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PDP 11/45, Part 4

Marty

Veteran Member
Joined
Jul 26, 2009
Messages
3,141
Location
Boulder , Colorado USA
Hi All;

It's that time of Year again..

I am going to get out the PDP 11/45, and see what I can do for it..

And it's not that the PDP 8i clone hasn't been fun.. And alot of learning experience..
I will put the -8 away for awhile, but there is more for me to do on it..
I have notebooks to finish and update and a second TTY port to wire up..
And this is the longest that I have worked on any one project, I think..

I'm just itching to get back to the /45..
One of the things that I am going to do right off is used Deoxit on the MotherBoard, I don't have any Deoxit Gold, so I can't use that at present, But, sometime I will get some for the Boards..

Here is the Link for the previous posting..
http://www.vintage-computer.com/vcforum/showthread.php?44623-PDP-11-45-Part-3/page14

Here is a picture of the PDP 11/45 for those here who have not been apart of my previous Adventures..

002.jpg 907.jpg

The second picture is one of my Old pictures..


THANK YOU Marty
 
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Marty,

Give me a bit of time to 'catch up' with parts 1 to 3...

Can you just give me a very quick run-down of where you are with the beast (just in case I miss something significant)?

My wife has got me doing 'something else more important' at the moment (if you get my drift). Should be finished by the weekend with any luck.

Dave
 
Hi All;

Thank You, Dave for Your letting me know where You are in this..

"" Give me a bit of time to 'catch up' with parts 1 to 3...

Actually, for Now all You need to look at is Part 3..

Can you just give me a very quick run-down of where you are with the beast (just in case I miss something significant)? ""

It is Not working at Present, I forgot the name and Board number, But once I get them in, I will be able to tell where I think the Problem may be..
This machine has been working and then Not working many times.. Mainly due to my Mistakes..

Here is a picture of most of the PDP 11 Boards.. Not all of these are for the 11/45.. But, most of them are for it..

003.jpg 004.jpg

The Second Picture is what it looks like Now, and it does Not work at present, just like I thought..

THANK YOU Marty
 
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Is there a page with a rundown of the cards installed, the power supply and regulators, backplane, and enclosure box model?
b
 
Hi All;

Bill, Thank You for Your Question..

"" Is there a page with a rundown of the cards installed, the power supply and regulators, backplane, and enclosure box model? ""

Yes, I will need to go look for it on BitSavers, as I have my information from the Schematic(s) and Papers that I got with mine..

http://bitsavers.trailing-edge.com/pdf/dec/pdp11/1145/1145_System_Engineering_Drawings_Jun74.pdf

See page 11 for Board assignment, and page 122 and following on Power Supply information..

THANK YOU Marty
 
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Hi All;

M-Thompson, Thank You for the Pictures and Board Layout.. They look Great..

The only thing I would add is that, on some systems like mine..
There are some differences..
If You do not have the Memory Management Cards in slots 13 and 14..
Then slot 13 is left open, and slot 14 has the SJB (8116) in there in stead..
I had to wire-wrap my own SJB Board..

THANK YOU Marty
 
Hi All;

Looking at the Timing Card last night, and getting nothing, got me to thinking.. And so during the night..
I had a memory and hopefully not a false memory..

But, before when I blew up the I/O Card, it caused among other things a loss of Timing, no front panel response and most importantly no - 12 Volts on the Front Panel..

And it is doing the same thing at present.. So, I am going to check my +/- 12 volt power supplies..
And hopefully that will (once it's fixed) make things work somewhat better.. If that is the problem..
No, That's not it, I have Both + and - 12 volts..

I found another problem that I fixed, the Timing board +12 wasn't connected..
It made no difference otherwise.. So it looks like I will go another level deeper..

THANK YOU Marty
 
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Have you looked on the TIG board to see if the 33MHz TIGB XTAL H, TIGB SOURCE CLOCK L, TIGB CLOCK L, and TIGB CLOCK H signals are active?

Do you have maintenance cards for this system?
 
Hi All;

M-Thompson, You anticipated what I have been working on this morning..

"" Have you looked on the TIG board to see if the 33MHz TIGB XTAL H, TIGB SOURCE CLOCK L,
I just got this signal E32, pin 8 to Output, that I hadn't had before.. And Yes, it's at 33MHZ..
TIGB CLOCK L, and TIGB CLOCK H signals are active?
I hadn't had a chance to look at these signals yet, But, I am going to do so Next..
Yes, they are there..

I am working my way thru the Count-down chain on page 2.. E13, pin 8 has no output, so I am investigating this..
I have started a PDP 11/45 NoteBook..

Do you have maintenance cards for this system? ""

Have You forgotten the thing that I wire-wrapped on that Blue handled Board, that everyone chided me about wiring on the wrong side.. My maintenance card..

THANK YOU Marty
 
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I am working my way thru the Count-down chain on page 2.. E13, pin 8 has no output, so I am investigating this..

Take a look at section 8.8.5 in the KB11-A,D Central Processor Unit Maintenance Manual. It describes the behavior of the TIGA STOP T1 L signal that comes out of pin 8 of E13. It looks like most of the time this signal should be high.

If pins 2,3,9 and 10 are high pin 8 will be low or if pins 1,4,5,6,11,12 and 13 are high pin 8 will be low.

If the processor is running you should see activity on the 0 and 1 outputs of the T* flip-flops.
 
Hi All;

M-Thompson, Thank You for Your Description and Information..

BUT, You wouldn't guess, what the problem Was..

I had the Cables to the front Panel in the correct place.. Only I had them Backwards A Connected to VV and so forth..
I found it while Pulsing the Bit 0 on the SJB Board and Bit 0 on the display was Not Blinking..
So I took off the Front Panel Plastic Cover And followed the Stripe on the Cable, and found the Mistake..

Right now I have Memory, But NO Serial I/O Card.. I have to find/ determine which of the many that I have is good, And I don't want to Just plug them in, I have been down that Road Before, with the PDP 11/40, Which is what wiped it Out for Good.. Burned some Traces out..

THANK YOU Marty
 
Hi All;

M-Thompson, Thank You for Your Suggestion..

"" Did you try some simple toggle-in programs to see if the processor works? ""

I am looking for some of my old Programs, I tried the chase program, but it runs too fast to see if it is really running..
What I would like is a Binary Counting program, I just can't find it at present..

Any Programs (small), I would welcome them and I will try them..

THANK YOU Marty
 
Hi All;

Jack, Thank You for the Link and Information..

I had forgotten about this page, Somewhere I have a copy of this page on Paper..
I can and will do many of the Programs/Tests in the morning..
I tried the two Looping programs, they work Just fine..
The Memory Sizing program also works..
The Memory Addressing, stopped at one of the Instructions in the Program..
Which could have been an error in my entering of the program, a Bad Memory Board, or something else..
I will Investigate later..
I found the programming book by Lawrence, but I didn't look real carefully at it.. I will later..
And I have a program, that does many thing over and over to try and slow itself down, which I will try later as well..

So, Thank You for reminding me..

I have mostly stripped the old Board, that I had used for Testing of the 11/40, But since I sold the 11/40, this Board can be used for other things..
I am going to try and use it to Test and possibly fix the SAP (M8107) Board.. Then it would be hopefully helpful in testing the other Board..

001.jpg

After finding some of the Pins on the connector, that in the previous situation, were wired to Ground, and were not wired to Ground on this SAP Board.. I got bit 0 to work correctly.. I am slowly going to work thru each of the Bits, and hopefully it will show OK.. Or if there is a problem I will know where to look..

THANK YOU Marty
 
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Hi All;

After finding some of the Pins on the connector, that in the previous situation, were wired to Ground, and were not wired to Ground on this SAP Board.. I got bit 0 to work correctly.. I am slowly going to work thru each of the Bits, and hopefully it will show OK.. Or if there is a problem I will know where to look..
I have the first four bits wired, it takes 6 wires for each bit..
Next is bits 5 and 6.. They are Both done and Work fine..
The rest of the bits are going to be harder to follow, as they work with and thru adder(s) and Ram Memory on the SAP Board itself..
I decided to try something and I was/am surprised that it worked..
I am going to try some programs to see if it truly is working..
What did I do, I plugged in the SAP Board into slot 14, and I am using it instead of the My Home-made/built SBJ Board in slot 14..
With NO SSR (M8108) Board is Plugged into slot 13..
I have tried and plugged in the SSR (M8108) board into slot 13..
At this point I have no idea if it is working or Not..

I have Plugged in one of the Serial Cards, at this point I don't know if it is a working one or not..
But, the PDP 11/45 hasn't Blown up or died at this point..
I have tried Both of the DL-11W's (M7856)..
No Luck so far, I have one M7800, that I can try..

Could/Would someone with PDP 11 programming experience write up a simple (for You) program to Output a character all of the time.. Like a '0' to 777566 then a Jump back to '000000 and keep on repeating this..

I may have wasted most of this afternoon, I was using a memory Board that appeared to be OK, but it wasn't OK..
I have my Mostek Memory Board, which is working much better..
So, I will be starting all over..

THANK YOU Marty
 
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Hi All;

We NOW have ECHO, I am using one of the M7800 Boards..

Now to Load some programs..

It is NOW running Don's ZZ Program, which tests Memory..
Thank You Don..

The Next big thing is to get Any Second Serial Card to Work..

THANK YOU Marty
 
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Hi All;

Thank You Jack with Your Encouraging note..

I have found that if I threaten a computer, that it suddenly will start to work again..

But, sometimes it takes more than a threat of putting it away and working on something else..

I have to actually have to put it away and go work on that something else..

And then when I bring it back, it will start working again..

I can't explain it, but it seems to work quite often for me.. Old Iron jealousy..

THANK YOU Marty
 
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