Damaged cartridge repair.

[Chris]

I have an old Pokemon Blue game cartridge that developed problems a while back rendering it unplayable. I was able to copy my save file off of it and the save file was not corrupted so I know the SRAM chip in the cartridge is working fine though I cannot identify which of the 4 chips is the SRAM. Given that the SRAM is working correctly that leaves either the Memory Bank Controller or ROM chip itself as being the source of the problem and I was curious to see if perhapse there was a way to determine which one it is by examining the dump of the cartridge ROM.

If the MBC is damaged I can salvage a replacement from another cartridge. If the ROM chip is damaged I can salvage the SRAM and MBCor maybe even use the cartridge as my own dev cart by wiring in a removable EEPROM chip. Seems like a win/win either way. But how would I go about determining which chip is fried? I am leaning towards the ROM chip myself as the MBC was still used to access theSRAM and the problem did nit affect the SRAM.

The game does start and load correctly, but the moment you attempt to open any dialogue box or get into a fight it glitches up. Pokemon encounters begin to play odd noises and text becomes scrambled sprite tiles. If I could repair the cartridge I would like to. Anyone got any advice?

[Wannado]

Did you try using a blank save file instead? (Don't forget to keep a backup of your original save file, though.)
I am not a Pokemon player, but from what I heard, save files causing/saving glitches are nothing new in the Pokemon world (see MISSINGNO).

Also, does the emulator say anything about the ROM checksum? Does it display things like good dump/bad dump/overdump...?

Regarding the chips: The PCB usually indicates where each part should be placed. The ROM chip is often referred to as "PRG". See this photo on Wikipedia: http://en.wikipedia.org/wiki/File:PokemonSilverBoard.jpg

I saw several photos where the MBC had "MBC" printed on it. There seem to be different types of MBCs, so you'd have to find a matching one.
You might try searching the web for the product codes printed on the chips.