Hi, I have been looking over some GCD files, looking to be able to recalculate checksums after making changes.
I think I have worked out from other source code, how to calculate the end of file checksum, but some questions:

* There are no extra bytes for data blocks than defined in the descriptor, which is
usually 0xFF00 in size. Which is the data block checksum?

* I believe the end of file checksum is ten bytes prior to end of file.
What are the next nine bytes after this?

example: (CS 01 00 01 00 85 FF FF 00 00) end of gcd file.

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I have noticed that some software that makes changes can change the fifth byte from the end (0x85 in this case).

Cheers
xArtx Reviewed by xArtx on . GCD File Format Qs Hi, I have been looking over some GCD files, looking to be able to recalculate checksums after making changes. I think I have worked out from other source code, how to calculate the end of file checksum, but some questions: * There are no extra bytes for data blocks than defined in the descriptor, which is usually 0xFF00 in size. Which is the data block checksum? * I believe the end of file checksum is ten bytes prior to end of file. What are the next nine bytes after this? Rating: 5