Registered: 19/05/1999
Posts: 3457
Loc: Palo Alto, CA
For this you do need special serial hardware so you can use it in multidrop mode - this is what a lot of car changer busses do.
I did come up with an actual protocol to run over the serial port when docked - the single character commands were just a debug thing which people started to use. The protocol is much more extensible and rather more useful :)