| 摘要 |
PURPOSE:To eliminate the need for a centralized control station and to attain the switching of a redundant system and the detection of failures at a waiting side, by providing a timer to each station of loop connection and performing communication function control. CONSTITUTION:A signal on a line 2 is fetched into a buffer BUF via a receiver R in which a switch S1 is turned on and the content of the BUF is transmitted to the line 2 via a transmitter T in which a switch S2 is turned on. Through the operation of the S1, S2, a communication signal is transmitted laterally between two systems in a specific communiction station 1i, and longitudinally between the same systems in other stations. A timer provided to each station is set at different time and a new time is reset to the timers at the normal reception of communciation frame. At time-up, each station starts the transmission of a specified frame by a controller C. As a result, the control at the system start and the system disconnecting control at failures are performed. |
