STM32H750獲取OV2640攝像頭影像及上位機解碼（一維碼&二維碼）
1. 目的
針對靜止拍攝影像場景，實作STM32H750對200萬像素OV2640攝像頭進行影像捕獲，并通過串口將資料送到上位機軟體進行解碼，
本文可作為STM32H7及STM32F7系列驅動OV2640攝像頭的代碼參考，本例程輸出解析度（640×480）是通過DCMI的CROP方式從大圖片中“剪”出，使用者也可以做不同設定“剪"出不同解析度的圖片，
2. 場景引數說明
- 上位機與STM32H750通過USB全速虛擬串口（可用12000000波特率）或UART串口（230400波特率）通訊及接收影像資料，
- STM32H750通過DCMI總線介面與OV2640攝像頭DVP介面連接，通過IIC總線與OV2640 SCCB配置埠連接，并通過GPIO連接控制攝像頭端的Reset和PowerDown管腳，
- STM32H750從OV2640攝像頭獲取640×480解析度的RGB影像，本實驗不針對有SRAM擴展的場景，也不針對直接傳送資料至嵌入式LCD顯示的場景,因此，內部SRAM磁區用于存放一幀資料*（640×480×2 bytes)的空間不足，因此，利用STM32 DCMI CROP功能，獲取多幀影像的不同部分實作拼接效果，并最終將一整幀資料傳送到上位機，
- 開發環境為STM32CUBEIDE（HAL庫）
3. 通訊協議
- 上位機通過串口發送0x01指令到STM32, STM32接收指令后，回復0x55 0xaa xx三個位元組，其中0x55 0xaa指示有效的回復，xx為攝像頭型別說明，便于上位機程式進行后續資料的識別處理，當前xx==0x02為OV2640攝像頭，
- STM32從OV2640攝像頭分幀獲取不同部分并發送整幀640×480×2的RGB565資料到上位機，
- 上位機進行影像的顯示，并可選進行一維碼和二維碼的識別（基于zbar開源庫），
- 簡化型設計，無校驗方式
4. STM32H750時鐘配置
對于需要STM32H750輸出24MHz時鐘給OV2640攝像頭模塊的場景，可以用STM32 MCO功能輸出24MHz時鐘，如果攝像頭模塊自帶晶振，不需要STM32提供時鐘，
5. STM32H750通訊介面配置
USB虛擬串口：
USART1串口配置：
6. 攝像頭介面配置
DCMI介面：
STM32H7的HAL庫DCMI介面,從1.8版本升級1.9以上版本后，配置及函式存在問題，因此這里的引數配置（“Parameter Settings”）部分，會在程式里面重新配置，
而其它部分正常配置：
需要單獨對DCMI介面的HSYNC和VSYNC做輸入GPIO的配置：
OV2640的SCCB介面時序通過STM32的GPIO管腳模擬，不采用專用的IIC管腳，OV2640的Reset和PowerDown信號，也通過2個GPIO進行管理控制，
保存，并生成初始代碼，再進行功能代碼的撰寫，
7. OV2640介面及配置代碼
撰寫ov2640.h檔案：
#include "stm32h7xx_hal.h"
#ifndef _OV2640_H
#define _OV2640_H
//for not open-drain bus
/*
* SIOC: PE7
* SIOD: PE8
* VSYNC: PB7
* HREF: PA4
* PCLK: PA6
* XCLK: PA8//24MHz, optional to use
* D7: PB9
* D6: PB8
* D5: PD3
* D4: PC11
* D3: PE1
* D2: PC8
* D1: PC7
* D0: PC6
* RESET: PD10
* PWDN: PD11
*
*
*/
#define SCCB_SCL_L HAL_GPIO_WritePin(GPIOE,GPIO_PIN_7,GPIO_PIN_RESET)
#define SCCB_SCL_H HAL_GPIO_WritePin(GPIOE,GPIO_PIN_7,GPIO_PIN_SET)
#define SCCB_SDA_L HAL_GPIO_WritePin(GPIOE,GPIO_PIN_8,GPIO_PIN_RESET)
#define SCCB_SDA_H HAL_GPIO_WritePin(GPIOE,GPIO_PIN_8,GPIO_PIN_SET)
#define SCCB_READ_SDA HAL_GPIO_ReadPin(GPIOE, GPIO_PIN_8)
#define SCCB_ID_W 0X60 //OV2640 ID for Write
#define SCCB_ID_R 0X61 //OV2640 ID for Read
#define OV2640_PWDN HAL_GPIO_WritePin(GPIOD,GPIO_PIN_11,GPIO_PIN_SET)
#define OV2640_PWUP HAL_GPIO_WritePin(GPIOD,GPIO_PIN_11,GPIO_PIN_RESET)
#define OV2640_RST HAL_GPIO_WritePin(GPIOD,GPIO_PIN_10,GPIO_PIN_RESET)
#define OV2640_RUN HAL_GPIO_WritePin(GPIOD,GPIO_PIN_10,GPIO_PIN_SET)
#define OV2640_VSYNC HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_7)
#define OV2640_HREF HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_4)
#define OV2640_PCLK HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_6)
void SCCB_Start(void);
void SCCB_Stop(void);
void SCCB_No_Ack(void);
uint8_t SCCB_WR_Byte(uint8_t data);
uint8_t SCCB_RD_Byte(void);
uint8_t SCCB_WR_Reg(uint8_t reg,uint8_t data);
uint8_t SCCB_RD_Reg(uint8_t reg);
uint32_t tickdelay;
void SCCB_SDA_IN(void);
void SCCB_SDA_OUT(void);
#define ticknumber 12*5
void SCCB_Rst(void);
/***********************************/
void OV2640_Auto_Exposure(uint8_t level);
void OV2640_Light_Mode(uint8_t mode);
void OV2640_Color_Saturation(uint8_t sat);
void OV2640_Brightness(uint8_t bright);
void OV2640_Contrast(uint8_t contrast);
void OV2640_Special_Effects(uint8_t eft);
void OV2640_Color_Bar(uint8_t sw);
void OV2640_Window_Set(uint16_t sx,uint16_t sy,uint16_t width,uint16_t height);
uint8_t OV2640_OutSize_Set(uint16_t width,uint16_t height);
uint8_t OV2640_ImageWin_Set(uint16_t offx,uint16_t offy,uint16_t width,uint16_t height);
uint8_t OV2640_ImageSize_Set(uint16_t width,uint16_t height);
void OV2640_RGB565_Mode(void);
void OV2640_UXGA_Init(void);
#endif
撰寫ov2640.c檔案：
#include <ov2640.h>
//for not open-drain bus
void SCCB_Start(void)
{
SCCB_SDA_H;
SCCB_SCL_H;
tickdelay = ticknumber;while(tickdelay--);
SCCB_SDA_L;
tickdelay = ticknumber;while(tickdelay--);
SCCB_SCL_L;
}
void SCCB_Stop(void)
{
SCCB_SDA_L;
tickdelay = ticknumber;while(tickdelay--);
SCCB_SCL_H;
tickdelay = ticknumber;while(tickdelay--);
SCCB_SDA_H;
tickdelay = ticknumber;while(tickdelay--);
}
void SCCB_No_Ack(void)
{
HAL_Delay(1);
SCCB_SDA_H;
SCCB_SCL_H;
tickdelay = ticknumber;while(tickdelay--);
SCCB_SCL_L;
tickdelay = ticknumber;while(tickdelay--);
SCCB_SDA_L;
tickdelay = ticknumber;while(tickdelay--);
}
uint8_t SCCB_WR_Byte(uint8_t dat)
{
uint8_t j,res;
for(j=0;j<8;j++)
{
if(dat&0x80)SCCB_SDA_H;
else SCCB_SDA_L;
dat<<=1;
tickdelay = ticknumber;while(tickdelay--);
SCCB_SCL_H;
tickdelay = ticknumber;while(tickdelay--);
SCCB_SCL_L;
}
SCCB_SDA_IN();
tickdelay = ticknumber;while(tickdelay--);
SCCB_SCL_H;
tickdelay = ticknumber;while(tickdelay--);
if(SCCB_READ_SDA)res=1;
else res=0;
SCCB_SCL_L;
SCCB_SDA_OUT();
return res;
}
uint8_t SCCB_RD_Byte(void)
{
uint8_t temp=0,j;
SCCB_SDA_IN();
for(j=8;j>0;j--)
{
tickdelay = ticknumber;while(tickdelay--);
SCCB_SCL_H;
temp=temp<<1;
if(SCCB_READ_SDA)temp++;
tickdelay = ticknumber;while(tickdelay--);
SCCB_SCL_L;
}
SCCB_SDA_OUT();
return temp;
}
uint8_t SCCB_WR_Reg(uint8_t reg,uint8_t data)
{
uint8_t res=0;
SCCB_Start();
if(SCCB_WR_Byte(SCCB_ID_W))res=1;
tickdelay = ticknumber;while(tickdelay--);
if(SCCB_WR_Byte(reg))res=1;
tickdelay = ticknumber;while(tickdelay--);
if(SCCB_WR_Byte(data))res=1;
SCCB_Stop();
return res;
}
uint8_t SCCB_RD_Reg(uint8_t reg)
{
uint8_t val=0;
SCCB_Start();
SCCB_WR_Byte(SCCB_ID_W);
tickdelay = ticknumber;while(tickdelay--);
SCCB_WR_Byte(reg);
tickdelay = ticknumber;while(tickdelay--);
SCCB_Stop();
tickdelay = ticknumber;while(tickdelay--);
SCCB_Start();
SCCB_WR_Byte(SCCB_ID_R);
tickdelay = ticknumber;while(tickdelay--);
val=SCCB_RD_Byte();
SCCB_No_Ack();
SCCB_Stop();
return val;
}
void SCCB_SDA_IN(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
__HAL_RCC_GPIOE_CLK_ENABLE();
GPIO_InitStruct.Pin = GPIO_PIN_8;
GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
GPIO_InitStruct.Pull = GPIO_PULLUP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
HAL_GPIO_Init(GPIOE, &GPIO_InitStruct);
}
void SCCB_SDA_OUT(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
__HAL_RCC_GPIOE_CLK_ENABLE();
GPIO_InitStruct.Pin = GPIO_PIN_8;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
HAL_GPIO_Init(GPIOE, &GPIO_InitStruct);
}
void SCCB_Rst(void)
{
HAL_GPIO_WritePin(GPIOD,GPIO_PIN_11,GPIO_PIN_RESET) ;
HAL_GPIO_WritePin(GPIOD,GPIO_PIN_10,GPIO_PIN_RESET) ;
HAL_Delay(5);
HAL_GPIO_WritePin(GPIOD,GPIO_PIN_10,GPIO_PIN_SET) ;
HAL_Delay(5);
}
/***********************************/
//UXGA(1600*1200)
const uint8_t ov2640_uxga_init_reg_tbl[][2]=
{
0xff, 0x00,
0x2c, 0xff,
0x2e, 0xdf,
0xff, 0x01,
0x3c, 0x32,
//
0x11, 0x00,
0x09, 0x02,
0x04, 0xD8,
0x13, 0xe5,
0x14, 0x48,
0x2c, 0x0c,
0x33, 0x78,
0x3a, 0x33,
0x3b, 0xfB,
//
0x3e, 0x00,
0x43, 0x11,
0x16, 0x10,
//
0x39, 0x92,
//
0x35, 0xda,
0x22, 0x1a,
0x37, 0xc3,
0x23, 0x00,
0x34, 0xc0,
0x36, 0x1a,
0x06, 0x88,
0x07, 0xc0,
0x0d, 0x87,
0x0e, 0x41,
0x4c, 0x00,
0x48, 0x00,
0x5B, 0x00,
0x42, 0x03,
//
0x4a, 0x81,
0x21, 0x99,
//
0x24, 0x40,
0x25, 0x38,
0x26, 0x82,
0x5c, 0x00,
0x63, 0x00,
0x46, 0x00,
0x0c, 0x3c,
//
0x61, 0x70,
0x62, 0x80,
0x7c, 0x05,
//
0x20, 0x80,
0x28, 0x30,
0x6c, 0x00,
0x6d, 0x80,
0x6e, 0x00,
0x70, 0x02,
0x71, 0x94,
0x73, 0xc1,
0x3d, 0x34,
0x5a, 0x57,
//
0x12, 0x00,//UXGA 1600*1200
0x17, 0x11,
0x18, 0x75,
0x19, 0x01,
0x1a, 0x97,
0x32, 0x36,
0x03, 0x0f,
0x37, 0x40,
//
0x4f, 0xca,
0x50, 0xa8,
0x5a, 0x23,
0x6d, 0x00,
0x6d, 0x38,
//
0xff, 0x00,
0xe5, 0x7f,
0xf9, 0xc0,
0x41, 0x24,
0xe0, 0x14,
0x76, 0xff,
0x33, 0xa0,
0x42, 0x20,
0x43, 0x18,
0x4c, 0x00,
0x87, 0xd5,
0x88, 0x3f,
0xd7, 0x03,
0xd9, 0x10,
0xd3, 0x82,
//
0xc8, 0x08,
0xc9, 0x80,
//
0x7c, 0x00,
0x7d, 0x00,
0x7c, 0x03,
0x7d, 0x48,
0x7d, 0x48,
0x7c, 0x08,
0x7d, 0x20,
0x7d, 0x10,
0x7d, 0x0e,
//
0x90, 0x00,
0x91, 0x0e,
0x91, 0x1a,
0x91, 0x31,
0x91, 0x5a,
0x91, 0x69,
0x91, 0x75,
0x91, 0x7e,
0x91, 0x88,
0x91, 0x8f,
0x91, 0x96,
0x91, 0xa3,
0x91, 0xaf,
0x91, 0xc4,
0x91, 0xd7,
0x91, 0xe8,
0x91, 0x20,
//
0x92, 0x00,
0x93, 0x06,
0x93, 0xe3,
0x93, 0x05,
0x93, 0x05,
0x93, 0x00,
0x93, 0x04,
0x93, 0x00,
0x93, 0x00,
0x93, 0x00,
0x93, 0x00,
0x93, 0x00,
0x93, 0x00,
0x93, 0x00,
//
0x96, 0x00,
0x97, 0x08,
0x97, 0x19,
0x97, 0x02,
0x97, 0x0c,
0x97, 0x24,
0x97, 0x30,
0x97, 0x28,
0x97, 0x26,
0x97, 0x02,
0x97, 0x98,
0x97, 0x80,
0x97, 0x00,
0x97, 0x00,
//
0xc3, 0xef,
0xa4, 0x00,
0xa8, 0x00,
0xc5, 0x11,
0xc6, 0x51,
0xbf, 0x80,
0xc7, 0x10,
0xb6, 0x66,
0xb8, 0xA5,
0xb7, 0x64,
0xb9, 0x7C,
0xb3, 0xaf,
0xb4, 0x97,
0xb5, 0xFF,
0xb0, 0xC5,
0xb1, 0x94,
0xb2, 0x0f,
0xc4, 0x5c,
//
0xc0, 0xc8,
0xc1, 0x96,
0x8c, 0x00,
0x86, 0x3d,
0x50, 0x00,
0x51, 0x90,
0x52, 0x2c,
0x53, 0x00,
0x54, 0x00,
0x55, 0x88,
0x5a, 0x90,
0x5b, 0x2C,
0x5c, 0x05,
0xd3, 0x82,
//
0xc3, 0xed,
0x7f, 0x00,
0xda, 0x09,
0xe5, 0x1f,
0xe1, 0x67,
0xe0, 0x00,
0xdd, 0x7f,
0x05, 0x00,
};
void OV2640_UXGA_Init(void)
{
for(uint32_t i=0; i<sizeof(ov2640_uxga_init_reg_tbl)/2 ; i++)
{
SCCB_WR_Reg(ov2640_uxga_init_reg_tbl[i][0],ov2640_uxga_init_reg_tbl[i][1]);
if(i<10) HAL_Delay(5);
}
}
const uint8_t ov2640_rgb565_reg_tbl[][2]=
{
0xFF, 0x00,
0xDA, 0x09,
0xD7, 0x03,
0xDF, 0x02,
0x33, 0xa0,
0x3C, 0x00,
0xe1, 0x67
};
//OV2640 mode: RGB565
void OV2640_RGB565_Mode(void)
{
uint16_t i=0;
for(i=0;i<(sizeof(ov2640_rgb565_reg_tbl)/2);i++)
{
SCCB_WR_Reg(ov2640_rgb565_reg_tbl[i][0],ov2640_rgb565_reg_tbl[i][1]);
}
}
//AUTOEXPOSURE LEVEL PARAMETER: 5 levels
const static uint8_t OV2640_AUTOEXPOSURE_LEVEL[5][8]=
{
{
0xFF,0x01,
0x24,0x20,
0x25,0x18,
0x26,0x60,
},
{
0xFF,0x01,
0x24,0x34,
0x25,0x1c,
0x26,0x00,
},
{
0xFF,0x01,
0x24,0x3e,
0x25,0x38,
0x26,0x81,
},
{
0xFF,0x01,
0x24,0x48,
0x25,0x40,
0x26,0x81,
},
{
0xFF,0x01,
0x24,0x58,
0x25,0x50,
0x26,0x92,
},
};
//Auto_Exposure
//level:0~4
void OV2640_Auto_Exposure(uint8_t level)
{
uint8_t i;
uint8_t *p=(uint8_t*)OV2640_AUTOEXPOSURE_LEVEL[level];
for(i=0;i<4;i++)
{
SCCB_WR_Reg(p[i*2],p[i*2+1]);
}
}
//Light_Mode
//0:auto
//1:sunny
//2:cloudy
//3:office
//4:home
void OV2640_Light_Mode(uint8_t mode)
{
uint8_t regccval=0X5E;//Sunny
uint8_t regcdval=0X41;
uint8_t regceval=0X54;
switch(mode)
{
case 0://auto
SCCB_WR_Reg(0XFF,0X00);
SCCB_WR_Reg(0XC7,0X10);//AWB ON
return;
case 2://cloudy
regccval=0X65;
regcdval=0X41;
regceval=0X4F;
break;
case 3://office
regccval=0X52;
regcdval=0X41;
regceval=0X66;
break;
case 4://home
regccval=0X42;
regcdval=0X3F;
regceval=0X71;
break;
}
SCCB_WR_Reg(0XFF,0X00);
SCCB_WR_Reg(0XC7,0X40); //AWB OFF
SCCB_WR_Reg(0XCC,regccval);
SCCB_WR_Reg(0XCD,regcdval);
SCCB_WR_Reg(0XCE,regceval);
}
//Color_Saturation
//0:-2
//1:-1
//2,0
//3,+1
//4,+2
void OV2640_Color_Saturation(uint8_t sat)
{
uint8_t reg7dval=((sat+2)<<4)|0X08;
SCCB_WR_Reg(0XFF,0X00);
SCCB_WR_Reg(0X7C,0X00);
SCCB_WR_Reg(0X7D,0X02);
SCCB_WR_Reg(0X7C,0X03);
SCCB_WR_Reg(0X7D,reg7dval);
SCCB_WR_Reg(0X7D,reg7dval);
}
//Brightness
//0:(0X00)-2
//1:(0X10)-1
//2,(0X20) 0
//3,(0X30)+1
//4,(0X40)+2
void OV2640_Brightness(uint8_t bright)
{
SCCB_WR_Reg(0xff, 0x00);
SCCB_WR_Reg(0x7c, 0x00);
SCCB_WR_Reg(0x7d, 0x04);
SCCB_WR_Reg(0x7c, 0x09);
SCCB_WR_Reg(0x7d, bright<<4);
SCCB_WR_Reg(0x7d, 0x00);
}
//Contrast
//0:-2
//1:-1
//2,0
//3,+1
//4,+2
void OV2640_Contrast(uint8_t contrast)
{
uint8_t reg7d0val=0X20;
uint8_t reg7d1val=0X20;
switch(contrast)
{
case 0://-2
reg7d0val=0X18;
reg7d1val=0X34;
break;
case 1://-1
reg7d0val=0X1C;
reg7d1val=0X2A;
break;
case 3://1
reg7d0val=0X24;
reg7d1val=0X16;
break;
case 4://2
reg7d0val=0X28;
reg7d1val=0X0C;
break;
}
SCCB_WR_Reg(0xff,0x00);
SCCB_WR_Reg(0x7c,0x00);
SCCB_WR_Reg(0x7d,0x04);
SCCB_WR_Reg(0x7c,0x07);
SCCB_WR_Reg(0x7d,0x20);
SCCB_WR_Reg(0x7d,reg7d0val);
SCCB_WR_Reg(0x7d,reg7d1val);
SCCB_WR_Reg(0x7d,0x06);
}
//Special_Effects
//0:normal
//1,negative
//2,black-white
//3,red
//4,green
//5,blue
//6,classic
void OV2640_Special_Effects(uint8_t eft)
{
uint8_t reg7d0val=0X00;
uint8_t reg7d1val=0X80;
uint8_t reg7d2val=0X80;
switch(eft)
{
case 1://negative
reg7d0val=0X40;
break;
case 2://black-white
reg7d0val=0X18;
break;
case 3://red
reg7d0val=0X18;
reg7d1val=0X40;
reg7d2val=0XC0;
break;
case 4://green
reg7d0val=0X18;
reg7d1val=0X40;
reg7d2val=0X40;
break;
case 5://blue
reg7d0val=0X18;
reg7d1val=0XA0;
reg7d2val=0X40;
break;
case 6://classic
reg7d0val=0X18;
reg7d1val=0X40;
reg7d2val=0XA6;
break;
}
SCCB_WR_Reg(0xff,0x00);
SCCB_WR_Reg(0x7c,0x00);
SCCB_WR_Reg(0x7d,reg7d0val);
SCCB_WR_Reg(0x7c,0x05);
SCCB_WR_Reg(0x7d,reg7d1val);
SCCB_WR_Reg(0x7d,reg7d2val);
}
//Color_Bar
//sw:0,close
// 1,open
void OV2640_Color_Bar(uint8_t sw)
{
uint8_t reg;
SCCB_WR_Reg(0XFF,0X01);
reg=SCCB_RD_Reg(0X12);
reg&=~(1<<1);
if(sw)reg|=1<<1;
SCCB_WR_Reg(0X12,reg);
}
void OV2640_Window_Set(uint16_t sx,uint16_t sy,uint16_t width,uint16_t height)
{
uint16_t endx;
uint16_t endy;
uint8_t temp;
endx=sx+width/2;
endy=sy+height/2;
SCCB_WR_Reg(0XFF,0X01);
temp=SCCB_RD_Reg(0X03);
temp&=0XF0;
temp|=((endy&0X03)<<2)|(sy&0X03);
SCCB_WR_Reg(0X03,temp);
SCCB_WR_Reg(0X19,sy>>2);
SCCB_WR_Reg(0X1A,endy>>2);
temp=SCCB_RD_Reg(0X32);
temp&=0XC0;
temp|=((endx&0X07)<<3)|(sx&0X07);
SCCB_WR_Reg(0X32,temp);
SCCB_WR_Reg(0X17,sx>>3);
SCCB_WR_Reg(0X18,endx>>3);
}
uint8_t OV2640_OutSize_Set(uint16_t width,uint16_t height)
{
uint16_t outh;
uint16_t outw;
uint8_t temp;
if(width%4)return 1;
if(height%4)return 2;
outw=width/4;
outh=height/4;
SCCB_WR_Reg(0XFF,0X00);
SCCB_WR_Reg(0XE0,0X04);
SCCB_WR_Reg(0X5A,outw&0XFF);
SCCB_WR_Reg(0X5B,outh&0XFF);
temp=(outw>>8)&0X03;
temp|=(outh>>6)&0X04;
SCCB_WR_Reg(0X5C,temp);
SCCB_WR_Reg(0XE0,0X00);
return 0;
}
uint8_t OV2640_ImageWin_Set(uint16_t offx,uint16_t offy,uint16_t width,uint16_t height)
{
uint16_t hsize;
uint16_t vsize;
uint8_t temp;
if(width%4)return 1;
if(height%4)return 2;
hsize=width/4;
vsize=height/4;
SCCB_WR_Reg(0XFF,0X00);
SCCB_WR_Reg(0XE0,0X04);
SCCB_WR_Reg(0X51,hsize&0XFF);
SCCB_WR_Reg(0X52,vsize&0XFF);
SCCB_WR_Reg(0X53,offx&0XFF);
SCCB_WR_Reg(0X54,offy&0XFF);
temp=(vsize>>1)&0X80;
temp|=(offy>>4)&0X70;
temp|=(hsize>>5)&0X08;
temp|=(offx>>8)&0X07;
SCCB_WR_Reg(0X55,temp);
SCCB_WR_Reg(0X57,(hsize>>2)&0X80);
SCCB_WR_Reg(0XE0,0X00);
return 0;
}
uint8_t OV2640_ImageSize_Set(uint16_t width,uint16_t height)
{
uint8_t temp;
SCCB_WR_Reg(0XFF,0X00);
SCCB_WR_Reg(0XE0,0X04);
SCCB_WR_Reg(0XC0,(width)>>3&0XFF);
SCCB_WR_Reg(0XC1,(height)>>3&0XFF);
temp=(width&0X07)<<3;
temp|=height&0X07;
temp|=(width>>4)&0X80;
SCCB_WR_Reg(0X8C,temp);
SCCB_WR_Reg(0XE0,0X00);
return 0;
}
以上代碼實作對OV2640的介面訪問, 實作OV2640初始化（配置為640×80 RGB模式），并持續向外輸出影像，
8. DMA發送機制
STM32通過串口接收指令，程式里設計一個標識變數scmd用于指示接收到的指令，需要在USB虛擬串口的接收函式里進行處理：
static int8_t CDC_Receive_FS(uint8_t* Buf, uint32_t *Len)
{
/* USER CODE BEGIN 6 */
extern uint8_t scmd;
if(Buf[0]==0x01) scmd=0x01;
USBD_CDC_SetRxBuffer(&hUsbDeviceFS, &Buf[0]);
USBD_CDC_ReceivePacket(&hUsbDeviceFS);
return (USBD_OK);
/* USER CODE END 6 */
}
以及在USART1的接收中斷里進行處理：
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
if (huart == &huart1)
{
if (aRxBuffer==0x01)
{
scmd = 0x02;
aRxBuffer=0x00;
HAL_UART_Receive_IT(&huart1, (uint8_t *)&aRxBuffer, 1);
}
else
{
HAL_UART_Receive_IT(&huart1, (uint8_t *)&aRxBuffer, 1);
}
}
return;
}
STM32向上位機發送影像資料采用USB虛擬串口或串口DMA方式，程式里設計一個標識變數tx_busy，在當前DMA發送完后指示狀態：
static int8_t CDC_TransmitCplt_FS(uint8_t *Buf, uint32_t *Len, uint8_t epnum)
{
uint8_t result = USBD_OK;
/* USER CODE BEGIN 13 */
extern uint8_t tx_busy ;
tx_busy = 0;
UNUSED(Buf);
UNUSED(Len);
UNUSED(epnum);
/* USER CODE END 13 */
return result;
}
同樣，對USART1的DMA發送完處理：
void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart)
{
extern uint8_t tx_busy;
if (huart == &huart1)
{
tx_busy = 0;
}
}
9. DCMI DMA地址自增方式
初始化DCMI DMA配置時，如將接收地址設定為不自增方式，后續的影像捕獲需要作業在DMA接收地址自增方式，因此單獨設計兩個函式可用于切換，
void DCMI_DMA_MemInc_En(void)
{
HAL_DMA_DeInit(&hdma_dcmi);
hdma_dcmi.Init.MemInc = DMA_MINC_ENABLE;
if (HAL_DMA_Init(&hdma_dcmi) != HAL_OK)
{
Error_Handler();
}
}
void DCMI_DMA_MemInc_Den(void)
{
HAL_DMA_DeInit(&hdma_dcmi);
hdma_dcmi.Init.MemInc = DMA_MINC_DISABLE;
if (HAL_DMA_Init(&hdma_dcmi) != HAL_OK)
{
Error_Handler();
}
}
10. 初始化修正函式
按照1.8版本HAL庫，設計DCMI的初始化修正函式：
void PY_DCMI_Full_Init(void)
{
hdcmi.Instance = DCMI;
hdcmi.Init.SynchroMode = DCMI_SYNCHRO_HARDWARE;
hdcmi.Init.PCKPolarity = DCMI_PCKPOLARITY_RISING;
hdcmi.Init.VSPolarity = DCMI_VSPOLARITY_HIGH;
hdcmi.Init.HSPolarity = DCMI_HSPOLARITY_LOW;
hdcmi.Init.CaptureRate = DCMI_CR_ALL_FRAME;
hdcmi.Init.ExtendedDataMode = DCMI_EXTEND_DATA_8B;
hdcmi.Init.JPEGMode = DCMI_JPEG_DISABLE;
hdcmi.Init.ByteSelectMode = DCMI_BSM_ALL;
hdcmi.Init.ByteSelectStart = DCMI_OEBS_ODD;
hdcmi.Init.LineSelectMode = DCMI_LSM_ALL;
hdcmi.Init.LineSelectStart = DCMI_OELS_ODD;
if (HAL_DCMI_Init(&hdcmi) != HAL_OK)
{
Error_Handler();
}
}
11. 主函式代碼
在程式跑起來后，會先對OV2640介面進行典型暫存器讀取并USART1串口輸出，用于識別介面時序是否正常，然后進入命令等待，接收到指令后，再從OV2640輸出的影像中截取資料串口DMA輸出，
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : main.c
* @brief : Main program body
******************************************************************************
* @attention
*
* <h2><center>© Copyright (c) 2021 STMicroelectronics.
* All rights reserved.</center></h2>
*
* This software component is licensed by ST under BSD 3-Clause license,
* the "License"; You may not use this file except in compliance with the
* License. You may obtain a copy of the License at:
* opensource.org/licenses/BSD-3-Clause
*
******************************************************************************
*/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "usb_device.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include <string.h>
#include "ov2640.h"
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
void DCMI_DMA_MemInc_En(void);
void DCMI_DMA_MemInc_Den(void);
void PY_OV2640_RGB565_CONFIG(void);
void PY_DCMI_Full_Init(void);
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
uint8_t aRxBuffer=0;
uint8_t TxBuff[99] = {0};
uint8_t StatusFlag = 0;
uint8_t ov2640_verh = 0xff, ov2640_verl=0xff;
HAL_StatusTypeDef dcmi_dma_status = HAL_OK;
uint32_t* dcmi_data_buff;
uint32_t DCMI_RN = 0; //row number
uint32_t DCMI_CN = 0; //column number
uint32_t DCMI_RS = 0; //row start
uint32_t DCMI_CS = 0; //column start
uint8_t scmd = 0;
uint8_t tx_busy = 0;
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
DCMI_HandleTypeDef hdcmi;
DMA_HandleTypeDef hdma_dcmi;
UART_HandleTypeDef huart1;
DMA_HandleTypeDef hdma_usart1_tx;
/* USER CODE BEGIN PV */
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_DMA_Init(void);
static void MX_DCMI_Init(void);
static void MX_USART1_UART_Init(void);
/* USER CODE BEGIN PFP */
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
int main(void)
{
/* USER CODE BEGIN 1 */
dcmi_data_buff = 0x30000000;
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_DMA_Init();
MX_USB_DEVICE_Init();
MX_DCMI_Init();
MX_USART1_UART_Init();
/* USER CODE BEGIN 2 */
if (HAL_UART_Receive_IT(&huart1, (uint8_t *)&aRxBuffer, 1)!=HAL_OK)
{
MX_USART1_UART_Init();
HAL_UART_Receive_IT(&huart1, (uint8_t *)&aRxBuffer, 1);
}
PY_OV2640_RGB565_CONFIG();
HAL_DCMI_DeInit(&hdcmi);
PY_DCMI_Full_Init();
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
if (scmd==1)
{
scmd = 0;
DCMI_DMA_MemInc_En();
HAL_DCMI_DisableCrop (&hdcmi);
TxBuff[0]=0x55;
TxBuff[1]=0xaa;
TxBuff[2]=0x02; //OV2640 Label
CDC_Transmit_FS(TxBuff, 3);
HAL_Delay(100);
dcmi_dma_status = HAL_DCMI_Init(&hdcmi);
for (uint8_t i=0; i<10;i++)
{
HAL_DCMI_DisableCrop (&hdcmi);
DCMI_RN = 48;
DCMI_CN = 1280;
DCMI_RS = 48*i;
DCMI_CS = 0;
HAL_DCMI_ConfigCrop (&hdcmi, DCMI_CS, DCMI_RS, DCMI_CN, DCMI_RN);
HAL_Delay(1);
HAL_DCMI_EnableCrop (&hdcmi);
HAL_Delay(1);
dcmi_dma_status = HAL_DCMI_Start_DMA(&hdcmi, DCMI_MODE_SNAPSHOT, dcmi_data_buff, DCMI_CN*DCMI_RN/4);
while(HAL_DMA_GetState(&hdcmi)==HAL_DMA_STATE_BUSY) ;
HAL_DCMI_Stop(&hdcmi);
tx_busy = 1;
CDC_Transmit_FS((uint8_t *)dcmi_data_buff, 61440);
while(tx_busy!=0) ;
}
}
if (scmd==2)
{
scmd = 0;
DCMI_DMA_MemInc_En();
HAL_DCMI_DisableCrop (&hdcmi);
TxBuff[0]=0x55;
TxBuff[1]=0xaa;
TxBuff[2]=0x02; //OV2640 Label
HAL_UART_Transmit(&huart1, TxBuff, 3, 0xFFFFFF);
HAL_Delay(100);
dcmi_dma_status = HAL_DCMI_Init(&hdcmi);
for (uint8_t i=0; i<10;i++)
{
HAL_DCMI_DisableCrop (&hdcmi);
DCMI_RN = 48;
DCMI_CN = 1280;
DCMI_RS = 48*i;
DCMI_CS = 0;
HAL_DCMI_ConfigCrop (&hdcmi, DCMI_CS, DCMI_RS, DCMI_CN, DCMI_RN);
HAL_Delay(1);
HAL_DCMI_EnableCrop (&hdcmi);
HAL_Delay(1);
dcmi_dma_status = HAL_DCMI_Start_DMA(&hdcmi, DCMI_MODE_SNAPSHOT, dcmi_data_buff, DCMI_CN*DCMI_RN/4);
while(HAL_DMA_GetState(&hdcmi)==HAL_DMA_STATE_BUSY) ;
HAL_DCMI_Stop(&hdcmi);
tx_busy = 1;
HAL_UART_Transmit_DMA(&huart1, (uint8_t *)dcmi_data_buff, 61440);
while(tx_busy!=0) ;
}
}
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
/** Supply configuration update enable
*/
HAL_PWREx_ConfigSupply(PWR_LDO_SUPPLY);
/** Configure the main internal regulator output voltage
*/
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE0);
while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}
/** Initializes the RCC Oscillators according to the specified parameters
* in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI48|RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState = RCC_HSI_DIV1;
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
RCC_OscInitStruct.HSI48State = RCC_HSI48_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
RCC_OscInitStruct.PLL.PLLM = 32;
RCC_OscInitStruct.PLL.PLLN = 480;
RCC_OscInitStruct.PLL.PLLP = 2;
RCC_OscInitStruct.PLL.PLLQ = 2;
RCC_OscInitStruct.PLL.PLLR = 2;
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_1;
RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOWIDE;
RCC_OscInitStruct.PLL.PLLFRACN = 0;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB buses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2
|RCC_CLOCKTYPE_D3PCLK1|RCC_CLOCKTYPE_D1PCLK1;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.SYSCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.AHBCLKDivider = RCC_HCLK_DIV2;
RCC_ClkInitStruct.APB3CLKDivider = RCC_APB3_DIV2;
RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV2;
RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV2;
RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV2;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
{
Error_Handler();
}
HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_HSI48, RCC_MCODIV_2);
}
/**
* @brief DCMI Initialization Function
* @param None
* @retval None
*/
static void MX_DCMI_Init(void)
{
/* USER CODE BEGIN DCMI_Init 0 */
/* USER CODE END DCMI_Init 0 */
/* USER CODE BEGIN DCMI_Init 1 */
/* USER CODE END DCMI_Init 1 */
hdcmi.Instance = DCMI;
hdcmi.Init.SynchroMode = DCMI_SYNCHRO_EMBEDDED;
hdcmi.Init.PCKPolarity = DCMI_PCKPOLARITY_RISING;
hdcmi.Init.CaptureRate = DCMI_CR_ALL_FRAME;
hdcmi.Init.ExtendedDataMode = DCMI_EXTEND_DATA_8B;
hdcmi.Init.SyncroCode.FrameEndCode = 0;
hdcmi.Init.SyncroCode.FrameStartCode = 0;
hdcmi.Init.SyncroCode.LineStartCode = 0;
hdcmi.Init.SyncroCode.LineEndCode = 0;
hdcmi.Init.JPEGMode = DCMI_JPEG_DISABLE;
hdcmi.Init.ByteSelectMode = DCMI_BSM_ALL;
hdcmi.Init.ByteSelectStart = DCMI_OEBS_ODD;
hdcmi.Init.LineSelectMode = DCMI_LSM_ALL;
hdcmi.Init.LineSelectStart = DCMI_OELS_ODD;
if (HAL_DCMI_Init(&hdcmi) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN DCMI_Init 2 */
/* USER CODE END DCMI_Init 2 */
}
/**
* @brief USART1 Initialization Function
* @param None
* @retval None
*/
static void MX_USART1_UART_Init(void)
{
/* USER CODE BEGIN USART1_Init 0 */
/* USER CODE END USART1_Init 0 */
/* USER CODE BEGIN USART1_Init 1 */
/* USER CODE END USART1_Init 1 */
huart1.Instance = USART1;
huart1.Init.BaudRate = 230400;
huart1.Init.WordLength = UART_WORDLENGTH_8B;
huart1.Init.StopBits = UART_STOPBITS_1;
huart1.Init.Parity = UART_PARITY_NONE;
huart1.Init.Mode = UART_MODE_TX_RX;
huart1.Init.HwFlowCtl = UART_HWCONTROL_NONE;
huart1.Init.OverSampling = UART_OVERSAMPLING_16;
huart1.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
huart1.Init.ClockPrescaler = UART_PRESCALER_DIV1;
huart1.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
if (HAL_UART_Init(&huart1) != HAL_OK)
{
Error_Handler();
}
if (HAL_UARTEx_SetTxFifoThreshold(&huart1, UART_TXFIFO_THRESHOLD_1_8) != HAL_OK)
{
Error_Handler();
}
if (HAL_UARTEx_SetRxFifoThreshold(&huart1, UART_RXFIFO_THRESHOLD_1_8) != HAL_OK)
{
Error_Handler();
}
if (HAL_UARTEx_DisableFifoMode(&huart1) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN USART1_Init 2 */
/* USER CODE END USART1_Init 2 */
}
/**
* Enable DMA controller clock
*/
static void MX_DMA_Init(void)
{
/* DMA controller clock enable */
__HAL_RCC_DMA1_CLK_ENABLE();
/* DMA interrupt init */
/* DMA1_Stream0_IRQn interrupt configuration */
HAL_NVIC_SetPriority(DMA1_Stream0_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(DMA1_Stream0_IRQn);
/* DMA1_Stream1_IRQn interrupt configuration */
HAL_NVIC_SetPriority(DMA1_Stream1_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(DMA1_Stream1_IRQn);
}
/**
* @brief GPIO Initialization Function
* @param None
* @retval None
*/
static void MX_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
/* GPIO Ports Clock Enable */
__HAL_RCC_GPIOA_CLK_ENABLE();
__HAL_RCC_GPIOE_CLK_ENABLE();
__HAL_RCC_GPIOD_CLK_ENABLE();
__HAL_RCC_GPIOC_CLK_ENABLE();
__HAL_RCC_GPIOB_CLK_ENABLE();
/*Configure GPIO pin Output Level */
HAL_GPIO_WritePin(GPIOE, GPIO_PIN_7|GPIO_PIN_8, GPIO_PIN_SET);
/*Configure GPIO pin Output Level */
HAL_GPIO_WritePin(GPIOD, GPIO_PIN_10, GPIO_PIN_SET);
/*Configure GPIO pin Output Level */
HAL_GPIO_WritePin(GPIOD, GPIO_PIN_11, GPIO_PIN_RESET);
/*Configure GPIO pins : PE7 PE8 */
GPIO_InitStruct.Pin = GPIO_PIN_7|GPIO_PIN_8;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
HAL_GPIO_Init(GPIOE, &GPIO_InitStruct);
/*Configure GPIO pins : PD10 PD11 */
GPIO_InitStruct.Pin = GPIO_PIN_10|GPIO_PIN_11;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);
/*Configure GPIO pin : PA8 */
GPIO_InitStruct.Pin = GPIO_PIN_8;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF0_MCO;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
}
/* USER CODE BEGIN 4 */
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
if (huart == &huart1)
{
if (aRxBuffer==0x01)
{
scmd = 0x02;
aRxBuffer=0x00;
HAL_UART_Receive_IT(&huart1, (uint8_t *)&aRxBuffer, 1);
}
else
{
HAL_UART_Receive_IT(&huart1, (uint8_t *)&aRxBuffer, 1);
}
}
return;
}
void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart)
{
if (huart == &huart1)
{
tx_busy = 0;
}
}
void DCMI_DMA_MemInc_En(void)
{
HAL_DMA_DeInit(&hdma_dcmi);
hdma_dcmi.Init.MemInc = DMA_MINC_ENABLE;
if (HAL_DMA_Init(&hdma_dcmi) != HAL_OK)
{
Error_Handler();
}
}
void DCMI_DMA_MemInc_Den(void)
{
HAL_DMA_DeInit(&hdma_dcmi);
hdma_dcmi.Init.MemInc = DMA_MINC_DISABLE;
if (HAL_DMA_Init(&hdma_dcmi) != HAL_OK)
{
Error_Handler();
}
}
void PY_OV2640_RGB565_CONFIG(void)
{
/*Camera Interface*/
SCCB_Rst(); //hard reset
HAL_Delay(100);
// SCCB_WR_Reg(0xff, 0x01); //soft reset
// SCCB_WR_Reg(0x12, 0x80);
// HAL_Delay(100);
ov2640_verh = SCCB_RD_Reg(0x1c);
HAL_Delay(50);
ov2640_verl = SCCB_RD_Reg(0x1d);
HAL_Delay(50);
while ((ov2640_verh==0xff)||(ov2640_verl==0xff))
{
HAL_UART_Transmit(&huart1, &ov2640_verh, 1, 0xFFFFFF);
HAL_Delay(500);
HAL_UART_Transmit(&huart1, &ov2640_verl, 1, 0xFFFFFF);
HAL_Delay(500);
}
OV2640_UXGA_Init();
//pix speed adjustment
SCCB_WR_Reg(0xff, 0x00);
SCCB_WR_Reg(0xd3, 0x00);
SCCB_WR_Reg(0XFF, 0X01);
SCCB_WR_Reg(0X11, 0x01);
OV2640_RGB565_Mode();
OV2640_OutSize_Set(640, 480);
HAL_Delay(200);
}
void PY_DCMI_Full_Init(void)
{
hdcmi.Instance = DCMI;
hdcmi.Init.SynchroMode = DCMI_SYNCHRO_HARDWARE;
hdcmi.Init.PCKPolarity = DCMI_PCKPOLARITY_RISING;
hdcmi.Init.VSPolarity = DCMI_VSPOLARITY_LOW;
hdcmi.Init.HSPolarity = DCMI_HSPOLARITY_LOW;
hdcmi.Init.CaptureRate = DCMI_CR_ALL_FRAME;
hdcmi.Init.ExtendedDataMode = DCMI_EXTEND_DATA_8B;
hdcmi.Init.JPEGMode = DCMI_JPEG_DISABLE;
hdcmi.Init.ByteSelectMode = DCMI_BSM_ALL;
hdcmi.Init.ByteSelectStart = DCMI_OEBS_ODD;
hdcmi.Init.LineSelectMode = DCMI_LSM_ALL;
hdcmi.Init.LineSelectStart = DCMI_OELS_ODD;
if (HAL_DCMI_Init(&hdcmi) != HAL_OK)
{
Error_Handler();
}
}
/* USER CODE END 4 */
/**
* @brief This function is executed in case of error occurrence.
* @retval None
*/
void Error_Handler(void)
{
/* USER CODE BEGIN Error_Handler_Debug */
/* User can add his own implementation to report the HAL error return state */
__disable_irq();
while (1)
{
}
/* USER CODE END Error_Handler_Debug */
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* @param file: pointer to the source file name
* @param line: assert_param error line source number
* @retval None
*/
void assert_failed(uint8_t *file, uint32_t line)
{
/* USER CODE BEGIN 6 */
/* User can add his own implementation to report the file name and line number,
ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
12. STM32H750完整代碼
基于STM32CUBEIDE工程：
https://download.csdn.net/download/hwytree/20387653
13. 上位機軟體
配套測驗用上位機軟體分為一維碼識別和二維碼識別兩個軟體，下載地址：
一維碼識別
https://download.csdn.net/download/hwytree/20306099
二維碼識別
https://download.csdn.net/download/hwytree/20306112
14. 一維碼識別效果
15. 二維碼識別效果
16. 上位機實作解碼原理范例
https://blog.csdn.net/hwytree/article/details/119004881
-End-
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標籤：其他