[4241] in linux-scsi channel archive
Re: SCSI confusion
daemon@ATHENA.MIT.EDU (Marc SCHAEFER)
Sat Jun 27 15:16:52 1998
From: Marc SCHAEFER <schaefer@alphanet.ch>
Date: 27 Jun 1998 20:22:51 +0200
Apparently-To: linux-scsi@vger.rutgers.edu
To: unlisted-recipients:; (no To-header on input)
McGee, Chris <CMMcGee@Pella.com> wrote:
> drive, and that seems simple enough, but there are also three jumpers
> labelled "Terminator power +5v from the Bus", "Terminator power +5v from
> Drive", and "Terminator power +5v to the Bus".
SCSI terminators must be powered by something. This is the TERMPWR line
on the SCSI bus. Usually, devices providing power also protect
themselves with a diode. Thus multiple power supplying is perfectly ok.
If you have problems, you could always try to use a drive as terminator
(which is probably the case), and do "Terminator power +5v from
Drive"
> What should these be set to for terminated/unterminated? Would
> anyone care to explain the mechanics of single-ended SCSI termination?
Both ends of the cable must be terminated. One of the end can be
on the SCSI host adapter, then terminate it (software, jumpers, etc).
Fast SCSI (10 MHz) cable length is maximum 3 m (safe: 2.4 m). *Minimal*
distance between disks is 15 cm.
For Ultra SCSI (20 MHz): 1.2/0.30
> Linux 2.0.34. I have two disks on the internal bus, and the second one
> kills the OS any time you access it. It's new (sat in a box in a closet
Do you have logs ?
-
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@vger.rutgers.edu
