关于可变式PWM输出问题。

sankefeixing · 发表于 2016-4-29 15:36:49

      我要用STM32作svpwm，所以先写了一个小程序输出每个PWM波形都不一样的PWM波形。软件仿真结果如图：
      但是烧到片子里后用示波器现实的波形却是这样的，就像图片PWM1-PWM5一样的波形连续动态刷新。


      代码如下：
void TIM_Configuration(void)
{
TIM_TimeBaseInitTypeDef TTypeDef;
  TIM_OCInitTypeDef TIM_OCInitStructure;
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1,ENABLE);
  TIM_DeInit(TIM1);
  TTypeDef.TIM_Period=60000;
  TTypeDef.TIM_Prescaler=0;
  TTypeDef.TIM_ClockDivision=TIM_CKD_DIV1;
  TTypeDef.TIM_CounterMode=TIM_CounterMode_CenterAligned2;
  TIM_TimeBaseInit(TIM1 , &TTypeDef);
  TIM_ARRPreloadConfig(TIM1 , ENABLE);

TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
TIM_OCInitStructure.TIM_Pulse = 0;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;//TIM1_OCPolarity_High;
TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCPolarity_High;
TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Reset;//TIM1_OCIdleState_Set;
TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;
TIM_OC1Init(TIM1 , &TIM_OCInitStructure);
TIM_OC1PreloadConfig(TIM1 , TIM_OCPreload_Enable);
TIM_Cmd(TIM1 , ENABLE);
TIM_CtrlPWMOutputs(TIM1 , ENABLE);
  TIM1->DIER=0x0001;
}

void TIM1_UP_IRQHandler(void)
{
int x;
if (TIM_GetITStatus(TIM1, TIM_IT_Update)!= RESET)
{
   //TIM_ClearITPendingBit(TIM3, TIM_IT_CC1);
         TIM1->SR=0x0000;
   if (ClkCount==17)
         {
            ClkCount=0;
         }
         else
         {
            ClkCount++;
         }
         if (ClkCount%2!=0)
         {
         x=3000*ClkCount;
         TIM_SetCompare1(TIM1 , x);
         }
}
}