八度空间 发表于 2018-4-22 13:15
初始化代码贴一下看看

GPIO_InitTypeDef GPIO_InitStructure;
        USART_InitTypeDef USART_InitStructure;
        NVIC_InitTypeDef NVIC_InitStructure;
       
        RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC,ENABLE); //使能GPIOA时钟
        RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART6,ENABLE);//使能USART2时钟

  //串口2引脚复用映射
        GPIO_PinAFConfig(GPIOC,GPIO_PinSource6,GPIO_AF_USART6); //GPIOA2复用为USART2
        GPIO_PinAFConfig(GPIOC,GPIO_PinSource7,GPIO_AF_USART6); //GPIOA2复用为USART2
        //USART2   
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7; //GPIOA2与GPIOA3
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;//复用功能
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;        //速度100MHz
        GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; //推挽复用输出
        GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; //上拉
        GPIO_Init(GPIOC,&GPIO_InitStructure); //初始化PA2，PA3
        //PG8推挽输出，485模式控制  

   //USART2 初始化设置
        USART_InitStructure.USART_BaudRate = 9600;//波特率设置
        USART_InitStructure.USART_WordLength = USART_WordLength_8b;//字长为8位数据格式
        USART_InitStructure.USART_StopBits = USART_StopBits_1;//一个停止位
        USART_InitStructure.USART_Parity = USART_Parity_No;//无奇偶校验位
        USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//无硬件数据流控制
        USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;        //收发模式
  USART_Init(USART6, &USART_InitStructure); //初始化串口2
       
  USART_Cmd(USART6, ENABLE);  //使能串口 2
       
        USART_ClearFlag(USART6, USART_FLAG_TC);
       

        USART_ITConfig(USART6, USART_IT_RXNE, ENABLE);//开启接受中断

        //Usart2 NVIC 配置
  NVIC_InitStructure.NVIC_IRQChannel = USART6_IRQn;
        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3;//抢占优先级3
        NVIC_InitStructure.NVIC_IRQChannelSubPriority =3;                //子优先级3
        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;                        //IRQ通道使能
        NVIC_Init(&NVIC_InitStructure);        //根据指定的参数初始化VIC寄存器、



BOOL
xMBPortSerialPutByte( CHAR ucByte )
{
    /* Put a byte in the UARTs transmit buffer. This function is called
     * by the protocol stack if pxMBFrameCBTransmitterEmpty( ) has been
     * called. */
   
        USART_SendData(USART6, ucByte);  //发送一个字节
       
        return TRUE;
}

BOOL
xMBPortSerialGetByte( CHAR * pucByte )
{
    /* Return the byte in the UARTs receive buffer. This function is called
     * by the protocol stack after pxMBFrameCBByteReceived( ) has been called.
     */
   
        *pucByte = USART_ReceiveData(USART6);  //接收一个字节
       
        return TRUE;
}

/* Create an interrupt handler for the transmit buffer empty interrupt
* (or an equivalent) for your target processor. This function should then
* call pxMBFrameCBTransmitterEmpty( ) which tells the protocol stack that
* a new character can be sent. The protocol stack will then call
* xMBPortSerialPutByte( ) to send the character.
*/
void prvvUARTTxReadyISR( void )
{
    pxMBFrameCBTransmitterEmpty(  );
}

/* Create an interrupt handler for the receive interrupt for your target
* processor. This function should then call pxMBFrameCBByteReceived( ). The
* protocol stack will then call xMBPortSerialGetByte( ) to retrieve the
* character.
*/
void prvvUARTRxISR( void )
{
    pxMBFrameCBByteReceived(  );
}

/**
  *****************************************************************************
  * @name   : 串口2中断服务函数
  *
  * @Brief  : none
  *
  * @Input  : none
  *
  * @Output : none
  *
  * @Return : none
  *****************************************************************************
**/
u8 MB_RX_BUF[64];          //接收缓冲,最大64个字节.
//接收到的数据长度
u8 MB_RX_CNT=0;   
void USART6_IRQHandler(void)
{
        if (USART_GetITStatus(USART6, USART_IT_RXNE) == SET) //接收中断
        {
                prvvUARTRxISR();
                USART_ClearITPendingBit(USART6, USART_IT_RXNE);
        }
       
        if (USART_GetITStatus(USART6, USART_IT_TC) == SET)  //发送中断
        {
                prvvUARTTxReadyISR();
                USART_ClearITPendingBit(USART6, USART_IT_TC);
        }
}