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PostPosted: Thu Jul 10, 2014 1:53 pm 
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So I wanted to put the Super Mario Bros. Unlimited rom hack onto an actual cart. I saw that the original SMB cart was
NES-NROM-256
Mapper 0
32kb PRG
8kb CHR

if I use tniNES to split the original ROM into PRG and CHR files, they come out to the proper sizes, but if I split the Unlimited patched ROM, the PRG is now 128kb and the CHR is 32kb. My question now is what kind of donor cart would I need to use this hack, obviously I would need a 1mbit EPROM for the PRG and a 256kb for the CHR, but what board matches those specs that uses Mapper 0? Or is the mapper not relevant at that point? I am still very new to the repro scene so sorry if some of my logic doesn't make much sense, thanks for any assistance you can offer.


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PostPosted: Thu Jul 10, 2014 3:48 pm 
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They certainly changed the mapper, since 32KB and 8KB are the limits of PRG and CHR of NROM. Open the ROM in an emulator like FCEUX or Nintendulator that will show you some info for each loaded ROM, including the mapper.

Then you can go to the wiki and see what board name corresponds to the mapper number: http://wiki.nesdev.com/w/index.php/Cate ... ES_Mappers

Then you check this table for other games that use the board.

EDIT: A quick online search revealed that this hack uses the MMC1 (you should still check to be sure). Look here for a board that supports the PRG and CHR sizes you have so you can look for donors in the table above. Don't forget to check whether this hack uses PRG RAM as well.


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PostPosted: Fri Jul 11, 2014 9:15 am 
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Thank you, that's very helpful. Looks like I need a SJROM cart


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PostPosted: Fri Jul 11, 2014 1:05 pm 
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SJROM appears to be a little uncommon... SKROM is more common, and should work just as well. The wiki page says 128KB of CHR-ROM, but you can surely use less than that. Maybe the wiki specifies configurations that have been found in existing carts, not all possible configurations.

Anyway, boards that use the same mapper chip can often be converted into other boards if you know what you're doing. For example, you can add 8KB of WRAM to a board that doesn't originally have it, effectively converting SLROM to SKROM.


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PostPosted: Fri Jul 11, 2014 1:47 pm 
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I think the different combinations of ROM sizes use different boards because different pinouts need different routing of chip enable signals.


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PostPosted: Tue Jul 15, 2014 9:21 am 
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Ok, so I got Al Unser Jr. Turbo Racing as a donor cart, it's a NES-SKROM as suggested that uses MMC1.

http://bootgod.dyndns.org:7777/profile.php?id=383

So my question now is if I have a 1mbit EPROM for the PRG, and a 256kb EPROM for the CHR which are sized perfectly to the Mario Unlimited files and require no more pins than the donor cart already uses, can I just solder in the EPROMs as is or will I still need to do some wiring? If wiring is required, which of these pin outs should I follow?

http://nesdev.com/NES%20EPROM%20Conversions.txt

Thanks for the help so far

* edit *
I just noticed from looking at the Al Unser board that the CHR is actually the 32 pin and the PRG is only 28 pins so some wiring will definitely be required


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PostPosted: Tue Jul 15, 2014 11:47 am 
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Even if the number of pins was the same, rewiring is always necessary for memory chips larger than 64KB (512Kbits).


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PostPosted: Thu Jul 17, 2014 12:03 pm 
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Okay, so I think the CHR can be done without rewiring as it's only a 32KB file and I have a 256kbit 28 pin EPROM. My question now is does anyone know the pin out required for the PRG - 32 pin 1mbit EPROM on a SKROM MMC1 scenario? Thanks

http://bootgod.dyndns.org:7777/imagegen.php?ImageID=2664&width=600


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PostPosted: Thu Jul 17, 2014 2:11 pm 
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Location: Seattle
http://wiki.nesdev.com/w/index.php/Mask_ROM_pinout


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