From owner-freebsd-hackers  Mon Jun  7 23:55:57 1999
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To: Jos Backus <Jos.Backus@nl.origin-it.com>
Subject: Re: The choice of MAXPHYS 
Cc: Wilko Bulte <wilko@yedi.iaf.nl>, zzhang@cs.binghamton.edu,
	freebsd-hackers@FreeBSD.ORG
In-reply-to: Your message of "Thu, 03 Jun 1999 23:12:16 +0200."
		<19990603231216.A36464@hal.mpn.cp.philips.com> 
References: <19990603231216.A36464@hal.mpn.cp.philips.com>  <19990603172907.A20792@hal.mpn.cp.philips.com> <199906031730.TAA00686@yedi.iaf.nl> 
Date: Tue, 08 Jun 1999 00:53:54 -0600
From: Warner Losh <imp@harmony.village.org>
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In message <19990603231216.A36464@hal.mpn.cp.philips.com> Jos Backus writes:
: On Thu, Jun 03, 1999 at 07:30:20PM +0200, Wilko Bulte wrote:
: > 20 bits. But older cards can do no more than 64 kB.
: 
: Indeed, 20 bits (=1 Mbyte) for the address, 16 bits for the transfer counter
: (offset).

Isn't that 24 bits for addresses?  You can dma from an ISA card to
anywhere in the first 16M...

Warner


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