With this one you can have software control of color vs. black-and-white display.  There are sections about generating extra colors, in both Hi-Res and Lo-Res graphics.

In the back of the book are postcards for sending feedback and ordering other materials.  All the code in the book (26 programs) can be ordered on diskette, for $14.95.  He uses the DOS Toolkit Assembler, but we plan to talk to him about providing the programs in S-C format.  You can also order a kit of the parts for all of the hardware modifications he describes.  That kit costs only $11.95 + shipping, from a dealer in Oklahoma.  Future plans include more volumes of enhancements and a possible bulletin board system for updates to the books.

All in all, "Enhancing Your Apple II" looks to be an important and useful book.  Like all of Lancaster's books, it is published by Howard W. Sams.  It is 232 pages long, size 8 1/2 X 11 inches, and sells for $15.95.  We have ordered a stock here at S-C, and will sell them for $15.00 + postage.

For Volume 2 of the "Enhancing" series, he has promised us more video techniques, a keyboard enhancer, something called an "Adventure Emergency Toolkit", graphics software for daisy-wheel printers, a two-dollar interface for the BSR controller, and much more.  I'm looking forward to it!

This is a good time to mention another of Don's books, which has received too little attention.  I am speaking of "The Incredible Secret Money Machine".  Despite the title, it is not a get-rich-quick pamphlet, but rather a very, very useful guide to starting and operating a free-lance technical or craft business.  "Money Machine" is 160 pages of tightly packed information on strategy and tactics, getting started, and dealing with customers, suppliers, and the government.

There is enough practical advice on communication, both verbal and graphic, to make up several courses in advertising and technical writing.  Bob and I refer to this book regularly, and have long felt that it is one of the best books around for the budding entrepeneur.  We have also ordered "Money Machine", and will sell it for $7.50 + postage.


Last minute addition:  We just received a review copy of another new book from Don Lancaster, Micro Cookbook Vol. 1 - Fundamentals.  This one is a very basic introduction to microcomputer principles.  He talks about how to learn and what to learn, and introduces some hardware fundamentals.  He also promises Vol. 2, about Machine-Language Programming.  It looks very good; I'll have more details next month.  We especially like this sentence at the end of the Preface:  This book is dedicated to the 6502.
