Method for communication between a first station and a second station, and a controller and remote station using the communication method

An apparatus for communicating with at least one second station over a distribution medium, comprising:

• Means for providing an alternating power signal over the distribution medium, the alternating power signal comprising a plurality of communication symbols;
• and
• Control means arranged determine current draw in the alternating power signal to recover at least one further communication symbol from a second station.

An apparatus for communicating with a first station over a distribution medium, comprising:

• Means for receiving an alternating power signal comprising a plurality of communication symbols over the distribution medium, and for recovering the communication symbols therefrom;
• and
• Control means arranged to draw current from the alternating power signal in a sequence corresponding to at least one further communication symbol.

An apparatus for controlling a plurality of second stations connected to the apparatus by a distribution medium, the apparatus comprising:

• Means for providing power to the second stations via a distribution medium;
• and
• Control means arranged to provide a reference datum to the second stations and to instruct each second station to activate, each second station responsive to the instruction to activate at a prescribed offset from the reference datum.