From: COPLIN, Nicholas. (ncoplin_at_orbeng.com.au)
Date: 1999-11-17 03:44:26

Hi All,
does anyone know of a good write up on DMAing to the C64 from the expansion
port? I'm sure some of you know the answers without looking them up....

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?
2) if the mem-map is still the 6510 view, then do write throughs to under
the ROM still write to RAM
3) how does one DMA to write to the 6510 ports 0x0000 and 0x0001???
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.....


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