DMA_USART1通信收发不正常

stm32_f2 提问时间：2016-3-17 10:22 /

#include "stm32f2xx.h"
#include <stdio.h>
#define USART1_DR_ADDRESS             ((uint32_t)USART1 + 0x04)
#define DMA_Rec_Len 32

void RCC_Configuration(void);
void NVIC_Configuration(void);
void GPIO_Configuration(void);
void USART_Configuration(void);
void DMA_Configuration(void);
void USART1_SendString(uint8_t *ch);
void UART1_SendByte(uint16_t Data);
void USART1_Send(u8 *buf,u8 len);

uint8_t DMA_Rece_Buf[DMA_Rec_Len];
int16_t USART1_Rec_Cnt=0;

int main(void)
{
  //int16_t j;
      uint8_t i;

  RCC_Configuration();
  GPIO_Configuration();
  USART_Configuration();

      DMA_Configuration();

      NVIC_Configuration();

  while (1)
  {

}

void DMA_Configuration(void)
{
  DMA_InitTypeDef  DMA_InitStructure;
      DMA_DeInit(DMA2_Stream5);
      DMA_InitStructure.DMA_Channel = DMA_Channel_4;
      DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
      DMA_InitStructure.DMA_PeripheralBaseAddr = USART1_DR_ADDRESS;
      DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)DMA_Rece_Buf;
      DMA_InitStructure.DMA_BufferSize = DMA_Rec_Len;
      DMA_Init(DMA2_Stream5, &DMA_InitStructure);

  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
  DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
  DMA_InitStructure.DMA_Priority = DMA_Priority_VeryHigh;
  DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;

DMA_Init(DMA2_Stream5, &DMA_InitStructure);

USART_DMACmd(USART1, USART_DMAReq_Rx, ENABLE);

DMA_Cmd(DMA2_Stream5, ENABLE);
}

//USART1
void USART1_IRQHandler(void)
{

  u16 i;
      flag=1;
  if(USART_GetITStatus(USART1, USART_IT_IDLE) != RESET)////½óêÕÖD¶Ï
  {
            DMA_Cmd(DMA2_Stream5, DISABLE);//1Ø±ÕUSART1 TX DMA1 ËùÖ¸ê¾μÄí¨μà
            if(USART_GetFlagStatus(USART2,USART_FLAG_ORE)==SET)
            {
                     USART_ClearFlag(USART1,USART_FLAG_ORE); //Ïè¶áSR
                     USART_ReceiveData(USART1); //Ôù¶áDR
            }

            USART1_Rec_Cnt= DMA_Rec_Len-DMA_GetCurrDataCounter(DMA2_Stream5);
            USART1_Send(DMA_Rece_Buf,USART1_Rec_Cnt);
            USART_ClearITPendingBit(USART1, USART_IT_IDLE|USART_IT_RXNE|USART_IT_TC);
      //USART_ITConfig(USART1, USART_IT_IDLE , ENABLE);
/* Clear all DMA Streams flags */
DMA_ClearFlag(DMA2_Stream5, DMA_FLAG_HTIF2 | DMA_FLAG_TCIF2);

            DMA_SetCurrDataCounter(DMA2_Stream5,DMA_Rec_Len);
            DMA_Cmd(DMA2_Stream5, ENABLE);

      }
}
void NVIC_Configuration(void)
{
  NVIC_InitTypeDef NVIC_InitStructure;
  /*Enable DMA Interrupt
  NVIC_InitStructure.NVIC_IRQChannel = DMA2_Stream5_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);*/
      NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
      NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
}
/*éèÖÃê±Öó*/

void RCC_Configuration(void)
{
      RCC_DeInit();

      RCC_HSICmd(ENABLE);
      while (RCC_GetFlagStatus(RCC_FLAG_HSIRDY) == RESET){}

      RCC_HCLKConfig(RCC_SYSCLK_Div1);
      RCC_PCLK1Config(RCC_HCLK_Div4);
      RCC_PCLK2Config(RCC_HCLK_Div2);

      FLASH_SetLatency(FLASH_Latency_7) ;
      FLASH_PrefetchBufferCmd(ENABLE);

      RCC_PLLConfig(RCC_PLLSource_HSI, 16, 240, 2, 5);

      RCC_PLLCmd(ENABLE);
      while (RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET){}
      RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);

      RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE);
      RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);
}

            /*GPIOéèÖÃ*/

void GPIO_Configuration(void)
{
      GPIO_InitTypeDef  GPIO_InitStructure;

      GPIO_PinAFConfig(GPIOC, GPIO_PinSource6, GPIO_AF_USART1);
  GPIO_PinAFConfig(GPIOC, GPIO_PinSource7, GPIO_AF_USART1);

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;       //íÆíìêä3ö
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP ;             //éÏà-êäèë

      GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
  GPIO_Init(GPIOC, &GPIO_InitStructure);
      GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7 ;
  GPIO_Init(GPIOC, &GPIO_InitStructure);
}

            /*USARTéèÖÃ*/

void USART_Configuration(void)
{
      USART_InitTypeDef USART_InitStructure;

      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;
      USART_ClearFlag(USART1, USART_FLAG_TC);
  USART_Init(USART1, &USART_InitStructure);
  USART_ITConfig(USART1, USART_IT_IDLE , ENABLE);
      //USART_ITConfig(USART1, USART_IT_RXNE , ENABLE);
  USART_Cmd(USART1, ENABLE);
}
void USART1_Send(u8 *buf,u8 len)
{
      u8 t;
      for(t=0;t<len;t++)             //Ñ-»··￠Ëíêy¾Y
      {
            while(USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET);
            USART_SendData(USART1,buf[t]);
      }
      while(USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET);
}
void USART1_SendString(uint8_t *ch)
{
      while(*ch!=0)
      {
            while(!USART_GetFlagStatus(USART1, USART_FLAG_TXE));
            USART_SendData(USART1, *ch);
            ch++;
      }
}

收到的数据与发送的相差太大，求大神帮帮忙啊

赞收藏评论3 发布时间：2016-3-17 10:22

3个回答

power568 回答时间：2016-3-17 12:30:20

  是么意思，是单次相差大，还是总数
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
以上大小更改为byte，
  DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
更改为Normal试试看。

另：建议不要再接收中断中立即发送数据!!!

祝你好运...