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Need a bit of help resurrecting my PDP-11/73

No problem.

My 10 cents (for what it's worth) is:

If you are going to use the DEC case, power supply and QBUS backplane - I would stick with the 11/73 CPU and QBUS memory (to keep it hardware authentic).

It now depends what you are going to do with the system after that...

I would migrate to a DLV11-J serial card and the TU58 emulator next - as it involves the minimum of hardware within the QBUS box. As I said, happy to put you one in the post 'free gratis' - but it won't get to you now to open it on Christmas morning :-(!

This would get you the XXDP diagnostics and RT-11 (and be as close to DEC equipment as possible - but without the physical 'disk/tape' media).

You can obtain modified DD drivers for RT-11 (and I would guess RSX-11) to be able to drive the TU58 emulator as a large disk drive (much larger than than the tapes). With a fast serial line interface you will probably achieve similar speeds to a real (slow) disk drive?

You can then identify whether you want to move on to the RQDX3 and try to get that working with either a real DEC RDxx disk - or one of the RDxx disk emulators). The alternative would be to find a QBUS SCSI card and one of the SCSI2SD or SCSI2CF interfaces. These work brilliantly. XXDP would be paramount to testing out your RQDX3 and RDxx chain.

You could also consider QBONE to emulate the disk devices...

Dave
 
GreyHairedDECfan said:
Ok. I found where to do the device translations so I can set a TT: port to tie to the DD0: drive. I have to do some research to determine the correct CSR and Vector to use.
Click to expand...

The TU58 drivers on the PDP-11 side are all written for a simple DL11 style serial port with just four CSRs (RX/TX status, RX/TX data) at address 776500 vector 300.
DZ11 or DH11 or more complex multiport serial cards are not supported.

Don

TU58EM author, site: https://www.ak6dn.com/PDP-11/TU58/ and https://www.ak6dn.com/PDP-11/TU58/tu58em/index.html
 
daver2 said:
No problem.

My 10 cents (for what it's worth) is:

If you are going to use the DEC case, power supply and QBUS backplane - I would stick with the 11/73 CPU and QBUS memory (to keep it hardware authentic).

It now depends what you are going to do with the system after that...

I would migrate to a DLV11-J serial card and the TU58 emulator next - as it involves the minimum of hardware within the QBUS box. As I said, happy to put you one in the post 'free gratis' - but it won't get to you now to open it on Christmas morning :-(!

This would get you the XXDP diagnostics and RT-11 (and be as close to DEC equipment as possible - but without the physical 'disk/tape' media).

You can obtain modified DD drivers for RT-11 (and I would guess RSX-11) to be able to drive the TU58 emulator as a large disk drive (much larger than than the tapes). With a fast serial line interface you will probably achieve similar speeds to a real (slow) disk drive?

You can then identify whether you want to move on to the RQDX3 and try to get that working with either a real DEC RDxx disk - or one of the RDxx disk emulators). The alternative would be to find a QBUS SCSI card and one of the SCSI2SD or SCSI2CF interfaces. These work brilliantly. XXDP would be paramount to testing out your RQDX3 and RDxx chain.

You could also consider QBONE to emulate the disk devices...

Dave
Click to expand...

Sent you a PM.
 
DLV11J configured and ready to install, also I removed one of the 1"x4" blank plates on the back panel and built a replacement designed to hold the DB25 end of the cable I have on order. So I'll have a clean cable connection rather than just running the wire through the hole. Last, I tested tu58fs and it's ready to go with the 7 xxdp diagnostics.

When I install the DLV11J, I plan to add it in last, behind the RQDX3 and TK50 controllers. I believe that should be ok from a grant perspective (no gaps), but wanted to check with the guru's.
 
So despite of the extraordinary efforts of someone very knowledgeable about these drives, we were unable to get data off of my hard disk, though we did get it to start spinning again. But reinstalled in my '73, it won't unlock or spin at all. So I'm guessing there is a power supply issue, or a bad RQDX3 controller, compounding the issue.

I hooked up tu58fs to load RT-11 next. It tried booting from the (simulated) tape drive, but failed with error 15 (drive not ready). I'm pretty sure I configured the DLV11J correctly, and I'm using a prebuilt DB25 cable for it but will have to recheck. I can set up another DLV card and try that as well.
 
Perform a system MAP and see if the DLV11-J appears at the correct locations within the MAP that you configured (176500 upwards - well, the 22 bit equivalent).

Have you got a second terminal (or terminal emulator) you can connect up to the serial port on the DLV11-J?

You can write characters to the transmit buffer using ODT (and you should see them appear on the terminal) and you should be able to type a character on the terminal and see the correct character code appearing in the receive buffer.

Failing that, loopback the DLV11-J serial port and test it out. The only thing this won't detect is incorrectly configured serial parameters (baudrate, data bits, parity and number of stop bits). The transmitter and receiver will be set-up the same way - so two wrongs make a right!

Dave
 
Haven't checked in on this thread in a long while, but if you're still having problems and in Northern MD you should bring some of this stuff to my house and we can take a look at it together.

PM me if interested.
 
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