| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a facsimile device which can determine the hook state of an external phone correctly by voltage detection even if the destination of a telephone line is changed and thereby the line voltage is changed. <P>SOLUTION: A facsimile device 10 comprises a diode bridge 14 connected with a telephone line 3, a changeover switch 15 which changes over an external phone 4 between a connection route 1 connected to the pre-stage of the diode bridge 14 and a connection route 2 connected to the post-stage of the diode bridge 14, a silicon DAA 13 (a voltage detection unit 21) which detects a voltage applied to the external phone 4 from the telephone line 3, and a control unit 11 which controls the changeover switch 15 to change over the connection route 1 and the connection route 2, and performs change over determination processing for determining whether the external phone 4 is on-hook or off-hook from the comparison result of the line voltage detected on the connection route 1 by the voltage detection unit 21 and the line voltage detected on the connection route 2 by the voltage detection unit 21. <P>COPYRIGHT: (C)2012,JPO&INPIT |
