stm32使用dma串口接收数据代码

以下是使用DMA方式接收串口数据的STM32代码示例：

#include "stm32f4xx.h"

#define UART_RX_BUF_SIZE 100

uint8_t uart_rx_buf[UART_RX_BUF_SIZE];
uint8_t uart_rx_len = 0;

void USART2_DMA_Init(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    USART_InitTypeDef USART_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;
    DMA_InitTypeDef DMA_InitStructure;
 
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1, ENABLE);
  
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource3, GPIO_AF_USART2);
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource2, GPIO_AF_USART2);
  
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3 | GPIO_Pin_2;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(GPIOA, &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(USART2, &USART_InitStructure);
  
    USART_ITConfig(USART2, USART_IT_IDLE, ENABLE);
    DMA_InitStructure.DMA_Channel = DMA_Channel_4;
    DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(USART2->DR);
    DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)uart_rx_buf;
    DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
    DMA_InitStructure.DMA_BufferSize = UART_RX_BUF_SIZE;
    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_Full;
    DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
    DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
    DMA_Init(DMA1_Stream5, &DMA_InitStructure);
  
    DMA_Cmd(DMA1_Stream5, ENABLE);
    USART_Cmd(USART2, ENABLE);
  
    while (USART_GetFlagStatus(USART2, USART_FLAG_TC) == RESET);
  
    NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
  
    USART_DMACmd(USART2, USART_DMAReq_Rx, ENABLE);
}

void USART2_IRQHandler(void)
{
    if (USART_GetITStatus(USART2, USART_IT_IDLE) != RESET)
    {
        DMA_Cmd(DMA1_Stream5, DISABLE);
        uart_rx_len = UART_RX_BUF_SIZE - DMA_GetCurrDataCounter(DMA1_Stream5);
        DMA_SetCurrDataCounter(DMA1_Stream5, UART_RX_BUF_SIZE);
        DMA_Cmd(DMA1_Stream5, ENABLE);
        USART_ClearITPendingBit(USART2, USART_IT_IDLE);
    }
}

int main(void)
{
    USART2_DMA_Init();
    while (1);
}

注：以上代码为STM32F4xx系列的代码示例，其他系列的代码略有不同，但基本思路相同。