| 摘要 |
PURPOSE:To search fault causes from the state of data and to facilitate the fault recovery of a device by preventing the data in a RAM from being erased by checking the data destruction of the RAM with the program operation of a CPU and immediately stopping the program operation after outputting an alarm when the data destruction is detected. CONSTITUTION:A ROM 3 stores the control program of this device or fixed data required for the operations. A RAM 4 is a nonvolatile memory and stores data to be fixedly set corresponding to each device in advance or data to be arbitrarily registered by a user as needed. When the power source of the device is turned on, the data destruction of the RAM 4 is checked by the program operation of a CPU 6 and when the data destruction is detected, the program operation is immediately stopped after error display and alarming so as to prevent the stored data in the RAM 4 from being erased. Thus, the executed abnormal operation can be estimated from the state of change of the data in the RAM 4, and the cause of the destruction can be searched. |
