----- Original Message -----
From: <trag at io.com>
To: <undisclosed-recipients:>
Sent: Thursday, July 09, 2009 4:05 PM
Subject: Re: Classic mac fun (and some questions)
   
(continued...again...)
 From: "Jeff Walther" <trag at 
io.com
 To: cctech at 
classiccmp.org
 User-Agent: SquirrelMail/1.4.17
 MIME-Version: 1.0
 Content-Type: text/plain;charset=iso-8859-1
 Content-Transfer-Encoding: 8bit
 X-Priority: 3 (Normal)
 Importance: Normal
> Date: Thu, 9 Jul 2009 12:00:48 -0400
> From: Ethan Dicks <ethan.dicks at 
gmail.com
  I tried to look that up and found it easy to see
that the IIfx needed
 something odd (I couldn't find specifics), so well done there.  It
 would be interesting to get the details to see where Apple went off
 the rails from the SCSI spec. 
 IIRC, it's a matter of adding a capacitor and maybe a resistor to a
 regular terminator.  There's an Apple Technical Note or similar available
 somewhere.  I probably have a copy squirreled away on my hard drive at
 home.   And I think I remember that they use a somewhat higher value
 capacitor (so add a smaller one in parallel on an existing terminator) and
 a lower resistance (so again, add a resistor in parallel).   But I could
 be misremembering.
 Again, IIRC, the IIfx's SCSI was too noise sensitive.  But I've also
 heard/read that that was only true for the early production run and that
 the later built machines did not need the funny terminator.