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- 22
- 注册时间
- 2021-8-24
- 在线时间
- 3 小时
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void TIM3_PWM_Init(u16 arr,u16 psc)
{
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
//PB5配置PB5为复用输出
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //①时钟 TIM3 使能
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB|RCC_APB2Periph_AFIO, ENABLE); //使能PB端口时钟 //复用时钟使能 ①使能GPIO和AFIO复用功能时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
//设置该引脚为复用输出功能,输出TIM3 CH2的PWM脉冲波形 GPIOB.5
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5; //TIM_CH2 ->PB5
GPIO_InitStructure.GPIO_Mode=GPIO_Mode_AF_PP;//推挽复用输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure); //①初始化GPIO
GPIO_PinRemapConfig(GPIO_PartialRemap_TIM3,ENABLE); //设置TIM3_CH2重映射到PB5上。
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6; // TIM3_CH1 对应 PA6
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
//定时器TIM3初始化
TIM_TimeBaseStructure.TIM_Period=arr; //设置自动重装载寄存器周期的值
TIM_TimeBaseStructure.TIM_Prescaler=psc; //设置时钟频率除数的预分频值
TIM_TimeBaseStructure.TIM_ClockDivision=0; //设置时钟分割
TIM_TimeBaseStructure.TIM_CounterMode=TIM_CounterMode_Up; //向上计数
TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); // 初始化TIM3
//初始化TIM3 Channel1 PWM模式
TIM_OCInitStructure.TIM_OCMode=TIM_OCMode_PWM1; // 选择PWM模式1
TIM_OCInitStructure.TIM_OutputState=TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_Pulse = 500; // 初始占空比为 50%
TIM_OCInitStructure.TIM_OCPolarity=TIM_OCPolarity_High; //输出极性高
TIM_OC1Init(TIM3,&TIM_OCInitStructure); //初始化TIM3 OC1
TIM_OC1PreloadConfig(TIM3, TIM_OCPreload_Enable); //使能预装载寄存器
//初始化TIM3 Channel2 PWM模式
TIM_OCInitStructure.TIM_OCMode=TIM_OCMode_PWM2; // 选择PWM模式2
TIM_OCInitStructure.TIM_OutputState=TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_OCPolarity=TIM_OCPolarity_High; //输出极性高
TIM_OC2Init(TIM3,&TIM_OCInitStructure); //初始化TIM3 OC2
TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Enable); //使能预装载寄存器
TIM_ARRPreloadConfig(TIM3, ENABLE);
TIM_Cmd(TIM3, ENABLE); //⑤使能TIM3
}
extern u8 TIM5CH1_CAPTURE_STA; //输入捕获状态
extern u16 TIM5CH1_CAPTURE_VAL; //输入捕获值
int main(void)
{
u32 temp=0;
delay_init(); //延时函数初始化
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); //设置NVIC中断分组2
uart_init(115200); //串口初始化波特率为115200
LED_Init(); //初始化与LED连接的硬件接口
TIM3_PWM_Init(899,0); //不分频。PWM频率=72000/(899+1)=80Khz
TIM5_Cap_Init(0XFFFF,72-1); //以1Mhz的频率计数
while(1)
{
delay_ms(10);
TIM_SetCompare2(TIM3,TIM_GetCapture2(TIM3)+1);
if(TIM_GetCapture2(TIM3)==300) TIM_SetCompare2(TIM3,0);
if(TIM5CH1_CAPTURE_STA&0X80)//成功捕获到了一次上升沿
{
temp=TIM5CH1_CAPTURE_STA&0X3F;
temp*=65536;//溢出时间总和
temp+=TIM5CH1_CAPTURE_VAL;//得到总的高电平时间
printf("HIGH:%d us\r\n",temp); //打印总的高点平时间
TIM5CH1_CAPTURE_STA=0; //开启下一次捕获
}
}
}
DS0指示灯不闪//

请大师级别指点下,问题所在
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