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Old 01-16-2008, 11:58 AM
Kurt Wall
 
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Default Re: LSI SCSI Cards - Upper Termination

Nick Havard <nick@nickhavardxyz.com> wrote:
> Hi
>
> I have the following two SCSI cards in my Ulta-10.
> * LSI 22801
> * LSI 8751SPE
>
> Both cards have the ability to UPPER TERMINATE, but I can't seem to find any
> reference to what this actually means. Does it refer to the use of SCSI
> device ID's, the use of the internal cable connectors or have some other
> meaning.
>
> I use these cards at either end of a SCSI bus for dual hosting a Sun
> Multipack 711 within Sun Cluster 3.0 (soon to be 3.1), so I only use the
> external connectors. Is there any significance in having these set or unset
> etc.


I believe "upper termination" is a synonym for "high byte termination."
Here's a snippet from one of my favorite SCSI technology disambiguators:

"While the Narrow SCSI bus uses only the lower byte, the Wide
SCSI bus consists of both a lower byte and an upper byte. When
connecting a Narrow SCSI peripheral to a Wide SCSI bus, you must
be very careful of how the bus is terminated. If you are
locating this Narrow peripheral at the end of the Wide SCSI bus
and you are using the built in terminators of the Narrow device,
you need a 68-pin to 50-pin adapter with high byte termination
or the upper byte will not be properly terminated."

(http://scsifaq.paralan.com/scsifaqanswers3.html#a6)

Kurt
--
"And what will you do when you grow up to be as big as me?"
asked the father of his little son.
"Diet."
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