I am happy to report the software for the PiDP-11 I/O Expander is finally complete! I've posted installation instructions, a brief theory of operation, and usage on GitHub along with a new release tarball which contains an updated SIMH.

I have to admit, It's been quite satisfying to finally program external hardware using the switch register. This should hopefully be everything that is needed for folks to begin writing device drivers in their OS of choice.