Patent ID: 7487022

Claim:
A method of transmitting data between a central control device of a passenger protection system in a vehicle and at least one decentralized sensor unit, the sensor unit having a sensor for recording sensor measurement data, and the sensor unit being selectively operated in a normal operating mode wherein the transferred data contain sensor measurement data or in a test operating mode wherein the transferred data contain characteristic data of the sensor unit, and the method, in the normal operating mode and in the test operating mode, comprises: transferring data from the sensor unit as data packets comprising individual data bits; periodically outputting synchronization pulses with the central control device in order to request data packets; and always sending, from the sensor unit, the data packets respectively awaiting transmission to the control device after a most recent synchronization pulse; appending, in the sensor unit, an identifier to the data bits awaiting transmission by adding at least one identifier bit before the transmission to the central control device; and wherein the data packets in the normal operating mode have a different identifier than the data packets in the test operating mode, and the data packets of the normal operating mode are clearly distinguishable from the data packets of the test operating mode based on the relevant identifier.