关于HAL库串口结构体疑问

lyf · 发表于 2017-1-21 10:31:10

  */
typedef struct
{
  USART_TypeDef          *Instance;       /*!< UART registers base address       */

  UART_InitTypeDef       Init;          /*!< UART communication parameters    */

  UART_AdvFeatureInitTypeDef AdvancedInit; /*!< UART Advanced Features initialization parameters */

  uint8_t                *pTxBuffPtr;    /*!< Pointer to UART Tx transfer Buffer */

  uint16_t                TxXferSize;    /*!< UART Tx Transfer size             */

  uint16_t                TxXferCount;    /*!< UART Tx Transfer Counter          */

  uint8_t                *pRxBuffPtr;    /*!< Pointer to UART Rx transfer Buffer */

  uint16_t                RxXferSize;    /*!< UART Rx Transfer size             */

  uint16_t                RxXferCount;    /*!< UART Rx Transfer Counter          */

  uint16_t                Mask;          /*!< UART Rx RDR register mask       */

  DMA_HandleTypeDef       *hdmatx;       /*!< UART Tx DMA Handle parameters    */

  DMA_HandleTypeDef       *hdmarx;       /*!< UART Rx DMA Handle parameters    */

  HAL_LockTypeDef       Lock;          /*!< Locking object                   */

  __IO HAL_UART_StateTypeDef gState;    /*!< UART state information related to global Handle management
                                                and also related to Tx operations.
                                                This parameter can be a value of @ref HAL_UART_StateTypeDef */

  __IO HAL_UART_StateTypeDef RxState;    /*!< UART state information related to Rx operations.
                                                This parameter can be a value of @ref HAL_UART_StateTypeDef */

  __IO uint32_t          ErrorCode;    /*!< UART Error code                   */

}UART_HandleTypeDef;

请问UART_HandleTypeDef结构体中RxXferSize和RxXferCount有什么区别呢？在HAL_UART_Receive_IT函数里把两个值都赋一样的值？？
huart->pRxBuffPtr = pData;
huart->RxXferSize = Size;
huart->RxXferCount = Size;