KEY INFORMATION GENERATION DEVICE, KEY INFORMATION RECOGNITION DEVICE, AND KEY INFORMATION GENERATION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a key information generation device capable of simultaneously transmitting key information pieces with a simple configuration without increasing the number of terminals.SOLUTION: A key information generation device generates a key signal SK that is obtained by superimposing a waveform, which has a first duty ratio corresponding to first information and is obtained by pulse width modulation at a second frequency higher than a first frequency, on voltage that is an offset voltage V1 according to a pressed first key 110 out of a plurality of keys 110 and has the first frequency of 0 Hz or higher.