[SOLVED] Emulating Mapper 225 (64-in-1 rom) question.

Hi guys,

I've almost completed this mapper and I'm testing it with the "64-in-1" ROM, but I've run into some strange problem:

Every game in the list works except for B-Wings. This game alone is mapper 185, which I currently support right now and I've got it running just fine.

When running B-Wings from the 64 in 1 cart menu, I just get a blue screen (as if the copy protection mechanism wasn't emulated correctly, and the game was locked). As far as I know, the games on this multi cart are hacked to be NROM / CNROM compatible, so nothing special seems to be necessary to emulate it correctly.

Could it be something I'm missing?

Thanks again for your help in advance.

Hey guys,

Nevermind. We found out we were handling writes to PPU $0000-$1FFF region in a wrong way. Writes were not inhibited when not CHR RAM (CHR ROM was being corrupted and strange things were happening), and it turns out that B-Wings makes some writes to that region.

Added that check to our PPU CHR write handler and everything is working just fine.

Thanks!

Cowboy kid and Fantasy Zone 2 also have this problem.

Plus, try Ms. Pac Man - it writes to $8000-$FFFF when it shouldn't!

I tried them a little and they looked OK! Thanks Zepper!