Patent ID: 8284035

Claim:
A method for conveying information from a controller to at least one slave unit using a single wire referenced to an alternating current (AC) power supply, the method comprising: generating, within the controller, a control signal based upon the information, the control signal having a high voltage and a low voltage, the high voltage being greater than a voltage midpoint of the AC power supply and the low voltage being less than the voltage midpoint, the voltage midpoint being substantially midway between potentials of power lines of the AC power supply; conveying the control signal through the single wire to each of the at least one slave unit; generating, at each of the at least one slave unit, a comparison voltage representative of the voltage midpoint by dividing substantially midway the potentials between the power lines of the AC power supply; comparing, at each of the at least one slave unit, the control signal to the comparison voltage to determine low and high states of the control signal, the low and high states representing the information.