| 摘要 |
PURPOSE:To restore a main storage device rapidly and accurately by monitoring the control information on the main storage device in a stand-by system control unit through CPU in the same unit and by changing information transfer systems via CPU in an in-use system control unit when a fault occurs. CONSTITUTION:All control information 8' in main storage device 7' of stand-by system control unit 5' similar to in-use control unit system 1' of an electronic switching equipment, etc., is monitored by CPU6' of unit 5' and faults are all detected and never latent. On detecting a fault, CPU6' reports that to CPU2' of unit 1' via information transmission line 11' and then CPU2' changes information transfer path 10' over to information transfer path 13'. Thus, control information from external storage device 9' is rerestored in device 7' via CPU6' to correct the fault. This constitution restores the main storage device rapidly and securely without any latent fault. |
