| 摘要 |
PURPOSE:To provide a malfunction preventing for on-vehicle microcomputer so as to prevent the microcomputer from disabling recovery from a standby mode. CONSTITUTION:The output voltage of a power supply circuit 1 corresponding to the ON/OFF of an IGN switch is impressed to a terminal NMI. An edge detecting means 3-1 detects the rise/fall of the terminal NMI. When the fall is set by a detected edge setting means 3-2, a level detecting means 3-4 detects the level of the terminal NMI according to a voltage at a terminal To before a control means 3-3 sets the standby mode corresponding to the detection. The setting means sets the fall corresponding to the rise detection, and the rise is set corresponding to the fall detection and the L level detection of the level detecting means 3-4. Even when the fall is detected, corresponding to the detection of an H level, the control means recovers the normal operation. |
