STM32的SPI3使用DMA的程序

以下是一个使用STM32的SPI3和DMA控制器进行数据传输的程序：

#include "stm32f4xx.h"

#define BUFFER_SIZE 100

uint8_t txBuffer[BUFFER_SIZE];
uint8_t rxBuffer[BUFFER_SIZE];

void SPI3_DMA_Init(void)
{
    // 使能SPI3和DMA2时钟
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI3, ENABLE);
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);

    // 配置SPI3的GPIO口
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3 | GPIO_Pin_4 | GPIO_Pin_5;
    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_NOPULL;
    GPIO_Init(GPIOB, &GPIO_InitStructure);

    // 配置SPI3的工作模式
    SPI_InitTypeDef SPI_InitStructure;
    SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
    SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
    SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
    SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;
    SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;
    SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
    SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_256;
    SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
    SPI_InitStructure.SPI_CRCPolynomial = 7;
    SPI_Init(SPI3, &SPI_InitStructure);

    // 配置DMA2_Stream2
    DMA_InitTypeDef DMA_InitStructure;
    DMA_InitStructure.DMA_Channel = DMA_Channel_0;
    DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&SPI3->DR;
    DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)rxBuffer;
    DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
    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_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(DMA2_Stream2, &DMA_InitStructure);

    // 使能DMA2_Stream2和SPI3的DMA接收
    DMA_Cmd(DMA2_Stream2, ENABLE);
    SPI_I2S_DMACmd(SPI3, SPI_I2S_DMAReq_Rx, ENABLE);

    // 使能SPI3
    SPI_Cmd(SPI3, ENABLE);
}

int main(void)
{
    // 初始化SPI3和DMA2
    SPI3_DMA_Init();

    // 初始化发送缓冲区
    for (int i = 0; i < BUFFER_SIZE; i++) {
        txBuffer[i] = i;
    }

    // 发送数据
    while (1) {
        SPI_I2S_DMACmd(SPI3, SPI_I2S_DMAReq_Tx, ENABLE);
        DMA_Cmd(DMA2_Stream2, DISABLE);
        DMA_SetCurrDataCounter(DMA2_Stream2, BUFFER_SIZE);
        DMA_Cmd(DMA2_Stream2, ENABLE);

        // 等待传输完成
        while (DMA_GetFlagStatus(DMA2_Stream2, DMA_FLAG_TCIF2) == RESET) {}

        // 清除传输完成标志位
        DMA_ClearFlag(DMA2_Stream2, DMA_FLAG_TCIF2);
    }
}

在该程序中，首先通过SPI3和DMA2初始化函数进行初始化，然后通过循环向SPI3发送数据，发送数据的过程中，先使能SPI3的DMA发送请求，然后等待传输完成。在传输完成时，需要清除DMA传输完成标志位，以便下一次传输。