Creating a patch

[superruzafa]

Hi.

I'm trying to create my own patch which replaces samples in a PSX game.

I replace all samples overwriting 2048 by 2048 bytes and skip 304 bytes of ECC. The problem comes when I try to play the game, I only heard a little bit of the sample and then a scratch.

I guess is a problem of ECC checking.

Where can I found info about patching psx games? NOT TO APPLY AN ALREADY PREMADE PATCH but create my own patch and regenerate this ECC code.

Thanks.