DL10 documentation

Noel Chiappa jnc at mercury.lcs.mit.edu
Tue Jan 9 07:36:09 CST 2018

    > From: Lars Brinkhoff

    > Richard Cornwell wants to implement DL10 for his KA10/KI10 simulator,
    > but he doesn't have any documentation for it.  Any leads?

Well.... The "decsystem10 System Reference Manual (DEC-10-XSRMA-A-D) -
available online:


has a definition for the -10 side of the interface on pages C-21 and
following (page 365 of the PDF). It just specifies the I/O instructions and
bits, there's no description of how it works.

Still, that will help understand code that uses it; the complete ITS code is

I couldn't find anything on the PDP-11 side of the interface; ITS' IOELEV >
does define a "DLXCSR", and the bits in it, but ... it seems to be a memory
location, not a register?

The DL10 was used in two DEC system products, the DC76 Asynchronous
Communication System, and the DN87 and DN87S Universal Communication System
Front Ends. I couldn't find any documentation on the former, but complete
prints for the latter are available:


It includes a complete set of prints for the DL10. From this, and also from:


it appears that the PDP-11's connected to the DL10 have a special console
which has a cable which goes to the DL10 which allows the PDP-10 to start and
stop the PDP-11; the PDP-11's UNIBUS runs into the DL10 and is plugged into
the DL10.

Anyway, it's going to be some hard work to create a DL10 programming manual
from those dribs and drabs, but there is enough info there that it can be


More information about the cctalk mailing list