How enhancement chips can help DMA speed.

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psycopathicteen
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Joined: Wed May 19, 2010 6:12 pm

How enhancement chips can help DMA speed.

Post by psycopathicteen » Mon Apr 04, 2016 9:04 pm

I used to think that enhancement chips couldn't help with speeding up DMA, since they can't touch the PPU or DMA registers, but now I realized they can be used to cut down on the DMA setup overhead in two ways.

1) Everything to be DMAed can be copied into one huge buffer ahead of time. No need to update $43x2 and $43x3 more than once per frame.

2) The DMA routine can be modified while the CPU is running it.

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