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DS development > Booting .gba from DS Mode on GBAMP

#54583 - Kate - Tue Sep 20, 2005 4:50 pm

Hi,

Does anyone have any information/code example on how to boot a GBA programme from DS mode with GBAMP inserted. Or failing that just how to boot a GBA app from DS mode on an ordinary cartridge.

Thanks

Kate

#54591 - IxthusTiger - Tue Sep 20, 2005 6:27 pm

If you mean emulation, nope sorry, if you mean jump from DS mode to GBA mode, no can do either. Gotta start it in GBA mode or nuthin'

However, if you put a .gba file that is <200k on the gbamp, you should be able to run it even if you have DS files on there (thanks to chishm and Mighty Max) but you still have to boot the GBAMP in GBA Mode, not DS mode

#54612 - josath - Tue Sep 20, 2005 9:02 pm

You CAN jump from DS -> GBA mode (but not the other way around).

The only problem is, you have little control over it, it basically resets, and starts execution at the beginning of GBA cartridge space (0x0800000 + some bytes)

The following piece of code will make the DS go into GBA mode: (run this on the ARM7)
Code:

    mov    r2, #0x40
    ldr    r12, =0x11B8      @ call some routine in the bios
    bx     r12

From: http://www.bottledlight.com/ds/index.php/Main/GBAMode

Note: I have successfully done this using both the EZF3 cartridge, and the neoflash 512 cartridge. I've actually posted about it several times before on this forum. search for more info.

#54664 - Kate - Wed Sep 21, 2005 12:23 pm

Thanks for the info.