MAME will emulate several terminals. Among them is the vt240.

Here are my links for roms and docs:

http://www.bitsavers.org/pdf/dec/terminal/

https://github.com/larsbrinkhoff/terminal-simulator/issues/1

https://www.mail-archive.com/simh@trailing-edge.com/msg09086...

https://forums.bannister.org/ubbthreads.php?ubb=showflat&Num...

https://simh.trailing-edge.narkive.com/qgzCvrl8/dec-vt-emula...

I have a bunch of PDFs in along with this, and a vt240.zip that must have come from one of the above.

I also used this command line call to get the terminal running with "bitbanger."

  mame -rp . vt240 -window -nothrottle -host null_modem -bitb socket.localhost:2323

Back in college I ended up rooming with a bunch of unix neck beards and we used a vt320 as our "house control system." It controlled a rack in the basement hooked up to sound systems, tv remote controls for the living room entertainment systems which included a 70in crt monitor that played movie rips from network storage. Fun times.

I love old terminals and I still have a VT520 which is still very practicable, it can do up to 115200 instead of rhe VT-100's 9600.

But most programs ignore termcap these days which is a huge issue. Running stuff through tmux helps but it's not ideal.

You can put two of these back to back with the transmit and receiver wires crossed, and type straight from one to the other. Did this as a kid to chat with my little sister in another room.

Every now and then I look for a vt320 from my university days. Still miss the smell of hot dust on CRT electron guns.