为什么我的采样频率达不到0.1HZ？

只看该作者 · 2021-8-3 12:00

/******************************************************************************/
/*          AT32F4xx Peripherals Interrupt Handlers                      */
/******************************************************************************/
/**
  * @brief  This function handles TMR3 global interrupt request.
  * @param  None
  * @retval None
  */
void TMR3_GLOBAL_IRQHandler(void)
{
  if(TMR_GetINTStatus(TMR3, TMR_INT_CC2) == SET)
  {
/* Clear TMR3 Capture compare interrupt pending bit */
TMR_ClearITPendingBit(TMR3, TMR_INT_CC2);
if(CaptureNumber == 0)
{
   /* Get the Input Capture value */
   IC3ReadValue1 = TMR_GetCapture2(TMR3);
   CaptureNumber = 1;
}
else if(CaptureNumber == 1)
{
   /* Get the Input Capture value */
   IC3ReadValue2 = TMR_GetCapture2(TMR3);

   /* Capture computation */
   if (IC3ReadValue2 > IC3ReadValue1)
   {
      Capture = (IC3ReadValue2 - IC3ReadValue1);
   }
   else
   {
      Capture = ((0xFFFF - IC3ReadValue1) + IC3ReadValue2);
   }
   /* Frequency computation */
   TMR3Freq =  SystemCoreClock /24000.0/ Capture;
   CaptureNumber = 0;
}
  }
}
void rpm_init(void)
{
  /* System Clocks Configuration */
  RCC_Configuration();

  /* NVIC configuration */
  NVIC_Configuration();


  /* Configure the GPIO ports */
  GPIO_Configuration();

TMR_TimerBaseInitType TMR_TMReBaseStructure;

/* TMRe base configuration */
  TMR_TimeBaseStructInit(&TMR_TMReBaseStructure);
  TMR_TMReBaseStructure.TMR_Period = 65535;
  TMR_TMReBaseStructure.TMR_DIV = 24000-1;
  TMR_TMReBaseStructure.TMR_ClockDivision = 0;
  TMR_TMReBaseStructure.TMR_CounterMode = TMR_CounterDIR_Up;

  TMR_TimeBaseInit(TMR3, &TMR_TMReBaseStructure);

  /* TMR3 configuration: Input Capture mode ---------------------
   The external signal is connected to TMR3 CH2 pin (PA.07)
   The Rising edge is used as active edge,
   The TMR3 CCR2 is used to compute the frequency value
  ------------------------------------------------------------ */

  TMR_ICStructInit(&TMR_ICInitStructure);
  TMR_ICInitStructure.TMR_Channel = TMR_Channel_2;
  TMR_ICInitStructure.TMR_ICPolarity = TMR_ICPolarity_Rising;
  TMR_ICInitStructure.TMR_ICSelection = TMR_ICSelection_DirectTI;
  TMR_ICInitStructure.TMR_ICDIV = TMR_ICDIV_DIV1;
  TMR_ICInitStructure.TMR_ICFilter = 0x0;

  TMR_ICInit(TMR3, &TMR_ICInitStructure);

  /* TMR enable counter */
  TMR_Cmd(TMR3, ENABLE);

  /* Enable the CC2 Interrupt Request */
  TMR_INTConfig(TMR3, TMR_INT_CC2, ENABLE);

}

只看该作者 · 2021-8-4 07:52

你确定采样率没问题？