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DS development > Accessing GBA Cart ROM from the ARM9?

#42768 - Abcd1234 - Sat May 14, 2005 9:04 pm

Mayhap I'm just doing something wrong, but in some code I'm working on,I'm attempting to read from the GBA cart rom from the ARM9, and all I'm getting back are zeros. Stupid question, but: can only the ARM7 access the cart ROM? Or is there something I need to do to grant the ARM9 access to it?

#42777 - josath - Sat May 14, 2005 10:54 pm

according to this:
http://www.bottledlight.com/ds/index.php/System/WaitStates
Quote:
ARM9 can access GBA slot by clearing bits 8080 of WAIT_CR

If i understand correctly, then you just need to do:
Code:
WAIT_CR &= ~(0x8080);

#42779 - Abcd1234 - Sat May 14, 2005 11:28 pm

Awesome, I knew it was something like that... just didn't know where to look. :) Worked like a charm, thanks!