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WHOOO HOOO! I'm getting a PDP-11/23!

Hello again, all,

After the collapse of my last purchase, where I didn't end up getting the DLV11-J card, I embarked on another quest to obtain another serial I/O port for my PDP-11/23.

I am now waiting on the arrival of another DLV-11 card, I believe it is a DLV11-F, AKA M8028. It seems to be another single serial I/O port, but that is all I need. Too bad that I will take up two slots with two cards, each having a single SIO port, but that's the way it is going right now.

My new question is where to plug this card in? I have a BA11-N chassis with H9273 4x9 Q18/CD backplane, and in the top four slots, on the left hand side of the card cage (as you look into it at the handles on the top edge of the cards) I have the following double size QBUS cards:

M8186 (CPU)
M8084 DB (32K memory)
M8084 DB (32K memory)
M7490 DLV11 (single SIO port)

Then, I have a quad size card:

M8012 (boot/terminator)

And then the four remaining slots under that are empty.

So, I am wondering, do I plug in the "new" M8028 card beside the M7940, on the right side, above the M8012, or do I move the M8012 card down one slot and plug the new M8028 card under the M7940 card on the left side?

Thanks very much, in advance, for your patience and attention.

smp
 
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You've got a straight-through backplane, so double-width cards go down the left side only. IIRC, it's possible to damage an AB dual-width card by plugging it into the CD sockets.
 
glitch said:
You've got a straight-through backplane, so double-width cards go down the left side only. IIRC, it's possible to damage an AB dual-width card by plugging it into the CD sockets.
Click to expand...

Super! Thanks a million. That was the conclusion that I had come to, but it is really great to hear this from someone else.

Thanks again.

smp
 
Here is another newbie question:

In searching out information about where to plug in the second SIO card, I saw some information about the M8012 Boot/Termination board that appears to be unclear, if not contradictory. In one place, I read that the M8012 board should be located in the last slot in the backplane directly after any other boards in the system, and in another place, I read that the M8012 board should be located in the last usable slot in the backplane.

As I stated in my previous message, the first four slots in my system are now occupied by the CPU, 2 memory boards and the SIO board. The M8012 board is in the fifth slot, leaving slots six through nine empty. Is this correct?

Another arrangement, one that puts the M8012 board in the last usable slot in the backplane, would put the M8012 board in slot nine. That would have the first four slots taken up by the CPU, 2 memory boards, and the SIO board, then slots five through eight would be empty, and then finally the M8012 board in slot nine. Would this arrangement be proper?

Which is correct? Should I have the M8012 Boot/Termination board immediately follow after the other boards in the system, or should I move the M8012 board to slot nine, the last useable slot in the backplane?

Thanks very much, once again, for your patience and attention!

smp
 
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M8012 needs to go in slot nine. It should always be the last slot in the backplane. It is perfectly OK to have empty slots between the last card and the M8012.

While on the topic of M8012, if you are ever feeling adventurous, the roms can be upgraded to the 11/23+ roms (the ones for M8189). I have done it twice and may have even written it up in a thread here somewhere. The reason for doing this is specifically to get the DU: bootstrap if you add an RQDXn or other MSCP disk controller someday.

Also, your M8028 should work fine. I had one in a system once in exactly the same service you are using yours.

Lou
 
Lou - N2MIY said:
M8012 needs to go in slot nine. It should always be the last slot in the backplane. It is perfectly OK to have empty slots between the last card and the M8012.
Click to expand...

Thanks very much, Lou. I greatly appreciate the assistance. There is so much information about DEC equipment, I get myself confused. Throw in a slightly different wording intended to mean the same thing, and someone like me can easily get all wrapped around the axle, so to speak. It's a blessing to be able to come here and ask a question and have the confusion cleared up - at least until the next time. 8-)

smp
 
No problem, glad to help. I learned this all the hard way myself, so it's good to put the knowledge to use. An 11/23 is the perfect starter dec machine.

For the record, the thread with my writeup on BDV11 rom upgrades is here: http://www.vintage-computer.com/vcforum/archive/index.php/t-24754.html?

That whole thread was on Qbus memories and was jam packed with good stuff from the folks here.

Lou
 
All, (hey Lou)

I got a PDP 11/23 at a hamfest in the same-ish configuration as smp, but just the computer box, no disk drives. I'll probably do the ROM upgrade as Lou suggests, I can burn extras.

I got to ODT on it last night, after scoping the serial pins to see if I really was getting serial out. After trying almost all the baud rates, I found it was 300 baud [maybe they had a modem on the console?]

I'll probably try to build the FPGA disk emulator discussed elsewhere as I have the 2-board RLxx disk boards.

Sorry for the buttinsky reply...

-Crawford
 
Crawford said:
I got a PDP 11/23 at a hamfest in the same-ish configuration as smp, but just the computer box, no disk drives. I'll probably do the ROM upgrade as Lou suggests, I can burn extras.
Click to expand...

Hi Crawford,

Thanks for butting in, the more the merrier!

When you decide to go ahead and do the ROM upgrade, I would be interested in obtaining a copy from you. No rush. I am in the very same boat as you, with only the computer, and I'm in the middle of getting a second serial I/O board, so I can attach the TU-58 tape emulator.

Anyway, once I have the tape emulator attached, I will then be looking for tape images to transfer into the PDP-11, so, if you are aware of anyplace to get some TU-58 tape image files, I would appreciate hearing about it. It seems that many folks have obtained them, or created them by using a PDP-11 emulator, or know someone who has done that, but no one seems to have them openly available for download anywhere that I have been able to find.

smp
 
smp said:
Hi Crawford,

Thanks for butting in, the more the merrier!

When you decide to go ahead and do the ROM upgrade, I would be interested in obtaining a copy from you. No rush. I am in the very same boat as you, with only the computer, and I'm in the middle of getting a second serial I/O board, so I can attach the TU-58 tape emulator.

Anyway, once I have the tape emulator attached, I will then be looking for tape images to transfer into the PDP-11, so, if you are aware of anyplace to get some TU-58 tape image files, I would appreciate hearing about it. It seems that many folks have obtained them, or created them by using a PDP-11 emulator, or know someone who has done that, but no one seems to have them openly available for download anywhere that I have been able to find.

smp
Click to expand...
I did that on my old 11/34 using a Unibus DL11. In fact I still have that board, but not the system. It worked quite well, besides being slow.
 
tradde said:
I did that on my old 11/34 using a Unibus DL11. In fact I still have that board, but not the system. It worked quite well, besides being slow.
Click to expand...

The big question for me is, do you still have access to the TU-58 tape images?
If so, would they be any good for use on my 11/23?
If not, do you know where I should go, or can you give me any pointers on how to proceed?

Thanks!

smp
 
smp said:
The big question for me is, do you still have access to the TU-58 tape images?
If so, would they be any good for use on my 11/23?
If not, do you know where I should go, or can you give me any pointers on how to proceed?

Thanks!

smp
Click to expand...
Someone sent me the pre-configured images I needed to create a TU58 "tape". I thought I would still at least have the message but
I can't find anything regarding it. But I was using it to read a preconfigured tape image to load to an RL02 which I had. It worked and I had RT-11
running on the 11/34 for awhile. It was not hard and I will continue to search for info about it for you.
 
We'll get some TU58 RT11 images made up for you, I've just been having a time with it. Apparently I'm going to have to use real hardware, as E11 crashes on TU58 access for me, and SIMH doesn't support TU58 currently.
 
glitch said:
We'll get some TU58 RT11 images made up for you, I've just been having a time with it. Apparently I'm going to have to use real hardware, as E11 crashes on TU58 access for me, and SIMH doesn't support TU58 currently.
Click to expand...

Hi Glitch,

Thanks very much! You are already doing a lot to assist me.

Just so you know, I tried playing with SIMH, and found that TU-58 was not supported, and I have seen others complain that TU-58 is not working well with E-11, so I did not try for one of the 30 day free trials there. I am hunting around a lot, but I just have not yet come up with something myself, yet.

Thanks very much, again, to you all for your great attention and support!

smp
 
Yeah, there seems to be very little in the way of non-XXDP TU58 images available. I'll have to see what's on the real TU58 cartridges we've got, but I think they're all diagnostics as well. You can definitely boot/run RT11 from TU58, it's just not fast!
 
Just throwing my hat in here again. I am also getting my 11/23 to work and I would also like a (and be very grateful for) TU-58 RT11 image. I will be using a second port on my SIGMA DLV11-J compatible card to connect to the TU58 emulator. I have 256Kb of memory so bigger images should work too.

I found instructions on this page about getting UNIX loaded: http://www.diane-neisius.de/pdp11/index_E.html So I will try that too.

Regards,
Vlad.
 
glitch said:
Yeah, there seems to be very little in the way of non-XXDP TU58 images available. I'll have to see what's on the real TU58 cartridges we've got, but I think they're all diagnostics as well. You can definitely boot/run RT11 from TU58, it's just not fast!
Click to expand...

TU-58 is too small to hold real DEC operating systems, except for XXDP the diagnostic monitor, and a really cut down version of RT-11 (altho this was more of a hobbyist thing, no real DEC PDP-11 user would have run RT-11 off a real TU-58 ).

TU-58's were mainly used for data files and distributing patches.
 
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