Different ROM revisions? [dumping related]

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Different ROM revisions? [dumping related]
by on (#184123)
I started to dump my own cartridges. Some are OK, but others have different CRC32 (yeah, I've cleaned up the connectors with alcohol and cotton swabs, and did the dumping twice or 3x... or even more).

For example, I was expecting my Mega Man IV dump to have a CRC32 of $18A2E74F, but I got $2bc67aa8. Gameplay and graphics are perfectly fine, no glitches. Another example is Gradius II, a pirate cart where you can select weapons with B+Select. Tried a lot of times, the same result. The game works, but the graphics are all corrupted. I can't open the cartridge case - I glued it 20 years ago, no way to deglue it... unless I break the case. No, I won't. ^_^;;

For Gradius II, these are the CRCs:
Code:
Gradius II.nes, mapper 25
Program ROM: size 0x020000, crc32 0xfdc83487
Charcter ROM: size 0x020000, crc32 0x116d5e18


- There's a Super Mario Bros. 3 cart sold in Brazil by Playtronic. Yup, original, but with a different PRG ROM CRC32.

- I have two other carts unable to get a correct dump. A 2in1 yellow cart within Side Pocket (?) + Rockman 1. The loaded game varies with RESET. The other cart is the 600in1 (only 33 unique games on it).
Re: Different ROM revisions? [dumping related]
by on (#184125)
Zepper wrote:
For example, I was expecting my Mega Man IV dump to have a CRC32 of $18A2E74F, but I got $2bc67aa8.
http://bootgod.dyndns.org:7777/profile.php?id=804
(There were multiple revisions)

You can search NesCartDB by CRC, which might help.
Re: Different ROM revisions? [dumping related]
by on (#184127)
Megaman 4:
First version: 2BC67AA8
Revision A: 18A2E74F
Re: Different ROM revisions? [dumping related]
by on (#184128)
Here's another different cartridge, Super Sprint. It was sold here in Brazil by Gradiente.
Code:
Super Sprint.nes, mapper 4
Program ROM: size 0x010000, crc32 0x314790c9
Charcter ROM: size 0x040000, crc32 0x2adba329
Re: Different ROM revisions? [dumping related]
by on (#184131)
Any unusual copyright text?
Re: Different ROM revisions? [dumping related]
by on (#184133)
Zepper wrote:
Super Sprint.nes, mapper 4
Program ROM: size 0x010000, crc32 0x314790c9
Charcter ROM: size 0x040000, crc32 0x2adba329

http://bootgod.dyndns.org:7777/profile.php?id=716
Are you sure that CHR is 256 KiB in size?
Re: Different ROM revisions? [dumping related]
by on (#184179)
Nope. Also, I dunno it's mapper 4. It simply worked after the dump.