Gunther,

According to the field service manual a termination code of 77 means that the
drive is not in TU/TA81 mode.
Before using test 04 you should execute test 49.

This is from the book:

Test requirements
Tape should be unloaded.
Set the jumper on the servo control board(W 1) in the 1-2 position.

Test description
Test 49 enables auto load on power up, displays the unit identifier, and sets
up the power down timer for one minute if no tape motion has occurred.

Return the jumper to the original position

Possible termination codes

00		test is succesfull
71		Invalid operator sequence
73, 74 	Backup memory is not write enabled
75, 76	Bad backup memory

Maybe you need help to find the jumper.....
The servo control board is the third  board if you start counting from the
left. The first is called write driver module, the second read amplifier and
the third servo control.
Normally the unit number is always shown on the display when the unit is in online mode


Good luck

Joop

-----Original Message-----
From: Gunther Schadow [mailto:gunther@aurora.regenstrief.org]
Sent: maandag 29 oktober 2001 7:18
Cc: classiccmp@classiccmp.org; port-vax@netbsd.org
Subject: TU81+ spooks (was: Re: first step getting VAX 6000-400 booted
...)


O.K. it would have been too good to be true. I got quite far with
my Ultrix, but then I got stuck with being unable to boot from
the TU81+ drive.

My VMS 5.4 does detect the TU81 just fine, calls it MUB0 and
allows me to mount it and write files to it. I think I have
now a bootable 9-track reel with at least the first 10
files of the Ultrix 4.1 bootable tape ready to go with all
blocksizes as required. It was fun writing!

But trying to boot this still brings up the old error:

 >>> SHOW ALL
...
   XBI D
   1+  DWMBA/B (2107) 000A
   2+  KLESI-B (0103) 0006
...
 >>> BOOT /XMI:D /BI:2 /R5:1008 MU0
Initializing system.
...
Loading system software.

?06 Halt instruction executed in kernel mode.
     PC     = 200D7264
     SAVPSL = 041F0600
     ISP    = 0003FBB8

?3D Error initializing I/O device

Bootstrap failed due to previous error.
 >>>

ans this goes all too fast certainly the tape never starts
moving before the error.

So I tried checking for the TU81's unit number (may be it's
MU1 or MU4 or MU213, who knows? First thing is when I power
up the TU81 it shows 000 on the front panel, but as soon
as it is initialized the display remains blank. So, perhaps
it has no unit number set at all?

The manual says in order to set the unit number you have to
go into TEST program 04. Which I did, TEST - STEP - STEP -
STEP - EXECUTE. But then it only says E77 and that's it.
This means, something is wrong, but what? The manual only
says to call DEC field service. I know the drive works
fine, the diagnostic test 01 has passed just fine and VMS
works happily with it. So, who knows about the TU81 and
how to set a unit number or make it bootable otherwise???

(PS: yes, I had the drive loaded and online when I tried
booting, did that offline mistake once before, but not here.)

thanks again for your excellent advice,
-Gunther