Since I foresee having lots of questions related to CP/M on the Adam, I figured I might as well create a bucket topic for them. Who knows, it might even be useful for others!
So my first question is: how does one access the VDP (video display processor) from CP/M in assembly? On the TI 99/4A, which uses a similar VDP chip (9918A), the assembler has instructions specifically designed for this purpose to set up the VDP registers and read/write data from/to the VDP RAM space which is separate from the user RAM.
At this time I'm looking to switch from graphics mode to 40 col text mode under CP/M, although of course having complete access to the VDP would be awesome!