US Patent 7424351 Control unit and data transmitting method

A control unit receives a data request signal transmitted from a data recording apparatus, and then transmits a control parameter, which corresponds to the data request signal, out of control parameters used to execute control of a vehicle to the data recording apparatus. In this case, a transmission state of a transmitting section at a time of shutdown is stored as a communication history. Therefore, when the communication history is stored in a storing section, the transmission state at the time of shutdown is restored in a starting process executed after a power supply is turned ON, based on the read communication history.