Rehabilitating a little PDP-11/73: what do I need?

[atomicthumbs]

I have this PDP-11/73. I work at an electronics recycler, and someone recycled a Kevex Delta/8000/9000 (depending on which of the PCB markings and data plates you read) scanning electron microscope controller. I was dismantling it in an attempt to part it out, and I noticed that one of the pieces was its own little sub-chassis. I didn't realize what it was until I pulled out the M8192 and saw "Digital" on the back.

The Q-bus cards I have:

• M8192 CPU card
• Camintonn 1.1 kword (I think) RAM card
• GTSC 304 4-port serial card (DLV11-J compatible)
• Data Translation EP050 data aqcuisition card
• Kevex electron microscope controller card
• GTSC 360/361 SCSI controller card

Unfortunately, the processor was the last card I removed, so I'm not sure I have the cards back in the correct order.

I have the cards, chassis, a pair of (enormous) Iomega Bernoulli SCSI drives, and a Quantum ProFile SCSI hard drive. I believe the ProFile was connected to the PDP, but I'm not sure, considering I can't find a SCSI cable of the right size to connect both to the hard drive and to the controller. The Bernoulli drives were definitely connected to it, though.

Aside from the power supply (judging by the way the backplane was wired up, it only needs +12v, +5v, and ground, IIRC), a terminal, and a boot disk (hopefully the hard drive since that'd make things easy), what else will I need to boot this thing? Will it automatically recognize the Q-bus cards? How do I make a cable to connect the DLV11-J's console port to a modern PC with a serial port as a terminal emulator?

And, finally, what operating systems can I run on this bad boy?

 

[TiggerLAS]

Assuming it is a "straight through" backplane, you'll want your CPU in the top slot,
followed immediately by the memory. After that, the 4-port serial card, and then
your SCSI card. The EP050 and microscope cards won't be immediately useful,
so for testing purposes, I'd leave them out.

DLV11 pinouts can be found here -- http://www.pinouts.org.uk/index.php?page=DLV11-J_Serial_Connector

What will be a bit time-consuming is getting an operating system on it,
once you have a SCSI disk attached to it. This is typically done via the
serial port, and a program called VTServer.

Since I don't know if your configuration has a line-time clock signal,
I'm not sure what that will translate to in the way of operating systems.
Some operating systems require this signal.

This is typically a signal provided by a DEC power supply;
not sure what you'd need for that.

Operating systems include:
RT-11
RSX11-M+
RSTS/E

. . .as well as some variations of Unix/BSD.

I'm sure more folks will chime in with details shortly.

 

[Marty]

Hi All;
AtomicThumbs , "" a pair of (enormous) Iomega Bernoulli SCSI drives, and a Quantum ProFile SCSI hard drive. "", "" And, finally, what operating systems can I run on this bad boy? "" If either of the drives, that you mentioned that You have came with the System, then it may/might have an Operating System already on it/them.. Otherwise, Yes You would need to put something on it Yourself..

THANK YOU Marty

 

[jackrubin]

Having a SCSI controller as part of the system should make system setup pretty easy. No need for VTServer if you can come up with a SCSI ZIP drive or a SCSI2SD controller - http://www.codesrc.com/mediawiki/index.php?title=SCSI2SD . Either will let you transfer a bootable disk image from SIMH or PUTR to media that can then be used by your qbus system.

RT11 is the smallest and easiest DEC OS to install.

Jack

 

[gslick]

The Q-bus cards I have:

• M8192 CPU card
• Camintonn 1.1 kword (I think) RAM card
• GTSC 304 4-port serial card (DLV11-J compatible)
• Data Translation EP050 data aqcuisition card
• Kevex electron microscope controller card
• GTSC 360/361 SCSI controller card

What type and how many DRAM chips are on the memory board? Some examples:
32x 64Kb chips = 256KB without parity
36x 64Kb chips = 256KB with parity
32x 256Kb chips = 1MB without parity
36x 256Kb chips = 1MB with parity

I have never heard of a GTSC 360/361 SCSI controller card. It would be interesting to see some high resolution photos of that card.

-Glen

 

[gslick]

Since I don't know if your configuration has a line-time clock signal,
I'm not sure what that will translate to in the way of operating systems.
Some operating systems require this signal.

This is typically a signal provided by a DEC power supply;
not sure what you'd need for that.

Oh yeah, I think you also need something to drive the Power OK and DC OK signals that normally would come from the power supply, in addition to the LTC / Bus Event signal.

 

[MattisLind]

Having a SCSI controller as part of the system should make system setup pretty easy. No need for VTServer if you can come up with a SCSI ZIP drive or a SCSI2SD controller - http://www.codesrc.com/mediawiki/index.php?title=SCSI2SD . Either will let you transfer a bootable disk image from SIMH or PUTR to media that can then be used by your qbus system.

RT11 is the smallest and easiest DEC OS to install.

Jack

If one like to run RSX11-M on the system I would recommend looking at this article by Jordi Guillaumes Pons. It covers how to install RSX11-M in a SIMH environment. I replaced all references to the DB disk driver with DU and had it create a bootable image that I simply did a linux dd to a SCSI disk. If I just had been clever enough to switch on the LTC switch it would have booted straight away...

 

[Marty]

Hi All;
"" Oh yeah, I think you also need something to drive the Power OK and DC OK signals that normally would come from the power supply, in addition to the LTC / Bus Event signal. ""
If You use the Basic Circuit from Reinhard, it will generate the correct signals.. I modified it some and used it on my PDP 11/45, And His was for a QBus machine in the first place.. I think there was a wiring circuit error, which is easily corrected, Don't put in the wire, I looked and What I had to do was use separate Switches for the two Circuits.. Where He used one switch and connected points 1 and 3 on the 7414 IC, I used two seperate switches in the same housing.. This is for the Power OK and DC OK signals only..
Here is a link to a picture of my Board, it is #59 at this link --
www.vintage-computer.com/vcforum/showthread.php?40889-Pdp-11-45/page6
And Here is the link to pdp11gy, which should get you to the correct page..
http://www.pdp11gy.com/indexE.html#file:///E:/homepage/indexE.html
There is a "Description" Link on this page, and this (I think) is the page with the Schematic..
"" in addition to the LTC / Bus Event signal. "" Reinhard, also has a Schematic for an LTC circuit as well.. So, with that You should be good to go..
I am having "Mouse" problems at the present, so checking out the links doesn't always work for me at the present..



THANK YOU Marty

 

[daver2]

Nice find!

1.1 K word memory is definitely not correct IMO.

Take a look at http://www.diane-neisius.de/pdp11/index_E.html for how Diane resurrected a little 11/03 system. This may give you some ideas about how to proceed.

I would start off small with the processor, memory, DLV11-J compatible (not the disk drives or controller) and try to get it working in ODT first. You can then add additional cards and sub-systems in order to make a larger system.

I am not sure if the dual height 11/73 CPU contained the DEC bootstrap or whether this was external (in the disk controller card).

You should be able to use a PC and a TU58 emulator to even boot up the minimum system and get some sign of life from it.

Incidentally, I am looking for a dual height 4 or 8 slot backplane myself to resurrect a small 11/02 I have the cards for. Unfortunately, I was let down by a supplier who said he had a few of them and then decided to take my money and not send the goods. Thanks to PayPAL I got my money back - but I am still minus my backplane - so if you come across any more sent for recycling I maybe in the market!

Good luck with your 73.

Dave

 

[cruff]

1.1 K word memory is definitely not correct IMO.

Yup, you won't run much of anything in 1.1 KW, certainly not any operating system.

I am not sure if the dual height 11/73 CPU contained the DEC bootstrap or whether this was external (in the disk controller card).

My M8192 certainly does not have a bootstrap on the card itself. I use the bootstrap on my CQD-220/MT SCSI controller, so perhaps the GTSC 360/361 SCSI controller has a bootstrap ROM on it. I also have a MXV11-BF with bootstrap ROMs on it, but since you can't use those ROMs without also having the MXV11's console port enabled, and the console port on that board has a failed -12V DC/DC converter, I can't use that one. :-( I haven't had the time to reverse engineer the -12V supply to see if I can repair it.

 

[tingo]

That is a neat little PDP-11.

 

[atomicthumbs]

Yup, you won't run much of anything in 1.1 KW, certainly not any operating system.



My M8192 certainly does not have a bootstrap on the card itself. I use the bootstrap on my CQD-220/MT SCSI controller, so perhaps the GTSC 360/361 SCSI controller has a bootstrap ROM on it. I also have a MXV11-BF with bootstrap ROMs on it, but since you can't use those ROMs without also having the MXV11's console port enabled, and the console port on that board has a failed -12V DC/DC converter, I can't use that one. :-( I haven't had the time to reverse engineer the -12V supply to see if I can repair it.

correction: it was 1.1 megawords, if not just 1024. can't take photos/go recount as I am sick and computer is elsewhere but IIRC it was 18x4 256 kbit chips.