Re: New ][ Hardware - DSP board (soon!)

[kpopple@imp.sim.es.com (Ken Poppleton)]

In article <C32K0x.2pA@javelin.sim.es.com>, kpopple@imp.sim.es.com (Ken Poppleton) writes:
> In article <1993Feb25.210713.18808@mcs.anl.gov>, b45075@opal.ctd.anl.gov (Nathaniel Trost) writes:
> > Hmm, unless I'm mistaken it doesn't look like the board supports DMA transfers
> > to/from the GS memory.  Does the board support DMA?
> 
> You are correct, I did not get a DMA controller on the board,  I would
> like to have one, but have not had the time to put that in.  This

OK I'll post a response to my own posting.

After thinking about this a bit, I may be able to do it as a later
upgrade to the board.  How important is this to everyone?  Is there
someone who would be willing to discuss how DMA is used on the
GS?  The GS has more than 64K of memory, so how does a DMA controller
write or read memory outside the 64K memory the io slots are in?  Please
let me know more about the GS if this is what YOU want.  Is there some
built in DMA in the GS?

If there is a built in DMA controller, then what is required for
a board to support DMA.  (on the AppleIIe, the board must have
a DMA controller itself, is this true of the GS?)

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Ken Poppleton 
kpopple@imp.sim.es.com
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