/***********************************************************
通過定時器TIM3產生間隔時間爲1秒的中斷,在中斷響應
函數中控制LED發光二級管,實現流水燈效果
***********************************************************/
void TimeInit()
{TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
//打開相應的時鐘
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);
//清除TIM3的中斷待處理位:TIM 中斷源
TIM_ClearITPendingBit(TIM3,TIM_IT_Update);
//設置定時器TIM_TimeBaseInit初始化定時器的時鐘基數
TIM_TimeBaseStructure.TIM_Period = 2000 -1;
TIM_TimeBaseStructure.TIM_Prescaler = 36000 -1;
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM3, & TIM_TimeBaseStructure);
//使能指定的TIM中斷
TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE );
//使能TIM定時器
TIM_Cmd(TIM3, ENABLE);
//設置NVIC
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);
NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}
中斷函數編寫
//TIM3中斷響應函數
void TIM3_IRQHandler(void)
{
static int i = 0;
//判斷是否發生中斷
if(TIM_GetITStatus(TIM3, TIM_IT_Update) == SET)
{
//清除EXTI線路掛起位
TIM_ClearITPendingBit(TIM3,TIM_IT_Update);
GPIO_Write(GPIOC, (u16)~(0x01<<i++));
if(8 == i) i= 0;
}
}