| 摘要 |
PURPOSE:To eliminate unnecessary holding of a line or transmission of signal, by interrupting or completing the communication procedures, when a polarity change of a DC circuit of a telephone line during the communication of facsimile is detected. CONSTITUTION:An opposite terminal is called for the facsimile communication, the response of the opposite terminal is confirmed and a communication SW of the facsimile device is depressed to control a CML relay 11 from a device control section so as to connect lines L1, L2 to an line connecting circuit 13 and a polarity detecting circuit 12, and the transmission/receiving operation of a control signal is transferred to a phase B with a MODEM section 14. The polarity detecting circuit 12 in this case detects the polarity of a DC circuit of the lines L1, L2 and outputs to a polarity change detecting circuit 16. If a failure of the receiving side is generated and the change in the DC circuit is given to the transmission side, the change is outputted to the polarity change detection section 16, where the presence of the polarity change is checked, and the control of interruption of ending is executed at a facsimile procedure control section 17. |
