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So I got my first PDP-11

NeXT said:
That system is absolutely filthy. It certainly wasn't last used in a regular computer room.
Click to expand...

Well, I went to my local Canadian Tire (hardware store) and got replacements for the missing screws. 4 screws/washers/locks for the front panel, one for that fan, and one for the power supply. I also got some course steel wool and went to town with it. Most of the crud is gone, and I was able to removed a lot of the rust, however some areas still have a thin layer. Still looks a lot better though. I also cleaned out the fan, and removed all the particles stuck between various places. The only place I couldn't clean up well was inside the backplane slots. Any way to get the particles that are stuck in them? I also rebent the warped areas, so now the operators panel fits properly and can be attached.

Going to now disassemble the PSU and clean that out.
 
Assuming there are no vital electronics in the way, you might what to give Naval Jelly a try at those hard to get at places. You could apply it with a soft brush then come behind with a damp cloth and thoroughly clean/rinse the area after about 20 minutes or so.
 
Agent Orange said:
Assuming there are no vital electronics in the way, you might what to give Naval Jelly a try at those hard to get at places. You could apply it with a soft brush then come behind with a damp cloth and thoroughly clean/rinse the area after about 20 minutes or so.
Click to expand...

I just dabbed a vacuum and scrubbed off as much dirt as possible. The more core electronics I just cleaned whatever got sucked up. Didn't want to disconnect too many things. Anyway, FINALLY got it all back together and in the chassis. Next up is the operators panel and various boards.

What is a good way to clean the pcb boards?
 
Ioncannon said:
I just dabbed a vacuum and scrubbed off as much dirt as possible. The more core electronics I just cleaned whatever got sucked up. Didn't want to disconnect too many things. Anyway, FINALLY got it all back together and in the chassis. Next up is the operators panel and various boards.

What is a good way to clean the pcb boards?
Click to expand...

Well, I always favored 91-100% alcohol with cotton swabs or Q-Tips. I'm sure you're going to hear of just about every method imaginable here on the forum (which is a good thing).
 
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So I have taken inventory of what I currently have and will use.

Three of the cards are RAM cards, and I will use the M7891, the /04's original ram card.
The CPU will be the M7263

I also have two M7856 cards, one of which is going into the PDP-11.

Finally I have a M7228, but it doesn't seem to be needed, since the M7856 also has a RTC?

So the way I have it laid out is:

M7263 M7263 M7263 M7263 M7263 M7263
M7891 M7891 M7891 M7891 M7891 M7891
EMPTY EMPTY EMPTY GRANT EMPTY EMPTY
M7856 M7856 M7856 M7856 EMPTY EMPTY
EMPTY EMPTY EMPTY EMPTY EMPTY EMPTY
EMPTY EMPTY EMPTY EMPTY EMPTY EMPTY
EMPTY EMPTY EMPTY EMPTY EMPTY EMPTY
EMPTY EMPTY EMPTY EMPTY EMPTY EMPTY
EMPTY EMPTY EMPTY EMPTY EMPTY EMPTY

First, are the cards setup correctly? Still reading about the PDP-11, so I may have incorrectly set it up.

Sadly the computer didn't come with a terminator card (more specifically, a M9312) so it isn't going to work right? Any other cards I will need to get the base system running? Also, I am not sure which way the grant card goes in. It doesn't have the tabs like other cards. Something like this: http://archive.computerhistory.org/...al_equipment_corporation_dec/102654905.lg.jpg .

Also, is there any way to know what rom chip is in the M9312 (like a part number)? Have a seller but don't want to get it if the chip isn't the /04 or /34 monitor.
 
Be sure to download a copy of the M9312 manual. You will see it has space for five roms on it. One contains the console emulator (I originally wrote ODT here, but that was sloppy), and the other four are bootstraps for individual devices. The manual tells you the rom numbers and the devices they go with.

Otherwise what you have there should work. You may also need to look under the backplane to look for places that the NPG grant chain was cut. It should only be cut for devices that do DMA, otherwise it should be present OR you can insert a "double grant" card (dual height) in an empty slot with a broken chain. Also be sure to stuff the rest of the unused slots D locations with grant cards (you did not indicate that in your diagram.)

As for your single grant cards, mind the shoulders machined in at the edges. If inserted correctly, the shoulders will land on the raised edges of the slot evenly (if backwards, the card will end up slanted. Alternately, look in the 11/34 manual (it is quite good) for a discussion of the signals on the SPC slots. It will tell show you the bus grant lines, and you can match them up with the fingers and traces on the grant card.

Lou
 
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You can find lots of M9312 BOOT ROM info at: http://www.ak6dn.dyndns.org/PDP-11/M9312/ There are only two versions of the CPU BOOT PROM, basically GENERIC (11/04-34,etc) and the 11/60-70 version. 99% of the M9312s come with the generic CPU BOOT PROM. The 11/60-70 version is not very common.

Also available are the source code and PROM images for virtually all the existing M9212 supported devices (as well as a custom diagnostic test PROM image ZZ).

You might also want to consider installing the 2nd DL11-W serial port and configuring it as a 9600baud TU-58 interface. Then attach it to a PC (or Linux even) serial port, and use it as a TU-58 emulator to load diagnostic images. See: http://www.ak6dn.dyndns.org/PDP-11/TU58/ for s/w and images.

I use this TU-58 emulator and diagnostics to check/verify my 11/34 and 11/44 systems all the time.

Don
AK6DN
 
Lou - N2MIY said:
Be sure to download a copy of the M9312 manual. You will see it has space for five roms on it. One contains the console emulator (I originally wrote ODT here, but that was sloppy), and the other four are bootstraps for individual devices. The manual tells you the rom numbers and the devices they go with.

Otherwise what you have there should work. You may also need to look under the backplane to look for places that the NPG grant chain was cut. It should only be cut for devices that do DMA, otherwise it should be present OR you can insert a "double grant" card (dual height) in an empty slot with a broken chain. Also be sure to stuff the rest of the unused slots D locations with grant cards (you did not indicate that in your diagram.)

As for your single grant cards, mind the shoulders machined in at the edges. If inserted correctly, the shoulders will land on the raised edges of the slot evenly (if backwards, the card will end up slanted. Alternately, look in the 11/34 manual (it is quite good) for a discussion of the signals on the SPC slots. It will tell show you the bus grant lines, and you can match them up with the fingers and traces on the grant card.

Lou
Click to expand...

I assumed that the slots could be empty after the terminator card. Seems I am going to have to get more grant cards, since the system only came with two :(.

AK6DN said:
You can find lots of M9312 BOOT ROM info at: http://www.ak6dn.dyndns.org/PDP-11/M9312/ There are only two versions of the CPU BOOT PROM, basically GENERIC (11/04-34,etc) and the 11/60-70 version. 99% of the M9312s come with the generic CPU BOOT PROM. The 11/60-70 version is not very common.

Also available are the source code and PROM images for virtually all the existing M9212 supported devices (as well as a custom diagnostic test PROM image ZZ).

You might also want to consider installing the 2nd DL11-W serial port and configuring it as a 9600baud TU-58 interface. Then attach it to a PC (or Linux even) serial port, and use it as a TU-58 emulator to load diagnostic images. See: http://www.ak6dn.dyndns.org/PDP-11/TU58/ for s/w and images.

I use this TU-58 emulator and diagnostics to check/verify my 11/34 and 11/44 systems all the time.

Don
AK6DN
Click to expand...

Thats great to hear, hopefully the one that arrives is correct. I knew of that website, but I don't have a burner that could write such old chips, so it would be useless to me.

I may actually implement that idea with the second serial port.
 
Ioncannon said:
I assumed that the slots could be empty after the terminator card. Seems I am going to have to get more grant cards, since the system only came with two :(.



Thats great to hear, hopefully the one that arrives is correct. I knew of that website, but I don't have a burner that could write such old chips, so it would be useless to me.

I may actually implement that idea with the second serial port.
Click to expand...

So the M9312 has arrived..... and just my luck it has the 233F1 rom in it =\. Did a double check and yea, it's the 11/60 rom. Seems the card came from an 11/70 since jumpers W9 and W10 are in. I am assuming the console will not work with a 11/04?

From reading the M9312 tech reference, W1-W5 have to be out, W6 out, W7 in, W9/W10 in while W11/W12 out, and currently W8 is out. Seems correct for a 11/04?
 
Well, at least you can terminate the bus properly. The 11/04,34 do use a different console emulator rom.

What other roms were on your M9312?

Lou

Ioncannon said:
So the M9312 has arrived..... and just my luck it has the 233F1 rom in it =\. Did a double check and yea, it's the 11/60 rom. Seems the card came from an 11/70 since jumpers W9 and W10 are in. I am assuming the console will not work with a 11/04?

From reading the M9312 tech reference, W1-W5 have to be out, W6 out, W7 in, W9/W10 in while W11/W12 out, and currently W8 is out. Seems correct for a 11/04?
Click to expand...
 
So the grant cards have arrived! Does this look correctly setup? I was reading the M7891 manual and noticed the DL11-PK bus doesn't have a MUD slot in slot 2, and according to the manual the ram won't work. So this is how I have it setup now:

M7263 M7263 M7263 M7263 M7263 M7263
EMPTY EMPTY EMPTY GRANT EMPTY EMPTY
M7891 M7891 M7891 M7891 M7891 M7891
EMPTY EMPTY EMPTY GRANT EMPTY EMPTY
EMPTY EMPTY M7856 M7856 M7856 M7856
EMPTY EMPTY M7856 M7856 M7856 M7856
EMPTY EMPTY EMPTY GRANT EMPTY EMPTY
EMPTY EMPTY EMPTY GRANT EMPTY EMPTY
M9312 EMPTY EMPTY GRANT EMPTY EMPTY

I learned how the UNIBUS sockets are laid out (so it isn't random!) and noticed I had the whole thing setup wrong. I also setup the two serial cards, one for the console and the other for TU56 emulation like AK6DN suggested. Also check the back, and the NPR jumpers are all there. I put the M9312 in the bottom left slot to terminate the bus. Does everything look correct?

Also noticed that there is a green and red LED on the M7891. The red one is for parity error, and the green one seems to be if there is 5v power, however I am not sure if it's battery only. Neither are on when powered on. Figured out from the schematic. There is a jumper that sets if power is from battery or 5v (mine is set to battery). D2 will only come on if battery power is applied. Anyone know what the J1 connector is for though?

Sadly the RUN light is still on when I flip the switch to HALT.
 
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11/04

11/04

For an 11/04 in a DD11-PK 9 slot CPU backplane, standard configuration is:

Slot 1 ... A-F: CPU module
Slot 2 ... A-F: MEMORY module
Slot 3 ... A-B: M9312 ... C-F: SPC or GRANT in D
Slot 4 ... A-B: MUD ..... C-F: SPC or GRANT in D
...
Slot 8 ... A-B: MUD ..... C-F: SPC or GRANT in D
Slot 9 ... A-B: M9302 ... C-F: SPC or GRANT in D


So you need to move your memory to 2/ABCDEF, the M9312 to 3/AB, and put an M9302 terminator at the end of the bus in 9/AB.
And of course have grant continuity cards in all unused SPC slots.
 
Ioncannon said:
So the way I have it laid out is:

M7263 M7263 M7263 M7263 M7263 M7263
M7891 M7891 M7891 M7891 M7891 M7891
EMPTY EMPTY EMPTY GRANT EMPTY EMPTY
M7856 M7856 M7856 M7856 EMPTY EMPTY
EMPTY EMPTY EMPTY EMPTY EMPTY EMPTY
EMPTY EMPTY EMPTY EMPTY EMPTY EMPTY
EMPTY EMPTY EMPTY EMPTY EMPTY EMPTY
EMPTY EMPTY EMPTY EMPTY EMPTY EMPTY
EMPTY EMPTY EMPTY EMPTY EMPTY EMPTY

First, are the cards setup correctly? Still reading about the PDP-11, so I may have incorrectly set it up.
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I hope you did NOT power on the system with the DL11-W installed in this location ... if you did, you may have toasted the interface on the card. All DEC UNIBUS backplanes have rows C-F as the SPC 'small peripheral controller' position. Rows A-B are either MUD 'modified unibus' (internal slots) or 'standard unibus' (first/last slot) in rows A-B.

Don
 
AK6DN said:
I hope you did NOT power on the system with the DL11-W installed in this location ... if you did, you may have toasted the interface on the card. All DEC UNIBUS backplanes have rows C-F as the SPC 'small peripheral controller' position. Rows A-B are either MUD 'modified unibus' (internal slots) or 'standard unibus' (first/last slot) in rows A-B.

Don
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Uh oh, may have done that =\. So the card is a write off? Can it still be used to complete the grant chain (out of grant cards) or will it cause a bus error? I swear I saw some configurations setup like that, oh well.

Update: So I moved the jumper on the M7891 to take power from 5v instead of battery and got the green LED to turn on (seems dim though). I also got some kind of response from the system! When the system is powered on the red parity error light comes on. When I flick the INIT switch and release, it goes off. Does this sound like the correct operation? Ordered a M9301 for termination and I am going to move the M9312 to slot 3 AB.
 
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Even if you broke this card, it's not a writeoff. I have done component level repairs on two DL11-Ws. They are pretty easy to work on.

With your M9302, I think you'll now have the right configuration. Did you check the underside of the backplane and verify the NPR grant chain is unbroken? You are using single grant cards (in slot D, which is correct) which will not bus CA1 to CB1 (but double-grant cards do this.) So at each SPC slot (3 through 9) verify that CA1 is wire wrapped to CB1. Later you will undo this jumper wherever a DMA option is installed.

Lou
 
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Actually you want an *M9302* for the end of the bus termination (terminator logic only) and NOT an *M9301* (which is an earlier less capable version of the M9312).

As to the status of your DL11-W that was mistakenly put in slots ABCD instead of CDEF, you'll have to test it and see. Assuming you don't have +20V/-5V core supplies (not common) and no battery backup +15/-15/-5V supplies (not common either) then you should be OK. DEC was ~reasonably~ consistent about using the same relative pins in each section for the same power/ground, but not in all cases (boxes supporting core memory especially).
 
AK6DN said:
Actually you want an *M9302* for the end of the bus termination (terminator logic only) and NOT an *M9301* (which is an earlier less capable version of the M9312).

As to the status of your DL11-W that was mistakenly put in slots ABCD instead of CDEF, you'll have to test it and see. Assuming you don't have +20V/-5V core supplies (not common) and no battery backup +15/-15/-5V supplies (not common either) then you should be OK. DEC was ~reasonably~ consistent about using the same relative pins in each section for the same power/ground, but not in all cases (boxes supporting core memory especially).
Click to expand...

Typo, it was a M9302 not M9301.

Lou - N2MIY said:
Even if you broke this card, it's not a writeoff. I have done component level repairs on two DL11-Ws. They are pretty easy to work on.

With your M9302, I think you'll now have the right configuration. Did you check the underside of the backplane and verify the NPR grant chain is unbroken? You are using single grant cards (in slot D, which is correct) which will not bus CA1 to CB1 (but double-grant cards do this.) So at each SPC slot (3 through 9) verify that CA1 is wire wrapped to CB1. Later you will undo this jumper wherever a DMA option is installed.

Lou
Click to expand...

Yes, I checked the NPR chain and all wires are still there.
 
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Ioncannon said:
Typo, it was a M9302 not M9301.



Yes, I checked the NPR chain and all wires are still there.
Click to expand...

Put the terminator card into slot 9 at A/B. Parity error light no longer lights up (might be coincidence) but RUN light is still stuck on.
 
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