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+--- Thread: ID of cart based on size (/showthread.php?tid=5495)
ID of cart based on size - KanedaFr - 07-14-2025
Analysis based on method found at ff30f8 (so 0x30F8 in BIOS)
This was probably already shared but something bugged me so I looked at it myself.
=> Does the manufucter code is related to size or any size could be used with any manufacturer ?
Please correct me!!!
To read info about current ROM, BIOS first enable CFI
write 0xAA at 0x??5555
write 0x55 at 0x??2AAA
write 0x90 at 0x??5555
First read a 0x??0000 is manufacture code
- 0x98 -> Toshiba
- 0xEC -> Samsung
- 0xB0 -> Sharp
Read custom Id at 0x??0003
- byte should a value between 0x80 to 0x87
Read size at 0x??0001
- 0xAB -> 512K -> 10th block reserved for system (see BIOS 0x2EC0)
- 0x2C -> 1M -> 18th
- 0X2F -> 2M -> 34th
Read custom id at 0x??0002
- at 0x200000+ (lo ROM), this value should be the same for EACH block, else game will reset
- at 0x800000+ (hi ROM), if it's 1, it seems to enable developer mode, with auto watchdog clear, etc.... (see BIOS 0x1DC0)
Based on this, it seems there is no link between manufacturerID and sizeID
RE: ID of cart based on size - sodthor - 07-14-2025
you re going very low level, maybe Flavor can answer that as he designed the flash masta.
Never gone so far on my side.
RE: ID of cart based on size - KanedaFr - 07-15-2025
based on https://github.com/TheFlav/Flash-Masta-Desktop/blob/993e4ef0bf0a81c95da293019019a2ce02438b42/src/cartridge/ngp_cartridge.cpp#L1634, it seems it"s not handled per game on FlashMata