为什么我的串口2用不了DMA方式接收

songquicken

void uart2_init(u32 bound,u8 DMA) //?®??2??????????

{

//GPIO?????è??

  GPIO_InitTypeDef GPIO_InitStructure;

USART_InitTypeDef USART_InitStructure;

NVIC_InitTypeDef NVIC_InitStructure;

// DMA_InitTypeDef DMA_InitStructure;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2,ENABLE);  //????USART2

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO,ENABLE); //??????????????GPIOA?±??

 

  USART_DeInit(USART2);  //?????®??2

//USART2_TX   PA.2

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2; //PA.2

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //???????ì????

GPIO_Init(GPIOA, &GPIO_InitStructure); //??????PA2

//USART2_RX  A.3

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3; //PA3

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;//????????

GPIO_Init(GPIOA, &GPIO_InitStructure);  //??????PA3

  //Usart2 NVIC ????

  NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=1;  //??????????3

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; //×???????0

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;   //IRQ?¨??????

NVIC_Init(&NVIC_InitStructure); //?ù?????¨????????????VIC?????÷

  

  //USART ???????è??

USART_InitStructure.USART_BaudRate = bound;         //??°??è????9600;

USART_InitStructure.USART_WordLength = USART_WordLength_9b;           //×??¤??8??????????

USART_InitStructure.USART_StopBits  = USART_StopBits_1;              //??????????

USART_InitStructure.USART_Parity = USART_Parity_No;               //?????????é??

USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//???????????÷????

USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; //??·????? 

USART_Init(USART2, &USART_InitStructure);  //???????®??2

if (DMA){

USART_ITConfig(USART2, USART_IT_TXE, DISABLE);   //??±?·???????

USART_ITConfig(USART2,USART_IT_RXNE,DISABLE);    //??±?????????

USART_ITConfig(USART2,USART_IT_IDLE,ENABLE);     //????????????????

  USART_Cmd(USART2, ENABLE);                       //?????®??2

    USART2_DMA_RX();

} 

else

{

USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);    //????????????

        USART_ITConfig(USART2,USART_IT_IDLE,DISABLE);     //??±????????????? 

//USART_ITConfig(USART2, USART_IT_TXE, ENABLE);   //????·???????

USART_Cmd(USART2, ENABLE);                      //?????®??2

}

void USART2_DMA_RX(void)

{

//?®????DMA????

DMA_InitTypeDef DMA_InitStructure;

 NVIC_InitTypeDef NVIC_InitStructure;

 NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel6_IRQn;  

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3;  

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;  

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;  

NVIC_Init(&NVIC_InitStructure);  

RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);//????DMA?±??

   DMA_Cmd(DMA1_Channel6,DISABLE);  //?????¨??

DMA_DeInit(DMA1_Channel6);   //DMA1?¨??????

DMA_InitStructure.DMA_PeripheralBaseAddr = (u32)(&USART2->DR);   //???è???·

DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)RXDData;   //???????·

DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;        //dma????·??ò???ò

DMA_InitStructure.DMA_BufferSize = 3;     

DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;        

DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;     

DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; //???è????×??¤

DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;     //????????×??¤

DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;               //?è??DMA??????????

DMA_InitStructure.DMA_Priority = DMA_Priority_VeryHigh; //?è??DMA????????±?

DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;             //?è??DMA??2??memory????±??????à·???

DMA_Init(DMA1_Channel6,&DMA_InitStructure);

DMA_Cmd(DMA1_Channel6,ENABLE);  //?????¨??

      USART_DMACmd(USART2,USART_DMAReq_Rx,ENABLE);        //????DMA·???????

}

void USART2_IRQHandler(void)                              

{  

  // uint32_t temp = 0;

    if(USART_GetITStatus(USART2, USART_IT_IDLE)==SET)  //???????????

{

//temp = USART2->SR;   //??SR,???DR????

// temp = USART2->DR; //?USART_IT_IDLE??

LED1=~LED1;

DMA_Cmd(DMA1_Channel6,DISABLE);   //??DMA??,??????????

DMA_Cmd(DMA1_Channel6,ENABLE);  //??DMA??

    }

用DMA方式不行，用中断方式就可以，是不是哪里不对，菜鸟求助

正点原子

帮顶。。。。

songquicken

回复【2楼】正点原子:
---------------------------------
还有只要开启这句
     USART_ITConfig(USART2, USART_IT_IDLE , ENABLE);        //开启空闲中断
一接收数据系统就挂掉了

正点原子

songquicken 发表于 2015-12-25 10:10
回复【2楼】正点原子:
---------------------------------
还有只要开启这句
    &nbs ...

仿真一下了