early PDP-11/45 info sought

[Jay Jaeger]

On 1/27/2019 11:01 PM, Fritz Mueller via cctalk wrote:
> Hi Jay,
> 
>> On Jan 27, 2019, at 7:07 PM, Jay Jaeger <cube1 at charter.net> wrote:
>>
>> I think I can help some... I DO have earlier PDP-11/45 CPU drawings...
> 
> Man, this list is the absolute best!
> 
> The '72 KB11-A drawings would be most immediately useful.  If you only have time for a subset of pages, I would find the schematics for M8100, M8103, M8105, and M8106 particularly interesting.  
> 
> It would also be interesting to compare the M8103 ROM listings between the '72 and '74 drawing sets and see whether they snuck in any microcode changes/fixes.

Will start scanning today.

> 
> I do have KT11-C and FP11-B in my system, but haven't checked their provenance yet.  To the extent that I've had to repair these, anyway, they've matched the drawings that I do have.
> 
>> I have a PDP-11/45 From U. Wisc. ECE that claims to be S/N 1525
> 
> Wow, another <2000 11/45!  Do you have yours up and running?  Do have its ECO history?  I found one other oddity during my restore that seems related to early 11/45's -- no +15V to pin CU1 in SPC slots 26-28, which keeps any EIA DL11 from working correctly in those slots (though the contemporary 20ma DL11-A would work).  I have a feeling this might have been addressed in a later ECO.  It would be interesting to check this on your backplane?
> 

My 11/45 has not been on for a lonnnng time.  Some time ago I had it on,
it could sometimes boot RT-11, but failed MUL diagnostics - but I was
not confident that the diagnostic itself was correct.

I will see if I can check on the +15V issue (hopefully without having to
turn the thing on) - I don't have a real TTY for it to talk to, so it
isn't something I would have noticed.

> Thanks for taking a look through your library, and for the generous offer to take the time to do some scans.
> 
>    cheers,
>      --FritzM.
> 
> 
> 

Not a problem.  Fortunately, when I migrated to my new PC this winter, I
had the foresight to test my scanner - which did NOT work because the
TWAIN drivers for it (a Ricoh IS300e) would no longer install, and
installed a virtualbox VM running Windows 7 to talk with it.

JRJ