stm32 USART串口通信

 

UART初始化函数:

HAL_StatusTypeDef HAL_UART_Init(UART_HandleTypeDef *huart)

参数结构体:

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;

第二个成员的结构体:

typedef struct
{
  uint32_t BaudRate;                  /*!< This member configures the UART communication baud rate.
                                           The baud rate register is computed using the following formula:
                                           - If oversampling is 16 or in LIN mode,
                                              Baud Rate Register = ((PCLKx) / ((huart->Init.BaudRate)))
                                           - If oversampling is 8,
                                              Baud Rate Register[15:4] = ((2 * PCLKx) / ((huart->Init.BaudRate)))[15:4]
                                              Baud Rate Register[3] =  0
                                              Baud Rate Register[2:0] =  (((2 * PCLKx) / ((huart->Init.BaudRate)))[3:0]) >> 1      */

  uint32_t WordLength;                /*!< Specifies the number of data bits transmitted or received in a frame.
                                           This parameter can be a value of @ref UARTEx_Word_Length */

  uint32_t StopBits;                  /*!< Specifies the number of stop bits transmitted.
                                           This parameter can be a value of @ref UART_Stop_Bits */

  uint32_t Parity;                    /*!< Specifies the parity mode.
                                           This parameter can be a value of @ref UART_Parity
                                           @note When parity is enabled, the computed parity is inserted
                                                 at the MSB position of the transmitted data (9th bit when
                                                 the word length is set to 9 data bits; 8th bit when the
                                                 word length is set to 8 data bits). */

  uint32_t Mode;                      /*!< Specifies whether the Receive or Transmit mode is enabled or disabled.
                                           This parameter can be a value of @ref UART_Mode */

  uint32_t HwFlowCtl;                 /*!< Specifies whether the hardware flow control mode is enabled
                                           or disabled.
                                           This parameter can be a value of @ref UART_Hardware_Flow_Control */

  uint32_t OverSampling;              /*!< Specifies whether the Over sampling 8 is enabled or disabled, to achieve higher speed (up to fPCLK/8).
                                           This parameter can be a value of @ref UART_Over_Sampling */

  uint32_t OneBitSampling;            /*!< Specifies whether a single sample or three samples' majority vote is selected.
                                           Selecting the single sample method increases the receiver tolerance to clock
                                           deviations. This parameter can be a value of @ref UART_OneBit_Sampling */
}UART_InitTypeDef;

示例:

u8 aRxBuffer[RXBUFFERSIZE];//HAL库使用的串口接收缓冲
UART_HandleTypeDef UART1_Handler; //UART句柄

//初始化IO 串口1 
//bound:波特率
void uart_init(u32 bound)
{    
    //UART 初始化设置
    UART1_Handler.Instance=USART1;                        //USART1
    UART1_Handler.Init.BaudRate=bound;                    //波特率
    UART1_Handler.Init.WordLength=UART_WORDLENGTH_8B;   //字长为8位数据格式
    UART1_Handler.Init.StopBits=UART_STOPBITS_1;        //一个停止位
    UART1_Handler.Init.Parity=UART_PARITY_NONE;            //无奇偶校验位
    UART1_Handler.Init.HwFlowCtl=UART_HWCONTROL_NONE;   //无硬件流控
    UART1_Handler.Init.Mode=UART_MODE_TX_RX;            //收发模式
    HAL_UART_Init(&UART1_Handler);                        //HAL_UART_Init()会使能UART1
    
    HAL_UART_Receive_IT(&UART1_Handler, (u8 *)aRxBuffer, RXBUFFERSIZE);//该函数会开启接收中断:标志位UART_IT_RXNE,并且设置接收缓冲以及接收缓冲接收最大数据量
  
}

发送数据:

HAL_StatusTypeDef HAL_UART_Transmit(UART_HandleTypeDef *huart, uint8_t *pData, uint16_t Size, uint32_t Timeout)

第一个参数:句柄 (和HAL_UART_Init的参数相同)

第二个参数:发送数据的数组指针

第三个参数:数组长度

第四个参数:超时时间

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转载自www.cnblogs.com/qifeng1024/p/12057786.html