Looking for info on memory

[Nigel Johnson Ham]

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 <derschjo at gmail.com
> <mailto:derschjo at gmail.com>> wrote:
>
>
>
>     On Sat, Oct 23, 2021 at 10:12 AM Nigel Johnson Ham via cctalk
>     <cctalk at classiccmp.org <mailto:cctalk at 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
>     <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
> <http://www.willsworks.net/pdp-11/boards#KDF11-BA>.
>
> - Josh
>  
>
>
>     - Josh
>