Revive 11/34

Jerry Weiss jsw at ieee.org
Fri Dec 8 20:58:08 CST 2017


> On 12/8/2017 3:50 PM, Jerry Weiss wrote:
>> On Dec 8, 2017, at 2:25 PM, John Welch via cctech <cctech at classiccmp.org>
>>  wrote:
>> 
>>> I am reviving an 11/34. Cards are:
>>> 
>>> Back/Fans [M8266--------]  Front of machine where keypad is.
>>>           [M8265--------]
>>>           [M9312] [M7859]
>>>           [M7762--------]
>>>           [OPEN]  [M7860]
>>>           [M7840--------]
>>>           Bus grant in third from front slot
>>>           [M9302] [M7856]
>>> The 7856 is hooked to a cable/null modem (i think)/PC running XP&Hyperterminal
>>> 
>>> When I first powered on the programmers console said '7' and I powered off, then back on, and now it says '5'
>>> 
>>> Any suggestions as to what to try first?  I may have the bus grant in backwards.  I have other boards I can try.
>>> 
>>> Sincerely,
>>> John Welch
>>> :qw
>>> 
>> 
>> 1) The G727A bus grant card is keyed (somewhat).     It should be in Row D (fourth from the back)
>>      It won’t seat evenly if reversed. At least that is what my scraped knuckles remember.     
>> 
>>      You can temporarily pull it out to finish the check out.  There’s nothing past the 
>>       M7840 that requires DMA.

Ignore this last suggestion (see below).

>> 
>> 2) Check the baud rate, stop bits and parity settings on both the Hyperterminal and the M785 to make sure they match. 
>>      
>> 3)  Are you seeing a single 7 or 5 on  KY11-LB Programmer Console or on the Hyperterminal?
>>  
>>      An other status led’s lit on the KY11-LB?
>> 
>> 4) I don’t see any memory listed…  Do you have any M7847’s?  
>> 
>> 5) Grab a copy of EK-11034-UG-001 PDP-11-34 System User’s Manual for more info.
>> 
>> 
>> Jerry
>> 
>> 
> 
> 
> On Dec 8, 2017, at 5:26 PM, John Welch via cctech <cctech at classiccmp.org> wrote:
> 
> Update:
> This is the map of the machine:
> 
> ........................   AAA BBB CCC DDD EEE FFF ....................
> (Rear/Fans/Power Supply) 1 [M8266----------------] (Front/Keypad/DC ON)
> ........................ 2 [M8265----------------] ....................
> ........................ 3 [M9312] [M7859--------] ....................
> ........................ 4 [M7891----------------] ....................
> ........................ 5 [M7762----------------] ....................
> ........................ 6         [M7860--------] ....................
> ........................ 7 [M7840----------------] ....................
> ........................ 8             GNT ....................
> ........................ 9 [M9302] [M7856--------] ....................
> ........................   AAA BBB CCC DDD EEE FFF ....................
> Reseating the ribbon cable on the M7859 changed the display.  I have replaced the M7840 with a G7273.
> Now when I power on it says (dim)0, (bright)0, blank, (dim)0, blank, blank.
> I have reseated the M7859, I don't think I have another one.
> Maybe I should hit it with a vacuum.
> I had forgotten about needing to cut a wire for DMA.  Can you give me a refresher on how to tell which slots are cut?  I remember having to turn the chassis over and looking for a particular wire but that was >15 years ago.

Your update has a M7891 (MS11) which addresses the memory questions.

The Programmers Console display is not correct.  It should be 7 digits, either 0000000 when running or some other data or address value.
Check the cable orientation.  see http://bitsavers.informatik.uni-stuttgart.de/pdf/dec/pdp11/1134/KY11-LB_MaintMan.pdf <http://bitsavers.informatik.uni-stuttgart.de/pdf/dec/pdp11/1134/KY11-LB_MaintMan.pdf> chapter 9.

A light cleaning and reseating all the boards is an easy place to start.

For NPG changes see http://bitsavers.informatik.uni-stuttgart.de/pdf/dec/pdp11/1134/1134_UsersManual.pdf <http://bitsavers.informatik.uni-stuttgart.de/pdf/dec/pdp11/1134/1134_UsersManual.pdf> section 4.2.2.2

Ignore my earlier comment about leaving out the G727a.  I had slipped into QBUS thinking mode in error.



> On Dec 8, 2017, at 5:49 PM, John Welch <jcwelch at hal-pc.org> wrote:
> 
> I also have an 11/04 that I went and drug out.  It is configured like this:
> 
> 11/04:
> ........................   AAA BBB CCC DDD EEE FFF  ....................
> (Rear/Fans/Power Supply) 1 [M7263----------------]  (Front/Keypad/DC ON)
> ........................ 2 [M7847----------------]  ....................
> ........................ 3         [M7859--------]  ....................
> ........................ 4 [M7847----------------]  ....................
> ........................ 5             GNT          ....................
> ........................ 6 [M7762----------------]  ....................
> ........................ 7 [M7840----------------]  ....................
> ........................ 8         [DILOG--------]  ....................
> ........................ 9       {nothing}          ....................
> ........................   AAA BBB CCC DDD EEE FFF  ....................
> I am thinking I could put a M9203/M7856 into slot 9, and find a M9312 for slot 3 and maybe this would fire up.  Any suggestions?

The 11/04 and 11/34a are of the same engineering cycle, so share these parts.  See http://www.pdp-11.nl/pdp11-34a/cpu/options/bootstrap-info.html <http://www.pdp-11.nl/pdp11-34a/cpu/options/bootstrap-info.html> 

and

http://www.bitsavers.org/www.computer.museum.uq.edu.au/pdf/EK-11004-OP-001%20PDP-11-04%20System%20User%27s%20Manual.pdf <http://www.bitsavers.org/www.computer.museum.uq.edu.au/pdf/EK-11004-OP-001%20PDP-11-04%20System%20User's%20Manual.pdf>

I believe the cabling for the M7859 is a little different between the two  See Section A in the 11/04 Manual.

Jerry







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