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Underdumped (possibly)
 
Reference: 1825
Closed (accepted) by: relax.
omonim2007 » 2025-01-04 20:45:33

Possibly underdumped (real ROM size 16 Mbit) because there is only one ROM chip on PCB.
Psychofox11 » 2025-01-10 16:43:20

I should be checking this one out very soon, I'll update DOM with notes about what it really is, as needed!
Psychofox11 » 2025-01-25 01:52:02

I have dumped it now and can confirm that a 2MB dump does appear to show the last 512kb of the chip as a copy of the last 512kb of the known trimmed version. My best guess is that it was prepared for 2 chips, as the checksum only passes when trimmed (which a console doesn't care about). I guess they needed to fill the last 512kb and just doubled what would have gone on the second chip.

I also confirmed that a 4MB overdump doubles the 2MB dump exactly, further showing it is 2MB. And of course a single chip would not hold 1.5MB.

I'll get this corrected within a couple days if not sooner, need to do PCB scans etc.
Psychofox11 » 2025-01-25 01:53:04

The header does specify it as 16mbit as well, however it has a checksum for only the first 1.5MB.
Psychofox11 » 2025-01-29 22:44:25

This is corrected now!
Feel free to review and close this ticket unless you have any questions for me about it!