[comp.sys.ibm.pc] Shared DMA channel -- is it possible?

davej@uw-entropy.ms.washington.edu (Dave Jenner) (03/30/89)

I need to configure an IBM PC/XT with four devices that use a DMA channel:
Floppy Disk(channel 2), Hard Disk(3), Tape Drive(1), and IEEE-488 GPIB
Interface(?).  It is highly unlikely that the Floppy Disk and the GPIB
Interface will be used simultaneously, so the most likely way to try it is
with the Floppy Disk and the GPIB Interface sharing DMA channel 2.

Now the Flopppy Disk doesn't seem to mind that the GPIB Interface is also
set to DMA Channel 2, but the GPIB Interface will not function properly with
the Floppy Disk Adapter in the system.

Is this soley a hardware problem, or can I somehow momentarily disable the
Floppy Disk for the interim of use of the GPIB Interface with the appropriate
software?  Any comments on this situation, (especially software!) will be
greatly appreciated.


-- 
Dave Jenner                      (206) 543-6182, 543-2888 (Message)
Department of Astronomy, FM-20   BITNET: davej@uwaphast
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