ephraim@think.com (Ephraim Vishniac) (07/31/90)
I recently posted the story of my IIfx SCSI woes, which were
apparently cured by a change of cabling. The most promising
explanation came from Dolf Starreveld, who pointed out to me that
stubs (side branches of the SCSI bus, "bridge taps" in another
respondent's terminology) are a Bad Thing.
I thought initially that Dolf was barking up the wrong tree, since I
had trouble even when the only external SCSI device was an Apple
CD-ROM player. Apple, surely, knows how to build SCSI devices.
Wrong.
I opened up my CD player and found that the actual drive is connected
to a several-inch-long stub, instead of tapping the bus between the
external connectors. It seems that lengthening my external bus reduced
the nasty effects of this design error to the point that my internal
disk doesn't get confused by the signal reflections.
Are Apple CD players still made this way? If so, it looks like it's
time for a change.
--
Ephraim Vishniac ephraim@think.com ThinkingCorp@applelink.apple.com
Thinking Machines Corporation / 245 First Street / Cambridge, MA 02142
One of the flaws in the anarchic bopper society was
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