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 MMM01 games
Argument: Generic , Reference: 2805 , Closed by: root
Tauwasser @ 2013-03-28 01:58:33


just wondering how MMM01 games should be handled. Right now, all dumps for Momotarou Collection 2, Taito Variety Pack, as well as the Mani 4-in-1 packs all conform to the raw binary data and not to the mapped binary data.

Basically, the first two banks are actually the last two banks of the ROM image. However, since the ROMs are a) unplayable that way and b) have their internal checksum conform to the mapped ROM shouldn't the dat files reflect this?
BigFred @ 2013-03-29 11:14:10

At least MC2 and TVP can be played with rew right now. The others just fail due to improper header settings.

Since the mapping-process is part of proper emulation it's not a good idea to change the entries. Besides: Even if you modify the dumps they won't be playable in other emulators so there is no real point to do that atm. Technically this would also be hacking just like the NES mapper conversions. Besides it's not that we miss anything here since these games can be played otherwise easily ;)
Tauwasser @ 2013-04-02 05:45:06

Well, byuu's higan right now has very basic MMM01 support up and running. It's just that it doesn't support heuristics for finding out the image type - so it expects the real header to be first.

Also, I look at this from a dumping point of view. After reset, the MMM01 defaults to these two rom bank, so naturally, they are the first thing to be dumped in an image.

However, I do think it's problematic that the MMM01 seems to support more than two rom banks before final mapping -- as evident by bank switching code in MC2 IIRC. However, my testing has been inconclusive, because I could not get additional Rom banks to load properly. But that might have been a mistake on my part, because I could not fully test the mapping logic yet.

Should this be made into a forums discussion?