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Hardware > can .sav files be transferred to an actual cartridge?

#10176 - yaustar - Fri Aug 29, 2003 1:35 am

This would be useful if it could...
would save me a lot of replaying..
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#10182 - tepples - Fri Aug 29, 2003 2:47 am

To overwrite the SRAM in a Game Pak or flash cart, just wrap the .sav file in a multiboot program (with something like GBFS, that's relatively easy) and send it over the MBV2 or XBOO cable. The multiboot program should copy the bytes from RAM to the cartridge, in descending order (0xffff in .sav -> 0xffff in SRAM, 0xfffe->0xfffe, ..., 0x0001->0x0001, 0x0000->0x0000).

Why descending order? Your typical .sav file is 64 KB, but real SRAM is often 32 KB or smaller, and if you copy in forward order, you may overwrite bytes that you had written previously.
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#10185 - yaustar - Fri Aug 29, 2003 5:00 am

tepples wrote:
To overwrite the SRAM in a Game Pak or flash cart, just wrap the .sav file in a multiboot program (with something like GBFS, that's relatively easy)


what is GBFS?

would it work if I used the EZFA linker program?
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#10197 - torne - Fri Aug 29, 2003 11:52 am

If the real game cart uses SRAM, then any flash linker should be able to write to the real cart just the same way as to a flashcart. If the cart uses EEPROM or Flash, then bets are off (I don't know which linkers, if any, can do that).

#10220 - yaustar - Sat Aug 30, 2003 2:17 am

cheers
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