Ok, so a 7800 RAM cart should work fine with 2K and 4K 2600 games.
What about everything else?
It seems like you should be able to write a preprocessor that reads in
a binary for a bankswitched 2600 game and produces a new binary which
will run on a 7800 ram cart.
The preprocessor would follow the thread of control through the 2600
binary, remapping banks to different areas of RAM, and replacing things
like "$F000: LDA $1FF9" with "JMP $E003" and such. Superchip and
RamPlus could be handled with a similar sort of remapping.
Bugaboos may occur in things like timing (LDA in the example above
is 4 cycles, JMP is only 3) and indirect and computed jumps (where the
PC is set or incremented in a way not obvious by simply examining the
binary).
Hopefully areas doing lots of bank switching won't be time critical.
For some bank switching schemes (FE) this preprocessor would be incredibly
simple.
Thoughts?
--
adam@xxxxxxxxxxxxxxxx http://cuddlepuddle.org/~adam/pgp.html
Will code for food. http://cuddlepuddle.org/~adam/resume.html
"Fools despise wisdom and instruction." Proverbs 1:7
----------------------------------------------------------------------------------------------
Archives (includes files) at http://www.biglist.com/lists/stella/archives/
Unsub & more at http://www.biglist.com/lists/stella/
