@marcin_mfm oh, my network uses a linux router, that is the gateway between the internet and my two networks, each of which just use switches. I have about 12 computers that operate 24/7 (router, jukebox, home automation, workstation, etc)

happy to see that it did work! here's a video of it in action: https://f.sakamoto.pl/PO_bell103.webm

this will *also* get a blogpost sometime in the near future. I'm still considering trying TCP/IP, but it would be ungodly slow at 300baud :p

(also, yes, I have revoked the token visible in the video)