I just realized that one item may cause a difference in the solution -- this bus also has a Xantech RS232IR putting data onto it, and the bus also controls a Xantech RT8 router. So it is not just the RX77 and LEDs, it is a bus running active Xantech components.
A good answer is easier with a clear question giving the make and model of everything. "The biggest problem in communication is the illusion that it has taken place." -- G. “Bernie” Shaw
