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 Post subject: mmc1 roms and megaman2
PostPosted: Fri Feb 18, 2005 8:04 pm 
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does anybody knows what famouse games (not including megaman2) uses mmc1, or a list?

i have the following question:

megaman2 do a inc $BFE1, that corresponde to reg 1 of MMC1 not reg3 that switchs PRGROM, after that opcode there are "illegal" opcodes that follows the inc, i thought that the first thing megaman2 would do is to switch prgrom space to cpu mem, but writes reg 1 not 3!

can anyone help me?

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 Post subject:
PostPosted: Fri Feb 18, 2005 9:11 pm 
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Legend of Zelda
Zelda 2 - The Adventures of Link
Castlevania 2: Simon's Quest
Megaman 2
Blaster Master
Final Fantasy 1 (and I think 2)
Dragon Quest 4

just to name a few. Zelda 2 is one of the few that does 8k CHR swapping, so it's one to test. DQ 4 has 512K of PRG, so it's good to test to see if you're doing the 256k page selection properly.

As for your MM2 problem... I did a quick check and as far as I can tell it INCs $FFE1 ($FFE1 has the high bit set when read... so INC $FFE1 basically does the reset write to the mapper). Afterwards the first write it does to the Reg 1 range ($A000-$BFFF) is done with a STA -- not an INC.

Are you swapping in the first 16k on startup? First 16k of PRG goes at $8000 and last 16k of PRG goes at $C000 on startup. If you're not doing this it could be why MM2 is hitting bad opcodes. Otherwise it might be a CPU bug.


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 Post subject: thx
PostPosted: Sat Feb 19, 2005 3:24 am 
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Thanks disch.

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