STM32

STM32485串口只能发送第一个字符问题

2019-08-18 19:56发布

站内问答 / STM32/STM8
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本帖最后由 769417953 于 2017-5-19 09:49 编辑

STM32调试时发现当波特率为9600时串口助手收到程序发送出来的字符只有第一个字符，但是当把USART的波特率设置成38400时，串口助手就能收到完整的命令，哪位大神能解释下原因吗？？[mw_shl_code=c,true]void USART1_IRQHandler(void)
{
  u8 ucUartTemp;
  if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET)
  {
    ucUartTemp = USART_ReceiveData(USART1);
    Usart1.TimeOutCounter = Reset;
    if(Usart1.Usart_RxStatus == RX_IDLE)
    {
      if(ucUartTemp == Usart_StartMark )
      {
        
        Usart1.Usart_RxStatus = RX_HEAD;
        Usart1.Usart_ReceiveCache[CPOS_Start] = ucUartTemp;
        Usart1.Usart_Cache_Where = CPOS_CMD;
      }
    }
    else if(Usart1.Usart_RxStatus == RX_HEAD )
    {
      if(Usart1.Usart_Cache_Where == CPOS_Length-1)
        Usart1.Usart_RxStatus = RX_Length;
      Usart1.Usart_ReceiveCache[Usart1.Usart_Cache_Where] = ucUartTemp;
      Usart1.Usart_Cache_Where ++;
    }
    else if(Usart1.Usart_RxStatus == RX_Length)
    {
      Usart1.Usart_ReceiveCache[Usart1.Usart_Cache_Where] = ucUartTemp;
      Usart1.Usart_Cache_Where++;
//      if((Usart1.Usart_Cache_Where > Usart1_ReceiveLength) ||
//         (Usart1.Usart_Cache_Where > (Usart1.Usart_ReceiveCache[CPOS_Length] -'0')*10 + (Usart1.Usart_ReceiveCache[CPOS_Length+1] -'0')*1))
//      {//接收超过限定长度
//        Usart1.Err_Code = ERR_OutLength;
//        Usart1.Usart_RxStatus = RX_END;
//      }
      if((Usart1.Usart_ReceiveCache[CPOS_Start] == Usart_StartMark ) &&
         Usart1.Usart_Cache_Where == Usart1.Usart_ReceiveCache[CPOS_Length] )
      {//正确接收完成
        Usart1.Usart_RxStatus = RX_END;
      }
    }
  }
    ucUartTemp=USART1->SR;
    //if(ucUartTemp==RESET)ucUartTemp=Reset;
    ucUartTemp=USART1->DR;
    //if(ucUartTemp==RESET)ucUartTemp=Reset;
}

void Usart1Comm_app(void)
{


  if(Usart1.Usart_RxStatus == RX_END)
  {
    u8 i=0;
    //u8* crc;
    //CRC
   
    //for(i=0;i<Usart1.Usart_Cache_Where-4;i++)
     // temp8 ^= Usart1.Usart_ReceiveCache;
//    if(temp8 != (u8)AsciiHEXtoInt(Usart1.Usart_ReceiveCache+Usart1.Usart_Cache_Where-2,2))
//    {
//      if(Usart1.Err_Code == Reset)
//        Usart1.Err_Code = ERR_CRC;//CRC校验错误
//    }
//    else
    //CRC正确
      for(i=0;i<Usart1_ReportLength;i++)
        Usart1.Usart_ReportCache = 0;
      for(i=0;i<CPOS_CMD+1;i++)
        Usart1.Usart_ReportCache = Usart1.Usart_ReceiveCache;
      DeviceCode = (u8)AsciiHEXtoInt(Usart1.Usart_ReceiveCache+CPOS_Device,2);
      switch (Usart1.Usart_ReceiveCache[CPOS_CMD])
      {
      case CMD_GetVER:
        {     
        /////////////////////////////////////Report////////////////////////////////////////////
        //memcpy(Usart1.Usart_ReportCache+7,Usart1.Usart_ReceiveCache+7,Usart1.Usart_Cache_Where);
        //步骤代码
        Usart1.Usart_ReportCache[2] = 0x07;
        Usart1.Usart_ReportCache[3] = 0x40;
        Usart1.Usart_ReportCache[4] = 0x96;
        Usart1.Usart_RxStatus = RX_IDLE;
        Usart1.Err_Code = Reset;
        break;}
    default:
        Usart1.Err_Code = ERR_NoDefCMD;//未定义命令
        break;
      }
      
      Uart_PutChar(1,Usart1.Usart_ReportCache,7);
      DelayNms(1);
       RS485_DE_L();
}
}[/mw_shl_code]下面是串口初始化程序[mw_shl_code=applescript,true]void Five_usart_init(void)
{
  /* Timer Clock configuration ------------------------------------------------*/
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1 ,ENABLE);
//  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA2 ,ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);
// RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2,ENABLE);
// RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3,ENABLE);
// RCC_APB1PeriphClockCmd(RCC_APB1Periph_UART4,ENABLE);
//  RCC_APB1PeriphClockCmd(RCC_APB1Periph_UART5,ENABLE);
  

  
  /* Timer Interrupt configuration ---------------------------------------------*/
  NVIC_InitTypeDef NVIC_InitStructure;
  NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//4组抢占 4组从优先
  NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQChannel;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
  NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQChannel;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
  NVIC_Init(&NVIC_InitStructure);
  NVIC_InitStructure.NVIC_IRQChannel = USART3_IRQChannel;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
  NVIC_Init(&NVIC_InitStructure);
  NVIC_InitStructure.NVIC_IRQChannel = UART4_IRQChannel;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;
  NVIC_Init(&NVIC_InitStructure);
//  NVIC_InitStructure.NVIC_IRQChannel = USART5_IRQChannel;
//  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
//  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
//  NVIC_Init(&NVIC_InitStructure);
  
  /* Usart configuration ---------------------------------------------*/
  Usart_init(USART1,Usart1_BandRate,USART_WordLength_8b,USART_StopBits_1,USART_Parity_No,USART_HardwareFlowControl_None);
  USART_ITConfig(USART1,USART_IT_RXNE,ENABLE);
  USART_Cmd(USART1, ENABLE);
  //使能u1-tx DMA发送
  Usart_DMAtx_init(USART1,DMA1_Channel4);
  DMA_Cmd(DMA1_Channel4, ENABLE);
  USART_DMACmd(USART1, USART_DMAReq_Tx, ENABLE);

  Usart_init(USART2,Usart2_BandRate,USART_WordLength_8b,USART_StopBits_1,USART_Parity_No,USART_HardwareFlowControl_None);
  USART_ITConfig(USART2,USART_IT_RXNE,ENABLE);
  //USART_Cmd(USART2, ENABLE);  //使能串口2
  
  Usart_init(USART3,Usart3_BandRate,USART_WordLength_8b,USART_StopBits_1,USART_Parity_No,USART_HardwareFlowControl_None);
  USART_ITConfig(USART3,USART_IT_RXNE,ENABLE);
// USART_Cmd(USART3, ENABLE);  //使能串口3
  
  Usart_init(UART4,Usart4_BandRate,USART_WordLength_8b,USART_StopBits_1,USART_Parity_No,USART_HardwareFlowControl_None);
  USART_ITConfig(UART4,USART_IT_RXNE,ENABLE);
  //USART_Cmd(UART4, ENABLE);  //使能串口4
  
  Usart_init(UART5,Usart5_BandRate,USART_WordLength_8b,USART_StopBits_1,USART_Parity_No,USART_HardwareFlowControl_None);
  USART_ITConfig(UART5,USART_IT_RXNE,ENABLE);
  //USART_Cmd(UART5, ENABLE);  //使能串口5
  DelayNms(50);
  /* Timer GPIO configuration ------------------------------------------------*/
  Set_Port_Status(GPIO_A,GPIO_Pin_9,GPIO_Mode_AF_PP);          //TX1
  Set_Port_Status(GPIO_A,GPIO_Pin_10,GPIO_Mode_IN_FLOATING);   //RX1
  Set_Port_Status(GPIO_A,GPIO_Pin_2,GPIO_Mode_AF_PP);        //TX2
  Set_Port_Status(GPIO_A,GPIO_Pin_3,GPIO_Mode_IN_FLOATING);  //RX2
  Set_Port_Status(GPIO_B,GPIO_Pin_10,GPIO_Mode_AF_PP);       //TX3
  Set_Port_Status(GPIO_B,GPIO_Pin_11,GPIO_Mode_IN_FLOATING); //RX3
  Set_Port_Status(GPIO_C,GPIO_Pin_10,GPIO_Mode_AF_PP);       //TX4
  Set_Port_Status(GPIO_C,GPIO_Pin_11,GPIO_Mode_IN_FLOATING); //RX4
  //Set_Port_Status(GPIO_C,GPIO_Pin_12,GPIO_Mode_AF_PP);       //TX5
  //Set_Port_Status(GPIO_C,GPIO_Pin_13,GPIO_Mode_IN_FLOATING); //RX5
}
/*******************************************************************************
*函数名称：
*******************************************************************************/
void Usart_init(USART_TypeDef* USARTx,u32 Usartx_BandRate,u16 USARTx_WordLength,u16 USARTx_StopBits,u16 USARTx_Parity,u16 USARTx_HardwareFlowControl)
{
  USART_InitTypeDef USART_InitStructure;                          
  USART_InitStructure.USART_BaudRate = Usartx_BandRate;           
  USART_InitStructure.USART_WordLength = USARTx_WordLength;     
  USART_InitStructure.USART_StopBits = USARTx_StopBits;         
  USART_InitStructure.USART_Parity = USARTx_Parity;            
  USART_InitStructure.USART_HardwareFlowControl = USARTx_HardwareFlowControl;
  USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
  USART_Init(USARTx, &USART_InitStructure);
}
/*******************************************************************************
*函数名称：
*******************************************************************************/
void Usart_DMAtx_init(USART_TypeDef* USARTx,DMA_Channel_TypeDef * DMAx_Channelx)
{
  DMA_InitTypeDef DMA_InitStructure;
  DMA_InitStructure.DMA_PeripheralBaseAddr = (u32)(&USARTx->DR);
  DMA_InitStructure.DMA_MemoryBaseAddr = (u32)(&USARTx->DR);
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
  DMA_InitStructure.DMA_BufferSize = 1;
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
  DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;
  DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;
  DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
  DMA_Init(DMAx_Channelx, &DMA_InitStructure);
}[/mw_shl_code]

以及串口发送命令程序

[mw_shl_code=applescript,true]void  Uart_PutChar(u8 CH,u8 *p,u8 NUM)
{
  u16 i=0;
  u8 j=0;
  switch(CH)
  {
  case 1:
   //USART_ITConfig(USART1,USART_IT_RXNE,DISABLE);
    //USART_ClearITPendingBit(USART1,USART_IT_RXNE);
    //USART_ClearITPendingBit(USART1,USART_IT_IDLE);
    //USART_ClearITPendingBit(USART1,USART_IT_ORE);
    //USART_ClearFlag(USART1,USART_FLAG_RXNE);
    //USART_ClearFlag(USART1,USART_FLAG_IDLE);  
    //USART_ClearFlag(USART1,USART_FLAG_ORE);
    //GPIOA->CRH |= 0x00000300; //RX端口设置 设为输出模式 防止进入usart-ORE中断
    //DMA_Send585_END=0;
    //DMA_Send585_END_Timer=0;//用于延迟485使能端
    //GPIO_SetBits(GPIOA, GPIO_Pin_10);
    RS485_DE_H();
    DelayNms(5);
    DMA_Cmd(DMA1_Channel4, DISABLE);
    DMA1_Channel4->CNDTR=NUM;
    DMA1_Channel4->CMAR=(u32)p;
    DMA_Cmd(DMA1_Channel4, ENABLE);

    break;
  case 2:
    for(i=0;i<NUM;i++)
    {
      j = *(p+i);
      USART2->DR = (j & (u16)0x01FF);
      while(!(USART2->SR & USART_FLAG_TXE));
    }
    break;
  case 3:
    for(i=0;i<NUM;i++)
    {
      j = *(p+i);
      USART3->DR = (j & (u16)0x01FF);
      while(!(USART3->SR & USART_FLAG_TXE));
    }
    break;
  case 4:
    for(i=0;i<NUM;i++)
    {
      j = *(p+i);
      UART4->DR = (j & (u16)0x01FF);
      while(!(UART4->SR & USART_FLAG_TXE));
    }
    break;
  case 5:
    for(i=0;i<NUM;i++)
    {
      j = *(p+i);
      UART5->DR = (j & (u16)0x01FF);
      while(!(UART5->SR & USART_FLAG_TXE));
    }
    break;
  }
}[/mw_shl_code]
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正点原子
1楼-- · 2019-08-18 21:28
 精彩回答 2  元偷偷看……

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