A couple bugs related to the SA-1

[imamelia]

I've been talking to an acquaintance who is working on patching the SA-1 into a game that doesn't normally use it, and he's noticed a couple bugs pop up in SNES9X. First, one bit of a certain register isn't emulated properly. I forgot which bit it was, but it makes it so you can't map 8 MB of ROM data to banks $00-$3F, $80-$BF, and $C0-$FF in that order (part of the $C0-$FF area, if I remember correctly, instead acts like a mirror of the $80-$BF area). Second, according to him, character conversion DMA only works for addresses that mirror $400000-$407FFF, not $408000-$41FFFF. He had to use a custom build of SNES9X to combat the first problem and work around the second by putting the CCDMA buffer in that first area. Will these bugs be fixed in the next version?

[Camo_Yoshi]

If you're trying to program so that the code runs on the original hardware, try bsnes instead, as it focuses on emulation accuracy rather than system compatibility.

[imamelia]

Oh, don't worry about that. I use bsnes primarily. The problem is that most people don't, and while I don't care enough about ZSNES and its myriad of emulation errors to worry about compatibility for it, SNES9X is at least decent enough that I'd kind of like stuff to work on it, unless it's something that just plain can't be done on SNES9X (without substantial increases in accuracy).

Also, clarification: according to him, $2220-$2223 are the registers in question. Bit 7 of them, I believe, is the offending one.

[OV2]

We'll definitely take a look at it.

I he's already fixed it a pull request would make it a lot faster