Energy distribution and communication system and method utilizing a communication message frame for a multi-device vehicle occupant protection system

Abstract

A system (,) conveys energy and communication between a master (,) and a plurality of slaves (,), via a bus (,). A power/voltage transmitter (,) of the master (,) provides electrical energy, having a voltage, onto the bus (,) to power the slaves (,). The power/voltage transmitter (,) adjusts voltage past a predetermined threshold to provide a message frame and modulating voltage during the message frame to convey messages to the slaves (,). Voltage receivers (,), at each slave (,), detect the voltage modulations to discern messages from the master (,) during the message frame. Current transmitters (,), at each slave (,), modulate current during the message frame to convey messages to the master (,). The current transmitters (,) utilize the modulation of voltage of the electrical energy to clock modulation of current. A current receiver (,) of the master (,) detects current modulations to discern messages from the slaves (,). Preferably, the system is part of an occupant protection system (,), and the slaves (,) include an occupant protection device.