On Wed, 17 Nov 1999, COPLIN, Nicholas. wrote: > the questions I have are: > 1) what memory map does the DMA see? is it the one defined by the 6510 port > or are the port lines also Z-stated? >From my somewhat limited experience with the REU, it is the one defined by the 6510. > 2) if the mem-map is still the 6510 view, then do write throughs to under > the ROM still write to RAM I think so, yes. The DMA device simply replaces the processor. > 3) how does one DMA to write to the 6510 ports 0x0000 and 0x0001??? One doesn't. It's also difficult to write to the memory locations 0 and 1 with the 6510, but it's possible and I've done it. > 4) can the IRQ /NMI lines be "read" from the expansion port or are they > buffered only for generating requests? they look unbuffered to me..... Yes, they are bidirectional in that sense. > The contents of this email (including any attachments) may be > privileged and confidential. Does this mean that your company is going to develop an accelerator cartridge for the C64? :-) Marko - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail cbm-hackers-request@dot.tcm.hut.fi.
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