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From: tmh@prosun.first.gmd.de (Thomas Hoberg)
Newsgroups: comp.os.msdos.desqview
Subject: QEMM & Adaptec 1542
Keywords: Bus Master Blues
Message-ID: <646@bigfoot.first.gmd.de>
Date: 8 May 91 14:56:49 GMT
Sender: news@bigfoot.first.gmd.de
Reply-To: tmh@prosun.first.gmd.de (Thomas Hoberg)
Organization: GMD-FIRST, D-1000 Berlin 10
Lines: 20

I got a 1GB SCSI disk on my i486, some of which is used for DOS. I can't live
without QEMM, but it presents some problems for a bus mastering controller like
the Adaptec. Since physical and logical addresses aren't always the same in
QEMM's V86 mode the Adaptec sometimes gets invalid addresses for DMA. Windows
has the same problem in standard or 386 mode. I currently get around this by
using SMARTDRV loaded low, which seems to do physical IO via a buffer in
conventional memory, which is mapped 1:1. It works just fine, but it gobbles
up about 30k of conventional memory. Other solutions like a device driver
written by Roy Neese of Adaptec or the ASPI driver swollow up even more.
Has anybody got a better idea? Is there a Windows or QEMM specific device driver
for the Adaptec? 

-- tom 
----
Thomas M. Hoberg   | UUCP: tmh@bigfoot.first.gmd.de  or  tmh%gmdtub@tub.UUCP
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