From owner-aic7xxx Sun Feb 20 11:57:45 2000 Delivered-To: aic7xxx@freebsd.org Received: from lacrosse.corp.redhat.com (lacrosse.corp.redhat.com [207.175.42.154]) by hub.freebsd.org (Postfix) with ESMTP id D597F37B939 for ; Sun, 20 Feb 2000 11:57:35 -0800 (PST) (envelope-from dledford@redhat.com) Received: from redhat.com ([10.0.0.25]) by lacrosse.corp.redhat.com (8.9.3/8.9.3) with ESMTP id OAA30449; Sun, 20 Feb 2000 14:56:28 -0500 Message-ID: <38B047BA.2A66E716@redhat.com> Date: Sun, 20 Feb 2000 14:59:54 -0500 From: Doug Ledford Organization: Red Hat, Inc. X-Mailer: Mozilla 4.7 [en] (X11; U; Linux 2.2.14-1.1.0 i686) X-Accept-Language: en MIME-Version: 1.0 To: Philipp Scherer Cc: aic7xxx@FreeBSD.ORG Subject: Re: References: <200002201835.SAA15086@saturn.t30.physik.tu-muenchen.de> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-aic7xxx@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Philipp Scherer wrote: > > Re:timeout hang on boot > > ok i will look then for scsi termination problems again. > could it be a problem that i have a T-like configuration > of the 50 pin narrow branch? With the ribbon that came > with the mobo there is a connection from the 50 pin connector > on one side to the cdroms and on the other side to the external > connector which is connected to the zip drive. > > zip(term.)----ext.conn.-----host ad.(auto)--cdrom----cdrom(term.) This is almost guaranteed to cause problems. First, I'm not sure, but I wouldn't be the least bit suprised if termination were always enabled for the 50 pin interface, even when set to auto. That would over terminate the bus. Second, I wouldn't be suprised if your total cable length exceeds the 1.5m maximum cable length. Third, the typical 25 pin connector on the zip drives and the zip drive cables interfere with the transmission wave properties of a SE SCSI bus, so that can cause additional errors on faster devices (the zip drives don't care because they only run in async mode, but they went so cheap on construction that you almost can't put a zip drive on the same SCSI bus as anything else, which pisses me off, especially if you are anywhere near your cable length limits and any other device wants to run in sync mode). -- Doug Ledford http://people.redhat.com/dledford Please check my web site for aic7xxx updates/answers before e-mailing me about problems To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe aic7xxx" in the body of the message