Qbus card in CD Opps

[wa2flq]

Hi all,

I powered up an old rack I had which has a 11/23Plus badged H9276A Backplane (running a 11/73 actually) I booted RT11 off my RL02 packs.
Everything was fine. After I powered it off, I took a look at the backplane and noticed it had a M8029 (RX02-half height) in the CD slot.

I didn't smell any magic smoke :bomb:, but was wondering if I had damaged it but having it in a CD Bus slot, as opposed to a QBus slot.

Anyone remember the bad things this would do? or have pinout of the CD wiring I could compare to the normal QBus for Power and ground?



Thanks!
JSW

 

[gslick]

The H9276 backplane C-D interconnect diagram is on page 386 of the PDP-11 Microcomputer Interfaces Handbook 1983-84 available here:

http://www.bitsavers.org/pdf/dec/qbus/EB-23144-18_QbusIntrfs_1983.pdf

I think the +5 and GND pins are the same on the Q22 AB half of the backplane as on the CD half.

Unless you had another quad width Q22/CD card directly above or below the dual width card the CD interconnect most likely did not connect the dual width card to anything that would cause any damage to it.

You would probably not be so lucky if you installed a quad width Q22/CD card (for example an M8190 KDJ11-B or M8637 MSV11-J) into a Q22/Q22 backplane slot.

-Glen

 

[wa2flq]

Thanks for the link.

Is there cross references of Quad cards that indicates which are Q22/Q22 vs Q22/CD compatible?

JSW

 

[Roe]

Generally, the user manual for the card describes the requirements, in the "installation" section...

 

[gslick]

Is there cross references of Quad cards that indicates which are Q22/Q22 vs Q22/CD compatible?

Here is a short list of quad width Q-Bus cards that should only be installed in Q/CD slots and not in Q/Q slots. I'm sure this list is not complete.

M7061 VSV11
M7062 VSV11
M7064 VSV11

M8013 RLV11
M8014 RLV11

M8190 KDJ11-B
M8637 MSV11-J

M7606 KA630
M7607 MS630-A
M7608 MS630-B
M7609 MS630-C
M7620 KA650
M7621 MS650-A
M7622 MS650-B
M7624 KA640
M7625 KA655
M7626 KA660

 

[wa2flq]

That's a good beginning, as its jogging my memory as to the type of Q-Bus cards to look out for..

Thank you!