Dec DMX11--What was it?

[Chris Zach via cctalk]

Anyone know about the Dec DMX11? It was apparently a 64 serial line Mux 
that plugged into pdp11 Unibus systems and had a fair amount of both 
intelligence and insanity on board. Reason is I'm looking into some old 
documentation about late 1970's Tote systems for Asian race tracks and 
the system they were building was beyond astronomical in terms of insanity.


(As in an 8 way pdp11/70 system cluster, with 11/04's running these 
DMX11's to hundreds of terminals)

Re: Looking for info on memory

[Nigel Johnson Ham via cctalk]

I feel such an idiot! I had minicom set for hardware flow control on the
PC that was connected as the console :-)

I'm sure I remember that as a symptom of no bank 0 memory!

Years ago it would have been the first thing I checked, well maybe not,
I would have had a real VT100 to connect to it. I am getting old!

Now I start adding modules, thanks for all who made suggestions!

cheers,

Nigel


On 2021-10-23 4:47 p.m., Noel Chiappa wrote:
> > From: Nigel Johnson Ham
>
> > an 11/23 will not work without bank zero memory
>
> It depends on what you mean by 'work'. If you mean 'ODT does not operate
> correctly', or 'the CPU won't run', I can assure you that neither of those
> is correct.
>
> Here is a recorded log from a session earlier today on a system here next to
> my desktop: it contains a KDF11-A (in slot 1Left of a Q-Q backplane)
> and a console DLV11-J (in slot 1Right), and no other cards:
>
>   ^@^@
>   00
>   @777560/00
>   @777564/00
>   777566/00
>   777570/?
>   @777640/17 777
>   @/000777
>   @777640G
>   Cmd:
>
>   177640
>   @^@^@
>
> As you can see, ODT is working,and the console registers are all responding
> OK.
>
> The thing at the bottom is that hack of putting a small program in the PARs
> (UIPAR0, in this case). The "Cmd:" prompt is where I told my console program
> to send a 'break' down the serial line to the -11, stopping the CPU. (The
> 'run' light had been on, after the "777640G".)
>
> (Note: The PAR hack doesn't work in J-11 CPUs; they won't do instruction
> fetches from PARs.)
>
> To confirm that I'm not BSing you, can someone else on the list
> please do this on their KDF11-A, and confirm that it produces the results
> I show about? Thanks.
>
>
> > All I get is output of 173000 and the no ability to input.
>
> If that's with just a non-LSI11 CPU card and the console serial line, the
> machine has a problem. As you can see above (the "777560/", etc were my
> type-in), you should be able to talk to ODT on a KDF11 (and I tried a
> KDJ11 yesterday, it worked too).
>
> (I don't recall if the LSI-11 types _anything_ when started with no working
> memory at 0; if anyone wants to know, I can fairly easily try it, I have a
> bunch of working LDI-11's, both quad and dual cards).
>
>   Noel

Re: Apple I auction

[Ethan O'Toole via cctalk]

Terrible in this day and age.


 >> That buyer's premium seems crazy steep. >

It is not.

--
Will



--
: Ethan O'Toole

Re: Apple I auction

[William Donzelli via cctalk]

> That buyer's premium seems crazy steep.

It is not.

--
Will

Re: Apple I auction

[Ethan O'Toole via cctalk]

That buyer's premium seems crazy steep.



Another Apple I on the auction block:

https://www.liveauctioneers.com/item/114629733_the-chaffey-college-apple-1-personal-computer


Steve




--
: Ethan O'Toole

Re: Looking for info on memory

[Noel Chiappa via cctalk]

> From: Nigel Johnson Ham

> an 11/23 will not work without bank zero memory

It depends on what you mean by 'work'. If you mean 'ODT does not operate
correctly', or 'the CPU won't run', I can assure you that neither of those
is correct.

Here is a recorded log from a session earlier today on a system here next to
my desktop: it contains a KDF11-A (in slot 1Left of a Q-Q backplane)
and a console DLV11-J (in slot 1Right), and no other cards:

  ^@^@
  00
  @777560/00
  @777564/00
  777566/00
  777570/?
  @777640/17 777
  @/000777
  @777640G
  Cmd:

  177640
  @^@^@

As you can see, ODT is working,and the console registers are all responding
OK.

The thing at the bottom is that hack of putting a small program in the PARs
(UIPAR0, in this case). The "Cmd:" prompt is where I told my console program
to send a 'break' down the serial line to the -11, stopping the CPU. (The
'run' light had been on, after the "777640G".)

(Note: The PAR hack doesn't work in J-11 CPUs; they won't do instruction
fetches from PARs.)

To confirm that I'm not BSing you, can someone else on the list
please do this on their KDF11-A, and confirm that it produces the results
I show about? Thanks.


> All I get is output of 173000 and the no ability to input.

If that's with just a non-LSI11 CPU card and the console serial line, the
machine has a problem. As you can see above (the "777560/", etc were my
type-in), you should be able to talk to ODT on a KDF11 (and I tried a
KDJ11 yesterday, it worked too).

(I don't recall if the LSI-11 types _anything_ when started with no working
memory at 0; if anyone wants to know, I can fairly easily try it, I have a
bunch of working LDI-11's, both quad and dual cards).

Noel

Re: Looking for info on memory

[Nigel Johnson Ham via cctalk]

Thanks for the links, but I already have the config data, it was only
the engineering drawings that I lost after I left the DEC business!

The 11/23 you supplied was originally configured to power up through 24,
indicating it was used on a battery-backed-up system, so I changed that
one to go directly to ODT.  I got an 11/73 from another collector and
left that one to power up to 173000.

I know from years of experience as an FE and running a production line
that an 11/23 will not work without bank zero memory, hence the title of
this email chain.

So while I appreciate everybody's help, there is no point in scratching
your heads! If I cannot find any data on the Plessey memory I will just
have to look for an MSV11-DD or something to give me at least some
memory to start off with!

cheers,

Nigel



The 11/23 you supplied was

On 2021-10-23 1:34 p.m., Josh Dersch wrote:
> On Sat, Oct 23, 2021 at 10:30 AM Josh Dersch  > wrote:
>
>
>
> On Sat, Oct 23, 2021 at 10:12 AM Nigel Johnson Ham via cctalk
> mailto:cctalk@classiccmp.org>> wrote:
>
> It is not possible to get ODT running without bank 0 memory. 
> All I get
> is output of 173000 and the no ability to input.
>
>
> How is your CPU board configured?  Based on the above, it sounds
> like it's set up to jump to a ROM bootstrap at power-up (at
> 173000) and I'm guessing given your current configuration that
> there isn't one.  Without memory present/functional, this may be
> confusing things further.  There are jumpers on the 11/23 CPU to
> select what the CPU does at power-up (see:
> https://gunkies.org/wiki/KDJ11-A_CPU
> ).  Try setting it to drop
> directly into ODT instead.
>
>
> Sorry, just realized I pasted a link for the 11/73 CPU config (same
> basic idea, though).  Try this instead:
> http://www.willsworks.net/pdp-11/boards#KDF11-BA
> .
>
> - Josh
>  
>
>
> - Josh
>

Re: Looking for info on memory

[Josh Dersch via cctalk]

On Sat, Oct 23, 2021 at 10:30 AM Josh Dersch  wrote:

>
>
> On Sat, Oct 23, 2021 at 10:12 AM Nigel Johnson Ham via cctalk <
> cctalk@classiccmp.org> wrote:
>
>> It is not possible to get ODT running without bank 0 memory.  All I get
>> is output of 173000 and the no ability to input.
>>
>
> How is your CPU board configured?  Based on the above, it sounds like it's
> set up to jump to a ROM bootstrap at power-up (at 173000) and I'm guessing
> given your current configuration that there isn't one.  Without memory
> present/functional, this may be confusing things further.  There are
> jumpers on the 11/23 CPU to select what the CPU does at power-up (see:
> https://gunkies.org/wiki/KDJ11-A_CPU).  Try setting it to drop directly
> into ODT instead.
>

Sorry, just realized I pasted a link for the 11/73 CPU config (same basic
idea, though).  Try this instead:
http://www.willsworks.net/pdp-11/boards#KDF11-BA.

- Josh


>
> - Josh
>
>

Re: Looking for info on memory

[Josh Dersch via cctalk]

On Sat, Oct 23, 2021 at 10:12 AM Nigel Johnson Ham via cctalk <
cctalk@classiccmp.org> wrote:

> It is not possible to get ODT running without bank 0 memory.  All I get
> is output of 173000 and the no ability to input.
>

How is your CPU board configured?  Based on the above, it sounds like it's
set up to jump to a ROM bootstrap at power-up (at 173000) and I'm guessing
given your current configuration that there isn't one.  Without memory
present/functional, this may be confusing things further.  There are
jumpers on the 11/23 CPU to select what the CPU does at power-up (see:
https://gunkies.org/wiki/KDJ11-A_CPU).  Try setting it to drop directly
into ODT instead.

- Josh

Re: Looking for info on memory

[Nigel Johnson Ham via cctalk]

It is not possible to get ODT running without bank 0 memory.  All I get
is output of 173000 and the no ability to input.

cheers,

Nigel

On 2021-10-23 11:00 a.m., Noel Chiappa via cctalk wrote:
> > From: Nigel Johnson
>
> > I will wait with bated breath!
>
> First things first; did you get either/both CPU's running ODT OK
> in a system containing just i) the CPU card and ii) the console
> serial interface?
>
>   Noel

Re: Looking for info on memory

[Noel Chiappa via cctalk]

> From: Nigel Johnson

> I will wait with bated breath!

First things first; did you get either/both CPU's running ODT OK
in a system containing just i) the CPU card and ii) the console
serial interface?

Noel