m4 9914

From: Doc Shipley <doc_at_mdrconsult.com>
Date: Sat Aug 14 21:28:49 2004

Jay West wrote:

>> Cheesy/worn media?
>
> Nah, I tried two different tapes, both are brand new out of the box still
> shrinkwrapped, and I had cleaned the heads twice over the past two days.
>
>
>> I'd be for borrowing a differential SCSI adapter and trying the
>>original setup.
>
> I may give that a whirl, but... since the drive and host are definitely
> working fine at 800/1600, and because the drives offline diags (not
> involving the host) fail at 3200 and 6250, I don't think it's the interface
> in the drive. Maybe I'm missing something?

   The only thing I can really think of would be a mechanical issue,
like jerky or inconsistent tape movement at higher speed. But even that
wouldn't explain the fact that it doesn't even try at 3200bpi.

   The reason I suggested replacing the diff interface card is that I've
mixed and matched the internal boards in the old Exabyte EXB-8200 8mm
drives and gotten really weird behavior. If the firmware revs in the
contributing drives weren't _very_ close, it was a crapshoot. I have no
idea if that could be the case with your drive.

   I do diagnostics from a very low-tech perspective. If Device X was
working or supposedly working before I altered it and it doesn't work
now, I figure the odds are high that the alteration is a contributing
factor. If I don't have the docs or the equipment to do more specific
testing, going back to the original configuration is my first step.


        Doc
Received on Sat Aug 14 2004 - 21:28:49 BST