STM32F072产生不了PWM

1万 · 2021-5-9 21:54

int main(void)
{
      RCC_ClocksTypeDef  RCC_Clocks;
      uint32_t sys;

      RCC_HSI_Configuration();
      UART1_Configuration();//波特率9600
      LED_Init();
      TIM1_PWM_Init(23,1);

      while (1)
      {
            Clr_LED_1;
            Clr_LED_2;
            //TIM1_Set_PWM();
            //Clr_LED_4;
      }
}

void TIM1_PWM_Init(uint16_t arr,uint16_t psc) //产生pwm
{
      GPIO_InitTypeDef GPIO_InitStructure;
      TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
      TIM_OCInitTypeDef TIM_OCInitStructure;


      RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
      RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOF, ENABLE);//使能GPIO外设和AFIO复用功能模块时钟使能

      GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
      GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
      GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
      GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
      GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP ;
      GPIO_Init(GPIOF, &GPIO_InitStructure);

      GPIO_PinAFConfig(GPIOF, GPIO_PinSource0, GPIO_AF_1);


      TIM_TimeBaseStructure.TIM_Period = arr;//设置在下一个更新事件装入活动的自动重装载寄存器周期的值
      TIM_TimeBaseStructure.TIM_Prescaler =0;//设置用来作为TIMx时钟频率除数的预分频值
      TIM_TimeBaseStructure.TIM_ClockDivision = 0;//设置时钟分割:TDTS = Tck_tim
      TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;//TIM向上计数模式
      TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;
      TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);//根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位

      TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;//PWM模式1
      TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;//正向通道有效
      TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;//反向通道无效
      TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCPolarity_Low;
TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;
TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;
      TIM_OCInitStructure.TIM_Pulse = 100;

      TIM_OC1Init(TIM1,&TIM_OCInitStructure); //通道1
      TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);

      TIM_CtrlPWMOutputs(TIM1,ENABLE);

      TIM_ARRPreloadConfig(TIM1, ENABLE);//使能TIMx在ARR上的预装载寄存器
      TIM_Cmd(TIM1, ENABLE);//使能TIMx外设
}

2万 · 2021-5-9 21:57

如果其它配置【时钟、GPIO、TIM外设时钟]都配好了，你现在ARR=23，而CCR又等于100，此时输出的是固定的低电平

1万 · 2021-5-9 21:59

结合你当前极性选择

1万 · 2021-5-9 22:03

你把ARR调整大点，或者把CCR调得比Arr小，你看看还有无波形输出？

1万 · 2021-5-9 22:10

应该是我用的IO口不对，定时器1复用不在PF0上

1万 · 2021-5-9 22:13

应该是我用的IO口不对，定时器1复用不在PF0上

2万 · 2021-5-9 22:16

强烈建议使用STM32CUBEMX进行配置，就可以绕开基本的GPIO/时钟这些配置错误。

1万 · 2021-5-9 22:18

void TIM2_PWM_Init() //产生pwm
{
      GPIO_InitTypeDef GPIO_InitStructure;
      TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
      TIM_OCInitTypeDef  TIM_OCInitStructure;

      float TimerPeriod = 0;
      uint16_t Channel1Pulse = 0, Channel2Pulse = 0, Channel3Pulse = 0, Channel4Pulse = 0;

      /* GPIOA Clocks enable */
      RCC_AHBPeriphClockCmd( RCC_AHBPeriph_GPIOA, ENABLE);

      /* GPIOA Configuration: Channel 1, 2, 3 and 4 as alternate function push-pull */
      GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;
      GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
      GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
      GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
      GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP ;
      GPIO_Init(GPIOA, &GPIO_InitStructure);

      GPIO_PinAFConfig(GPIOA, GPIO_PinSource2, GPIO_AF_2);


      /* TIM1 clock enable */
      RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2 , ENABLE);

      /* Time Base configuration */
      TIM_TimeBaseStructure.TIM_Prescaler = 48-1;//预分频值
      TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
      TIM_TimeBaseStructure.TIM_Period = 500000;  //自动重装载值
      TIM_TimeBaseStructure.TIM_ClockDivision = 0;
      TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;

      TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

      /* Channel 1, 2, 3 and 4 Configuration in PWM mode */
      TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
      TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
      TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
      TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;//设置输出极性
      TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;
      TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;
      TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;

      TIM_OCInitStructure.TIM_Pulse = 100000;  //占空比时间
      TIM_OC3Init(TIM2, &TIM_OCInitStructure);


      /* TIM1 counter enable */
      TIM_Cmd(TIM2, ENABLE);

      /* TIM1 Main Output Enable */
      TIM_CtrlPWMOutputs(TIM2, ENABLE);

}