STM32F4开发板----串口（002）

川长思鸟来 2022-05-20 05:04 188阅读 0赞

串口

# 1 相关串口库函数 #

/* Exported macro ------------------------------------------------------------*/
    /* Exported functions --------------------------------------------------------*/  
    
    /* Function used to set the USART configuration to the default reset state ***/
    void USART_DeInit(USART_TypeDef* USARTx);
    
    /* Initialization and Configuration functions *********************************/
    void USART_Init(USART_TypeDef* USARTx, USART_InitTypeDef* USART_InitStruct);
    void USART_StructInit(USART_InitTypeDef* USART_InitStruct);
    void USART_ClockInit(USART_TypeDef* USARTx, USART_ClockInitTypeDef* USART_ClockInitStruct);
    void USART_ClockStructInit(USART_ClockInitTypeDef* USART_ClockInitStruct);
    void USART_Cmd(USART_TypeDef* USARTx, FunctionalState NewState);
    void USART_SetPrescaler(USART_TypeDef* USARTx, uint8_t USART_Prescaler);
    void USART_OverSampling8Cmd(USART_TypeDef* USARTx, FunctionalState NewState);
    void USART_OneBitMethodCmd(USART_TypeDef* USARTx, FunctionalState NewState);
    
    /* Data transfers functions ***************************************************/
    void USART_SendData(USART_TypeDef* USARTx, uint16_t Data);
    uint16_t USART_ReceiveData(USART_TypeDef* USARTx);
    
    /* Multi-Processor Communication functions ************************************/
    void USART_SetAddress(USART_TypeDef* USARTx, uint8_t USART_Address);
    void USART_WakeUpConfig(USART_TypeDef* USARTx, uint16_t USART_WakeUp);
    void USART_ReceiverWakeUpCmd(USART_TypeDef* USARTx, FunctionalState NewState);
    
    /* LIN mode functions *********************************************************/
    void USART_LINBreakDetectLengthConfig(USART_TypeDef* USARTx, uint16_t USART_LINBreakDetectLength);
    void USART_LINCmd(USART_TypeDef* USARTx, FunctionalState NewState);
    void USART_SendBreak(USART_TypeDef* USARTx);
    
    /* Half-duplex mode function **************************************************/
    void USART_HalfDuplexCmd(USART_TypeDef* USARTx, FunctionalState NewState);
    
    /* Smartcard mode functions ***************************************************/
    void USART_SmartCardCmd(USART_TypeDef* USARTx, FunctionalState NewState);
    void USART_SmartCardNACKCmd(USART_TypeDef* USARTx, FunctionalState NewState);
    void USART_SetGuardTime(USART_TypeDef* USARTx, uint8_t USART_GuardTime);
    
    /* IrDA mode functions ********************************************************/
    void USART_IrDAConfig(USART_TypeDef* USARTx, uint16_t USART_IrDAMode);
    void USART_IrDACmd(USART_TypeDef* USARTx, FunctionalState NewState);
    
    /* DMA transfers management functions *****************************************/
    void USART_DMACmd(USART_TypeDef* USARTx, uint16_t USART_DMAReq, FunctionalState NewState);
    
    /* Interrupts and flags management functions **********************************/
    void USART_ITConfig(USART_TypeDef* USARTx, uint16_t USART_IT, FunctionalState NewState);
    FlagStatus USART_GetFlagStatus(USART_TypeDef* USARTx, uint16_t USART_FLAG);
    void USART_ClearFlag(USART_TypeDef* USARTx, uint16_t USART_FLAG);
    ITStatus USART_GetITStatus(USART_TypeDef* USARTx, uint16_t USART_IT);
    void USART_ClearITPendingBit(USART_TypeDef* USARTx, uint16_t USART_IT);

# 2 配置步骤 #

1.  使能串口时钟，GPIO时钟使能
2.  串口复位
3.  设置串口端口模式
4.  串口参数初始化 使能串口
5.  中断处理

void USART1_IRQHandler(void)                    //串口1中断服务程序
    {
        u8 Res;
    #if SYSTEM_SUPPORT_OS //如果SYSTEM_SUPPORT_OS为真，则需要支持OS
        OSIntEnter();    
    #endif
        if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET)  //接收中断（接收到的数据必须是0x0d 0x0a结尾）
        {
            Res =USART_ReceiveData(USART1);//(USART1->DR); //读取接收到的数据
    
            if((USART_RX_STA&0x8000)==0)//接收未完成
            {
                if(USART_RX_STA&0x4000)//接收到ll了0x0d
                {
                    if(Res!=0x0a)USART_RX_STA=0;//接收错误，重新开始
                    else USART_RX_STA|=0x8000;    //接收完成了
                }
                else //还没有接收到0x0D
                {    
                    if(Res==0x0d)USART_RX_STA|=0x4000;
                    else
                    {
                        USART_RX_BUF[USART_RX_STA&0X3FFF]=Res ;
                        USART_RX_STA++;
                        if(USART_RX_STA>(USART_REC_LEN-1))USART_RX_STA=0;//接收数据错误，重新开始接收
                    }        
                }
            }           
      }

主函数处理部分

while(1)
        {
            if(USART_RX_STA&0x8000)
            {                       
                len=USART_RX_STA&0x3fff;
                printf("\r\nÄ666:\r\n");
                for(t=0;t<len;t++)
                {
                    USART_SendData(USART1, USART_RX_BUF[t]);  //向串口1发送数据
                    while(USART_GetFlagStatus(USART1,USART_FLAG_TC)!=SET);//等待发送结束
                }
                printf("\r\n\r\n");//插入换行
                USART_RX_STA=0;
            }else
            {
                times++;
                if(times%5000==0)
                {
                    printf("\r\n串口实验：\r\n");
                    printf("666\r\n\r\n\r\n");
                }
                if(times%200==0)printf("输入数据，以回车结束\r\n");  
                if(times%30==0)LED0=!LED0;//LED闪烁，提示系统正在运行
                delay_ms(10);   
            }
        }