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DS development > Several problems about ds loader？

#64510 - swzte - Fri Dec 23, 2005 4:59 am

Using PassMe, ds can run the code(*.nds.gba) stored in flash card.But I have several questions here. First, PassMe changes the PC and make DS jump to GBA Card space, who can tell me the address the PC jump to? Is it 0x080000C0 or 0x08000000?Sencond, the loader runs in DS mode or GBA mode?Third, as we all know, ds has two cpus, arm7 and arm9, the loader runs in arm7 or arm9?Who can help me? Thanks a lo in advance.

#64513 - natrium42 - Fri Dec 23, 2005 5:41 am

swzte wrote:
Is it 0x080000C0 or 0x08000000?

It's 0x080000C0.

swzte wrote:
Sencond, the loader runs in DS mode or GBA mode?

DS mode, of course. Can't go from GBA mode to DS mode.

swzte wrote:
Third, as we all know, ds has two cpus, arm7 and arm9, the loader runs in arm7 or arm9?Who can help me? Thanks a lo in advance.

Unless it's a menu loader, it only runs on ARM7, since it's the CPU that has access to the GBA slot at boot time.
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#64526 - swzte - Fri Dec 23, 2005 7:00 am

Thank natrium42 for you answer.If DS jumps to 0x080000C0 at boot, how is the code *.nds.gba stored in GBA Flash Card? As we all know, the first inctruction of the code is "0xEA00002E", this instruction is stored at 0x080000C0 or 0x08000000?