基于STM32的485通讯

jiaxinhui2011

基于STM32的485通讯 [复制链接]

void UART3Init(void)
{
        GPIO_InitTypeDef GPIO_InitStructure;
        USART_InitTypeDef USART_InitStructure;

        RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);
        RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC, ENABLE);//使能外设时钟  
         GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4 | GPIO_Pin_5 ;
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
        GPIO_Init(GPIOC, &GPIO_InitStructure);

 

        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
        GPIO_Init(GPIOB, &GPIO_InitStructure);

        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
        GPIO_Init(GPIOB, &GPIO_InitStructure);

        USART_InitStructure.USART_BaudRate = 9600;
        USART_InitStructure.USART_WordLength = USART_WordLength_8b;
        USART_InitStructure.USART_StopBits = USART_StopBits_1;
        USART_InitStructure.USART_Parity = USART_Parity_No;
        USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
        USART_InitStructure.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;
        USART_Init(USART3, &USART_InitStructure);

        USART_Cmd(USART3, ENABLE);
}

 

void UART3SendByte(unsigned char SendData)
{    Set_DE;
    Set_RE;DelayNmS(1);
        USART_SendData(USART3,SendData);
        while(USART_GetFlagStatus(USART3, USART_FLAG_TXE) == RESET);
  DelayNmS(1);
    Clr_DE;
    Clr_RE;
}

unsigned char UART3GetByte(unsigned char* GetData)
{
      Clr_DE;
    Clr_RE;DelayNmS(1);
        if(USART_GetFlagStatus(USART3, USART_FLAG_RXNE) == RESET)
        {
                return 0;//没有收到数据
        }

        *GetData = USART_ReceiveData(USART3);
    DelayNmS(1);
    Set_DE;
    Set_RE;

        return 1;//收到数据
}

void RS485_Test(void)
{
        unsigned char i = 0;
   unsigned char a = 0;

      while(1)
       {
          
      while(UART3GetByte(&i))
                { UART3SendByte(i);
           if(i==0x01){  LedOutput(0,1);}
     if(i==0x02){  LedOutput(1,1);}
     if(i==0x03){  LedOutput(2,1); }
     if(i==0x04){  LedOutput(0,0); LedOutput(1,0);  LedOutput(2,0);}

                }

   
                       
            
        }

     
}

astwyg

不错.回头加入资源贴~

jiaxinhui2011

谢谢啊