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Hardware > DMA3 Transfer -> VRAM not finished, vblank period over

#9360 - wbb - Sat Aug 02, 2003 7:26 pm

Hello

I have read some info (cowbite & gbatek) about DMA Register. What would happen if I start a DMA3 transfer to VRAM in the Vblank period and the transfer is not finished (bad, bad) when the Vblank period is over? Or how the GBA react to it? Screen messed up?

Best regards
Bastian

#9366 - tepples - Sun Aug 03, 2003 12:09 am

GBA VRAM can be read or written at any time, and it's even faster than EWRAM. There may be a few wait states if you write to VRAM during draw, and you might get a little tearing, but it won't just get lost like on the GBC or (worse) interfere wtih drawing like on the NES.
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#9396 - wbb - Sun Aug 03, 2003 7:33 pm

Hello

Thx for the quick answer, good to know that no data is lost.

Best regards
Bastian