🚀 go-pugleaf

David Murray <dmurray@murraynet.net> writes:

>I know this goes contrary to what other people here are saying...  I have
>two Sparcstation IPX units both have external SCSI towers.  (not Sun made,
>just generic SCSI towers) and do not have any terminators on the end of the
>SCSI chain.  All devices work fine.  I do have the last device in the chain
>jumpered as termination but I found recently that on one system I forgot to
>do even that.  So there was no termination at all and it had been working
>fine.  I only noticed when I went to add an additional device.  Somebody
>told me once that since I am using 3-foot SCSI cables that termination
>isn't as important as if I was using 10 or 15 feet worth.
>--DavidM

It really depends on how the cabling it arranges, and a lot of other
factors. Because SCSI bus signals use 'transmission line' principles, the
termination is pretty important in most cases, but most newer SCSI devices
and controllers are fairly good at managing poor electrical conditions on
the bus cabling.

In a lot of cases it's a matter of gross cable length and how well shielded
the cabling it, but it's highly variable and your setup might be working
simply because the combinations are right for your devices to be able to
communicate at a slower speed than the optimum and you just don't notice the
difference in performance.

SCSI is a very forgiving standard now. It never used to be when devices,
controllers, etc. were made with very low electrical tolerances, but with
technology improvements come wider tolerances as well.

Regards,

Craig.
--
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