Few features of a home computer confuse the novice computer owner more than software. Many of these new owners have studied the system manuals, they have possibly read articles or even books on microcomputers. Many of them already pro- grammed their ATARI computer in BASIC, FORTH, PILOT or another high level language. After a while, they will find out that the language used is too slow for their needs (animation, sound, graphics, to name just a few applications). They also want to know more about the internal things happening in the computer. They are most likely aware of the ubiquitous O's and 1's that control the computer. But how do those ubiquitous digits relate to the information displayed on the screen and to the language of the computer. How can they be put to work?
The subject of this book is to teach you how to program your ATARI computer in 6502 machine language. You may use a machine language monitor (like ATMONA-1, Monkey Wrench, the Debugger from the ATARI Editor/Assemblercartridge or the built in monitor from KDOS), to enter and start the programs listed in this book. Later on we will find out that itis too cumbersom to do the assembly by hand. We than use an assembler for our programs and we will learn how to call machine language subroutines from BASIC.