GD32f103 串口DMA模式例子

以下是一个使用GD32f103芯片的串口DMA模式例子，可以帮助你快速开始使用此功能：

#include "gd32f10x.h"

#define USART0_DR_ADDRESS ((uint32_t)0x40013804)
#define USART1_DR_ADDRESS ((uint32_t)0x40004404)

#define BUFFER_SIZE 256

uint8_t TxBuffer[BUFFER_SIZE];
uint8_t RxBuffer[BUFFER_SIZE];

void RCC_Configuration(void)
{
    /* 使能USART0和DMA1的时钟 */
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART0, ENABLE);
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
}

void GPIO_Configuration(void)
{
    /* 使能USART0的GPIO时钟 */
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);

    /* 配置USART0的TX引脚为复用推挽输出 */
    GPIO_InitPara GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Pin = GPIO_PIN_9;
    GPIO_InitStructure.GPIO_Speed = GPIO_SPEED_50MHZ;
    GPIO_InitStructure.GPIO_Mode = GPIO_MODE_AF_PP;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    /* 配置USART0的RX引脚为浮空输入 */
    GPIO_InitStructure.GPIO_Pin = GPIO_PIN_10;
    GPIO_InitStructure.GPIO_Mode = GPIO_MODE_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
}

void USART_Configuration(void)
{
    /* 配置USART0 */
    USART_InitPara 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_TX_RX;
    USART_Init(USART0, &USART_InitStructure);

    /* 使能USART0的DMA发送和DMA接收 */
    USART_DMACmd(USART0, USART_DMAReq_Tx | USART_DMAReq_Rx, ENABLE);
}

void DMA_Configuration(void)
{
    /* 配置DMA1通道4为USART0的TX通道 */
    DMA_InitPara DMA_InitStructure;
    DMA_InitStructure.DMA_PeripheralBaseAddr = USART0_DR_ADDRESS;
    DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)TxBuffer;
    DMA_InitStructure.DMA_DIR = DMA_DIR_PERIPHERALDST;
    DMA_InitStructure.DMA_BufferSize = BUFFER_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_NORMAL;
    DMA_InitStructure.DMA_Priority = DMA_PRIORITY_HIGH;
    DMA_InitStructure.DMA_M2M = DMA_M2M_DISABLE;
    DMA_Init(DMA1_Channel4, &DMA_InitStructure);

    /* 配置DMA1通道5为USART0的RX通道 */
    DMA_InitStructure.DMA_PeripheralBaseAddr = USART0_DR_ADDRESS;
    DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)RxBuffer;
    DMA_InitStructure.DMA_DIR = DMA_DIR_PERIPHERALSRC;
    DMA_InitStructure.DMA_BufferSize = BUFFER_SIZE;
    DMA_Init(DMA1_Channel5, &DMA_InitStructure);

    /* 使能DMA1通道4和DMA1通道5 */
    DMA_Cmd(DMA1_Channel4, ENABLE);
    DMA_Cmd(DMA1_Channel5, ENABLE);
}

int main(void)
{
    /* 系统时钟配置 */
    SystemInit();

    /* RCC配置 */
    RCC_Configuration();

    /* GPIO配置 */
    GPIO_Configuration();

    /* USART配置 */
    USART_Configuration();

    /* DMA配置 */
    DMA_Configuration();

    while (1)
    {
        /* 发送数据 */
        for (uint16_t i = 0; i < BUFFER_SIZE; i++)
        {
            TxBuffer[i] = i;
        }

        while (DMA_GetFlagStatus(DMA1_FLAG_TC4) == RESET);

        /* 接收数据 */
        while (DMA_GetFlagStatus(DMA1_FLAG_TC5) == RESET);

        /* 处理接收到的数据 */
        for (uint16_t i = 0; i < BUFFER_SIZE; i++)
        {
            if (RxBuffer[i] != i)
            {
                /* 处理接收到的数据出错 */
            }
        }
    }
}

这个例子使用USART0的DMA模式进行数据的发送和接收，并且使用了DMA1通道4和DMA1通道5。在主循环中，它会先发送一个有序的数据包，然后等待DMA发送完成，再接收一个数据包，并验证接收到的数据是否正确。