| 摘要 |
PURPOSE:To facilitate processing in a fixed fault by dividing a data receiving and passing area into a main and an auxiliary area and indicating which area is used, and allowing hardware to access the indicated area automatically. CONSTITUTION:If a fixed fault occurs to the data receiving and passing area CiA, a CPU program transfers necessary data based upon an instruction to the auxiliary CiA and sends out a switching signal indicating the switching of the CiA to send execute I/O signal (XiO signal) to turn on. When a CHP receives the signal XiO, a switching signal for switching the CiA is sent out in case of a fault and the instruction is interrupted as instruction processing damage. If the CPU detects a fault when receiving an accept signal, instruction processing damage processing is performed and the switching signal is sent out. Consequently, the subsequent actuation is performed by using the CiA having no fault. |
