Basic Sega Genesis/Mega Drive hacking problem

Started by BigDaddyAEL1964, March 28, 2016, 08:16:12 PM

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Hello community,

I'm totally new on ROM hacking and I decided to give it a try by editing some text on a Sega Genesis ROM.

I downloaded WindHex, I loaded a FIFA International Soccer in it, and I messed up the word "Exhibition", writing "Exhibotion" just to see what happens.
I "Save As" the ROM, I load it on Kega Fusion emulator and there comes the "Incorrect Checksum" message.

So, I download ESE Fix Checksum, I load the hacked ROM, I fix the checksum.
I load it on Fusion again, there is no "Incorrect Checksum" or anything, but the game just doesn't start. Only a black screen.

I decide not to mess with checksum, and see what happens. I change the word "Exhibition" to "Fxgibition", so for the total value to remain unchanged.
I load it on Fusion once more, the game won't start.

I try to work on a different ROM, nothing happens; if I change anything, the game won't start. If I edit the very same ROM writing the word to it's original form again (e.g. Exhibition), the game starts normally.

So, what am I missing? What else should I change to make the game run normally with the text changed?


I just tried editing text on "Twin Cobra". I was able to change stuff and still get the game to start. With FIFA I was not. Perhaps the game has some kind of modification protection?


Yes, you 're right! I tried it, it worked for me too!
The problem must have something to to with EA games, as the other ROM I tried instead of FIFA was College Football USA '96, which is produced by EA too.

So guys, the question has to change: anyone knows how to edit text in EA Sports Sega Genesis ROMs?!


We could go into depth for these things, however for playing around purposes have a look to see if any of the games you want to hack and have this trouble have game genie or action replay "needs to be always on"/master codes/... type codes as for the megadrive/genesis this is what they are there to solve.
In this case
Game genie
North American version
    Master code:

Add that to your emulator, or if it does not support it then hardcode it with something like CCCGP (should be able to get a version from ).
By the time you could hack your own master codes you would probably not need it explained.