From owner-freebsd-hackers Tue Dec 16 20:33:24 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id UAA06653 for hackers-outgoing; Tue, 16 Dec 1997 20:33:24 -0800 (PST) (envelope-from owner-freebsd-hackers) Received: from ns2.cetlink.net (root@ns2.cetlink.net [209.54.54.20]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id UAA06647 for ; Tue, 16 Dec 1997 20:33:18 -0800 (PST) (envelope-from jak@cetlink.net) Received: from hot1.auctionfever.com (ts1-cltnc-13.cetlink.net [209.54.58.13]) by ns2.cetlink.net (8.8.5/8.8.5) with SMTP id XAA20131; Tue, 16 Dec 1997 23:33:12 -0500 (EST) From: jak@cetlink.net (John Kelly) To: Mike Smith Cc: Mike Smith , FreeBSD Hackers Subject: Re: 3com 3c509 card Date: Wed, 17 Dec 1997 05:34:09 GMT Message-ID: <349c63b3.102223169@mail.cetlink.net> References: <199712170416.OAA01477@word.smith.net.au> In-Reply-To: <199712170416.OAA01477@word.smith.net.au> X-Mailer: Forte Agent 1.01/16.397 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by hub.freebsd.org id UAA06649 Sender: owner-freebsd-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk On Wed, 17 Dec 1997 14:46:08 +1030, Mike Smith wrote: >> I seem to have one 486 board running at 12 MHz ISA and clock doubled >> 50/100MHz DX4-100 CPU will no apparent problems. This has reduced my >> (measured) 8 bit I/O cycle time to 0.65 usec. I don't have a suitable >> method for measuring the 16-bit cycle time, but I'm hoping for nearly >> 4MB through this supercharged bus in 16-bit mode. > >You can expect that it will be half, based on the 6 clock/3 clock >ratio, so about 325ns. That would be an upper limit of 6MB, so with overhead maybe 4MB is attainable. I'll learn more when I get around to setting up the router and testing it. John