A ballast for use in a multi-ballast lighting system wherein the ballasts are coupled together by a digital communication network. The ballast comprises a power circuit portion for providing an electrical current to power a lamp. The ballast further includes a sensor input circuit for receiving at least one sensor input from a sensor device, a processor receiving an input from the sensor input circuit and providing control signals to control the operation of the ballast, and a communication port coupled to the processor and to the communication network for exchanging data. The ballast processor is operative to receive a serial data that has a portion defining whether the message is in a first or a second format, the first format comprising a DALI standard format and the second format comprising a format providing extended functionality. The ballast processor is capable of processing messages in either the first or second formats.