stm32串口中断+DMA出错

只看该作者 · 2010-10-19 16:32

我用stm32串口中断接收数据,DMA发送数据, 也就是接收上位发下来的一个命令,然后根据命令要求返回数据,我用下来总是发现单步执行是可以的,全速就出现数据丢失或者错位.其中DMA_channel4用的是正常模式,查询的方式.哪位达人帮忙提示下,问题可能出现在哪儿

只看该作者 · 2010-10-19 16:39

本帖最后由 lily_2010 于 2010-10-19 16:47 编辑

下面是我代码:我是接收20个数据,然后返回100个数据,在接收中断里打开DMA发送,在发送完成后打开接收中断
接收中断:
void USART1_IRQHandler(void)
{
if(USART_GetITStatus(USART1, USART_IT_RXNE) !=RESET)
  {
/* Read one byte from the receive data register */
   RxBuffer1[RxCounter++] = USART_ReceiveData(USART1);
   if(RxCounter == 20)
{
   // Disable the USART1 Receive interrupt
   USART_ITConfig(USART1, USART_IT_RXNE, DISABLE);
   RxCounter=0;
   TxBuffer1[0]=0x11;
   TxBuffer1[1]=0x22;
   TxBuffer1[2]=0x33;
   TxBuffer1[3]=0x44;
   TxBuffer1[4]=0x55;

   GPIO_SetBits(GPIOA, GPIO_Pin_12);       //使能发送  RTS=1
   DMA_Configuration();
   USART_DMACmd(USART1, USART_DMAReq_Tx, ENABLE); //打开DMA发送
   DMA_Cmd(DMA1_Channel4, ENABLE);
   /* Enable the USART1 */
   USART_Cmd(USART1, ENABLE);
}
if(USART_GetITStatus(USART1,USART_IT_ORE)==SET)
{
USART_ClearITPendingBit(USART1,USART_IT_ORE);
}
  }
}

主函数:
int main(void)
{
#ifdef DEBUG
  debug();
#endif
  u16 i,j;
  for(i=0;i<20;i++)
  {
RxBuffer1=0x00;
  }
  for(i=0;i<800;i++)
  {
TxBuffer1=0x00;
  }
  /* System Clocks Configuration */
  RCC_Configuration();
  /* NVIC configuration */
  NVIC_Configuration();
/* Configure the GPIO ports */
  GPIO_Configuration();
/* Configure the DMA */
  DMA_Configuration();
  GPIO_ResetBits(GPIOA, GPIO_Pin_12);       //receive  RTS=0

/* USART1 and USART2 configuration ------------------------------------------------------*/
  USART_DeInit(USART1);
  USART_InitStructure.USART_BaudRate = 115200;
  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_Rx | USART_Mode_Tx;

  /* Configure USART1 */
  USART_Init(USART1, &USART_InitStructure);
/* Enable USART1 DMA TX request */
// USART_DMACmd(USART1, USART_DMAReq_Tx, ENABLE);

/* Enable DMA1 Channel4 */
  //DMA_Cmd(DMA1_Channel4, ENABLE);

GPIO_ResetBits(GPIOA, GPIO_Pin_12);       //使能接收  RTS=0

  /* Enable the USART1 Receive Interrupt */
  USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);

/* Enable the USART1 */
USART_Cmd(USART1, ENABLE);
while (1)
  {
/* Wait until DMA1_Channel 4 Transfer Complete */
while (DMA_GetFlagStatus(DMA1_FLAG_TC4) == RESET)       //等待发送完成
{
}
DMA_ClearFlag(DMA1_FLAG_GL4);
//for(i=2000;i>0;i--);
GPIO_ResetBits(GPIOA, GPIO_Pin_12);             //使能接收  RTS=0
/* Enable the USART1 Receive Interrupt */
USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);    //使能接收中断
  }
}

void NVIC_Configuration(void)
{
#ifdef  VECT_TAB_RAM
  /* Set the Vector Table base location at 0x20000000 */
  NVIC_SetVectorTable(NVIC_VectTab_RAM, 0x0);
#else  /* VECT_TAB_FLASH  */
  /* Set the Vector Table base location at 0x08000000 */
  NVIC_SetVectorTable(NVIC_VectTab_FLASH, 0x0);
#endif
  NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);

  /* Enable the USART1 Interrupt */
  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);
}

/*******************************************************************************
* Function Name  : DMA_Configuration
* Description : Configures the DMA.
* Input       : None
* Output       : None
* Return       : None
*******************************************************************************/
void DMA_Configuration(void)
{
  DMA_InitTypeDef DMA_InitStructure;

  /* DMA1 Channel4 (triggered by USART1 Tx event) Config */
  DMA_DeInit(DMA1_Channel4);
  DMA_InitStructure.DMA_PeripheralBaseAddr = USART1_DR_Base;
  DMA_InitStructure.DMA_MemoryBaseAddr = (u32)TxBuffer1;
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
  DMA_InitStructure.DMA_BufferSize = TxBufferSize1;
  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_Mode = DMA_Mode_Circular;//add in 10.11
  //DMA_InitStructure.DMA_Priority = ;DMA_Priority_Medium
  DMA_InitStructure.DMA_Priority = DMA_Priority_VeryHigh;
  DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
  DMA_Init(DMA1_Channel4, &DMA_InitStructure);
}