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From: "Serge A. Babkin" <babkin@hq.icb.chel.su>
Message-Id: <199602061303.SAA17283@hq.icb.chel.su>
Subject: Re: Paul is manual-less tonight... inw() instruction?
To: pst@shockwave.com (Paul Traina)
Date: Tue, 6 Feb 1996 18:03:27 +0500 (GMT+0500)
Cc: hackers@freebsd.org
In-Reply-To: <199602060819.AAA00413@precipice.shockwave.com> from "Paul Traina" at Feb 6, 96 00:19:13 am
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> 
> Can anyone give me a quick description of how the i386 inw (in word)
> i/o instructions is suppoed to work?
> 
> does	foo = inw(port)
> 
> read low byte from port and high byte from port+1, or two sequential byte
> reads of port?

As far as I know it depends on hardware you are fetching bytes from. If
it supports 16-bit mode then one word read is done. If not then two
sequential byte reads are done.

-SB