【原創】TIM5_CH2高速脈沖DMA捕獲（STM32F407ZE）

/**
  * @brief  TIM5_DMA_Capture_Config
  * @param  None
  * @retval None
  */
void TIM5_DMA_Capture_Config(void)
{
GPIO_InitTypeDef GPIO_InitStruct;
  DMA_InitTypeDef DMA_InitStructure;
  NVIC_InitTypeDef NVIC_InitStructure;
  TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
  TIM_ICInitTypeDef TIM_ICInitStructure;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
  /** TIM5 GPIO Configuration
     PA1  ------> TIM5_CH2
  */
  GPIO_InitStruct.GPIO_Pin = GPIO_Pin_1; /* PA1: TIM5_CH2 捕獲腳 */
  GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStruct.GPIO_OType = GPIO_OType_OD;
  GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_DOWN;
  GPIO_InitStruct.GPIO_Speed = GPIO_Speed_25MHz;
  GPIO_Init(GPIOA, &GPIO_InitStruct);
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource1, GPIO_AF_TIM5);
  DMA_DeInit(DMA1_Stream4);
  /* Enable DMA1 clocks ****************************************/
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5, ENABLE);
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1, ENABLE);
  //TIM5_CH2 的捕獲模式CCR2
  /* DMA1_Stream4 channel6 configuration **************************************/
  DMA_InitStructure.DMA_Channel = DMA_Channel_6;
  DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)(&TIM5->CCR2);
  DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)TIM5_CCR2_Buff;
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory; /* 0：從外設讀  */
  DMA_InitStructure.DMA_BufferSize = 20;
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word;
  DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;
  DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;
  DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;         
  DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
  DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
  DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
  DMA_Init(DMA1_Stream4, &DMA_InitStructure);   
  DMA_ITConfig(DMA1_Stream4, DMA_IT_TC, ENABLE);
  DMA_Cmd(DMA1_Stream4, ENABLE);

  /* Enable the TIM5 gloabal Interrupt */
  NVIC_InitStructure.NVIC_IRQChannel = TIM5_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelCmd = DISABLE;
  NVIC_Init(&NVIC_InitStructure);
  
  NVIC_InitStructure.NVIC_IRQChannel = DMA1_Stream4_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

  TIM_DeInit(TIM5);
  /* TIM5 clock enable */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5, ENABLE);
  
  /* Time base configuration */
  TIM_TimeBaseStructure.TIM_Period = 0xFFFFFFFF;  // TIMx_ARR 32位 1000000us
  TIM_TimeBaseStructure.TIM_Prescaler = 0;        // TIMx_PSC 16位 APB1 Timer clk 84MHz
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseInit(TIM5, &TIM_TimeBaseStructure);
  /* TIMx configuration: Input Capture mode ---------------------
  The external signal is connected to TIMx CH1 pin
  ------------------------------------------------------------ */
  TIM_ICInitStructure.TIM_Channel = TIM_Channel_2;
  TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
  TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
  TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
  TIM_ICInitStructure.TIM_ICFilter = 0x0;
  TIM_ICInit(TIM5, &TIM_ICInitStructure);  
  TIM_SelectInputTrigger(TIM5, TIM_TS_TI2FP2);
  TIM_SelectSlaveMode(TIM5, TIM_SlaveMode_Reset);
  TIM_SelectCCDMA(TIM5,ENABLE);
  TIM_DMAConfig(TIM5, TIM_DMABase_CCR2, TIM_DMABurstLength_16Bytes);
  TIM_DMACmd(TIM5, TIM_DMA_CC2, ENABLE);
  TIM_SetCounter(TIM5, 0);
  /* TIM5 Enable Counter */
  TIM_Cmd(TIM5, ENABLE);
}