New MMC3 clone or just another rebrand?

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Fisher
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New MMC3 clone or just another rebrand?

Post by Fisher »

Hello.
Recently I've got another pirate game, Robocop, wich uses as mapper an IC labeled as 9051.
Pictures of the board:
Assembled PCB:
Assembled
Assembled
Component side:
Component side
Component side
Solder side:
Solder Side
Solder Side
The IPS with the ROM differences from Robocop (J):
Robocop-Pirate.ips
(41 Bytes) Downloaded 92 times
The CHR ROM has the exact same CRC of the original japanese Robocop, so these 41 bytes are form the PRG ROM or from some error I've got while dumping.
The gamed booted fine in Nestopia with the .NES file I've build.

Unfourtunatelly I couldn't trace the board yet.
So, as the titles says, I'm asking if this is another different MMC3 clone or just a rebranded one?

Another thing that makes me curious is the place for another IC, just over the 74'32.
What could it be, another kind of CIC defeating circuit?

Hope someone can help me to figure it out.
Thanks in advance.
lidnariq
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Re: New MMC3 clone or just another rebrand?

Post by lidnariq »

I always assumed that the "9112" MMC3 clone was just a date stamp. I'd naively assume it's true this time also.

The 74'32 is almost certainly there to permit the use of a 28-pin 128KiB mask ROM.
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krzysiobal
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Re: New MMC3 clone or just another rebrand?

Post by krzysiobal »

The top (non-populated) DIP40 chips has MMC3 "88" pinout.
The populated one (9051) has "9112" pinout.
7432 is indeed used for CHR/CE (with extra delay)
other DIL14 aswell as some weird non-populated vias are still being investigated.

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