ov5640摄像头使用心得

配置总共分以下几步：
一：硬件初始化
OV5640_HW_Init();

void OV5640_HW_Init(void)
{
	  GPIO_InitTypeDef GPIO_InitStructure;
	  I2C_InitTypeDef  I2C_InitStruct;

	  /***DCMI引脚配置***/
	  /* 使能DCMI时钟 */
	  RCC_AHB1PeriphClockCmd(DCMI_PWDN_GPIO_CLK|DCMI_RST_GPIO_CLK|DCMI_VSYNC_GPIO_CLK | DCMI_HSYNC_GPIO_CLK | DCMI_PIXCLK_GPIO_CLK|
			  DCMI_D0_GPIO_CLK| DCMI_D1_GPIO_CLK| DCMI_D2_GPIO_CLK| DCMI_D3_GPIO_CLK|
			  DCMI_D4_GPIO_CLK| DCMI_D5_GPIO_CLK| DCMI_D6_GPIO_CLK| DCMI_D7_GPIO_CLK, ENABLE);

	  /*控制/同步信号线*/
	  GPIO_InitStructure.GPIO_Pin = DCMI_VSYNC_GPIO_PIN;
	  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(DCMI_VSYNC_GPIO_PORT, &GPIO_InitStructure);
	  GPIO_PinAFConfig(DCMI_VSYNC_GPIO_PORT, DCMI_VSYNC_PINSOURCE, DCMI_VSYNC_AF);

	  GPIO_InitStructure.GPIO_Pin = DCMI_HSYNC_GPIO_PIN ;
	  GPIO_Init(DCMI_HSYNC_GPIO_PORT, &GPIO_InitStructure);
	  GPIO_PinAFConfig(DCMI_HSYNC_GPIO_PORT, DCMI_HSYNC_PINSOURCE, DCMI_HSYNC_AF);

	  GPIO_InitStructure.GPIO_Pin = DCMI_PIXCLK_GPIO_PIN ;
	  GPIO_Init(DCMI_PIXCLK_GPIO_PORT, &GPIO_InitStructure);
	  GPIO_PinAFConfig(DCMI_PIXCLK_GPIO_PORT, DCMI_PIXCLK_PINSOURCE, DCMI_PIXCLK_AF);
    
		/*数据信号*/
	  GPIO_InitStructure.GPIO_Pin = DCMI_D0_GPIO_PIN ;
	  GPIO_Init(DCMI_D0_GPIO_PORT, &GPIO_InitStructure);
	  GPIO_PinAFConfig(DCMI_D0_GPIO_PORT, DCMI_D0_PINSOURCE, DCMI_D0_AF);

	  GPIO_InitStructure.GPIO_Pin = DCMI_D1_GPIO_PIN ;
	  GPIO_Init(DCMI_D1_GPIO_PORT, &GPIO_InitStructure);
	  GPIO_PinAFConfig(DCMI_D1_GPIO_PORT, DCMI_D1_PINSOURCE, DCMI_D1_AF);

	  GPIO_InitStructure.GPIO_Pin = DCMI_D2_GPIO_PIN ;
	  GPIO_Init(DCMI_D2_GPIO_PORT, &GPIO_InitStructure);
	  GPIO_PinAFConfig(DCMI_D2_GPIO_PORT, DCMI_D2_PINSOURCE, DCMI_D2_AF);

	  GPIO_InitStructure.GPIO_Pin = DCMI_D3_GPIO_PIN ;
	  GPIO_Init(DCMI_D3_GPIO_PORT, &GPIO_InitStructure);
	  GPIO_PinAFConfig(DCMI_D3_GPIO_PORT, DCMI_D3_PINSOURCE, DCMI_D3_AF);

	  GPIO_InitStructure.GPIO_Pin = DCMI_D4_GPIO_PIN ;
	  GPIO_Init(DCMI_D4_GPIO_PORT, &GPIO_InitStructure);
	  GPIO_PinAFConfig(DCMI_D4_GPIO_PORT, DCMI_D4_PINSOURCE, DCMI_D4_AF);

	  GPIO_InitStructure.GPIO_Pin = DCMI_D5_GPIO_PIN ;
	  GPIO_Init(DCMI_D5_GPIO_PORT, &GPIO_InitStructure);
	  GPIO_PinAFConfig(DCMI_D5_GPIO_PORT, DCMI_D5_PINSOURCE, DCMI_D5_AF);

	  GPIO_InitStructure.GPIO_Pin = DCMI_D6_GPIO_PIN ;
	  GPIO_Init(DCMI_D6_GPIO_PORT, &GPIO_InitStructure);
	  GPIO_PinAFConfig(DCMI_D6_GPIO_PORT, DCMI_D6_PINSOURCE, DCMI_D6_AF);

	  GPIO_InitStructure.GPIO_Pin = DCMI_D7_GPIO_PIN ;
	  GPIO_Init(DCMI_D7_GPIO_PORT, &GPIO_InitStructure);
	  GPIO_PinAFConfig(DCMI_D7_GPIO_PORT, DCMI_D7_PINSOURCE, DCMI_D7_AF);



      GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
			GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
			GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
			GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
      GPIO_InitStructure.GPIO_Pin = DCMI_PWDN_GPIO_PIN ;
      GPIO_Init(DCMI_PWDN_GPIO_PORT, &GPIO_InitStructure);
      GPIO_InitStructure.GPIO_Pin = DCMI_RST_GPIO_PIN ;
      GPIO_Init(DCMI_RST_GPIO_PORT, &GPIO_InitStructure);
      /*PWDN引脚，高电平关闭电源，低电平供电*/
     
      GPIO_ResetBits(DCMI_RST_GPIO_PORT,DCMI_RST_GPIO_PIN);
      GPIO_SetBits(DCMI_PWDN_GPIO_PORT,DCMI_PWDN_GPIO_PIN);
       
      Delay(10);
      
      GPIO_ResetBits(DCMI_PWDN_GPIO_PORT,DCMI_PWDN_GPIO_PIN);
      //先拉低RST, 关闭电源10ms，然后打开电源， 等待10ms，此时复位完毕，然后RST拉高开始工作！
      Delay(10);
      
      GPIO_SetBits(DCMI_RST_GPIO_PORT,DCMI_RST_GPIO_PIN);
      
	  /****** 配置I2C，使用I2C与摄像头的SCCB接口通讯*****/
	 /* 使能I2C时钟 */
	  RCC_APB1PeriphClockCmd(CAMERA_I2C_CLK, ENABLE);
	  /* 使能I2C使用的GPIO时钟 */
	  RCC_AHB1PeriphClockCmd(CAMERA_I2C_SCL_GPIO_CLK|CAMERA_I2C_SDA_GPIO_CLK, ENABLE);
	  /* 配置引脚源 */
	  GPIO_PinAFConfig(CAMERA_I2C_SCL_GPIO_PORT, CAMERA_I2C_SCL_SOURCE, CAMERA_I2C_SCL_AF);
	  GPIO_PinAFConfig(CAMERA_I2C_SDA_GPIO_PORT, CAMERA_I2C_SDA_SOURCE, CAMERA_I2C_SDA_AF);

	  /* 初始化GPIO */
	  GPIO_InitStructure.GPIO_Pin = CAMERA_I2C_SCL_PIN ;
	  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
	  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
	  GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
	  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
	  GPIO_Init(CAMERA_I2C_SCL_GPIO_PORT, &GPIO_InitStructure);
	  GPIO_PinAFConfig(CAMERA_I2C_SCL_GPIO_PORT, CAMERA_I2C_SCL_SOURCE, CAMERA_I2C_SCL_AF);

	  GPIO_InitStructure.GPIO_Pin = CAMERA_I2C_SDA_PIN ;
	  GPIO_Init(CAMERA_I2C_SDA_GPIO_PORT, &GPIO_InitStructure);

	  /*初始化I2C模式 */
	  I2C_DeInit(CAMERA_I2C); 

	  I2C_InitStruct.I2C_Mode = I2C_Mode_I2C;
	  I2C_InitStruct.I2C_DutyCycle = I2C_DutyCycle_2;
	  I2C_InitStruct.I2C_OwnAddress1 = 0xFE;
	  I2C_InitStruct.I2C_Ack = I2C_Ack_Enable;
	  I2C_InitStruct.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
	  I2C_InitStruct.I2C_ClockSpeed = 400000;

	  /* 写入配置 */
	  I2C_Init(CAMERA_I2C, &I2C_InitStruct);
		
		 /* 使能I2C */
	  I2C_Cmd(CAMERA_I2C, ENABLE);
      
    Delay(50);
}

二：判断摄像头是否已经挂载

OV5640_ReadID(&OV5640_IDStruct);
	if(OV5640_IDStruct.PIDH == 0x56)
	{
		printf("OV5640 IS MOUNTED!\r\n");
	}

三：颜色配置

void OV5640_RGB565Config(void)
{
  uint32_t i;
  
	/*摄像头复位*/
  OV5640_Reset();
  /* 写入寄存器配置 */
  /* Initialize OV5640   Set to output RGB565 */
		for(i=0; i<(sizeof(RGB565_Init)/4); i++)
  {
    OV5640_WriteReg(RGB565_Init[i][0], RGB565_Init[i][1]);
    sensor_reg[i] = OV5640_ReadReg(RGB565_Init[i][0]);
		
		CAMERA_DEBUG("sensor_reg[0x%x]:%x-%x\n",RGB565_Init[i][0],RGB565_Init[i][1],sensor_reg[i]);

  }

  Delay_ms(500);
    
  if(img_width == 320)
       
    ImageFormat=BMP_320x240;
   
  else if(img_width == 640)
      
    ImageFormat=BMP_640x480;
  
  else if(img_width == 800)
      
    ImageFormat=BMP_800x480;
  
  switch(ImageFormat)
  {
    case BMP_320x240:
    {
      for(i=0; i<(sizeof(RGB565_QVGA)/2); i++)
      {
        OV5640_WriteReg(RGB565_QVGA[i][0], RGB565_QVGA[i][1]);
      }
      break;
    }
    case BMP_640x480:
    {
       for(i=0; i<(sizeof(RGB565_VGA)/2); i++)
      {
        OV5640_WriteReg(RGB565_VGA[i][0], RGB565_VGA[i][1]);
      }
      break;
    }
    case BMP_800x480:
    {
      for(i=0; i<(sizeof(RGB565_WVGA)/2); i++)       //?
      {
        OV5640_WriteReg(RGB565_WVGA[i][0], RGB565_WVGA[i][1]);
      }
      break;
    }
    default:
    {
      for(i=0; i<(sizeof(RGB565_WVGA)/2); i++)
      {
        OV5640_WriteReg(RGB565_WVGA[i][0], RGB565_WVGA[i][1]);
      }
      break;
    }
  }
}

四：性能参数设置

void OV5640_USER_Config(void)
{	
	OV5640_FrameRate_Set(cam_mode.frame_rate);
	Delay_ms(100);

//	OV5640_ISPSize_Set(cam_mode.cam_isp_sx,
//											 cam_mode.cam_isp_sy,
//											 cam_mode.cam_isp_width,
//											 cam_mode.cam_isp_height);
//	Delay(100);

    OV5640_OutSize_Set(cam_mode.scaling,
												cam_mode.cam_out_sx,
												cam_mode.cam_out_sy,
												cam_mode.cam_out_width,
												cam_mode.cam_out_height);
	Delay(100);
	OV5640_BrightnessConfig(cam_mode.brightness);
	Delay(100);

	OV5640_Color_Saturation(cam_mode.saturation);
	Delay(100);

	OV5640_ContrastConfig(cam_mode.contrast);
	Delay(100);

	OV5640_Exposure(cam_mode.exposure);
	Delay(100);

	OV5640_LightMode(cam_mode.light_mode);
	Delay(100);

	OV5640_SpecialEffects(cam_mode.effect);	
	Delay(100);

//	Delay(500);
}

五：DCMI以及DMA配置

void OV5640_Init(void) 
{
  DCMI_InitTypeDef DCMI_InitStructure;
	
  NVIC_InitTypeDef NVIC_InitStructure;
	
  
  RCC_AHB2PeriphClockCmd(RCC_AHB2Periph_DCMI, ENABLE);
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE); 
 
  DCMI_InitStructure.DCMI_CaptureMode = DCMI_CaptureMode_Continuous;
  DCMI_InitStructure.DCMI_SynchroMode = DCMI_SynchroMode_Hardware;
  DCMI_InitStructure.DCMI_PCKPolarity = DCMI_PCKPolarity_Rising;
  DCMI_InitStructure.DCMI_VSPolarity = DCMI_VSPolarity_High;
  DCMI_InitStructure.DCMI_HSPolarity = DCMI_HSPolarity_Low;
  DCMI_InitStructure.DCMI_CaptureRate = DCMI_CaptureRate_All_Frame;
  DCMI_InitStructure.DCMI_ExtendedDataMode = DCMI_ExtendedDataMode_8b;
  DCMI_Init(&DCMI_InitStructure); 	
	
  OV5640_Start_DMA((uint32_t)LCD_MemoryAdd,160 * 800 * 2 / 4);//每次传输160行
		
	
  NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);
  NVIC_InitStructure.NVIC_IRQChannel = DMA2_Stream1_IRQn ;//DMA数据流中断
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
  DMA_ITConfig(DMA2_Stream1,DMA_IT_TC,ENABLE); 	
	
  /* 配置帧中断，接收到帧同步信号就进入中断 */
  NVIC_InitStructure.NVIC_IRQChannel = DCMI_IRQn ;	//帧中断
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority =0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
  DCMI_ITConfig (DCMI_IT_FRAME,ENABLE);	
	
	
}

六：配置DMA发送完成中断和DCMI帧中断

void DMA2_Stream1_IRQHandler(void)
{
	if(DMA_GetITStatus(DMA2_Stream1, DMA_IT_TCIF1) == SET)
	{
		//DMA_ClearITPendingBit(DMA2_Stream1, DMA_IT_TCIF1);//放在这里不行，不知道为啥
		linenum++;
		if(3 == linenum)
		{
			linenum = 0;
		}
		
		OV5640_Start_DMA(LCD_MemoryAdd + 160*(800 *2*linenum), 160*800 * 2 /4);
		DMA_ClearITPendingBit(DMA2_Stream1, DMA_IT_TCIF1);
	}
}

void DCMI_IRQHandler(void)
{
	if(DCMI_GetITStatus(DCMI_IT_FRAME) == SET)
	{
		DCMI_ClearITPendingBit(DCMI_IT_FRAME);
		linenum = 0;
	}
	
	//OV5640_Start_DMA(LCD_MemoryAdd, 800 * 2 /4);
	
}

因为DMA每次发送的项数不能超过65535， 每一项的大小为数据源的宽度，即PSIZE = 字，因此每次控制传输不能超过65535字，而每一行的大小为800 x 2 / 4（字），那么160 x 800 x 2 / 4 = 64000（字） < 65535(字）， 这样分三次传输完一帧（480行）， 每次传输160行，有效减少了出入DMA中断的次数，每帧进入DMA中断三次，然后在DCMI帧中断里重新开始新的一帧传输，保证同步。

六：开始捕捉

DCMI_Cmd(ENABLE); 
DCMI_CaptureCmd(ENABLE); 

注：
这里我的LCD第一层设置像素格式为RGB565,第二层设置为ARGB1555（可以实现字幕在画面上方的效果）,
LTDC时钟经测试25M合适
效果图：

来源：CSDN

作者：一个人的团队

链接：https://blog.csdn.net/weixin_43527214/article/details/104728612