What about this don't you understand? This is simple BASIC.
Edit: You guys DO know, I hope that I was only using BASIC to show you a simple way of doing this. It can be accomplished using Assembly more easily. Any language, actually. I was only providing a template.to help new users who haven't read the manual, available here: http://sdx.atari8.in..._User_Guide.pdf
(Banging my head off the wall now, if you guys can't figure it out yet.)......