A clock transfer circuit receives input data synchronized with a first clock, and outputs, as output data, data synchronized with a second clock having a frequency different from that of the first clock. A write address controller is operating according to the first clock, and provides a write address to a memory. A read address controller is operating according to the second clock, and provides a read address to the memory. A cycle comparator compares the cycle of a predetermined event between the input data and the output data. Based on such a comparison result, the clock adjuster adjusts the frequency of the second clock.