| 摘要 |
PURPOSE:To exclude a relay contact which is necessary to switch the connection between a back-up muCPU and other muCPU by using a communication circuit to transfer the information needed for back-up. CONSTITUTION:If a fault arises at an arithmetic control part ALUi of a muCPU of a certain station at the time of operation, a signal SA2 showing the generation of the fault is transmitted to a communication interface part ICi. The part ICi does not transmit the signal SA2 to an error accepting part but transmits it to a communication circuit CO via a transmission part like a normal signal. Thus other stations, an operator console POC and a back-up muCPUb fetch the signal SA2 through their reception parts respectively and understand that a fault arises at the muCPUi. At the same time, the control part of the part ICi of the faulty station changes the control contents in reply to the singal SA2. Then the information is transferred between the muCPUb and the faulty station via the circuit CO, and a back-up operation is carried out. |
