| 摘要 |
PURPOSE:To hold a transmission function by a left normal part in case of control station fault or transmission line disconnection. CONSTITUTION:Control stations ST1-ST5 are connected through a transmission line, and ST5 out of them functions as master control station MST. Two-way data transmission as well as repeating operation are possible in respect to ST1-ST4. MST transmits data only in one direction and does not perform repeating of receiving data. For example, if ST1 is faulty, MST receives data only in the (1) side, and information which MST issues spontaneously is disconnected. Though a faulty position can be found by combination of the capabilities above, MST performs two-way transmission after anomaly decision and discriminates states of stations adjacent to the faulty control station, so that transmission function between transmission lines can be held by left normal control stations. |
