| 摘要 |
PURPOSE:To improve the profitability of a signal transmission system by allowing a transmitter to raise a potential corresponding to the affirmative response of negative logic if a fault takes place in a signal transmission system transmitting a binary signal. CONSTITUTION:A supervisory signal line 8 is provided between an alarm detection section 1 and an alarm control section 6 and the alarm detection section 1 transmits a supervisory signal with negative logica to a transmission end of a supervisory signal path 8 via an inverting circuit 7. It is possible for the alarm control section 6 to supervise a faulty state caused to any of the alarm detection section 1 and the supervisory signal line 8 based on the supervisory signal transmitted via the supervisory signal line 8 to stop a display based on an alarm signal when the faulty state is detected. Thus, it is not required to provide any special circuit to detect a falt. |
