Re: [midatlanticretro] Basic Compiler for Atari 2600.
Mr Ian Primus wrote:
--- On Thu, 2/26/09, Ray Sills <raysills@...> wrote:
Wow. Only 128 Bytes of RAM?? They must have used some sort of video generator chip that could store and move images.
Hehe. No. The Atari can't do that. The playfield must be drawn one scanline at a time. There is a TIA register that holds 20 bits of data. This controls half the playfield. It's automagically mirrored on the other half. If you want the playfield to change and not be vertical lines, you must change the register in the retrace time between the scan lines.
Like I mentioned in the previous post, there's loads of programming info, tutorial and various software tools , at the link below to learn all about this. It's a very good website--give it a read.