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Last updated on Oct-18-2019 Download

Anyone think this mapper conversion is possible?

Anyone think this mapper conversion is possible?
by on (#65886)
I'm looking at converting Vs. Dr. Mario (MMC1) to use a VRC1 or "VRC1 like" instead. I've looked at Vs. Dr. Mario and the banking code seems pretty easy to follow. I think, I don't know for sure, that the the PRG code probably has $C000 fixed which from my understanding from the wiki makes it easier to convert. The CHR part I'm not as sure about. The graphics stuff never seems to get through to me.

by on (#65890)
It's surprising that VS Dr. Mario has PRG banking, since the original game didn't need it.

by on (#65918)
The Vs. Games are a bit different then the Nes games. I'd say almost all of them have double the PRG size. I'm fairly certain that there it is banking the PRG, but only because of the EPROM size used.

by on (#65924)
Converting The Legend of Zelda from MMC1 to FME7 was pretty straightforward. I ended up having to duplicate some tiles in order to get the chr-ram to chr-rom conversion to work. I don't know off the top of my head what Dr. Mario uses.

by on (#65933)
never-obsolete wrote:
Converting The Legend of Zelda from MMC1 to FME7 was pretty straightforward. I ended up having to duplicate some tiles in order to get the chr-ram to chr-rom conversion to work. I don't know off the top of my head what Dr. Mario uses.


There was two prototypes for Dr. Mario, known by the name Virus for unknown reasons, those are the two revisions that still exist so far!

One has MMC1 and one has NROM, a person at NintendoAge most possibly still owns both after buying them from Ebay, they are not dumped yet. (according to Lost Levels Forums), But I do not know who.

That is a reason why it uses only a single 32k bank (or 2 16k banks) and 4 times the CHR amount the original source proto (NROM) has

by on (#65935)
never-obsolete wrote:
Converting The Legend of Zelda from MMC1 to FME7 was pretty straightforward. I ended up having to duplicate some tiles in order to get the chr-ram to chr-rom conversion to work. I don't know off the top of my head what Dr. Mario uses.


See that is the kind of stuff that doesn't sink with me. Duplicating Tiles. I don't know why it shouldn't be that hard.

by on (#65939)
Hamtaro126 wrote:
There was two prototypes for Dr. Mario, known by the name Virus for unknown reasons

I'll take an educated guess that it was called Virus because the -rus in Virus sounds like the -ris in Tetris, and because Nintendo marketing hadn't yet thought up the scheme to whore Mario in every genre Nintendo could think of.

Quote:
That is a reason why it uses only a single 32k bank (or 2 16k banks) and 4 times the CHR amount the original source proto (NROM) has

Both Tetris and Dr. Mario could probably have been done in CNROM. (In fact, Tengen's pirate-original Tetяis is CNROM.) Perhaps Nintendo had excess MMC1 inventory as more developers were switching to MMC3 for its scanline counter, fine CHR ROM bankswitching, and DPCM bankswitching.