Repairing a bad rom dump

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werewolfslayr925
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Repairing a bad rom dump

Post by werewolfslayr925 »

I have a copy of Fire Emblem Gaiden that is being stubborn. The Kazzo dumper dumps the CHR just fine, but, according to BootGod's Database, the CR32 number for the PRG is always off. Once the number was especially close to correct, and the ROM loads properly in FCEUX and Nestopia; however, once you press start to get past the title screen, the game freezes. Is there a way to repair the ROM so that it's completely playable?
lidnariq
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Re: Repairing a bad rom dump

Post by lidnariq »

Can you compare your PRG dump to a known good dump from the internet and qualify how the two dumps differ? It might be easier to figure out how to fix the Kazoo script if we know where things are going wrong.
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tokumaru
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Re: Repairing a bad rom dump

Post by tokumaru »

werewolfslayr925 wrote:Once the number was especially close to correct
I don't think that similar hash numbers necessarily mean that the hashed data is similar... By design, this is not how hashing algorithms work.
Is there a way to repair the ROM so that it's completely playable?
Like lidnariq said, the only way to know exactly what's wrong is to compare your data against a known good dump.
werewolfslayr925
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Re: Repairing a bad rom dump

Post by werewolfslayr925 »

Okay, that's news to me. What's the method for comparing what I have to a good dump?
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dougeff
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Re: Repairing a bad rom dump

Post by dougeff »

There's a hex editor called windhex that can do a byte by byte comparison, and tell you which bytes are different.

http://www.romhacking.net/utilities/291/

Edit, or was it HxD ?
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thefox
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Re: Repairing a bad rom dump

Post by thefox »

HxD can do it.

On Windows command line you can do fc /b file1.nes file2.nes.
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werewolfslayr925
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Re: Repairing a bad rom dump

Post by werewolfslayr925 »

I'll see what I can do as far as comparing it to a good copy of the game and post here when I find out something new. Thanks for the tips.
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