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PDP 11/73 in BA213 Cabinet Error

Sorry Steve, you are still not photographing the correct part of the front panel. It is the top (narrow width) of the panel, not the long side.

Yes. If the rotary switch is used, the links should be removed. Likewise, if the links are used, the rotary switch (if it exists) should be set to a specific setting. If we have the links installed and the rotary switch set to a valid setting - they will result in the CPU setting the baudrate to the wire-OR of the links and the switch setting. Not the desired outcome...

I’ll have a look for the manual I found with a poor-quality photograph.

Dave
 
daver2 said:
Yes. If the rotary switch is used, the links should be removed. Likewise, if the links are used, the rotary switch (if it exists) should be set to a specific setting. If we have the links installed and the rotary switch set to a valid setting - they will result in the CPU setting the baudrate to the wire-OR of the links and the switch setting. Not the desired outcome...
Click to expand...

On the M7554 KDJ11-D board the 34-pin connector has 3 pins for the DLART0 baud rate, 3 pins for the DLART1 baud rate, and 4 pins for the boot select.

If you have the non S-handle version of the M7554 KDJ11-D board and the bulkhead panel for that version of the board which attaches to the 34-pin connector, it has two rotary switches for the baud rates, and a third rotary switch for the boot select.

On the S-handle version of the M7554 KDJ11-D board there is a single rotary switch. I am almost 100% certain that switch is only for the boot select, and the baud rates must be selected using the jumpers on the M7554 KDJ11-D board.

Go back to the first post on this thread and click on the attached photo to zoom in on it. The yellow rotary switch under the hex LED display has 16 switch positions 0 through F.

(My guess is that the red MMJ plug might be a loopback test connector).
 
daver2 said:
Sorry Steve, you are still not photographing the correct part of the front panel. It is the top (narrow width) of the panel, not the long side.

Yes. If the rotary switch is used, the links should be removed. Likewise, if the links are used, the rotary switch (if it exists) should be set to a specific setting. If we have the links installed and the rotary switch set to a valid setting - they will result in the CPU setting the baudrate to the wire-OR of the links and the switch setting. Not the desired outcome...

I’ll have a look for the manual I found with a poor-quality photograph.

Dave
Click to expand...
Sorry Dave look here:-
 
daver2 said:
Sorry Steve, you are still not photographing the correct part of the front panel. It is the top (narrow width) of the panel, not the long side.

Yes. If the rotary switch is used, the links should be removed. Likewise, if the links are used, the rotary switch (if it exists) should be set to a specific setting. If we have the links installed and the rotary switch set to a valid setting - they will result in the CPU setting the baudrate to the wire-OR of the links and the switch setting. Not the desired outcome...

I’ll have a look for the manual I found with a poor-quality photograph.

Dave
Click to expand...
Sorry Dave

i have removed the strip to make sure:-
 

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Just to be clear here are the jumper settings I have:-
W13 OFF
W9 ON
W6 OFF
W4 ON
W12 ON
W7 OFF
W10 ON
W11 OFF
W1 OFF
W22 ON
W2 ON
W3 OFF
W5 OFF
W8 OFF
W24 ON
W25 OFF

JUMPERS W2, W21 AND W23 are not available.
 
Thanks for the photograph Steve. There are so many different parts available that I just wanted to make sure...

OK, I have reviewed your links against the documentation (using Figure 2-1 of http://www.bitsavers.org/pdf/dec/pdp11/1173/EK-KDJ1D-UG_KDJ11-D_May87.pdf as a reference - manual page 2-2 PDF page 64) as this matches the photograph of the card you have posted; with the following observations:

I am not sure why W2 is installed. It should not be. W2, W3, W5, W8 and W22 are related to the boot options. You clearly want boot option 0 at the moment (test, enter console and in English). This requires that the front panel switch be set to 0 (with W2, W3, W5 and W8 OUT and W22 IN). See note 2 on manual page 2-8. However, this is unlikely to be your problem because having W2 installed rather than removed will only make the bit a 0 - as will having the switch at position 0.

W20, W21 and W23 are actually present. They are not, however, user-configurable links but wire links installed at the factory. We can, therefore, discount these.

I can't quite make out the part number on the DRAM chips - but I am guessing this board is 1.5 MB - so W25 OUT would be correct.

My confusion is related to the BOOT EPROMS fitted and the state of R14 and W13. If you are stating that W13 is OUT/OFF then R14 (probably a wire link) must be IN and the BOOT EPROMS should be 16K. This would be correct if DEC are referring to the size of one of the EPROM devices (a 27128 is 16KB on its own). If DEC are referring to the combined size of the two EPROMS, this configuration is incorrect and it should be R14 OUT and W13 IN.

Perhaps someone else could comment on this before you make any changes?

W24 being IN also refers to something DEC identify as "Special Application". The manual (note 5 on page 2-4) states that W24 (and W25) are factory installed. However, that doesn't mean that no one has 'fiddled' in the meantime of course...

The serial baudrates for both DLARTs appear to be configured for 9600.

Just my observations.

Dave
 
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Removed jumper W2 and the behaviour is the same.
The next idea is to try the CPU in different BA213 slots.
Also is it worth the risk of moving another working MicroVAX CPU into the BA213 cabinet to see what happens.
There are two blue capacitors on this cpu board.
Do you think it’s worth testing them with an ESR meter?
 
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>>> Removed jumper W2 and the behaviour is the same.

That's what I thought.

>>> The next idea is to try the CPU in different BA213 slots.

Clutching at straws IMHO.

>>> Also is it worth the risk of moving another working MicroVAX CPU into the BA213 cabinet to see what happens.

Unlikely have any effect. If you have the DC OK lamp on, and the power supplies are running, you should be good to go with a single board.

>>> There are two blue capacitors on this cpu board. Do you think it’s worth testing them with an ESR meter?

Nah!

How are you operating your HALT button out of interest? Is it accidentally pushed in?!

Dave
 
Hunta said:
Dump of content 261E5 and 262E5 - these are two files of 16384 bytes each, that is, 16 kb.
This is also indicated by the E5 suffix - 16384 bytes
Click to expand...

So we are saying that W13 out (and, presumably, R14 IN) is correct for these specific EPROMS and DEC are referring to the size of each EPROM as opposed to the combined size of both EPROMS?

Steve, I have just noticed an interesting thing. I am on my laptop this morning and I can see the edges of the front panel in your photographs. On the iPad last night I couldn't. And, yes, I did try scrolling/panning... That accounts for my inability to see the rotary switches - the iPad was not showing me the specific area of your photographs I wanted to see! I wonder if that is a 'nit' that I should be reporting? Anyhow, I now see unequivocally, that the rotary switch for the BAUDRATE setting is not present on the front panel!

The next thing Steve is your HALT switch. Is it permanently ON?

Dave
 
daver2 said:
So we are saying that W13 out (and, presumably, R14 IN) is correct for these specific EPROMS and DEC are referring to the size of each EPROM as opposed to the combined size of both EPROMS?
Click to expand...
Yes.
I have an M7554-PB board (from a DECServer), the contents of the ROM are specific, so I replaced the ROM chip with 27C512, and duplicated the contents four times - the board works.
 
daver2 said:
So we are saying that W13 out (and, presumably, R14 IN) is correct for these specific EPROMS and DEC are referring to the size of each EPROM as opposed to the combined size of both EPROMS?

Steve, I have just noticed an interesting thing. I am on my laptop this morning and I can see the edges of the front panel in your photographs. On the iPad last night I couldn't. And, yes, I did try scrolling/panning... That accounts for my inability to see the rotary switches - the iPad was not showing me the specific area of your photographs I wanted to see! I wonder if that is a 'nit' that I should be reporting? Anyhow, I now see unequivocally, that the rotary switch for the BAUDRATE setting is not present on the front panel!

The next thing Steve is your HALT switch. Is it permanently ON?

Dave
Click to expand...
Hello Dave,

Where is my HALT switch? I can’t see one.
 
I don’t have anything like that :)

I just have a bare chassis which I understand was used as a Q-bus test bed for VAX‘s and PDP 11’s.

Are you saying a halt signal is passed to the CPU via the backplane?

This control unit is not connected to anything at the moment. I guess a HALT signal could be passed into this unit via a ribbon cable and then into the CPU via the backplane.
 

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That panel also contains the "DC OK" LED that I suggested you check for (just to the right of the HALT switch in post #35). The "DC OK" signal is another one that goes to the backplane. Without it you are not going to get anywhere either...

Dave
 
I think I have found the backplane ribbon (see photo).

Now I will try and find a DC OK pinout and a halt switch connector as I guess the chances of finding a suitable front panel are minimal.
 

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