| 摘要 |
PURPOSE:To limit a service interruption to minimum by writing the content of a self system memory to an external memory by a preliminary processor and reading the content of a file in the self system memory when a difficulty is detected during the operation of both systems and one system is operated. CONSTITUTION:An external memory FMO is used as a system file and an external memory FM1 is used as a failure information collecting fie. During a normal operation, a central processing unit CC#1 of a present system and an internal memory MM#0 of the present system are in a condition of operation (ATC) and a central processing unit CC#1 of a preliminary system and an internal memory MM#1 of the preliminary system are in the condition of a standby (SBY). When both the systems are operated and an abnormal condition is detected and one system is operated, the unit CC#1 writes automatically the contents of the memory MM#1 to the memory FM1 and reads the contents of the memory FMO to the memory MM#1 and backs up the memory. |
