Patent ID: 8825220

Claim:
A system for controlling an in-vehicle device, comprising an in-vehicle device and an electronic control unit, the electronic control unit generating control signals to control the in-vehicle device and transmitting the generated control signals to the in-vehicle device via a wire harness, the in-vehicle device is provided with a semiconductor integrated circuit and a semiconductor memory circuit, wherein the semiconductor integrated circuit includes a functional operation control unit, a memory read control unit and a majority determination calculating unit, the functional operation control unit being provided for outputting control signals to control functional operations, the semiconductor memory circuit includes channels and storing plural sets of n-multiplexed information pieces of setting information which are necessary to perform the respective functional operations in the channels in a channel unit, where “n” is an odd number equal to or greater than three, the electronic control unit is provided with a designation signal generation unit connected to the memory read control unit via the wire harness, the designation signal generation unit outputting static designation signals as the control signals to the memory read control unit so as to generate address signals, the n-multiplexed pieces of setting information being read from the channels of the semiconductor memory circuit according to designation by the address signals and being output to the functional operation control unit, and the majority determination calculating unit receives the read n-multiplexed information pieces of setting information and determines information pieces to be output to the functional operation control unit of the semiconductor integrated circuit by majority determination logic, the majority determination calculating unit comparing the data values of the n-multiplexed information pieces with each other and deeming the majority of the data values as correct data values to output the data of the majority to the functional operation control unit so as to select the functional operations.