Tinkertoys

I haven't figured it out, but I have messed around a bit. You mention an RJ11 socket, so I think you must be looking at a Lite Leader system - is that right? I am looking at Balboa GS systems, with 8-pin RJ45 plug. I don't have any experience with this type of engineering, but I have friends who know more than me, and who lent me a Bus Pirate. I think it's UART. I'm going to keep playing with it, and I would be interested to share information.