*BSD News Article 15301


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Newsgroups: comp.os.386bsd.questions
Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!agate!howland.reston.ans.net!ira.uka.de!smurf.sub.org!flatlin!bad
From: bad@flatlin.ka.sub.org (Christoph Badura)
Subject: Re: 386bsd with >16M
Organization: Guru Systems/Funware Department
Date: Wed, 28 Apr 1993 17:25:56 GMT
Message-ID: <C67F39.Eov@flatlin.ka.sub.org>
References: <g89r4222.735937533@kudu> <C677BI.20Dz@austin.ibm.com>
Lines: 18

In <C677BI.20Dz@austin.ibm.com> guyd@austin.ibm.com (Guy Dawson) writes:
>The ISA bus has 24 address lines so ANY card attempting DMA can only
>do so with the first 16MB of memory.

That's only correct for busmaster DMA devices.  Devices that use the
mainboard's DMA controller have the same problems for similar reasons
though.

>> Is this due to problems with possibly trying to do DMA from the
>> network card (WD)?  
>Almost certinally...

Most certainly not because the WD80xx driver doesn't use DMA.
-- 
				Christoph Badura  ---  bad@flatlin.ka.sub.org

Personally, I don't care whether someone is cool enough to quote Doug
Gwyn--I only care whether Doug Gwyn is cool enough to quote. -- Larry Wall