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From: Thomas Gellekum <thomas@ghpc8.ihf.rwth-aachen.de>
Message-Id: <199506141502.RAA02448@ghpc6.ihf.rwth-aachen.de>
Subject: Re: Problem adding a second SCSI disk on 1542CF
To: dufault@hda.com (Peter Dufault)
Date: Wed, 14 Jun 1995 17:02:48 +0200 (MET DST)
Cc: thomas@ghpc8.ihf.rwth-aachen.de, hardware@freebsd.org
In-Reply-To: <199506141332.JAA19021@hda.com> from "Peter Dufault" at Jun 14, 95 09:32:56 am
Organization: Institut f. Hochfrequenztechnik, RWTH Aachen
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Peter Dufault wrote:
> 
> >From the comp.periphs.scsi FAQ:
> 
> ====
> QUESTION: What is the problem with the Adaptec 1542C and external cables?
> ANSWER From: Scot Stelter, Adaptec  (Product Manager for the AHA-1540)
> ====
[...]
> 
> After surveying the cable market and many of our customers, we decided
> that bad cables were going to be here for a while, and we had to make
> the 1540C as forgiving as the 1540B was.  At the end of April we made
> a change to the AHA-1540C that involved using a passive filter to
> reduce the slew rate of the ACK line, the signal that the host adapter
> drives during normal data transfers. 

Which year was that?  My card was produced in 1993.  Can anyone tell
more about this filter?  Ripping out the good cables from one of our
VAXstations just for testing is unfortunately not an option; our
admin is not amused about it.

tg