| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enable detection of a remote control function and a speaker on/off function by using one terminal in a device in which either of speaker reproduction and headphone reproduction is selectively usable. <P>SOLUTION: A body 1 of an audio player is connected with multiple resistors R1 to Rn (n is a natural number) connected in series to a terminal B; multiple operation keys SW1 to SWn connected between the resistors R1 to Rn and a ground; and a headphone remote-control unit 2 having a resistor RA connected between the terminal B and the ground. The body 1 has a terminal A connected with the terminal B; a resistor RC for pull-up of the terminal A; a comparator 4 for detecting voltage change at the terminal A; a speaker control section 6 for muting an audio signal that is outputted to a speaker 8 according to output from the comparator 4; and an A/D key input section 3 for decoding voltage change at the terminal A and generating operation data. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
