Question regarding GBA initialization
Posted: Thu Sep 04, 2014 2:32 am
Hello!
I'm relatively new to the homebrew scene, I've lately been coding a GBA emulator as a learning exercise and am using devKitARM as the compiler for my test programs, now, what i wanted to ask was regarding the initialization routine of the GBA hardware. As shown in this file: http://sourceforge.net/p/devkitpro/buil ... crt0.s#l71 the memory is cleared based on a condition and then copied from ROM, this is done by a loop of STMIA and LDMIA in Thumb mode. I've read that the GBA provides DMA hardware that can transfer data from memory locations at least twice as fast as the CPU can, is there any particular reason why it isn't being used here?
I'm sorry if the question sounds too dumb but I'm kind of new to all this.
Thanks!
I'm relatively new to the homebrew scene, I've lately been coding a GBA emulator as a learning exercise and am using devKitARM as the compiler for my test programs, now, what i wanted to ask was regarding the initialization routine of the GBA hardware. As shown in this file: http://sourceforge.net/p/devkitpro/buil ... crt0.s#l71 the memory is cleared based on a condition and then copied from ROM, this is done by a loop of STMIA and LDMIA in Thumb mode. I've read that the GBA provides DMA hardware that can transfer data from memory locations at least twice as fast as the CPU can, is there any particular reason why it isn't being used here?
I'm sorry if the question sounds too dumb but I'm kind of new to all this.
Thanks!