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Building a PDP11/83

B

bobaboba

Experienced Member
Joined
Sep 7, 2013
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400
Location
Scotland
I've been looking for a small pdp11 for a while with no luck - what's been available either looked in too poor condition for a pdp11 novice or was inconveniently far away to collect. So I've been collecting together some bits to DIY.

Anyway, I've at last got hold of a cabinet so I've now got the following bits and I want to make a start:
- BA123 cabinet with power supply and load board (I was told that it came from a microvax which died and got stripped).
- M8190-AE (KDJ11-BF?) which I think is a PDP 11/83 board
- M8637-E (MSV11-JE) 2M PMI memory
- M7555 (RQDX3) disk controller
- M3119 (CXY08 ) serial board
- M3104 (DHV11) serial board
- RD54 disk (not guaranteed working though - sold as seen)

I'm really a pdp8 man and this is my first dabble with a pdp11 so I could use some pointers to how to get started, what else I'll need, useful things to read and how to check things out. Also I've no idea how to eventually build an OS and what other bits I'll need to transfer stuff from (I suppose) a PC onto the RD54. I've not found a manual for the cpu board, is there one on-line?

Any/all input welcome ;)
 
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Of course there are manuals for all of that stuff online.

The M8637 MSV11-J PMI memory board should go in slot 1 to operate in PMI mode.
The M8190 KDJ11-B CPU board should go in slot 2 to operate in PMI mode with the M8637 MSV11-J.

Does the M8190 KDJ11-B CPU board have a 15MHz or 18MHz oscillator? Does it have the optional FPJ11 Floating-Point Accelerator (FPA) chip installed?

Do you have the console bulkhead panel for the M8190 KDJ11-B CPU board? Makes things easier if you do.

EK-KDJ1B-UG-001 KDJ11-B CPU Module User's Guide
www.bitsavers.org/pdf/dec/pdp11/1173/EK-KDJ1B-UG_KDJ11-B_Nov86.pdf

AZ-GLBAA-MN MicroVAX II 630QB Technical Manual
www.bitsavers.org/pdf/dec/vax/630/AX-GLBAA-MN_MicroVAX_II_630QB_Technical_Manual_Nov85.pdf
Page 22 of the PDF, Page 1-11, Figure 1-9 Backplane Grant Continuity. Make sure you understand how the BA123 backplane works. Slots 1-4 are Q22/CD, the rest are Q22/Q22.
 
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Thanks Gslick & Peter

gslick said:
Of course there are manuals for all of that stuff online.
Click to expand...

Yes, I guess, but not always called what you'd expect or in the folder you'd look in ;)

gslick said:
Does the M8190 KDJ11-B CPU board have a 15MHz or 18MHz oscillator? Does it have the optional FPJ11 Floating-Point Accelerator (FPA) chip installed?
Click to expand...

18MHz and yes it has the FPA chip.

gslick said:
Do you have the console bulkhead panel for the M8190 KDJ11-B CPU board? Makes things easier if you do.
Click to expand...

No don't think so. Actually I don't really know what it is yet ;). There are some bits and cables in the case but left over from the microvax.

gslick said:
Page 22 of the PDF, Page 1-11, Figure 1-9 Backplane Grant Continuity. Make sure you understand how the BA123 backplane works. Slots 1-4 are Q22/CD, the rest are Q22/Q22.
Click to expand...

OK, I've read that. I don't think I have any 'grant continuity cards'. Maybe I need to visit Ebay?
 
bobaboba said:
No don't think so. Actually I don't really know what it is yet ;). There are some bits and cables in the case but left over from the microvax.
Click to expand...

I've got John Wilson's pigtails made up if you wind up needing some. Of course you can run the boards yourself, the design is freely available.

bobaboba said:
OK, I've read that. I don't think I have any 'grant continuity cards'. Maybe I need to visit Ebay?
Click to expand...

Depending on how you lay out your cards, you probably won't need any. Just make sure there are no "holes" in the grant chain.
 
EK-CXY08-IN-001, CXY08-AF 8-Line Asynchronous Multiplexer Option Installation Guide:
vaxhaven.com/images/f/fe/EK-CXY08-IN-001.pdf

I have an original hardcopy of EK-CXY08-TM, CXY08 Technical Manual. Don't know if anyone has bothered to scan that manual yet.

Aren't all CXY08 boards S-handle boards? You wouldn't be able to use one of those in a BA123.

I think the CXY08 is functional equivalent to the dual wide M3107 DHQ11, which has a superset of the functionality of the quad wide M3104 DHV11.
 
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Some reading to do before I try to fire up any cards I guess.
At least the power supply seems to supply power.
glitch said:
I've got John Wilson's pigtails made up if you wind up needing some. Of course you can run the boards yourself, the design is freely available.
Click to expand...

Do you have a link for that please to see what's involved?
 
bobaboba said:
There are some bits and cables in the case but left over from the microvax.
Click to expand...

Did you get an M9058 RQDX signal distribution board? You need one of those and some cables to connect the M7555 RQDX3 to the RD54.

M9058.jpg

Are there any four port DB25 H3173-A distribution panels? There should be two of those for the M3014 DHV11. No need worrying about getting the DVH11 going until after you get an OS up and running on the system. Might be interesting to hang a few terminals off of the system if you managed to get 2.11BSD installed and running.
EK-DHV11-TM-002 DHV11 Technical Manual
www.bitsavers.org/pdf/dec/qbus/EK-DHV11-TM-002.pdf
 
gslick said:
http://www.dbit.com/wilson/dlvdb25/
Click to expand...

Thanks - that looks like something that even I could manage!

gslick said:
Did you get an M9058 RQDX signal distribution board? You need one of those and some cables to connect the M7555 RQDX3 to the RD54.
Click to expand...

Alas no, but I had reaslised that something was required and I've been looking at copying this page http://avitech.com.au/?page_id=645 (or parts of it anyway).

gslick said:
Are there any four port DB25 H3173-A distribution panels?
Click to expand...

Again no - just bare board, but I'm hoping that cables won't be too difficult to sort out (connectors might of course).

PDP11 bits aren't too common this side of the great waters so just a case of making do.
 
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So things have progressed in the last couple of weeks. I found that I did after all have a distribution board for the RQDX3/RD50, I just didn't know what I was looking at. A minor amount of metalwork and wiring was needed to hook up the processor board. Most things at least seem to work (except I don't know about the RD50 yet). I can run through the routines on the processor from the manual, it seems to recognise the right amount of memory and the disk controller, and I can try to boot from the disk though nothing much happens (but I think the disk clicks a bit). No reason there would be an OS on the disk of course!

So the next thing I need to do is try to get an operating system onto the disk. I've done a bit of reading about a TU58 emulator so is this a route to test and/or copy things to the RD50? Could I for instance boot from a simulated TU58 and copy an OS from Simh to the RD50?

I've had a brief look at a SCSI2SD route but that looks as though it would cost a lot more than the parts I've got so far!

Any pointers welcome.
 
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Previously you said you had an RD54 (Maxtor XT2190), not RD50. Which you do have?

The TU58 emulation might need a second serial port in addition to the console port. Someone else here could verify that. The M3104 DHV11 can't be used for that. You would need something like an M8028 DLV11-F or an M8043 DLV11-J.

If you do get TU58 emulation going the first thing you should do is run XXDP diagnostics and verify that the M8190 KDJ11-B CPU, M8637 MSV11-J memory, M7555 RQDX3 controller, and RD disk are working. You can use the XXDP diagnostics to low level format the RD disk if necessary.

If everything passes XXDP diagnostics, you could use either TU58 emulation or VTserver to copy files or a disk image to the RD disk.

Another option would be try hooking up a 5.25-inch floppy to the M7555 RQDX3 controller as an RX33. The somewhat common Teac FD55-GFR should work as an RX33. If you have a PC with a 5.25-inch floppy you should be able to write RX33 images to floppies. Then you could boot XXDP diagnostics or RT-11 from floppies.
 
Ah yes, it's a RD54, not a RD50. Had to dismantle things again to verify what I'd actually got!

Sounds as though my collection of boards isn't up to the job yet. Shortage of funds means that I've collected things I could get from eBay for a very low bid if they looked as though they might be useful. Ah well - anyone in the UK with a spare DLV11? I can offer a CXY08 to swap?

I noticed this post on the forum http://www.vcfed.org/forum/showthread.php?25888-TU58-emulator-and-M3104-DHV11-A . Anyone tried using the console port?

I believe I could sort out a floppy connection, I've several candidates, but it's not a great route to installing RSX later (intended goal).
 
I wouldn't give up on the RD54 not having an O/S installed at this point. I would check all cables are correctly seated etc. RQDX3 is configured correctly, last device on bus with no gaps. And see if you can boot this.
 
I'm also working on getting a PDP-11/83 pieced together in a BA23 enclosure. For anyone else doing this, I found http://pdp-11.org.ru/~form/pdp11-83/ to have some helpful tips. Unless you read Russian you'll have to translate it with something like google translate. That page tells how to DIY a lot of cables in case you can't find originals, as well as using a PC power supply and a naked Q-Bus backplane instead of one pre-mounted in a BAxxx enclosure.
 
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