1 u8 _data1[4];

 2 void Configuration(void)

 3 {

 4   USART_InitTypeDef USART_InitStructure;

 5   DMA_InitTypeDef DMA_InitStructure;

 6   GPIO_InitTypeDef GPIO_InitStructure;

 7   RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);

 8    //TX

 9   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;

10   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

11   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

12   GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;

13   GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;

14   GPIO_Init(GPIOB, &GPIO_InitStructure);

15   //RX

16   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;

17   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

18   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

19   GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;

20   GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;

21   GPIO_Init(GPIOB, &GPIO_InitStructure);

22

23   GPIO_PinAFConfig(GPIOB, GPIO_PinSource10, GPIO_AF_USART3);

24   GPIO_PinAFConfig(GPIOB, GPIO_PinSource11, GPIO_AF_USART3);

25

26   DMA_InitStructure.DMA_Channel = DMA_Channel_4;

27   DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(USART3->DR);

28   DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)_data1;

29   DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;

30   DMA_InitStructure.DMA_BufferSize = 4;

31   DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;

32   DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;

33   DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;

34   DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;

35   DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;

36   DMA_InitStructure.DMA_Priority = DMA_Priority_High;

37   DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;

38   DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;

39   DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;

40   DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;

41   DMA_Init(DMA1_Stream1, &DMA_InitStructure);

42   DMA_Cmd(DMA1_Stream1, ENABLE);

43

44   USART_OverSampling8Cmd(USART3, ENABLE);

45   USART_InitStructure.USART_BaudRate = 38400;

46   USART_InitStructure.USART_WordLength = USART_WordLength_8b;

47   USART_InitStructure.USART_StopBits = USART_StopBits_1;

48   USART_InitStructure.USART_Parity = USART_Parity_No;

49   USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;

50   USART_InitStructure.USART_Mode = USART_Mode_Rx|USART_Mode_Tx;

51   USART_Init(USART3, &USART_InitStructure);

52   USART_DMACmd(USART3, USART_DMAReq_Rx, ENABLE);

53   DMA_Cmd(DMA1_Stream1, ENABLE);

54   USART_Cmd(USART3, ENABLE);

55 }