| 摘要 |
PROBLEM TO BE SOLVED: To prevent the mis-operation by a noise on a signal line for connecting between CPU and an outside memory by stopping the communication between a microprocessor and the outside memory in a term in which the generation of a noise is expected. SOLUTION: The timing of the generation of a noise can be estimated accurately in a control object controlled by a microcomputor. For example, in the case of the ignition device for an internal combustion engine, an ignition noise is generated when the high voltage for ignition is generated in the secondary coil of an ignition coil at an ignition time. As the term of the generation of the ignition noise is nearly constant, the time of the disappearance of the ignition noise is found out by an actual measurement and the communication between the microprocessor 3 and the output memory 4 is stopper during the term from the time slightly before than the timing of the generation of the ignition noise to the time slightly after than the time of the disapearance of the ignition noise. Thereby, the misoperation by the ignition noise on the signal line 5 can be prevented. |
