| 摘要 |
PROBLEM TO BE SOLVED: To provide a controller for an industrial equipment which can predict a degradation state of a shielded wire connected to the industrial equipment. SOLUTION: A voltage of a communication line 30 during a bus open period is fixed to a first intermediate voltage value and a voltage of a communication line 31 is fixed to a second intermediate voltage value that is lower than the first intermediate voltage value by a predetermined value or more by voltage fixing means 70. When the voltage of the communication line 30 is higher than the voltage of the communication line 31 by the predetermined value or more, a differential receiver 66 outputs a digital signal representing "1" and when the voltage of the communication line 30 is lower than the voltage of the communication line 31 by the predetermined value or more, it outputs the digital signal representing "0". When the digital signal representing "0" is output from the differential receiver 66 during the bus open period, a control circuit 25 determines that the noise is superimposed on the communication lines 30 and 31. COPYRIGHT: (C)2010,JPO&INPIT
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