Rahsennor wrote:
There are NSFs out there that depend on copy semantics for FDS RAM? Argh.
I identified and posted corrected rips of all the ones I could find earlier in this thread, but yeah unfortunately the old versions are still
floating around out there.
Rahsennor wrote:
If the code isn't buggy it should never write to locations it believes to be ROM
FWIW buggy code is easier to identify on an NSF, since they're deterministic. A lot of stuff can be tested in an automated way.
Rahsennor wrote:
Due to a few homebrew NSFs checking for write-protect and refusing to play without it (I'm looking at you w7n) I hacked it to treat $8000 as a port.
Ha! That's interesting.
I would just say that multi-chip just implies write protect for FDS at $8000-$DFFF. I don't think it needs to be more complicated than that. The only common hardware implementation I know of for this is the TNS-HFC series of cartridges, and they bypass the FDS RAM just using the normal NSF setup (RAM at $6000, ROM at $8000+).
Without multi-chip there's really never any reason to write protect the FDS RAM, since there's no conflict necessitates writes to it. (Very easy to test and make sure it doesn't write by accident due to the determinism, too.)