From owner-freebsd-scsi Wed Feb 19 11:51:48 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id LAA14642 for freebsd-scsi-outgoing; Wed, 19 Feb 1997 11:51:48 -0800 (PST) Received: from sax.sax.de (sax.sax.de [193.175.26.33]) by freefall.freebsd.org (8.8.5/8.8.5) with SMTP id LAA14628 for ; Wed, 19 Feb 1997 11:51:24 -0800 (PST) Received: (from uucp@localhost) by sax.sax.de (8.6.12/8.6.12-s1) with UUCP id UAA14428 for scsi@freebsd.org; Wed, 19 Feb 1997 20:50:40 +0100 Received: (from j@localhost) by uriah.heep.sax.de (8.8.5/8.6.9) id UAA23294; Wed, 19 Feb 1997 20:21:27 +0100 (MET) Message-ID: Date: Wed, 19 Feb 1997 20:21:27 +0100 From: j@uriah.heep.sax.de (J Wunsch) To: scsi@freebsd.org Subject: Re: About to go SCSI - advice? References: <199702191244.HAA01017@hda.hda.com> X-Mailer: Mutt 0.55-PL10 Mime-Version: 1.0 X-Phone: +49-351-2012 669 X-PGP-Fingerprint: DC 47 E6 E4 FF A6 E9 8F 93 21 E0 7D F9 12 D6 4E Reply-To: joerg_wunsch@uriah.heep.sax.de (Joerg Wunsch) In-Reply-To: <199702191244.HAA01017@hda.hda.com>; from Peter Dufault on Feb 19, 1997 07:44:25 -0500 Sender: owner-freebsd-scsi@freebsd.org X-Loop: FreeBSD.org Precedence: bulk As Peter Dufault wrote: > > Rule #1: Turn off termpower! On any drive you're going to connect... > > let them take termpower from bus, and let the controller provide this > > to the bus, nobody else. > > No, Joerg. Any device that can become an initiator must supply > terminator power (so Simon must have more than one device with > TERMPWR to meet the letter of the spec). Other devices can as long > as they don't exceed the total maximum current (which is huge - I > think it is something like 5 amps and is driven by regulatory > issues). The discussion is somewhere near the beginning of the > spec. I've got nothing but problems in the past by having disk supplying termpower, and since switched to leave this solely to the host adapter. Maybe these drives were faulty wrt. standard, i don't know. -- cheers, J"org joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE Never trust an operating system you don't have sources for. ;-)