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Date: Wed, 21 May 1997 02:39:11 -0400
From: "Gary T. Corcoran" <garycorc@idt.net>
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To: Bruce Evans <bde@zeta.org.au>
CC: HARDWARE@FreeBSD.ORG
Subject: Re: isa bus and boca multiport boards
References: <199705210516.PAA05401@godzilla.zeta.org.au>
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Bruce Evans wrote:
>  On a P5/133, about 300 pointer dereferences can be
> done in the time it takes to do one i/o instruction.

I know this discussion was concerning I/O ports on the ISA bus,
but I'm curious if you know: How long does a single I/O (read or
write) take when accessing an I/O port on the PCI bus?

I _believe_ that in modern chipsets, for I/O addresses which are
supposed to be "PCI only" (higher than a certain address) that
the I/O operations do *not* appear on the ISA bus, and thus
shouldn't be limited by the ancient ISA I/O speeds - is this true?

Thanks,
Gary

Errr... given all the "Gary's" floating around on these lists,
make that:
Thanks,
Gary Corcoran