On Tue, 25 Nov 2003, Mr Ian Primus wrote:
> Well, the three tapes I tried must not have been
> bootable (or at least not directly bootable) I do have
> one more tape, that does seem to be a BRU tape. I
> booted it, and it did more. It loaded for longer, then
> crashed. Woohoo! It's working well enough to crash! (I
> think this is an improvement). When it crashed, it
> gave me this:
>
> SYSTEM CRASH AT LOCATION 011336
> REGISTERS
> R0=000304 R1=172522 R2=063107 R3=172520
> R4=000010 R5=000000 SP=117756 PS=000010
>
> SYSTEM STACK DUMP
> LOCATION CONTENTS
> 117756 000004
>
> 004412
> _at_
OK. R3 is pointint at 172520, which is the MSCP DISK
controller address (KDA50,UDA50,RQDX, etc.) It probably
decided to bail out after finding no usable disk controllers.
> I don't know off the top of my what model tape
> controller I'm using. I'll have to check when I get
> back home tonight. I know it's an Emulex, but that
> really doesn't help. <grin>
It doesnt :) When doing remote debugging, I usually wanna
know what I am dealing with, for both disk and tape controllers.
> > File 0 : blocksize 512 (439 blocks)
> OK, so I guess that File 0 is what I'm currently
> reading, correct? Is this the part of the tape that
> has that error message in it?
Yup. The ROM (or your boot routine) read the first (sometimes
second) block of that, which in turn goes to read the rest.
> Well, it looks like I'll be trying to write a tape
> tonight. I'll have to connect the Prime's SCSI tape
> drive to a PC, I should just be able to dd a tape
> image to the tape device without any problems, right?
Yup. Well, hmm. PDP-11 boot tape usually have a number
of "files" on them, and each "file" can use more than one
block size- see my example. You can't just dd it to a
file, and then from a file back to tape.
> Or will I have to write it in segments, specifying the
> block size as I go? I haven't done a lot with tape
Yep.
> formats before. Also, once I figure out which tape
> controller I am using, how do I write a compatible
> tape from *nix?
No worries, the tape stuf seems to be fine now, we probably
have to concentrate on the disk part now.
--f
--
Fred N. van Kempen, DEC (Digital Equipment Corporation) Collector/Archivist
Visit the VAXlab Project at http://www.pdp11.nl/VAXlab/
Visit the Archives at http://www.pdp11.nl/
Email: waltje_at_pdp11.nl BUSSUM, THE NETHERLANDS / Sunnyvale, CA, USA
Received on Tue Nov 25 2003 - 08:53:46 GMT