Receiving device and receiving method

A receiving device, comprising:

• an equalizer circuit shaping a waveform of an input signal according to an equalizer coefficient being set;
• a CDR (clock data recovery) circuit recovering, from the input signal being shaped by the equalizer circuit, received data represented by the input signal and a clock signal which indicates a determination timing of the received data;
• a number counting part counting, in a range of detection having a predetermined width, a sampling result obtained by sampling the input signal being shaped by the equalizer circuit at the determination timing;
• a zone scanning part scanning the range of detection in a scanning zone including a variation range of a voltage value of the input signal;
• a coefficient altering part altering the equalizer coefficient set to the equalizer circuit;
• a peak detecting part detecting a peak value of a number of appearances of the sampling result based on a change in a counting result obtained by the number counting part according to the alteration of the equalizer coefficient and the scanning of the range of detection;
• and
• a coefficient specifying part specifying the equalizer coefficient being set to the equalizer circuit when detecting the peak value in the peak detecting part as a first coefficient.