[RobotGymnast]

Anybody happen to know a good place to learn the basics of the .GBA file format? I don't really want to reverse-engineer VBA.

 

[Squall-Leonhart]

File format?

....fail.

its just the dumped data from a GBA cartridge.

 

[RobotGymnast]

File format?

....fail.

its just the dumped data from a GBA cartridge.

*sigh* Does it have a code and data segment similar to ASM programs? Is it divided up in any way? How is it parsed and executed? It's still a file format.

 

[Squall-Leonhart]

Specifications

 

[Spacy]

Look at the section "GBA Cartridge Header"

Aside from that header, there is no unified format. The GBA BIOS jumps to the ROM and the very first instruction in the ROM is another jump to the actual start position of the game program. Graphic data and such are placed wherever the game companie's tools wanted to place them if I am not mistaken.

 

[RobotGymnast]

Thanks

 

[lostjelly]

I'm going to go ahead and bump this thread, because it's the one that came up in Google when I was searching for "GBA file format".

What I'd like to know is how the ROM is actually dumped into a GBA file. A file is a single sequence of bytes. Is a gameboy cartridge the same? Are there not multiple different areas of memory or anything?

I notice the specification link states that the GBA maps the cartridge into memory like so:

08000000-09FFFFFF   Game Pak ROM/FlashROM (max 32MB) - Wait State 0
0A000000-0BFFFFFF   Game Pak ROM/FlashROM (max 32MB) - Wait State 1
0C000000-0DFFFFFF   Game Pak ROM/FlashROM (max 32MB) - Wait State 2
0E000000-0E00FFFF   Game Pak SRAM    (max 64 KBytes) - 8bit Bus width
0E010000-0FFFFFFF   Not used

So does a .gba file just contain bytes 08000000 to 0FFFFFFF, in order?

 

[SCHUMI_4EVER]

did you check the GBA Cartridges topic in the specifications? (quick-links to all the topic starts right at the top of the page)

Oh wait, never mind, it's probably not what you're after. Erm, well since this place isn't quite so active any more, especially with knowledge coders, it might be a better idea to ask such technical questions over at GBATemp.
http://gbatemp.net/categories/nintendo-gba-discussions.32/

 

[lostjelly]

Thanks.