From owner-freebsd-hardware Tue Aug 25 05:41:15 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id FAA21985 for freebsd-hardware-outgoing; Tue, 25 Aug 1998 05:41:15 -0700 (PDT) (envelope-from owner-freebsd-hardware@FreeBSD.ORG) Received: from dingo.cdrom.com (ppp-d9.dialup.hilink.com.au [203.2.144.19]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id FAA21978 for ; Tue, 25 Aug 1998 05:41:12 -0700 (PDT) (envelope-from mike@dingo.cdrom.com) Received: from dingo.cdrom.com (localhost [127.0.0.1]) by dingo.cdrom.com (8.9.1/8.8.8) with ESMTP id FAA00441; Tue, 25 Aug 1998 05:36:45 GMT (envelope-from mike@dingo.cdrom.com) Message-Id: <199808250536.FAA00441@dingo.cdrom.com> X-Mailer: exmh version 2.0.2 2/24/98 To: "Daniel O'Connor" cc: john hood , Joe Gleason , freebsd-hardware@FreeBSD.ORG Subject: Re: UDMA Support In-reply-to: Your message of "Tue, 25 Aug 1998 15:59:13 +0930." <199808250629.PAA06960@cain.gsoft.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Tue, 25 Aug 1998 05:36:44 +0000 From: Mike Smith Sender: owner-freebsd-hardware@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > > > > FreeBSD 3.0 supports IDE DMA. SCSI disks will give better performance > > > in multiple-disk or high load scenarios. > > -current supports DMA, but not Ultra DMA, which is faster and has > > CRC error checking. (I haven't got an Ultra DMA motherboard and > > drive to code/debug on.) This is not much of a problem yet, as > > IDE drives cannot yet use all the bandwidth of standard DMA, but > > it looks like it will be soon, the way IDE drives are going. :) > And the less time the computer spends moving data off your HD means more > time to render Quake frames (or something). > > I have a UDMA mobo and 3 UDMA drives, so I can test it for you. I could > probably code some of it if I knew what to do =) (ie the UDMA spec) You want the ATA-4 spec (ftp://fission.dt.wdc.com) and the datasheet for the interface chipset you have (probably http:// developer.intel.com). -- \\ Sometimes you're ahead, \\ Mike Smith \\ sometimes you're behind. \\ mike@smith.net.au \\ The race is long, and in the \\ msmith@freebsd.org \\ end it's only with yourself. \\ msmith@cdrom.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hardware" in the body of the message