PURPOSE: To reduce the burden of software by manually setting a control data value to a control data set part and generating an interrupt signal to a CPU to perform the control processing in the case of coincidence between this control data value and the value of input data.

CONSTITUTION: A control data set part 2 consisting of plural switches and a data comparing part 3 consisting of an exclusive OR circuit are provided, and a control code or the other code is discriminated by hardware. When the value manually set to the control data set part 2 and the value of input data coincide with each other, the interrupt signal is generated from the data comparing part 3 and a CPU 6 is interrupted to perform the control processing, and thereby, the control code or the other code is discriminated by hardware. Thus, the burden of software is reduced, and transmission is performed at a high speed through the data volume is increased, and the control code is easily changed.