HP3000-L Archives

April 1998, Week 5

HP3000-L@RAVEN.UTC.EDU

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
James Trudeau <[log in to unmask]>
Reply To:
James Trudeau <[log in to unmask]>
Date:
Mon, 27 Apr 1998 13:36:23 -0500
Content-Type:
text/plain
Parts/Attachments:
text/plain (54 lines)
Howdy,

AVR (shudder).  Wirt has it correct although I would add that the
tape media itself can "have a problem".  I was burned by this
quite badly and wound up with HPRC involved (couple years
ago, I think the OS at that time was 4.0) and what it comes
down to is the system cannot figure out what the devil it is
trying to process, labelled/unlabelled, where's the start point, etc.
The problem made me really old but I won't bore you with the
gruesome details.
jt


-----Original Message-----
From:   WirtAtmar [SMTP:[log in to unmask]]
Sent:   Monday, April 27, 1998 11:42 AM
To:     [log in to unmask]
Subject:        Re: Scsi tape drive error

Sam Knight asks:

> Does anyone know the meaning of the error message below, it displays each
>  time a DAT tape is loaded?  The indicator lights are normal (green).  Could
>  not find the message in the MPE/iX Error Message Manual Vol I, II or III.
>
>  AVR Failure on LDEV 7
>  Status FFD F0071, #23 "AVR6

I must admit that I'm guessing what AVR stands for. I've always taken it to
mean something like "Automatic Volume Recognition," but to be absolutely
honest, you can supply your own translation and perhaps be more accurate.

As to what's causing the problem, there too I can only guess, but as I do our
own maintenance on our DDS drives, I have found that this error commonly
occurs because of two somewhat distinct problems. The first is that the
rotating read/write head has a bit of dirt attached to it so that it is
causing the tape to fly off of the surface of the helical head -- and thus
incompletely reading the load point prefix data from the tape and therefore
cannot properly read or recognize the volume data information. The solution
here is simple: clean the tape head by running a cleaner cartridge through the
tape once or twice.

The second source of this problem has been the presence of dirt in the path of
the IR-phototransistor pair that seeks out the black-clear-black load point on
the tape. Pressurized dry air works well to clear this problem -- but you need
to remove and disassemble your drive to perform this operation.

Other sources of this problem would be that the read/write electronics in the
drive have failed, but that is a relatively remote possibility. But if that
should happen, there's almost nothing you can do to remedy that other than
call HP.

Wirt Atmar

ATOM RSS1 RSS2