Sega Genesis/Megadrive Incorrect Checksum's

[Simombelmont]

why are so many games with Incorrect checksum?
i found various like Double Dragon and Battletoads,Slap Fight MD,Rockman Mega World and much more games did this affect the gameplay?

[Fonix]

It is a known issue with Genesis/Megadrive games:
http://www.retrode.org/documentation/co ... ames/#sega

If you look down the list, you will see some games listed with a Extra/Issues note of: "Chksum error reported, works fine" or "Chksum error(1)"
Scroll down the list to see note explinations:
(1) According to Cowering's GoodGen, the dump is true to the original.

Your best bet would be to check your crc32/sha1/md5 against dat-o-matic and if you dump something different, let us know. If you are just downloading roms off the internet and it doesn't match dat-o-matic, then it's very likely a bad/modified dump.

[Simombelmont]

It is a known issue with Genesis/Megadrive games:
http://www.retrode.org/documentation/co ... ames/#sega

If you look down the list, you will see some games listed with a Extra/Issues note of: "Chksum error reported, works fine" or "Chksum error(1)"
Scroll down the list to see note explinations:
(1) According to Cowering's GoodGen, the dump is true to the original.

Your best bet would be to check your crc32/sha1/md5 against dat-o-matic and if you dump something different, let us know. If you are just downloading roms off the internet and it doesn't match dat-o-matic, then it's very likely a bad/modified dump.

yeah but it is good or not?
why is the problem that makes the checksum errors?

[MikeHaggar]

yeah but it is good or not?
why is the problem that makes the checksum errors?

Devs didn't care since they didn't use the checksum for anything and the game worked fine anyway?

[KingMike]

Crazy that, as I recall, even Sega themselves didn't bother with correct checksums in some cases.