Maximum DMA on XT and AT

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#5355

From: Dave Rajnauth
Date: Thu, 21 Mar 1991 15:10

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I have been reading the the XT only supports under 0.5Mbyte/sec
DMA although the DMA chip supports over 1Mbyte/sec.  It was suggested
that this was because of the 8088 being able to access the bus during
the DMA cycles and memory refresh (which uses DMA channel 1).

Does anyone know how to bump up this DMA speed?  Should I expect
this speed on the AT?  How can I get the max. DMA speed from
a XT or AT?   

Thanks,
Dave Rajnauth

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Message-ID: <1991Mar21.151029.25820@sparrms.ists.ca>

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Path: arc1-ca.pugleaf.net!utzoo!utgpu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!ists!sparrms!sparatd!ddr
From: ddr@sparrms.ists.ca (Dave Rajnauth)
Newsgroups: comp.os.msdos.programmer
Subject: Maximum DMA on XT and AT
Message-ID: <1991Mar21.151029.25820@sparrms.ists.ca>
Date: 21 Mar 91 15:10:29 GMT
Organization: Spar Aerospace Ltd, Toronto, Canada
Lines: 11