STM32F407驱动OV7670代码

以下是基于STM32F407的OV7670驱动代码示例，可以供您参考：

#include "stm32f4xx.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_rcc.h"
#include "stm32f4xx_dma.h"
#include "stm32f4xx_dcmi.h"
#include "stdbool.h"

// 定义DCMI，DMA以及NVIC相关变量
DCMI_InitTypeDef DCMI_InitStructure;
DMA_InitTypeDef DMA_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;

// OV7670采集分辨率为160*120
#define WIDTH  160
#define HEIGHT 120
#define BUFFER_SIZE WIDTH * HEIGHT * 2

uint8_t buffer[2][BUFFER_SIZE];
volatile uint8_t buffer_index = 0;

// DCMI中断处理函数
void DCMI_IRQHandler(void) {
    if (DCMI_GetITStatus(DCMI_IT_FRAME) != RESET) {
        // 清除帧中断标志
        DCMI_ClearITPendingBit(DCMI_IT_FRAME);
        // 开始DMA传输
        DMA_Cmd(DMA2_Stream1, ENABLE);
    }
}

// DMA传输完成中断处理函数
void DMA2_Stream1_IRQHandler(void) {
    if (DMA_GetITStatus(DMA2_Stream1, DMA_IT_TCIF1) != RESET) {
        // 清除传输完成中断标志
        DMA_ClearITPendingBit(DMA2_Stream1, DMA_IT_TCIF1);
        // 关闭DMA传输
        DMA_Cmd(DMA2_Stream1, DISABLE);
        // 切换缓冲区
        buffer_index ^= 1;
    }
}

// 初始化DCMI
void DCMI_Init(void) {
    // 打开DCMI时钟
    RCC_AHB2PeriphClockCmd(RCC_AHB2Periph_DCMI, ENABLE);

    // 初始化DCMI
    DCMI_InitStructure.DCMI_CaptureMode = DCMI_CaptureMode_Continuous;
    DCMI_InitStructure.DCMI_SynchroMode = DCMI_SynchroMode_Hardware;
    DCMI_InitStructure.DCMI_PCKPolarity = DCMI_PCKPolarity_Falling;
    DCMI_InitStructure.DCMI_VSPolarity = DCMI_VSPolarity_High;
    DCMI_InitStructure.DCMI_HSPolarity = DCMI_HSPolarity_High;
    DCMI_InitStructure.DCMI_CaptureRate = DCMI_CaptureRate_All_Frame;
    DCMI_InitStructure.DCMI_ExtendedDataMode = DCMI_ExtendedDataMode_8b;
    DCMI_Init(&DCMI_InitStructure);

    // 使能帧中断
    DCMI_ITConfig(DCMI_IT_FRAME, ENABLE);

    // 初始化NVIC
    NVIC_InitStructure.NVIC_IRQChannel = DCMI_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    // 打开DMA时钟
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);

    // 初始化DMA
    DMA_InitStructure.DMA_Channel = DMA_Channel_1;
    DMA_InitStructure.DMA_PeripheralBaseAddr = 0x50050028; // DCMI_DR
    DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)buffer[buffer_index ^ 1];
    DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
    DMA_InitStructure.DMA_BufferSize = BUFFER_SIZE / 4;
    DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
    DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
    DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
    DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word;
    DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
    DMA_InitStructure.DMA_Priority = DMA_Priority_VeryHigh;
    DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Enable;
    DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
    DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
    DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
    DMA_Init(DMA2_Stream1, &DMA_InitStructure);

    // 使能DMA传输完成中断
    DMA_ITConfig(DMA2_Stream1, DMA_IT_TC, ENABLE);

    // 初始化NVIC
    NVIC_InitStructure.NVIC_IRQChannel = DMA2_Stream1_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

// 初始化GPIO
void GPIO_Init(void) {
    GPIO_InitTypeDef GPIO_InitStructure;

    // 打开GPIO时钟
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA | RCC_AHB1Periph_GPIOB | RCC_AHB1Periph_GPIOC | RCC_AHB1Periph_GPIOE, ENABLE);

    // 配置DCMI相关引脚
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource4, GPIO_AF_DCMI);  // DCMI_HSYNC
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource6, GPIO_AF_DCMI);  // DCMI_PIXCLK
    GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_DCMI);  // DCMI_VSYNC
    GPIO_PinAFConfig(GPIOC, GPIO_PinSource6, GPIO_AF_DCMI);  // DCMI_D5
    GPIO_PinAFConfig(GPIOC, GPIO_PinSource7, GPIO_AF_DCMI);  // DCMI_D6
    GPIO_PinAFConfig(GPIOE, GPIO_PinSource0, GPIO_AF_DCMI);  // DCMI_D2
    GPIO_PinAFConfig(GPIOE, GPIO_PinSource1, GPIO_AF_DCMI);  // DCMI_D3
    GPIO_PinAFConfig(GPIOE, GPIO_PinSource4, GPIO_AF_DCMI);  // DCMI_D4
    GPIO_PinAFConfig(GPIOE, GPIO_PinSource5, GPIO_AF_DCMI);  // DCMI_D7

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4 | GPIO_Pin_6;   // DCMI_HSYNC, DCMI_PIXCLK
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
    GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;                // DCMI_VSYNC
    GPIO_Init(GPIOB, &GPIO_InitStructure);

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;   // DCMI_D5, DCMI_D6
    GPIO_Init(GPIOC, &GPIO_InitStructure);

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_4 | GPIO_Pin_5; // DCMI_D2, DCMI_D3, DCMI_D4, DCMI_D7
    GPIO_Init(GPIOE, &GPIO_InitStructure);

    // 配置控制LED的GPIO
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
    GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(GPIOE, &GPIO_InitStructure);
}

int main(void) {
    // 初始化系统时钟
    RCC_DeInit();
    SystemInit();

    // 初始化GPIO
    GPIO_Init();

    // 初始化DCMI
    DCMI_Init();

    // 启动DCMI
    DCMI_Cmd(ENABLE);

    while (true) {
        // 切换LED状态
        GPIO_ToggleBits(GPIOE, GPIO_Pin_12);

        // 等待DMA传输完成
        while (DMA_GetFlagStatus(DMA2_Stream1, DMA_FLAG_TCIF1) == RESET);

        // 处理采集到的数据
        // ...

        // 清除传输完成标志
        DMA_ClearFlag(DMA2_Stream1, DMA_FLAG_TCIF1);
    }
}

需要注意的是，OV7670的输出格式为YUV422，每两个像素共用一个Y值，对应一个U和一个V值。因此，需要在处理采集到的数据时进行YUV422转RGB888的处理。具体的转换算法可以在互联网上查找相关资料。