[649] in linux-scsi channel archive
Re: AHA-1740 SCSI errors
daemon@ATHENA.MIT.EDU (Kai Harrekilde-Petersen)
Mon Oct 2 19:18:07 1995
From: Kai Harrekilde-Petersen <khp@pip.dknet.dk>
To: jlewis@inorganic5.chem.ufl.edu (Jon Lewis)
Date: Mon, 2 Oct 1995 18:00:06 +0100 (MET)
Cc: linux-scsi@vger.rutgers.edu (Linux SCSI mailing list)
In-Reply-To: <Pine.LNX.3.91.951001203958.21657M-100000@inorganic5.chem.ufl.edu> from "Jon Lewis" at Oct 1, 95 09:05:17 pm
Jon Lewis writes:
> On Mon, 2 Oct 1995, Michael Weller wrote:
> > > Since the errors come from all the SCSI devices, I'm guessing it's either
> > > a cabling or driver problem. I doubt both controllers are bad, but we
> > > are using long cheap SCSI cables. Anyone have any ideas? I'm
> > ===============
> >
> > Why are you posing questions and then answer them yourself? Might it even
> Well...I didn't mean we were using totally crappy cables...just that they
> are run of the mill 50-pin ribbon cable and one is a bit on the long
> side...but case configuration requires it.
> A third system (used for WWW service primary DNS and as an X workstation)
> uses an NCR 53c810 and an identical cabling setup (2 internal HD's, no
> other SCSI devices) seems to have no such problems. That system was
> "upgraded" to the NCR board after having serious stability problems with
> first a 2940 and then 1540.
Adaptec controllers seem to require higher quality cabling than the
majority of controllers. This is probably due to Adaptec using higher
edge rates than other vendors: For example, the first batch AHA-1542C
had excessive problems with this, and Adaptec had to limit the edge
rate of one of the control signals (a simple RC network did it) to
make the 1542C as forgiving as the old 1542B's.
Check out the comp.periphs.scsi-FAQ for details.
Kai
--
Kai Harrekilde-Petersen <khp@pip.dknet.dk> Linux: choice of a GNU generation
>> Inside every little problem there's a BIG problem, struggling to get out <<
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