摘要 |
An edge signal extractor generates an edge signal according to a sound wave generated for controlling the electronic appliance. According to the edge signal, an edge pulse generator generates an edge pulse. If a predetermined number of such edge signals are generated, a controller displays, on a display of the electronic appliance, one of menu images associated with control operations of the electronic appliance in an active state. The controller alternately displays, in an active state, the menu images on the display at predetermined intervals. When the edge pulse is generated, the controller carries out the control operation associated with the presently displayed menu image with respect to an electronic appliance. |