void ExterLineInterrupt(void) {     EXTI_InitTypeDef EXTI_InitStructure;     EXTI_DeInit();     EXTI_StructInit(&EXTI_InitStructure);        EXTI_InitStructure.EXTI_Line = EXTI_Line16;     EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;     EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;     EXTI_InitStructure.EXTI_LineCmd = ENABLE;     EXTI_Init(&EXTI_InitStructure); } 把外部中断触发方式改下，改成上升触发，这个有点反。