| 摘要 |
PURPOSE:To isolate the cause for the occurrence of abnormalities with ease by providing a specified number of storage areas which can store engine operating conditions, on a RAM whereby enabling the memory holding of the history of engine operating conditions within a period of time from the occurance of abnormalities. CONSTITUTION:When electric power is turned on, an address counter is set first to a head A0 out of a plurality of memory areas A0-An of a RAM 3 through a CPU 1. Subsequently, after a timer has been cleared away, the data for engine operating conditions is written into a storage area of an address directed by the address counter. Then a judgement is made as to whether the timer passes a predetermined time or not, and then after the predetermined time has passed, a judgement is made as to whether abnormalities occur or not by means of a self-diagnosis. In this state, when no abnormality is found, the data is written in order into the storage area every the predetermined time. On the other hand, when abnormalities are found, the data is prohibited from being written on and after that time, and the address of the storage area, to which the last data has been written, is written into the other area on the RAM 3 for keeping it in storage. |
