DMA copy to CRAM

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ob1
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DMA copy to CRAM

Post by ob1 » Sat Dec 30, 2006 8:59 pm

Has anyone already tried (and succeded) to DMA copy from VRAM (obviously) to CRAM ?
Would it be faster than a DMA transfer from ROM or Work RAM (obviously no) ?

Nevertheless, with DMA copy, the CPU can keep on working whereas with DMA transfer, it is stalled. I guess that for transferring data to CRAM (1024 bytes max), I don't have to worry about CPU stalling.

Stef
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Post by Stef » Sat Dec 30, 2006 9:56 pm

You just can't transfert from VRAM to CRAM.
When you do a DMA operation, you can only choose destination :
VRAM / CRAM / WSRAM
So during DMA "copy" operation, destinatin almost becomes the source.

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