I have never seen a DDS with an internal terminator.
Most have a jumper to supply power from the DDS to
the external terminator but no active terminator in
the DDS itself.
  Expect an unterminated SCSI bus to be flaky and
unpredictable. Some systems run fine for a long time without
termination, sometimes they won't see SCSI devices
at all. Don't know what your problem is caused by
but proper termination is always a good starting point.

                  Bob J. -- Ideal Computer Services
                  http://www.icsgroup.net



James B. Byrne wrote:

> On 4 Aug 2005 at 20:21, Bob J. wrote:
>
>
>>So you know, the terminator at the other (internal) end
>>of the MFIO's internal SCSI-SE bus is typically supplied
>>by enabling the first disk's built-in terminator. That
>>would be the device at the end of the ribbon cable.
>
>
> That would be the DDS then.  The new drive is attached to the
> controller via a 50 socket crimp connector located between the DDS,
> which is at the end of the ribbon cable, and where the wiring
> harness disappears into the guts of the machine.
>
> I always believed that if you improperly terminated a SCSI chain
> then you would have more serious problems than simply not seeing a
> single device.  I should think that the system would fail to boot
> at all.  Am I mistaken?
>
> Regards,
> Jim
>
>
> --
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>

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