Hallo Bogax, > I've never used the thing and perhaps I misunderstand what you're > saying, but you shouldn't need two 8237s. > Memory to memory is done with two DMA channels, channel 0 is the > source and channel 1 is the destination. Found the section so you were right, thanks! But now the bad news: The the 8237 needs FOUR cycles for every single operation. A DMA of one byte from memory to memory would cost eight cycles. OK, even when running on 1 MHz it still is a better performance then when the CPU had to do the job. But you can forget the real 1 MHz performance the REU can run. Until now I haven't found an idea to speed things up except using 2 IC's. But this only would permit 256KB/sec. Anyone has ideas? Groetjes, Ruud http://Ruud.C64.org/ - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail cbm-hackers-request@dot.tml.hut.fi.
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