Instead, he has taken Tim's patch, and modified the pdp11_dl.c code so that
the address and the carrier detect can be set at runtime to behave like a DC11.
Here are the simh.cfg lines you need to add once you apply the KL.diff patch
to Simh:
set ttix en ; Enable DC/DL-11 device
set ttix lines=8 ; We want 8 serial ports
set ttix address=17774000 ; Set the address to be a DC-11
set ttix carrier=dc ; Turn on the DC-11 carrier detect bit
set ttox 7b ; Set output to be 7-bit, lowercase
att ttix 5555 ; Attach serial ports to telnet 5555