DEC RQZX1 and KDJ11-E boot problem? - test-drb@ccmp.vtda.org

13 Jun 2010

All right. Time to clear up some misconceptions, I see... :-)

Nigel Williams <nigel.d.williams at gmail.com> wrote:

...
  On Sun, Jun 13, 2010 at 3:11 AM, Zane H. Healy
<healyzh at aracnet.com> wrote:
  Of course you may simply have some sort of
hardware issue going on there as
 well, I'm not familiar with the RQZX1.  
 The drives passes the built-in RQZX1 diagnostics, which includes
 read/write/verify tests etc. I formatted the SCSI drive via the RQZX1
 too (prior to using the drive on Linux via SIMH to install RSTS/E),
 just in case the format process was doing something special (although
 I can't imagine what since I understand MSCP masks drive specifics). 
Well, when you format the drive on the RQZX1, the controller might put 
down some special information on the disk.
But once you move that drive over to your PC, you are no longer talking 
MSCP, nor are you aware of any special areas set aside by the RQZX1, so 
you will most likely overwrite any such information making the 
formatting pointless.
Ie, if the RQZX1 is putting some special information on the disk during 
the formatting, you cannot then take the drive to some other system and 
connect and use it there expecting things to not become messed up.

However, if the RQZX1 does not put down any special information on the 
disk, what you do should work fine. But in that case, a formatting will 
not make any difference either.

MSCP in a way do more than just "mask drive specifics".

I don't have my RQZX1 manuals anywhere near, so I can't say more about 
any RQZX1 specific things. Sorry...

...
  A next posible step is to use this source-code for a
MSCP boot so I
 can catch the initial boot load and see what is in the first disk
 block (containing the next level bootstrap):

 http://www.slowdeath.com/AK6DN/PDP-11/M9312/23-767A9/23-767A9.lst 
I doubt that will help. I suspect that it is the controller which just 
throws an error back at the boot code when it tries to read the boot 
block. So nothing will be read.

...
  I will also try a different model of SCSI drive too -
perhaps the
 Quantum Fireball is too much of a good thing (4200RPM 2.1GB); I have
 an old clunker of a Quantum ProDrive 80S (3600 RPM 80MB!)

 Does anyone know how SCSI ID's are mapped to MSCP LUNs? so far the
 RQZX1 appears to map the first SCSI ID (in my case #4) to LUN 0 (which
 is what I want) - I am assuming it just does them in sequence. 
I would have thought that SCSI id #0 should map to LUN 0. #4 have 
traditionally been reserved for tapes (or was that CD?), although that 
could also have been #5 or #6.

	Johnny