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ASM > GBA rom disassembler?

#4660 - tomtom - Sun Apr 06, 2003 4:57 pm

Hi!
I'm looking for a GBA rom disassembler. Are there any?
I would like one that replace branch addresses with labels, so the code can be modified and re-compilated.

Maybe a simple ARM disassembler would work? Are there any freeware ones?
Thanks per advance for any info [Images not permitted - Click here to view it]

#4672 - peebrain - Sun Apr 06, 2003 7:56 pm

Mappy?

~Sean
_________________
http://www.pbwhere.com

#4681 - torne - Sun Apr 06, 2003 11:48 pm

objdump, from binutils (with devkitadvance) can do it; the problem is that roms do not indicate which portions of their contents are code. You will need to find the section boundaries yourself.

If you are working with homebrew stuff, then use objdump on the elf binary instead as this still has section info. If you're working on .bin/.gba roms only, try experimenting with objdump and various, but ultimately you will find it very difficult to break down and reassemble the rom due to the lack of section info. What seems like a trivial change might, for example, break the alignment of data elsewhere in the file, and the assembler cannot fix this for you because the alignment data, section headers..etc were all discarded when the ELF binary was converted to a rom image.

You can use mappy..etc to change small portions of code in a rom, though, I think; but disassembling and reassembling the whole thing is, unfortunately, out of the question.

Torne