A processor controls an oscillation circuit such that a frequency of a clock signal is close to a reference frequency based on a frequency of a carrier wave of a standard radio wave and the frequency of the clock signal. In this manner, since the processor controls the frequency of the clock signal by using the carrier wave of the standard radio wave of which the frequency is managed with high accuracy, it becomes possible to improve accuracy of an internal time.

A processor controls an oscillation circuit such that a frequency of a clock signal is close to a reference frequency based on a frequency of a carrier wave of a standard radio wave and the frequency of the clock signal. In this manner, since the processor controls the frequency of the clock signal by using the carrier wave of the standard radio wave of which the frequency is managed with high accuracy, it becomes possible to improve accuracy of an internal time.