super Mario bros 2j repro issue

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super Mario bros 2j repro issue
by on (#117444)
Just made myself a copy of Mario Unlimited for my first repro, and it works great. I am having a heck of a time with SMB2j though. My donor is Image Fight(Tsrom-07) I am using loopys mmc3 hack. I wired up the 27c010 for the CHR according to the NES EPROM conversion thread on here. I used a 27c512 for the PRG with no rewiring. Do I need to use a 32 pin EPROM for the PRG? I did this exact same thing to SMB3 and same result........solid pink screen : - (. I thought for sure that 27c512 chips were pin compatible with mask roms. Any help would be greatly appreciated.
Re: super Mario bros 2j repro issue
by on (#117445)
64KB and less are pin-compat. IF uses a 128KB ROM, so it has a NON STANDARD PINOUT. PINS MEAN NOTHING in this case because the ROM pins were edited for 128KB mask ROMS to save pins. Take a Mask ROM 128KB EPROM and a 27C512 EPROM pinout sheet and switch any pins that don't match. Cut the trace, wire it to the right place on the board, mapper, cart edge, etc.
Re: super Mario bros 2j repro issue
by on (#117454)
Or use these EPROM compatible boards. http://www.infiniteneslives.com/aux4.php
Re: super Mario bros 2j repro issue
by on (#117518)
3gengames wrote:
64KB and less are pin-compat. IF uses a 128KB ROM, so it has a NON STANDARD PINOUT. PINS MEAN NOTHING in this case because the ROM pins were edited for 128KB mask ROMS to save pins. Take a Mask ROM 128KB EPROM and a 27C512 EPROM pinout sheet and switch any pins that don't match. Cut the trace, wire it to the right place on the board, mapper, cart edge, etc.


Thanks, I just decided to use a 27c010 instead, seemed like less effort.
Question: Both SMB3 and Image Fight use the Ts-rom board , mario uses a 128 KB 32 pin for the PRG, and Image fight ,a 64KB (or less) 28 pin. So is the board configured differently for the 2 games? So since this board has the option to use a 28 pin or 32 pin chip, wouldnt a 27c512 be pin compatable? Or were the boards set up differently for the 2 games?