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DS development > How to set up the PHI clock to 10MHz in DS MODE?

#94832 - jandujar - Wed Jul 26, 2006 9:43 am

Maybe somebody could help me.

I need to know how to setup the PHI clock to 10MHz or something similar in DS Mode.

Maybe I need to set up the WAIT_CR register?

Please show me how.

Thx
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#96434 - jandujar - Thu Aug 03, 2006 12:18 pm

looking at http://nocash.emubase.de/gbatek.htm section
DS Memory Control - Cartridges and Main RAM

I found that the bits 5-6 of 4000204h configures the 32-pin GBA Slot PHI-pin out (0-3 = Low, 4.19MHz, 8.38MHz, 16.76MHz)

Which is the correct answer to change the GBA PHI to 4,19MHZ?

- (*(u16*)(0x4000204))|=16;

- (*(vuint16*)(0x4000204))|=16;

I don't have an oscillator to verify the code.
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#96436 - Mighty Max - Thu Aug 03, 2006 12:29 pm

(*(vuint16*)(0x4000204)) &= ~(BIT(5) | BIT(6)) ;
(*(vuint16*)(0x4000204)) |= BIT(5)
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GBAMP Multiboot

#96437 - jandujar - Thu Aug 03, 2006 12:31 pm

thx
_________________
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http://www.dsrobot.com