>I think you're off the mark on this one. Every SCSI bus must have
>termination at the ENDS of the chain. SCSI busses are terminated at the
>motherboard (or card) end and you need ONE device attached to it to be
>terminated which acts as the other "end". I don't think it needs to be
>physically at the end of the cable.
>
>Also, I believe every device must be setup with a SCSI ID, there is no
>"default" setting. True, most stock internal drives are set to "0", but I
>have also seen them set up as ID "1". They do not"default" to any ID, but
>are set with jumpers as any device.
>
>Internal/External SCSI bus is no different. Both ends must be terminated
>and all devices must have unique ID set.
>
>Now some systems share a single SCSI bus for the internal and external
>drives, while others (like my Umax S900) have two separate SCSI busses on
>the motherboard allowing more devices to be connected. In either case, you
>need ONE device connected to the internal chain to be terminated and ONE
>device connected to the external chain to be terminated.
>
>Charles
That's just about my understanding of it too - all scsi hard drives
factory supplied onboard pre ide macs and clones are id 0 (not
necessarily for clones as my Pulsar was supplied with a HD at id 6} and
terminated. The scsi id's 0 - 7 and positions on the cable are entirely
flexible as long as the chain is terminated at both ends. The terminated
device has to be the last on the chain AFAIK.
An unterminated chain can give lots of strange problems as I have
encountered with quite a few sca 80 pin 2/4/9 gig Barracudas with no
termination option on the drive jumpers - I had to buy 80 pin adapters
with sca termination via jumpers on the adapter.
Pete
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