From owner-freebsd-hardware Wed Jan 5 5:19:31 2000 Delivered-To: freebsd-hardware@freebsd.org Received: from gilgamesch.bik-gmbh.de (gilgamesch.bik-gmbh.de [194.233.237.194]) by hub.freebsd.org (Postfix) with ESMTP id BE7CE15385 for ; Wed, 5 Jan 2000 05:19:28 -0800 (PST) (envelope-from cracauer@gilgamesch.bik-gmbh.de) Received: (from cracauer@localhost) by gilgamesch.bik-gmbh.de (8.9.3/8.7.3) id OAA78766; Wed, 5 Jan 2000 14:19:15 +0100 (MET) Date: Wed, 5 Jan 2000 14:19:15 +0100 From: Martin Cracauer To: Peter Jeremy Cc: Mitch Collinsworth , hardware@FreeBSD.ORG Subject: Re: differences between SCSI and EIDE [was: wanna buy an EIDE harddisk ... 5400 or 7200 for home use (noise)] Message-ID: <20000105141915.A78488@cons.org> References: <200001041610.LAA15549@benge.graphics.cornell.edu> <00Jan5.122026est.40333@border.alcanet.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.4i In-Reply-To: <00Jan5.122026est.40333@border.alcanet.com.au>; from Peter Jeremy on Wed, Jan 05, 2000 at 12:20:26PM +1100 Sender: owner-freebsd-hardware@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org In <00Jan5.122026est.40333@border.alcanet.com.au>, Peter Jeremy wrote: > > An EIDE "bus" is a random piece of ribbon cable with TTL logic levels, > no termination and (from memory) insufficient ground wires. This was > not a problem at low speeds, but as the speeds get higher, the cable > looks more like an unterminated transmission line and the reflections > eat into the noise immunity. This is one of the greatest concerns to me regading IDE: On bad cables or drives, it falls back to lower speeds. This is not only a speed change, the drive is run in an older IDE mode. That's bad, because you loose the other fancy new features as well, including error handling. While we're talking about error recovery: After all those years of getting it right in SCSI/ahc, how much time will to keep to bring ata up to the same level? How many people step on ata as hard as people did on CAM/ahc? What about controllers? Isn't PIIX4 by far the most polished and tested controller in ATA? Martin -- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Martin Cracauer http://www.cons.org/cracauer/ BSD User Group Hamburg, Germany http://www.bsdhh.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hardware" in the body of the message