rkiesling <> wrote:
>
> Hello, all,
> I would like to find information about terminating an Ultra
> 60's external SCSI interface. The system occasionally tries
> to write and reset the SCSI device, and then times out with
> a failure.
Write to what? If there's nothing attached, the system shouldn't
"occasionally try to write". Are you sure the error is for the external
bus and not the internal bus?
> I cannot find information in the Sun docs about
> whether an external terminator is needed if there are no
> devices attached to the port, or about the SCSI termination
> on the mainboard, if that is only related to the internal
> SCSI assembly. ISTM the external port should be
> self-terminating, but I'm only guessing.
Termination isn't needed if there's no device attached. First, the bus
shouldn't be in use, so the OS shouldn't care if it's working or not.
Second, without any devices attached, the length of the bus is so short
that reflections off one end won't confuse the signalling. As long as
there's proper internal termination, it'll all get sucked up before
anything is affected.
--
Darren
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