PDP-11/44 mystery card

[Pontus Pihlgren]

Hi

I've acquired two PDP-11/44 and have just now gone throught the list of 
cards in the cpu-boxes and the spares. Here is a list:

http://www.update.uu.se/~pontus/slask/11-44-kort.txt

Nothing special, I've used the field guide to identify most cards. I've 
only marked one card of each kind.

There is two cards connected with ribbon cables that I can't identify. 
They are made by Data Management Labs in San Jose and are labled DML 750 
Board A and Board B. There are some numbers as well (in no particular 
order)

980-8043
710-1921-001

There are some bitslice chips and a whole bunch of roms. Anything that 
rings a bell with anyone?

Also I wonder what the 
"M7251   KG11-A      U   Network interface XOR and CRC block check option"
"M3110   DRCSA       U   Protocol assist #1 w/special character check and CRC (DEC/DLC/DRCSA)"
"M3111   DRCSA       U   Protocol assist #2 w/special character check and CRC (DEC/DLC/DRCSA)"

are used for?

Cheers,
Pontus