Mapping the Atari

INTRODUCTION by Bill Wilkinson

When I was asked by the editors at COMPUTE! to write this introduction, I was at first a little hesitant. How does one introduce what is essentially a map of the significant locations on the Atari other than by saying "This is a map of..."?

And, yet, there is something about this book which makes it more than "simply a map." After all, if this were "simply" a memory map, I might "simply" use it to learn that "SSKCTL" is the "serial port control" and that it is at location $232. But what does that mean? Why would I want to control the serial port? How would I control it?

The value of this book, then, lies not so much in the map itself as it does in the explanations of the various functions and controls and the implications thereof. Even though I consider myself reasonably
familiar with the Atari (and its ROM-based operating system), I expect to use this book often.

Until now, if I needed to use an exotic location somewhere in the hardware registers, I would have to first locate the proper listing, then find the right routine within the listing, figure out why and how the routine was accessing the given register, and finally try to make sure that there were no other routines that also accessed this same register.

Whew! Now, I will open this book, turn to the right page, find out what I need to know, and start programming.

Okay. So much for this introduction. And if you are comfortable programming your "home" language, the language you know best, and two or three other languages, you don't need any more from me.
So good luck and bon voyage.

Kindly donated by Geoff Lambert