To enable normally reading data for initial setting at the time of resetting such as power-on.

A physical layer unit performs activation processing on the basis of a first reset signal to be given from a host, and generates a second reset signal in which the activation time is taken into consideration and outputs the generated signal to a data control unit. Also, the physical layer unit previously sets a waiting time in which the activation time of the data control unit to be activated on the basis of the second reset signal is taken into consideration, tries to read the data for initial setting in the storage unit of the data control unit after the waiting time elapses, and writes the data for initial setting which are read via a serial bus into a built-in data register.