花了幾天時間用stm32和ov7670搞了個圖像采集,這比我預想的要難很多。ov7670一百多個寄存器而且ov公司的datasheet簡陋得常常讓我想說一句:我去年買了個表。后來還是借鑒了網絡上的一些寄存器配置,在加上苦讀ov推出的資料終于還是搞出了個簡陋的摸樣出來。 話不多說了,給大家分享一下心得體會,以便幫助后面學習的朋友少走些彎路。
一:攝像頭不比其他的傳感器,有一定的難度,而且資料太過簡陋,后面學習的朋友盡量買些成熟產品做開發,比如說淘寶買的開發套件。我就吃了這虧,stm32和攝像頭完全從零做起,啥都沒有,連上位機都準備自己寫,這沒必要時間成本太高了。 二:不要指望自己一個一個寄存器去配置,本來資料就簡陋,有很多寄存器你看了資料未必能明白啥個意思,在網上找個配置方案(也可以借用我的配置方案)修改一些關鍵地方就行了。 三:注意焦距的調節,如果焦距調節不正確,可能畫面模糊一片,慢慢調節一下焦距圖像畫面應該就出來了(前提是你已經采集到了圖像) 四:注意SCCB(也就是I2C)的時序,可以借鑒我的初始化,但配置完成后用串口讀取一些寄存器的值打印出來,看是否配置成功,如果這個都沒有配置成功,你先別浪費時間找圖像了。 五:網上能下載到的上位機,一般都會顯示255的灰度圖像,而ov7670是不能夠輸出灰度圖像的,所以只能將輸出格式配置成為YUV,然后人為去掉UV,將Y傳給上位機顯示就是灰度圖像了。(注意網上下載的上位機軟件可能會有一些協議,最好先弄清楚,要不然你顯示肯定是顯示不出來的) 六:分辨率配置 (具體配置參考代碼)主要有一下幾個寄存器 0x 17 HSTART 0x 18 HSTOP 0x 19 VSTRT 0x 1A VSTOP 0x 03 VREF HREF 的高電平寬度等于我們所要顯示的一行 HREF = WEIGHT*2; 乘以二是因為每個像素點是有兩個 HSTOP=START + HREF; 184 + 320*2 = 824; 然后在用824對784求余就是HSTOP的值(其原因,請仔細度ov7670的時序,如果懶得看,直接用就行) 七:配置為YUV格式關鍵寄存器配置:(引用于網絡論壇,感謝他的分享) {0x12, 0x10},//QVGA YUV
{0x3a, 0x14},//使用固定UV輸出
{0x3d, 0x80},//使用固定UV輸出
{0x67, 0x11},//固定U值,0x11,方便測試
{0x68, 0xFF},//固定V值,0xFF,方便測試
{0x40, 0xC0},//初始配置,YUV模式,這個寄存器必須設置,否則不好使
為方便調試,都是用固定的U值和V值,
向67中寫入11,向68中寫入FF,出來的是XX11XXFF,說明配置成功。
要注意的就是{0x40, 0xC0},這個必須設置成初始化值,默認配置便是YUV,不能再用RGB565的配置。順便說一句,YUV模式為YUV 4:2:2,不是說8位里面4位Y,2位U,2位V的意思, Y/U/V都是8位數據,只是U和V是隔著Y輪流輸出的,高字節的是Y,低字節為U或V,做飛思卡爾智能車一般用的OV7620就是這樣,一般只用Y的數據,用來判斷黑白。 八:我的程序說明,各引腳(懶得打字,請看圖片吧),串口用的是STM32的UART3,還有需要注意的是我是用一個外部按鍵作為一幀圖片的發送,每按一次發送幀的圖片信號,用的是PA3。
寄存器配置 - void set_Cmos7670reg(void)
- {
- WrCmos7670(0x67,0xaa);
- WrCmos7670(0x68,0x55);
-
- WrCmos7670(0x3a,0x14);
- WrCmos7670(0x40,0xC0);
- WrCmos7670(0x12,0x10);
-
- WrCmos7670(0x32,0x80);
- WrCmos7670(0x17,0x16);
- WrCmos7670(0x18,0x04);
- WrCmos7670(0x19,0x02);
- WrCmos7670(0x1a,0x7b);
- WrCmos7670(0x03,0x06);
- WrCmos7670(0x0c,0x00);
- WrCmos7670(0x3e,0x00);
- WrCmos7670(0x70,0x3a);
- WrCmos7670(0x71,0x35);
- WrCmos7670(0x72,0x11);
- WrCmos7670(0x73,0x00);
- WrCmos7670(0xa2,0x02);
- WrCmos7670(0x11,0x81);
-
- WrCmos7670(0x7a,0x20);
- WrCmos7670(0x7b,0x1c);
- WrCmos7670(0x7c,0x28);
- WrCmos7670(0x7d,0x3c);
- WrCmos7670(0x7e,0x55);
- WrCmos7670(0x7f,0x68);
- WrCmos7670(0x80,0x76);
- WrCmos7670(0x81,0x80);
- WrCmos7670(0x82,0x88);
- WrCmos7670(0x83,0x8f);
- WrCmos7670(0x84,0x96);
- WrCmos7670(0x85,0xa3);
- WrCmos7670(0x86,0xaf);
- WrCmos7670(0x87,0xc4);
- WrCmos7670(0x88,0xd7);
- WrCmos7670(0x89,0xe8);
-
- WrCmos7670(0x13,0xe0);
- WrCmos7670(0x00,0x00);
-
- WrCmos7670(0x10,0x00);
- WrCmos7670(0x0d,0x00);
- WrCmos7670(0x14,0x28);
- WrCmos7670(0xa5,0x05);
- WrCmos7670(0xab,0x07);
- WrCmos7670(0x24,0x75);
- WrCmos7670(0x25,0x63);
- WrCmos7670(0x26,0xA5);
- WrCmos7670(0x9f,0x78);
- WrCmos7670(0xa0,0x68);
- WrCmos7670(0xa1,0x03);
- WrCmos7670(0xa6,0xdf);
- WrCmos7670(0xa7,0xdf);
- WrCmos7670(0xa8,0xf0);
- WrCmos7670(0xa9,0x90);
- WrCmos7670(0xaa,0x94);
- WrCmos7670(0x13,0xe5);
- WrCmos7670(0x0e,0x61);
- WrCmos7670(0x0f,0x4b);
- WrCmos7670(0x16,0x02);
- WrCmos7670(0x1e,0x37);
- WrCmos7670(0x21,0x02);
- WrCmos7670(0x22,0x91);
- WrCmos7670(0x29,0x07);
- WrCmos7670(0x33,0x0b);
- WrCmos7670(0x35,0x0b);
- WrCmos7670(0x37,0x1d);
- WrCmos7670(0x38,0x71);
- WrCmos7670(0x39,0x2a);
- WrCmos7670(0x3c,0x78);
- WrCmos7670(0x4d,0x40);
- WrCmos7670(0x4e,0x20);
- WrCmos7670(0x69,0x00);
- WrCmos7670(0x6b,0x60);
- WrCmos7670(0x74,0x19);
- WrCmos7670(0x8d,0x4f);
- WrCmos7670(0x8e,0x00);
- WrCmos7670(0x8f,0x00);
- WrCmos7670(0x90,0x00);
- WrCmos7670(0x91,0x00);
- WrCmos7670(0x92,0x00);
- WrCmos7670(0x96,0x00);
- WrCmos7670(0x9a,0x80);
- WrCmos7670(0xb0,0x84);
- WrCmos7670(0xb1,0x0c);
- WrCmos7670(0xb2,0x0e);
- WrCmos7670(0xb3,0x82);
- WrCmos7670(0xb8,0x0a);
- WrCmos7670(0x43,0x14);
- WrCmos7670(0x44,0xf0);
- WrCmos7670(0x45,0x34);
- WrCmos7670(0x46,0x58);
- WrCmos7670(0x47,0x28);
- WrCmos7670(0x48,0x3a);
- WrCmos7670(0x59,0x88);
- WrCmos7670(0x5a,0x88);
- WrCmos7670(0x5b,0x44);
- WrCmos7670(0x5c,0x67);
- WrCmos7670(0x5d,0x49);
- WrCmos7670(0x5e,0x0e);
- WrCmos7670(0x64,0x04);
- WrCmos7670(0x65,0x20);
- WrCmos7670(0x66, 0x05);
- WrCmos7670(0x94,0x04);
- WrCmos7670(0x95,0x08);
- WrCmos7670(0x6c,0x0a);
- WrCmos7670(0x6d,0x55);
- WrCmos7670(0x6e,0x11);
- WrCmos7670(0x6f,0x9f);
- WrCmos7670(0x6a,0x40);
- WrCmos7670(0x01,0x40);
- WrCmos7670(0x02,0x40);
- WrCmos7670(0x13,0xe7);
- WrCmos7670(0x15,0x00);
-
-
- WrCmos7670(0x4f,0x80);
- WrCmos7670(0x50,0x80);
- WrCmos7670(0x51,0x00);
- WrCmos7670(0x52,0x22);
- WrCmos7670(0x53,0x5e);
- WrCmos7670(0x54,0x80);
- WrCmos7670(0x58,0x9e);
-
- WrCmos7670(0x41,0x08);
- WrCmos7670(0x3f, 0x00);
- WrCmos7670(0x75,0x05);
- WrCmos7670(0x76,0xe1);
- WrCmos7670(0x4c,0x00);
- WrCmos7670(0x77,0x01);
- WrCmos7670(0x3d,0x80);
- WrCmos7670(0x4b,0x09);
- WrCmos7670(0xc9,0x60);
- WrCmos7670(0x41,0x38);
- WrCmos7670(0x56,0x40);
-
- WrCmos7670(0x34, 0x11);
- WrCmos7670(0x3b,0x02);
-
- WrCmos7670(0xa4,0x89);
- WrCmos7670(0x96,0x00);
- WrCmos7670(0x97,0x30);
- WrCmos7670(0x98,0x20);
- WrCmos7670(0x99,0x30);
- WrCmos7670(0x9a,0x84);
- WrCmos7670(0x9b,0x29);
- WrCmos7670(0x9c,0x03);
- WrCmos7670(0x9d, 0x4c);
- WrCmos7670(0x9e,0x3f);
- WrCmos7670(0x78,0x04);
-
- WrCmos7670(0x79,0x01);
- WrCmos7670(0xc8,0xf0);
- WrCmos7670(0x79,0x0f);
- WrCmos7670(0xc8,0x00);
- WrCmos7670(0x79,0x10);
- WrCmos7670(0xc8,0x7e);
- WrCmos7670(0x79,0x0a);
- WrCmos7670(0xc8, 0x80);
- WrCmos7670(0x79,0x0b);
- WrCmos7670(0xc8,0x01);
- WrCmos7670(0x79,0x0c);
- WrCmos7670(0xc8,0x0f);
- WrCmos7670(0x79,0x0d);
- WrCmos7670(0xc8,0x20);
- WrCmos7670(0x79,0x09);
- WrCmos7670(0xc8,0x80);
- WrCmos7670(0x79,0x02);
- WrCmos7670(0xc8,0xc0);
- WrCmos7670(0x79,0x03);
- WrCmos7670(0xc8,0x40);
- WrCmos7670(0x79,0x05);
- WrCmos7670(0xc8,0x30);
- WrCmos7670(0x79,0x26);
- WrCmos7670(0x09,0x00);
- }
- 圖片采集發送
- void EXTI1_IRQHandler(void)
- {
- u16 i,j,k=0;
- u8 t1,t2;
-
- EXTI_InitTypeDef EXTI_InitStructure;
- NVIC_InitTypeDefNVIC_InitStructure;
-
- EXTI_ClearITPendingBit(EXTI_Line1);
-
- Vsync_Flag++;
-
- if(Vsync_Flag==1) //FIFOD
- {
- GPIO_SetBits(GPIOE,GPIO_Pin_5); //FIFO_WRST=1;
- __asm{nop;}
- GPIO_ResetBits(GPIOE,GPIO_Pin_5); //FIFO_WRST=0;
-
- delay_us(2);
- GPIO_SetBits(GPIOE,GPIO_Pin_5); //FIFO_WRST=1;
- GPIO_SetBits(GPIOE,GPIO_Pin_3);
- }
-
- if(Vsync_Flag==2)
- {
- GPIO_ResetBits(GPIOE,GPIO_Pin_3); //FIFO_WR=0; //½ûÖ¹Êý¾ÝдÈëFIFO
-
- EXTI->IMR&=~(1<<4); //¹Ø±ÕÍⲿÖжÏ
- EXTI->EMR&=~(1<<4);
-
- EXTI_InitStructure.EXTI_Line= EXTI_Line1;
- EXTI_InitStructure.EXTI_Mode= EXTI_Mode_Interrupt;
- EXTI_InitStructure.EXTI_Trigger= EXTI_Trigger_Falling;
- EXTI_InitStructure.EXTI_LineCmd= DISABLE;
- EXTI_Init(&EXTI_InitStructure); //
-
- NVIC_InitStructure.NVIC_IRQChannel= TIM2_IRQn;
- NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority= 0;
- NVIC_InitStructure.NVIC_IRQChannelSubPriority= 0;
- NVIC_InitStructure.NVIC_IRQChannelCmd= DISABLE;
- NVIC_Init(&NVIC_InitStructure); //
- GPIO_SetBits(GPIOE,GPIO_Pin_4); //FIFO_RCK=1;
-
- GPIO_ResetBits(GPIOE,GPIO_Pin_6); //FIFO_RRST=0; //¶ÁÖ¸Õ븴λ
- GPIO_ResetBits(GPIOE,GPIO_Pin_4); //FIFO_RCK=0;
- __asm{nop;}__asm{nop;}
- GPIO_SetBits(GPIOE,GPIO_Pin_4); //FIFO_RCK=1;
- __asm{nop;}__asm{nop;}
-
- GPIO_ResetBits(GPIOE,GPIO_Pin_4); //FIFO_RCK=0;
-
- GPIO_SetBits(GPIOE, GPIO_Pin_6); //FIFO_RRST=1;
- __asm{nop;}
- delay_us(2);
- GPIO_ResetBits(GPIOE,GPIO_Pin_2); //FIFO_OE=0;//
- __asm{nop;}
-
- USART3_Putc(0xff); //請注意:這里是發送協議信號,不是圖像信號
-
- for(i = 0; i< 9600; i++)
- {
- for(j = 0; j < 8; j ++)
- {
- GPIO_ResetBits(GPIOE,GPIO_Pin_4);//FIFO_RCK=0;
- __asm{nop;}
-
- GPIO_SetBits(GPIOE,GPIO_Pin_4); //FIFO_RCK=1;
- __asm{nop;}
-
- t1=(0x00ff&GPIOC->IDR);
-
- GPIO_ResetBits(GPIOE,GPIO_Pin_4);//FIFO_RCK=0;
- __asm{nop;}
-
- GPIO_SetBits(GPIOE,GPIO_Pin_4); //FIFO_RCK=1;
- __asm{nop;}
-
- t2=(0x00ff&GPIOC->IDR);
- USART3_Putc(t1);
- }
- k=0; //
- }
-
- GPIO_SetBits(GPIOE,GPIO_Pin_2); //FIFO_OE=1;
-
- Vsync_Flag=0;
- NVIC_InitStructure.NVIC_IRQChannel= TIM2_IRQn;
- NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority= 0;
- NVIC_InitStructure.NVIC_IRQChannelSubPriority= 0;
- NVIC_InitStructure.NVIC_IRQChannelCmd= ENABLE;
- NVIC_Init(&NVIC_InitStructure);
-
- EXTI->IMR|=(1<<4);
- EXTI->EMR|=(1<<4);
- }
- }
復制代碼
最后上圖才有真相,電路雖然丑點但是可以用的。
1.002.jpg (60.92 KB, 下載次數: 133)
下載附件
2017-5-15 21:45 上傳
1.001.jpg (14.49 KB, 下載次數: 52)
下載附件
2017-5-15 21:45 上傳
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