关于STM32的PWM输出问题

只看该作者 · 2020-10-31 17:21

本帖最后由 taborguo 于 2020-10-31 17:26 编辑

void TIM1_Mode_Config(void)
{
      TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
      TIM_OCInitTypeDef TIM_OCInitStructure;
      TIM_BDTRInitTypeDef TIM_BDTRInitStructure;
      RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);

      /* Time base configuration */
      TIM_TimeBaseStructure.TIM_Period = 500-1; //72000000/1000=72K  //1MHZ
      TIM_TimeBaseStructure.TIM_Prescaler = 0;
      TIM_TimeBaseStructure.TIM_ClockDivision = 0;
      TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
      TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);
      TIM_ARRPreloadConfig(TIM1,ENABLE);
      /* PWM1 Mode configuration: Channel1 */
      TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
      TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
      TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
      TIM_OCInitStructure.TIM_Pulse = CCR1_Val;
      TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
      TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;
      TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Reset;
      TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCNIdleState_Reset;
      TIM_OC1Init(TIM1, &TIM_OCInitStructure);
      TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);

      TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
      TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
      TIM_OCInitStructure.TIM_Pulse = CCR2_Val;
      TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
      TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;
      TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Reset;
      TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCNIdleState_Reset;
      TIM_OC2Init(TIM1, &TIM_OCInitStructure);
      TIM_OC2PreloadConfig(TIM1, TIM_OCPreload_Enable);
      TIM_BDTRInitStructure.TIM_OSSRState = TIM_OSSRState_Enable;
      TIM_BDTRInitStructure.TIM_OSSIState = TIM_OSSIState_Enable;

      TIM_BDTRInitStructure.TIM_LOCKLevel = TIM_LOCKLevel_OFF;
      TIM_BDTRInitStructure.TIM_DeadTime = 0x30;
      TIM_BDTRInitStructure.TIM_Break = TIM_Break_Disable;
      TIM_BDTRInitStructure.TIM_BreakPolarity = TIM_BreakPolarity_High;
      TIM_BDTRInitStructure.TIM_AutomaticOutput = TIM_AutomaticOutput_Enable;
      TIM_BDTRConfig(TIM1, &TIM_BDTRInitStructure);
      TIM_Cmd(TIM1, ENABLE);
      TIM_CtrlPWMOutputs(TIM1, ENABLE);
}
为什么PWM频率只能达到143K，初值装600就测试不到波形了，有什么方法可以达到1MHZ吗？