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PDP 11/45, Part 2

HI All;
LOU, Thank You for Your Very KIND words !!!!
But, as You know, I still need to figure out, where the problem is Above Memory.. I am currently getting a Second set of Memory Boards and setting them up for the Rest of the Memory Space.. That way I can have the full 28K of memory, without Memory Management..
I have found some Boards and I knew about them, but didn't bother looking at what they were/are..
Would any of these help me with my Console SLU problem ??
I have the following Boards, I don't know IF they will work in slot 27 and that is the next issue, even If I can use them.. I would have to make significant Changes, If I have to add another BackPlane Board like a DD11-CK, I could use it in the chain, and that may be my next Re-Make, If I have to.. I would have to Lengthen All of the Power Wires for the Front Panel/Console and Make the Wooden Frame Longer as well..
M7867 DUP11DA
M7285 DJ11 Control Board (No Crystal)
(2 Each) M7819 8 line EIA ASYNCHRONOUS MUX Could I use this for One SLU ??
THANK YOU Marty
 
Hi All;
I just went to Our favorite place (BitSavers), and downloaded the Listing for much of the XXDP Diags for the PDP 11/45 and (I think) the M7800..
The Only way at this point for me to get it in is to use the Front Panel Switch Register.. There is a program to check out the General Purpose Registers, which depending on its length, I hope to Fat Finger in, and of course the M7800 program..
I forgot to mention I am interleaving the two Memory Boards.. Hopefully it will work..
It Looks like the Interleaving is working, Only Time will tell for sure..
THANK YOU Marty
 
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Hi All;
I have Fat Fingered in the "Basic Address Memory Test Down".. And it is Running Fine, Light Blinking all over the Place..
For some Reason I Could NOT get my Phone Camera to take more than 3 seconds of Video's.. I have it on the Charger, but Really I am not sure Why it is acting like this..
Next is "Basic Address Memory Test Up"..
It FAILS the upper Address test, I haven't narrowed it down, but its somewhere around the last 4 K or so of the 28K of Memory, which Might be related to Why the I/O fails as well.. And the Adrs Err Led is lit as well..
THANK YOU Marty
 
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Hi All;
I have taken out and turned upside down the BackPlane for the 11/45 looking for shorted and Bent pins.. I didn't find anything significant, I knew about some around the edges that had become bent over when I first put this in.. But they are all put back in place.. I also took a look at the Memory Board BackPlane and it was the same a few slightly bent pins, but nothing to worry about..
I am in the process according to the 11/45 Documentation of tying slots 26 and 27 sections A and B together, using Wire-Wrap wire so the UniBus "A" and UniBus "B" are tied together as one unit.. That will still allow me the Slots, without having anything plugged into them.. And free up one M930 terminator, since I won't need one in "A" and another in "B".. And I can then use all three slots "C-F" as SPC slots, and not worry about which Bus it is attached to..
I have wired half of what I need to wire.. And the last Picture is the finished product.. And here are a couple of pictures --

02082014001.jpg 02082014002.jpg 02082014003.jpg


THANK YOU Marty
 
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Hi All;
I got the Machine all back together, and it mostly works like it did before.. The Documentation says to Now plug things into Slot 28 instead of slot 26, But it doesn't see Memory at all in slot 28, but it does in slot 26 and 27.. So, just in case I terminated slot 28 like before and plugged in Memory back like it was in slot 26..
I took out the Second upper half of Memory that I had interleaved, and changed to a Different Timing Board, one that would start and '000000 and not be Interleaved.. I re-loaded the Address Test Up and I got Errors, starting at Bit 12 or 020000 which is in the 4 to 8 K range and with bits 12 and 13 Examined it shows in the Data just bit 12.. So I suspect a problem either in the Memory Addressing or in the UniBus.. This needs further checking..
THANK YOU Marty
 
Hi All;
I changed each of the Memory Modules one at a Time and it makes NO Difference, G114, H217C and G235..
I also found that If I Run the Address Program with the Top of memory at 4K, 017700, it will run Ok.. But If I run it at 8K, 037700, Not only do I get errors at bits 12 and 13, but it also Trashes out the first three Lines of Code and Puts something else there..
THANK YOU Marty
 
Hi All;
I am checking where the Address Bits 11 thru 17 go to..
As near as I can tell, by Ohming out they don't seem to go to any of the Processor Boards, But I will eventually check the Documentation.. They do go to the M787 (Clock Board) and I may have found some shorts, I scraped any area between traces that might affect it.. So far I have traced it to slot 16 which isn't used, and most likely slot 21, they both do the same thing.. Next I will check slots 26, 27 and 28, before going back to slots 17-20 and 22-25, and the terminator in slot 1..
THANK YOU Marty
 
Hi All;
Well, I put the Boards all back in to check if the M787 that I looked at and scrapped..
And The 11/45 all of a Sudden doesn't Work, it seems like it is Dead and No response from the Front Panel, except the Start Button..
The Data Leds are all on, and the Address Leds are all off.. Run and Kernal Leds are on, and when I press the Start Button the Run Led turns off and Master Led turns on.. But that is the Only response, from the Buttons..
THANK YOU Marty
 
Hi All;
I have some Good news and some Bad news..
First the Good news, I got the PDP 11/45 working again.. Here's what happened.. I had taken out all of the Boards and put then out of the way in my Bedroom and they were on some cardboard boxes and the pile slid and fell, I caught most of the Boards.. Fast forward to later, putting them all back in and it not working..
I Prayed to God for an answer, and Yesterday when getting up I had an answer, the Timing Board.. So, I have exchanged the Timing Board and it NOW Works !!! I Thank God for the Answer..
Now the Bad news, it still has the same problem as before, But looking closer at the output from the Addressing test.. I think I have a clue to what is happening.. When it addresses the various locations, Bit 13 is re-mapped to address 000000, and after bit 13, bit 14 is remapped to address 13 Area, and so on..So I am going to look at bit 13.. It might be stuck Low somewhere..
So now I have two Boards to Fix, the Other Timing Board and the other Data Paths Board..
THANK YOU Marty
 
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Hi All;
The Plot thickens, when I put the Memory Management Boards back in and re-run the tests.. Bit 9 is remapped to bit '000000 area.. Which might mean on my Memory Management Board possibly bit 9 is stuck low and possibly more.. But that has to be fixed First, and Bit 13 needs to be fixed on my SJB Board.. More than likely Bad Ic's.. I will need to get the scope going, and some Documentation as well..
THANK YOU Marty
 
Hi All;
I had a Bad 7439/8881 and that what was causing a problem with bit 13.. I tried another 7439 that I had and it was worse, so I put in a 7401, and Now bit 13 is OK, and now the Address Test is passing that point..
But now Bit 14 is showing up in bit 13's space.. So I need to look at bit 14..
THANK YOU Marty
 
Hi All;
I had replaced the 7439 with a 7401 and it looks like the 7401 Doesn't always have enough Oomph to Drive the following circuits.. I can try as I saw many Years ago on an old memory Board, where they Mounted two Ic's one on top of the other for more Drive Power.. The 7401 looks like it is about 1/4 of the Output of a 7439..
The other option that I have On This Board Only, since one output pin and one input pin are swapped, is try a 7438, its output is rated at about 48ma, against 20ma for the 7401 and 80ma for the 7439..
THANK YOU Marty
 
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Hi All;
The System is NOW Passing the Upper Address Test, up to 077700.. I put in two 7401's and wired them in Parallel..
Next is the additional Core Memory Boards, then
Next I will put in the M7856 and see If it sees it without an Address Error Led coming on..
THANK YOU Marty
 
Hi All;
It Passing with Full Memory, 28K !!!!! I will see IF I can Record a Video.. Otherwise Here is a picture..

02102014004.jpg

THANK YOU Marty
 
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Hi All;
Out of four Serial Boards, two M7800's and two M7856's, I have Only one!! that the computer sees at 177566 without an Address Error Led.. I am not sure at this point if the rest of the Board works..
THANK YOU Marty
 
Hi All;
I can get a Signal on Serial In, when I Type a 'key'.. But, No Serial out, on the UART.. And I am not sure What other signals it (the Uart) needs to pass the Signal on to the Serial Out pin..
Does Any One Know How to Put this Board (M7856) in Maintenance Mode ??
Its mentioned in the Documentation, But I can't find just HOW to do that..
THANK YOU Marty
 
Marty said:
Hi All;
I can get a Signal on Serial In, when I Type a 'key'.. But, No Serial out, on the UART.. And I am not sure What other signals it (the Uart) needs to pass the Signal on to the Serial Out pin..
Does Any One Know How to Put this Board (M7856) in Maintenance Mode ??
Its mentioned in the Documentation, But I can't find just HOW to do that..
THANK YOU Marty
Click to expand...

Refer to the DL11-W Operator's Manual (see: http://bitsavers.trailing-edge.com/pdf/dec/unibus/EK-DL11W-OP-001_May77.pdf on bitsaver's).

Top of p.29. Set bit<2> in the TX status register at 777564 to put the unit into maintenance loopback mode.

Don

For the cable wiring to the 40p connector you can refer to this manual as well. It has the connections documented, see table 2-10 on page 25 of the manual. Besides the input/output connections to your RS232 cable, you also have to have a pin-pin jumper (pin M to pin E) that inserts the EIA level shifter logic in the receive signal path. You can why on the schematic page 10 (see: http://bitsavers.trailing-edge.com/pdf/dec/unibus/MP00106_DL11-W_Aug77.pdf )
 
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Hi All;
THANK YOU Don !!!!
I got the Cable wired already..
And After setting up my M9301, and seeing some response from the Scope.. And not sure what I was getting on 110 Baud..
I switched the setting to 9600 Baud, I set the Address to 173000 and did an Examine, then hit Start.. And,
Behold I got 177777 177773 177777 177777
$
I think I got the M7856 Working !!!!!!!
Now that (I think) I got that I am unsure of what and How to do next.. I need to find out How to use it in this mode.. So I can download things like XXDP, and such..
THANK YOU Marty
 
Hi All;
IT WORKS !!!!!!!!!!!!!!!!!!!!!!!!
I was able to enter the Echo Program Via the Emulating Console and then I went and check it with the Switch Register and all was correct.. And
then I was able to run the Echo program and it Worked like a charm..
I found out How to Enter thing via the Emulating Console by looking at the Manual for the M9301.. THANK YOU, BITSAVERS !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
I can Say that NOW I have a Fully Functioning PDP 11/45 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Now to get a couple of Large Box Fans to mount on the side of the Box Frame to keep the CPU Boards and the Memory Boards COOL ..
THANK YOU Marty
 
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