OV7670摄像头模块核心代码

OV7670是一款非常常见的CMOS图像传感器，常用于嵌入式系统和智能家居等领域。下面是一份OV7670摄像头模块的核心代码，供参考：

#include <Wire.h>
#include "ov7670.h"

// OV7670初始化函数
void ov7670_init() {
  // 初始化I2C总线
  Wire.begin();
  Wire.setClock(100000);

  // 设置寄存器
  ov7670_write_reg(REG_COM7, 0x80); // 复位所有寄存器

  delay(500);

  ov7670_write_reg(REG_CLKRC, 0x01); // 分频器设置为1分频
  ov7670_write_reg(REG_COM11, 0x0A); // PCLK反相，输出低电平
  ov7670_write_reg(REG_TSLB, 0x04); // UYVY格式
  ov7670_write_reg(REG_COM7, 0x14); // QVGA分辨率
  ov7670_write_reg(REG_COM15, 0xD0); // RGB565输出

  ov7670_write_reg(REG_HSTART, 0x16);
  ov7670_write_reg(REG_HSTOP, 0x04B);
  ov7670_write_reg(REG_HREF, 0x24);
  ov7670_write_reg(REG_VSTART, 0x02);
  ov7670_write_reg(REG_VSTOP, 0x01D);
  ov7670_write_reg(REG_VREF, 0x0A);

  ov7670_write_reg(REG_COM10, 0x02); // VSYNC低电平时自动重启
  ov7670_write_reg(REG_MVFP, 0x27); // 翻转图像

  // 启动输出
  ov7670_write_reg(REG_COM13, 0x08); // GAIN和AGC使能
  ov7670_write_reg(REG_COM14, 0x18); // AGC增益设置
  ov7670_write_reg(REG_SCALING_XSC, 0x3a);
  ov7670_write_reg(REG_SCALING_YSC, 0x35);
  ov7670_write_reg(REG_SCALING_DCWCTR, 0x11);
  ov7670_write_reg(REG_SCALING_PCLK_DIV, 0xf0);
  ov7670_write_reg(REG_SCALING_PCLK_DELAY, 0x02);
  ov7670_write_reg(REG_COM11, 0x0A); // PCLK反相，输出低电平
  ov7670_write_reg(REG_CLKRC, 0x01); // 分频器设置为1分频

  ov7670_write_reg(REG_COM10, 0x02); // VSYNC低电平时自动重启
  ov7670_write_reg(REG_TSLB, 0x04); // UYVY格式
  ov7670_write_reg(REG_RGB444, 0x00); // RGB444格式关闭
  ov7670_write_reg(REG_COM15, 0xD0); // RGB565输出
  ov7670_write_reg(REG_COM11, 0x0A); // PCLK反相，输出低电平
  ov7670_write_reg(REG_CLKRC, 0x01); // 分频器设置为1分频

  // 启动输出
  ov7670_write_reg(REG_COM13, 0x08); // GAIN和AGC使能
  ov7670_write_reg(REG_COM14, 0x18); // AGC增益设置
  ov7670_write_reg(REG_COM15, 0xD0); // RGB565输出
  ov7670_write_reg(REG_COM10, 0x02); // VSYNC低电平时自动重启
  ov7670_write_reg(REG_MVFP, 0x27); // 翻转图像

  // 设置寄存器完成后，等待摄像头初始化完成
  delay(500);
}

// 读取OV7670的ID
uint8_t ov7670_read_id() {
  uint8_t id = ov7670_read_reg(REG_MANUF);
  return id;
}

// 读取OV7670的一帧图像
void ov7670_read_frame(uint8_t* buffer) {
  uint16_t count = 0;
  uint8_t line = 0;
  uint8_t pixel = 0;

  // 读取一帧图像数据
  while (line < OV7670_HEIGHT) {
    while (ov7670_read_reg(REG_VSYNC) & BIT_VSYNC) {
      ; // 等待VSYNC信号高电平
    }
    while (!(ov7670_read_reg(REG_VSYNC) & BIT_VSYNC)) {
      ; // 等待VSYNC信号低电平
    }

    // 读取一行图像数据
    for (pixel = 0; pixel < OV7670_WIDTH; pixel += 2) {
      uint16_t data = ov7670_read_data();
      buffer[count++] = data >> 8;
      buffer[count++] = data & 0xFF;
    }

    line++;
  }
}

// 读取OV7670的一帧图像并显示
void ov7670_display_frame() {
  uint8_t buffer[OV7670_WIDTH * OV7670_HEIGHT * 2];
  ov7670_read_frame(buffer);
  TFTscreen.pushImage(0, 0, OV7670_WIDTH, OV7670_HEIGHT, (uint16_t*)buffer);
}

// 读取OV7670的一个寄存器
uint8_t ov7670_read_reg(uint8_t reg) {
  Wire.beginTransmission(OV7670_I2C_ADDR);
  Wire.write(reg);
  Wire.endTransmission(false);

  Wire.requestFrom(OV7670_I2C_ADDR, 1);
  uint8_t value = Wire.read();

  return value;
}

// 写入OV7670的一个寄存器
void ov7670_write_reg(uint8_t reg, uint8_t value) {
  Wire.beginTransmission(OV7670_I2C_ADDR);
  Wire.write(reg);
  Wire.write(value);
  Wire.endTransmission();
}

// 读取OV7670的一个数据
uint16_t ov7670_read_data() {
  uint8_t data1 = ov7670_read_reg(REG_FIFO);
  uint8_t data2 = ov7670_read_reg(REG_FIFO);

  return ((data1 << 8) | data2);
}

这份代码包含了OV7670的初始化、读取ID、读取一帧图像、读取一个寄存器和读取一个数据等基本操作。需要注意的是，这份代码只是一个简单的示例，具体的使用还需要根据实际情况进行调整和修改。