| 摘要 |
In indirectly controlled tele-communications exchanges duplicate central control units (V1,V2) operate alternatively, one operational while the other is on stand-by, control stores (S1c, S2c) associated with the control units being arranged for storing semi-permanent information which can be modified by means of inputs via an operating device (B) or subscriber stations (Tn). A background store (H) is provided to store the already modified information, the control stores (S1c, S2c) are arranged to receive information respectively from the operating device (B) and subscriber station (Tn) and interchange between the stores S1c, S2c, H) of modified information takes place at least by each changeover of operational control unit (V1,V2). Modification of information for a control store may take place in duplicate, a comparison of modification results made and non-identity used to reset the modifying store with the initial information by means of the other stores as well as giving an alarm. <IMAGE> |
