second processor on a II:How?

[dpscholn@mtu.edu (Dan P. Scholnik)]

	I am thinking about making a 6809 interface card to hook up to a II+
or IIe (basically to save me the trouble of building a whole system) and I
was wondering how that was typically done, ala Z80 card and those 6502
accelerators. From the manual I see that pulling DMA low is the only way
(on a II+, anyway) to take the busses away from the 6502. How could another
processor take over the memory and leave the video pretty much as is? I
assume that the video can just be left alone to refresh the ram, but I don't
think the 6809 sits idle for half a cycle like the 6502. Any suggestions
from the many experts among you?
	I might also just make it a separate system that can communicate to
the apple via the slot. I just want a 6809 system to play with, plus the
fun of designing it.

Dan Scholnik

dpscholn@mtu.edu