30 Apr
2005
30 Apr
'05
2:37 p.m.
Tony Duell wrote:
I've never seen an electronic copy of any of the Techrefs, I am not sure
if IBM would explode if somebody started distributing them, either.
There was no separate TechRef for the CGA card.
The hardware is covered
in the normal Options and Adapters Techref.
...which I don't have :) Oh well, hopefully there's electronic copy somewhere.
It's supported by the
standard mainboard BIOS, the source lising of which is in the
machine-specific techrefs.
I don't have that either, but I've disassembled my own BIOS and found that it
is nearly useless to me -- for example, there are instructions that take longer
to execute out of RAM (4 cycles per byte opcode) than ROM (2 cycles) -- so it's