GameCube Game Saves with Dolphin/Nintendont

Discussion in 'Technical Discussion' started by Sky The Destroyer, Apr 9, 2017.

  1. So a while ago I decided to backup my GameCube saves by using GCMM on my Wii...all went well with that process. No issues. It backed up all my game saves, so I plugged them into Nintendont and Dolphin, and I tested various games with it. Results?

    I tested SADX. Works like a charm. Paper Mario: Thousand Year Door? Yup, it's all there.

    Then I come to Sonic Riders. I have two save files: 1 and 2. For some reason, save file 1 shows up as corrupted. Save file 2 works fine, though...so I plop in my Sonic Riders disc into my Wii and tested out save file 1. It's there and works perfectly fine on real hardware. Maybe GCMM ripped it wrong the first time? I try to rip it again, still no dice. I tried the RAW and GCI formats, neither makes save file 1 work in either Nintendont and Dolphin. But with real hardware it's fine.

    Same story with SA2B: I have 11 save files but yet only file 6 works in Dolphin.

    Any idea on why this happens and/or if there's a way to fix this? I'd really appreciate it; especially with the Sonic Riders save.

    Here's the save files:
    https://drive.google...QWpQdTZ5Ql9NM2s

    Thanks in advance.
     
  2. GerbilSoft

    GerbilSoft

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    I've done a bunch of stuff with GCN save files (I wrote the GCN MemCard Recover tool), so I'll take a look at this sometime tomorrow and see if there's anything obviously wrong with the save files.

    The save file working on HW but not emulation seems odd, especially if it happens with both a RAW dump and individual files.
     
  3. Any progress on looking into this? No worries if you've been busy.
     
  4. So I found this page and uploaded one of the GCI save files from Sonic Adventure 2 Battle that won't work in Dolphin for information about it: https://mm.reimuhakurei.net/?page=sa2save

    And it shows this on save file #4 (and the rest of them, though different checksum mismatch values):

    Checksum mismatch: calculated 0xf507, found 0xf4e3

    I tested save file #6 (the only one that works) and it says the checksum is correct.

    Any ideas?
     
  5. MainMemory

    MainMemory

    Have no fear...Amy Rose is here! Tech Member
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    Sounds like the save got corrupted somehow. You could try hex editing the checksum (32-bit big endian integer at 0x2880) to the "calculated" value, if that's all that's wrong with the save.
     
  6. That worked! Thank you.

    My Sonic Riders save file 1 suffers a corruption issue as well. Any way to fix that one too?

    Apparently Dolphin has a "fix checksum" option in the memory card manager, but it doesn't seem to work... (tested all of my SA2B corrupted saves with "fix checksum", and it doesn't seem to work. Had to use your manual fix for it to work. Tried it on the Riders save and it doesn't work on that either.)
     
  7. MainMemory

    MainMemory

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    There might be a standardized checksum used in the memory card, but the checksum in SA2(B) save files is unique to the game, so Dolphin wouldn't know about it. Riders likely also uses a unique checksum, and unfortunately I have no experience with those save files.