STM32F407使用标准库实现USART3使用DMA进行数据的循环发送和接收

以下是使用标准库实现USART3使用DMA进行数据的循环发送和接收的步骤：

1. 初始化USART3

RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);

GPIO_PinAFConfig(GPIOB, GPIO_PinSource10, GPIO_AF_USART3);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource11, GPIO_AF_USART3);

GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_11;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOB, &GPIO_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_Init(USART3, &USART_InitStructure);

USART_Cmd(USART3, ENABLE);

2. 初始化DMA

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1, ENABLE);

DMA_InitTypeDef DMA_InitStructure;

DMA_DeInit(DMA1_Stream3);
DMA_InitStructure.DMA_Channel = DMA_Channel_4;
DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;
DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)tx_buffer;
DMA_InitStructure.DMA_BufferSize = TX_BUFFER_SIZE;
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(USART3->DR);
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_High;
DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
DMA_Init(DMA1_Stream3, &DMA_InitStructure);

DMA_Cmd(DMA1_Stream3, ENABLE);

DMA_DeInit(DMA1_Stream1);
DMA_InitStructure.DMA_Channel = DMA_Channel_4;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)rx_buffer;
DMA_InitStructure.DMA_BufferSize = RX_BUFFER_SIZE;
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(USART3->DR);
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_Circular;
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
DMA_Init(DMA1_Stream1, &DMA_InitStructure);

DMA_Cmd(DMA1_Stream1, ENABLE);

3. 启动DMA发送和接收

USART_DMACmd(USART3, USART_DMAReq_Tx, ENABLE);
USART_DMACmd(USART3, USART_DMAReq_Rx, ENABLE);

4. 发送数据

while (1) {
    for (int i = 0; i < TX_BUFFER_SIZE; i++) {
        tx_buffer[i] = i;
    }
    DMA_Cmd(DMA1_Stream3, DISABLE);
    DMA_SetCurrDataCounter(DMA1_Stream3, TX_BUFFER_SIZE);
    DMA_Cmd(DMA1_Stream3, ENABLE);
    while (DMA_GetFlagStatus(DMA1_Stream3, DMA_FLAG_TCIF3) == RESET);
    DMA_ClearFlag(DMA1_Stream3, DMA_FLAG_TCIF3);
}

5. 接收数据

while (1) {
    while (DMA_GetFlagStatus(DMA1_Stream1, DMA_FLAG_TCIF1) == RESET);
    DMA_ClearFlag(DMA1_Stream1, DMA_FLAG_TCIF1);
    for (int i = 0; i < RX_BUFFER_SIZE; i++) {
        printf("%d ", rx_buffer[i]);
    }
    printf("\r\n");
}