Re: Got DSM-11 running, any manuals online?

[Chris Zach via cctalk]

If so, then that's probably what the RQDX1/2 format *was*: Just a big 
bunch of 512 byte blocks, starting at zero and going up to the top.


The controller had to know the geometry of the drive in order to move 
the heads, know how many cylinders there were, etc. One thing I did 
notice is the last cylinder of the disk is not formatted like the others 
and throws a bunch of errors on the MFM_READ command on all tracks. It's 
possible that the controller checks there first, then consults the ROM 
based lookup tables to get the proper disk geometry. Which explains why 
some controllers supported RD51,52 and later ones supported the 53 but 
none supported the 54.


On the RQDX3 formatted disks, the first few tracks are also in a weird 
format, it's possible that is where the controller stores the 
head/cyl/sector format information. Note that a RQDX3 disk image does 
not seem to be able to connect up to the RQ driver like the RQDX2 one.


Interesting stuff. I'm guessing if you remove the first couple of tracks 
from the file one could then read the rest of the disk on SIMH (as the 
rest is probably just a big pile of blocks and that's all that matters 
to SIMH) unless there are remapped sectors in which case I have no idea 
how those would work.


Fun stuff.
C

On 1/8/2021 8:54 PM, Eric Smith via cctalk wrote:

On Fri, Jan 8, 2021 at 6:16 PM Chris Zach  wrote:


True, however SIMH has to write things to a "real" file that emulates
something of a disk.



I thought the SIMH representation of an MSCP disk was just a linear array
of 512-byte blocks, from block 0 to block n-1, in which case, it's still
not at all surprising that any RQDXn, or any other MSCP disk with the
standard Unibus/Qbus MSCP port interface would "just work".

If I'm wrong about how the disk is represented by SIMH, then maybe it could
be more surprising.

Re: Got DSM-11 running, any manuals online?

[Eric Smith via cctalk]

On Fri, Jan 8, 2021 at 6:17 PM Paul Koning  wrote:

> Yes, but also to hide bad blocks.  So the difference between a raw sector
> dump and a SIMH container file is, minimally, the spare sectors.  What that
> looks like depends on the format; I have no idea what MSCP controllers did.
>

MSCP controllers do the bad block mapping, so AFAIK the disk _always_ looks
to the host like a linear array 0..n-1 of 512-byte blocks.

When accessing an MSCP disk, the host should not, unless running special
diagnostics, be able to distinguish what kind of disk is in use, aside from
that it has a particular block count.

Re: Got DSM-11 running, any manuals online?

[Eric Smith via cctalk]

On Fri, Jan 8, 2021 at 6:16 PM Chris Zach  wrote:

> True, however SIMH has to write things to a "real" file that emulates
> something of a disk.
>

I thought the SIMH representation of an MSCP disk was just a linear array
of 512-byte blocks, from block 0 to block n-1, in which case, it's still
not at all surprising that any RQDXn, or any other MSCP disk with the
standard Unibus/Qbus MSCP port interface would "just work".

If I'm wrong about how the disk is represented by SIMH, then maybe it could
be more surprising.

Re: Got DSM-11 running, any manuals online?

[Chris Zach via cctalk]

A copy of the disk image is at

https://www.crystel.com/pdp/dsm-11.30.dsk

Feel free to put it on more stable archives. It appears to be a freshly 
genned system.


CZ

On 1/8/2021 1:16 PM, Sergio Pedraja wrote:

Any copy of this software available to play with?

Sergio

El vie., 8 ene. 2021 3:38, Chris Zach via cctalk > escribió:


Well, with Dave's help we got the DSM-11 disk to boot on SIMH. Oddly
enough SIMH seems to read a raw RQDX1/2 disk pretty well.

sim> attach rq0 dsm.dsk
sim> set cpu 11/73,1m
Disabling RK
Disabling HK
Disabling TM
sim> boot rq0

Booting DSM-11...

DSM-11 Version 3.0A
Now running the baseline system.

:1 G ^STU
Exit

DSM-11 Version 3.0A Device #1 UCI:
Exit

DSM-11 Version 3.0A Device #1 UCI: ?
:0
Exit

The problem is I don't remember how to use it anymore. Is there a
PDF of
the DSM-11 manual anywhere? I think this was a clean install, but I'd
like to check it for data before putting it into archives.

Also which archive would be best for it?

CZ

Re: Got DSM-11 running, any manuals online?

[Paul Koning via cctalk]

> On Jan 8, 2021, at 2:57 PM, Eric Smith via cctalk  
> wrote:
> 
> On Thu, Jan 7, 2021 at 7:38 PM Chris Zach via cctalk 
> wrote:
> 
>> Oddly enough SIMH seems to read a raw RQDX1/2 disk pretty well.
>> 
> 
> That's good to know, but not really all that odd. Arguably the main purpose
> of MSCP was to abstract away drive and controller differences.

Yes, but also to hide bad blocks.  So the difference between a raw sector dump 
and a SIMH container file is, minimally, the spare sectors.  What that looks 
like depends on the format; I have no idea what MSCP controllers did.

paul

Re: Got DSM-11 running, any manuals online?

[Chris Zach via cctalk]

True, however SIMH has to write things to a "real" file that emulates 
something of a disk. In this case I'm guessing it writes more as a super 
powered RQDX2 in that the first cylinders do not have the disk 
parameters and other odd stuff.


Which makes sense as the RQDX1 and 2 are simpler devices than the 3.

But as Dave pointed out, the last track on the disk is probably the bad 
block revector table. So no clue as to how the disk remaps bad blocks, 
but I don't think any of them were bad.


I'll put the image up on iguana tonight. If it's a blank system then 
someone can fiddle around with it a bit.


CZ


On 1/8/2021 2:57 PM, Eric Smith wrote:
On Thu, Jan 7, 2021 at 7:38 PM Chris Zach via cctalk 
mailto:cctalk@classiccmp.org>> wrote:


Oddly enough SIMH seems to read a raw RQDX1/2 disk pretty well.


That's good to know, but not really all that odd. Arguably the main 
purpose of MSCP was to abstract away drive and controller differences.

Re: M688 Flip Chip Unibus Power Fail Driver Modules

[Steve Malikoff via cctalk]

Noel said
>  (I said)   > There is an 11/15
>
> ??? Is that a typo for 'PDP-15'? The -11/15 looks just like an -11/20
>
>   https://www.ricomputermuseum.org/collections-gallery/equipment/dec-pdp-1115
>
> except it only has 16 address switches, not 18 as on the /20. (The front panel
> shown there has an OEM-specific re-paint; I couldn't quickly turn up an image
> of a DEC /15 front panel.)


Yes it was a typo sorry. I had meant to type 'PDP-15' but in my haste and 
having '11/15'
on the brain (owing to the FOX 2 I have) I mistakenly typed that instead.

Off-topic for this thread I guess, but, the FOX 2 has a two-tone green panel 
that are in the
Foxboro corporate colours, these being different shades to the Lab(?) 11/20 on 
the wiki page.
(Photo showing some of the FOX 2 switches at
http://www.vcfed.org/forum/showthread.php?76489-reproduction-PDP-8e-toggle-switches/page2
 )
If anyone ever sees a DECwriter in green then that would likely be a Foxboro 
one as well.

I've also seen on eBay a front panel from a russian 11/15 clone, quite a crude 
manufacture.

Re: Got DSM-11 running, any manuals online?

[John Forecast via cctalk]

A slightly newer version (3.3) is available from 
bitsaver.org/bits/DEC/pdp11/dsm-11 

  John.


> On Jan 8, 2021, at 1:16 PM, Sergio Pedraja via cctalk  
> wrote:
> 
> Any copy of this software available to play with?
> 
> Sergio
> 
> El vie., 8 ene. 2021 3:38, Chris Zach via cctalk 
> escribió:
> 
>> Well, with Dave's help we got the DSM-11 disk to boot on SIMH. Oddly
>> enough SIMH seems to read a raw RQDX1/2 disk pretty well.
>> 
>> sim> attach rq0 dsm.dsk
>> sim> set cpu 11/73,1m
>> Disabling RK
>> Disabling HK
>> Disabling TM
>> sim> boot rq0
>> 
>> Booting DSM-11...
>> 
>> DSM-11 Version 3.0A
>> Now running the baseline system.
>> 
>> :1 G ^STU
>> Exit
>> 
>> DSM-11 Version 3.0A Device #1 UCI:
>> Exit
>> 
>> DSM-11 Version 3.0A Device #1 UCI: ?
>> :0
>> Exit
>> 
>> The problem is I don't remember how to use it anymore. Is there a PDF of
>> the DSM-11 manual anywhere? I think this was a clean install, but I'd
>> like to check it for data before putting it into archives.
>> 
>> Also which archive would be best for it?
>> 
>> CZ
>> 

Re: Got DSM-11 running, any manuals online?

[Eric Smith via cctalk]

On Thu, Jan 7, 2021 at 7:38 PM Chris Zach via cctalk 
wrote:

> Oddly enough SIMH seems to read a raw RQDX1/2 disk pretty well.
>

That's good to know, but not really all that odd. Arguably the main purpose
of MSCP was to abstract away drive and controller differences.

Re: Got DSM-11 running, any manuals online?

[Sergio Pedraja via cctalk]

Any copy of this software available to play with?

Sergio

El vie., 8 ene. 2021 3:38, Chris Zach via cctalk 
escribió:

> Well, with Dave's help we got the DSM-11 disk to boot on SIMH. Oddly
> enough SIMH seems to read a raw RQDX1/2 disk pretty well.
>
> sim> attach rq0 dsm.dsk
> sim> set cpu 11/73,1m
> Disabling RK
> Disabling HK
> Disabling TM
> sim> boot rq0
>
> Booting DSM-11...
>
> DSM-11 Version 3.0A
> Now running the baseline system.
>
> :1 G ^STU
> Exit
>
> DSM-11 Version 3.0A Device #1 UCI:
> Exit
>
> DSM-11 Version 3.0A Device #1 UCI: ?
> :0
> Exit
>
> The problem is I don't remember how to use it anymore. Is there a PDF of
> the DSM-11 manual anywhere? I think this was a clean install, but I'd
> like to check it for data before putting it into archives.
>
> Also which archive would be best for it?
>
> CZ
>

Re: Got DSM-11 running, any manuals online?

[Paul Koning via cctalk]

> On Jan 7, 2021, at 9:38 PM, Chris Zach via cctalk  
> wrote:
> 
> Well, with Dave's help we got the DSM-11 disk to boot on SIMH. Oddly enough 
> SIMH seems to read a raw RQDX1/2 disk pretty well.
> 
> ...
> 
> The problem is I don't remember how to use it anymore. Is there a PDF of the 
> DSM-11 manual anywhere? I think this was a clean install, but I'd like to 
> check it for data before putting it into archives.

Neat.

I know nothing about DSM-11 other than the name, and the fact it was the OS on 
top of which ASSIST-11 was implemented.

Some googling turns up this http://www.ps8computing.co.uk/dsm-11.html which is 
modestly helpful.  
And this: https://kevinmurrell.tripod.com/dsm-11.htm
And this: 
http://h30266.www3.hpe.com/MasterIndex/installation_guide/installation_guide_0095de04.txt
 which suggests that semi-useful manuals might be found in the VMS 
documentation set, possibly under the name "Digital Standard M" rather than 
"...MUMPS".

paul

Re: M688 Flip Chip Unibus Power Fail Driver Modules

[Noel Chiappa via cctalk]

 > From: Steven Malikoff

 > Would that be part of this system at a Japanese computer museum? ...
 > the 11/05 has 'Unichannel15' on it

Yes, the 3 bays in the center are a PDP-15. (The indicator panel at the top
of the center bay is the one for the PDP-15 CPU; you can see it here:

  http://ana-3.lcs.mit.edu/~jnc/tech/DECIndicatorPanels.html

at the top of the 'PDP-15' section.) The Unichannel 15:

  https://gunkies.org/wiki/UNICHANNEL_15_System

is undoubtly there to drive the RK05; I don't think there's a native PDP-15
controller for that.


> There is an 11/15

??? Is that a typo for 'PDP-15'? The -11/15 looks just like an -11/20

  https://www.ricomputermuseum.org/collections-gallery/equipment/dec-pdp-1115

except it only has 16 address switches, not 18 as on the /20. (The front panel
shown there has an OEM-specific re-paint; I couldn't quickly turn up an image
of a DEC /15 front panel.)

Noel