| 摘要 |
PURPOSE:To prevent the substantial processing capability of a communication processing device from being deteriorated by providing a transmission line supervisory device to both ends of a transmission line. CONSTITUTION:The transmission line supervisory devices 1, 2 are connected to both ends of a common transmission line 3 and a fixed telegraphic message is transmitted to the communication processing device 6 having a function supervising the transmission line at each prescribed time from the transmission line supervisory devices 1, 2. The communication processing device 6 supervises the transmission line by checking whether or not the fixed telegraphic message is received at each prescribed time. Thus, the substantial processing capability is prevented from being deteriorated by releasing the communication processing device from the supervision of transmission line. |
