Hacking Can't trim some GBA roms

[nl255]

I have a few roms that don't seem to want to trim. They are Riviera: the Promised Land, Sword of Mana, and the Capcom Classics Mini Mix. Has anyone been able to trim these roms or are they just untrimmable. I have noticed a repeating pattern like FF 09 00 C0 (Sword of Mana) or 00 20 10 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 20 10 00 00 00 00 (Riviera) near the end followed by some other junk FF FF FF FE, etc. Are these roms just untrimmable as they actually use all the space or is all that stuff some kind of watermarking or other removable stuff?



1267 - Sword of Mana (US).gba - CRC32: 7F1EAC75
2039 - Riviera - The Promised Land (US).gba - CRC32: 4FB6958D
2489 - Capcom Classics - Mini Mix (U)(Rising Sun).gba - CRC32: 0BB2D391

 

[how_do_i_do_that]

some come pretrimmed if you went and downloaded it somewhere.

 

[nl255]

Nope, they are the full size roms. Any idea if parts of it are safe to trim or not?

 

[Rayder]

I'm not sure how all slot2 flashcarts work, but when you patch them for the cart, they pretty much already trim them. So, unless you mean you're running them in an emu on the PC, I don't really see where trimming a GBA ROM is necessary.

 

[TheSpade]

Are you trimming these manually? If so, then you are a brave soul indeed. If not, then what trimmer are you using? I understand that NDSTokyoTrim now does GBA ROMs with excellent results. Give it a try.

 

[Mikef]

You can trim only repeating 00 or FF from the end of the file going backwards until it changes to something else, keep at least 1 byte 00 or FF at the end.

Mike

 

[DanTheManMS]

If it's like several megabytes of 00 or FF, then a few random bytes, then a few more 00 or FF bytes, chances are you can trim away those few garbage bytes and continue trimming until you get up to what is obviously actual data. Not necessarily true for all games, but it's worth a shot.