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Hardware > uhm.. how to boot a gba as a gbc

#9356 - f00l - Sat Aug 02, 2003 4:48 pm

I know about the switch.. but is it possible to do it with a rom ?
btw.. how does the gba/gbc thing works ? does it start an emulator ? or a special Z80 chip ?

Thankx,

f00l
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#9358 - Lord Graga - Sat Aug 02, 2003 5:40 pm

As far as I remember, then the GBC has a pin more or less on the cart. The GBA simply checks if the pin is conencted or not.

The emulation is done by a Z80 chip.

#9359 - tepples - Sat Aug 02, 2003 6:10 pm

There's actually a switch on the side of the cart edge connector that GBC carts press and GBA carts don't. If you want to use a GBA flash cart to develop GBC programs, you're going to need a device that presses down the switch and translates between GBA and GBC edge connector protocols. Such a device is called a "GB bridge."
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#9361 - f00l - Sat Aug 02, 2003 8:03 pm

yeah I know about the chip :)

but I was wondering if I could get to the emulation Chip ,
like this :

ldr r1,= "z80 emu chip"
ldr r2,=0xFF
strb [r2,r1]
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#9365 - tepples - Sun Aug 03, 2003 12:07 am

There is no known way to run 8-bit programs from GBA-protocol ROM or from EWRAM, except through a software emulator loaded into IWRAM.
_________________
-- Where is he?
-- Who?
-- You know, the human.
-- I think he moved to Tilwick.