Hi Patrick,
A "925 at home" sounds like my support office 925 with original HP-IB
interfaces that can only support the older C1511A - 1.3Gb DDS drive
without data compression. This drive only works well with the 60m tapes
(HP's red label) and can never read a tape written with hardware data
compression.
If you have the hw compression drives (C2478@,A3183A) on your 939 and
927, use DEVCTRL.MPEXL.TELESUP to disable compression. Watch out: the
compression drive may have the permanent compression dip switch set!
Regards
Fred Metcalf
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Patrick Anderson wrote:
>
> I have an odd situation that is probably hardware related, but here is
> the scenario.  I have a 959 running 5.0, and a 927 running 5.5 at work.
>  I can store and restore tapes between the two machines all day long.
> I have a 925 at home with 4.0.  I can restore tapes made on the 925 to
> the 959 and 927, but I can't restore any tapes to the 925 made on
> either the 959 or 927.
>
> Is there some option, or dip switch on the DDS drives that's enabling
> something.  Anyone have any ideas?
>
> TIA

Sounds familiar.  You don't mention the types or product numbers
of your various DDS devices (and don't tell me, 'cause they
probably won't mean anything to me -- I'm a software kind o' guy),
and you don't tell us what the error reported is, so we can't
remotely debug your problem.

But we did have a problem with an early version of one of the
DDS drives with head alignment problems.  Our original alignment
spec was a little too generous, so one drive (in spec but skewed
towards the "left" limit") might not be compatible with another
drive (in spec, but skewed towards the "right" limit).  We did
catch this problem before release, and our Manufacturing guys
tell us that no drives with the generous alignment specs ever
shipped.  But somehow, your drive might have drifted out of spec.

We've also seen some problems with dirty tape drives.  Can I
assume that you've carefully and thoroughly cleaned the drives
in question?  DDS drive are notorious for getting dirty.

I can't imagine this to be a software problem.  We (us software
guys) test cross-release STORE compatibility all the time, and
the releases you've mentioned are all supported (and therefore
in our test matrix).

--
Jon Cohen
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Hewlett Packard -- Commercial Systems Division

(The opinions expressed here gotta be mine, 'cause no
one else will own up to 'em.)