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From: Terry Lambert <tlambert@primenet.com>
Message-Id: <199711122201.PAA20601@usr05.primenet.com>
Subject: Re: make world time???/
To: tlambert@primenet.com (Terry Lambert)
Date: Wed, 12 Nov 1997 22:01:37 +0000 (GMT)
Cc: handy@sag.space.lockheed.com, roberto@keltia.freenix.fr,
        current@FreeBSD.ORG
In-Reply-To: <199711122019.NAA07092@usr09.primenet.com> from "Terry Lambert" at Nov 12, 97 08:19:03 pm
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> 1)	Allocate a buffer in low memory at some offset "x".
> 2)	Allocate a buffer in high memory at 16M + x
> 3)	Allocate a compare buffer somewhere.
> 4)	Schedule a bus mastering DMA read into the low memory
> 	buffer; wait for it to complete
> 5)	Copy the low memory buffer contents to the compare buffer
> 6)	XOR some non-zero pattern into the low memory buffer
> 7)	Copy the low memory buffer contents to the high memory buffer
> 8)	Schedule a bus mastering DMA read into the low memory
                                                   ^^^^ - UGH!
					I meant to say "high" here...
> 	buffer; wait for it to complete
> 9)	Compare the compare buffer contents against the low memory
> 	and high memory buffer contents.
> 10)	If the compare buffer contents matches the low memory buffer
> 	contents, set the "USEBOUNCEBUFFERS" flag on the controller.


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.