I am assuming home alarm systems use a serial interface of some type to connect the keypad to the alarm panel. Does anybody have any experience interfacing a BX anywhere to an alarm system. I more specifically want to connect a wireless expander to my BX that is designed to connect to the 4 wire cable that runs from the keypad to the panel. Because the expanders go from 1 to 96 zones on 4 wires I am assuming it is two wires for power and two for data. Any experience or ideas?