ov7670 正点原子摄像头 V2.2版 sccb读取是0xff ？？？

hpdell

现在在捣鼓这个ov7670 v2.2 带fifo的摄像头，目前通过sccb进行读写测试时，写摄像头有应答，可以； 但是读出来的数据全部是0xff,

SCCB->SCL   外部已经加了上4.7K拉电阻
SCCB->SDA   外部已经加了上4.7K拉电阻
程序如下：

#define SCCB_ID   0X42   //OV7670的ID

#define SCCB_SEND_ACK (0x10)

#define SCCB_SEND_NACK (0x11)  

#define SCCB_STATE_NACK (0x20)

#define SCCB_STATE_ACK  (0x21)

#define SCCB_SCL  GPIOEout(2)        // 定义 I2C-SCL 为 GPIOE_Pin_2

#define SCCB_SDA  GPIOEout(3)        // 定义 I2C-SDA 为 GPIOE_Pin_3

#define SCCB_SCL_L   (SCCB_SCL=0)    //#define I2C1_SCL_L         GPIOB->BSRRL = GPIO_Pin_6

#define SCCB_SCL_H   (SCCB_SCL=1)    //#define I2C1_SCL_H         GPIOB->BSRRH = GPIO_Pin_6

#define SCCB_SDA_L   (SCCB_SDA=0)    //#define I2C1_SDA_L         GPIOB->BSRRL = GPIO_Pin_7

#define SCCB_SDA_H   (SCCB_SDA=1)    //#define I2C1_SDA_H         GPIOB->BSRRH = GPIO_Pin_7

   

 

#define SCCB_SDA_IN()  GPIOEin(3)

#define SCCB_SDA_OUT() GPIOEout(3)  

 

 

#define SCCB_SDA_READ      ((GPIOE->IDR)  & GPIO_Pin_3)

void SCCB_Delay(u16 i)

{        

   while(i--); 

}

#define SCCB_Delay_5us     SCCB_Delay(8)

#define SCCB_Delay_3us     SCCB_Delay(6)

#define SCCB_Delay_2us     SCCB_Delay(4)

#define SCCB_Delay_1us     SCCB_Delay(2)

void SCCB_Init(void)

{

GPIO_InitTypeDef GPIO_InitStructure;

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE,ENABLE);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2 | GPIO_Pin_3; //SCCB  SCL->E2, SDA->E3

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;

GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;

GPIO_Init(GPIOE, &GPIO_InitStructure);

SCCB_SCL_H;

SCCB_Delay_5us;

SCCB_Delay_5us;

SCCB_SDA_H;

SCCB_Delay_5us;    

    

}

/**********************************************************

启动子程序

在 SCL 高电平期间 SDA 发生负跳变【从高到低】

scl为高电平期间,sda产生一个下降沿

 **********************************************************/

u8 SCCB_Start(void)

{

  u8 i;

SCCB_SDA_H;

  SCCB_SCL_H;

SCCB_Delay_5us;

  

i=0;

while((SCCB_SDA_READ == 1) && (i<250)) //如果SCCB_SDA=1,表示被控器无应答或损坏

{

i++; //计时开始，

if(i==249) //如果计时到了249，器件还没有应答则自动退出

return (SCCB_STATE_NACK);

}

      

  

SCCB_SDA_L;

  SCCB_Delay_5us;

i=0;

while((SCCB_SDA_READ == 1) && (i<250)) //如果SCCB_SDA=1,表示被控器无应答或损坏

{

i++; //计时开始，

if(i==249) //如果计时到了249，器件还没有应答则自动退出

return (SCCB_STATE_NACK);

}

 

  

  SCCB_SCL_L;

  SCCB_Delay_2us;

  

  return SCCB_STATE_ACK; //SUCCESS;

}

/**********************************************************

停止子函数

在 SCL 高电平期间 SDA 发生正跳变 【从低到高】

scl高电平期间,sda产生一上升沿

 **********************************************************/

void SCCB_Stop(void)

{

  SCCB_SDA_L;

  SCCB_Delay_1us;

SCCB_SCL_H;

SCCB_Delay_5us;

SCCB_SDA_H;

  SCCB_Delay_3us;

}

/**********************************************************

//读一字节 ack: SCCB_SEND_ACK 时应答，SCCB_SEND_NACK 时不应答

 **********************************************************/

u8 SCCB_ReadByte(unsigned char ack) //【非常好】

{

u8 i = 0,Read_Data=0;

  SCCB_SDA_H;

  SCCB_SDA_IN(); //设置SDA为输入  

for(i=0;i<8;i++)          // 循环移入8个位

{

    

SCCB_Delay_1us;          //5us

    SCCB_SCL_L;

    SCCB_Delay_5us;

    SCCB_SCL_H;

SCCB_Delay_5us;

    Read_Data <<= 1;

    

if(SCCB_SDA_READ)        //读SDA

{

      Read_Data++;

}

}

  SCCB_SCL_L;

  SCCB_Delay_3us;      //5us

  SCCB_SDA_OUT(); //设置SDA为输出    

SCCB_Delay_3us;      //5us

  if(ack == SCCB_SEND_ACK)

 SCCB_SDA_L;       //发送应答

  else

    SCCB_SDA_H;       //发送非应答

  

  SCCB_Delay_2us;      //5us

SCCB_SCL_H;

  SCCB_Delay_5us;

  SCCB_SCL_L;

  SCCB_Delay_1us;      //5us

return (Read_Data);

}

/**********************************************************

//向总线写一字节,并返回有无应答

 **********************************************************/

unsigned char SCCB_WriteByte(unsigned char write_data)

{

  unsigned char i;

  for(i=0;i<8;i++)

  {

    if(write_data & 0x80)

     SCCB_SDA_H;

    else

     SCCB_SDA_L; 

    

    SCCB_Delay_1us;

    SCCB_SCL_H;     //置时钟线为高，通知被控器开始接收数据位 

    SCCB_Delay_5us;

    SCCB_SCL_L;

    write_data <<= 1;

     

  }

SCCB_SDA_IN(); //设置SDA为输入

  SCCB_Delay_2us;

  SCCB_SDA_H;

  SCCB_Delay_2us;

  SCCB_SCL_H;

  SCCB_Delay_3us;

  

i=0;

while((SCCB_SDA_READ == 1) && (i<250)) //如果SCCB_SDA=1,表示被控器无应答或损坏

{

i++; //计时开始，

if(i==249) //如果计时到了249，器件还没有应答则自动退出

return (SCCB_STATE_NACK);

}

SCCB_SCL_L;

SCCB_Delay_2us;

SCCB_SDA_OUT(); //设置SDA为输出  

return (SCCB_STATE_ACK);  

}

//写寄存器

//返回值:SCCB_STATE_ACK->成功; SCCB_STATE_NACK->失败.

u8 SCCB_WR_Reg(u8 reg,u8 data)

{

u8 res = SCCB_STATE_NACK;

SCCB_Start(); //启动SCCB传输

res=SCCB_WriteByte(SCCB_ID); //写器件ID

if(SCCB_STATE_NACK == res)

res=1;  

if(SCCB_STATE_NACK == SCCB_WriteByte(reg))

res=1; 

 

if(SCCB_STATE_NACK == SCCB_WriteByte(data))

res=1;

 

SCCB_Stop();  

  return res;

}

//读寄存器

//返回值:读到的寄存器值

u8 SCCB_RD_Reg(u8 reg)

{

u8 val=0;

SCCB_Start(); //启动SCCB传输

printexp(USART1, "DCMI_id",SCCB_WriteByte(SCCB_ID),16) ; //写器件ID  

  //SCCB_WriteByte(reg); //写寄存器地址  

 printexp(USART1, "DCMI_reg",SCCB_WriteByte(reg),16) ;

SCCB_Stop();   

SCCB_Delay_5us;

 

//设置寄存器地址后，才是读

SCCB_Start();

//SCCB_WriteByte(SCCB_ID|0X01); //发送读命令  

printexp(USART1, "SCCB_ID|0X01",SCCB_WriteByte(SCCB_ID|0X01),16) ;

  val=SCCB_ReadByte(SCCB_SEND_NACK); //读取数据

  SCCB_Stop();

printexp(USART1, "SCCB_val",val,16) ;

  return val;

}

//初始化成功返回0，否则返回1

u8 Cam_Init(void)

{

u8 temp;

u16 i=0;

GPIO_InitTypeDef GPIO_InitStructure;

DCMI_InitTypeDef DCMI_InitStructure;

//DMA_InitTypeDef  DMA_InitStructure;

RCC_AHB2PeriphClockCmd(RCC_AHB2Periph_DCMI, ENABLE); //DCMI 

//RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE); //DMA2

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA | RCC_AHB1Periph_GPIOB | 

RCC_AHB1Periph_GPIOC | RCC_AHB1Periph_GPIOE, ENABLE);//使能DCMI的GPIO时钟

GPIO_PinAFConfig(GPIOC, GPIO_PinSource6, GPIO_AF_DCMI); //DCMI D0

GPIO_PinAFConfig(GPIOC, GPIO_PinSource7, GPIO_AF_DCMI); //DCMI D1

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(GPIOB, GPIO_PinSource6, GPIO_AF_DCMI); //DCMI D5

GPIO_PinAFConfig(GPIOE, GPIO_PinSource5, GPIO_AF_DCMI); //DCMI D6

GPIO_PinAFConfig(GPIOE, GPIO_PinSource6, GPIO_AF_DCMI); //DCMI D7

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;

GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_NOPULL;

GPIO_Init(GPIOC, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_4 | GPIO_Pin_5 | GPIO_Pin_6;

GPIO_Init(GPIOE, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;

GPIO_Init(GPIOB, &GPIO_InitStructure);

//---------------------------------------控制信号引脚定义---------------------------------------

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2 | GPIO_Pin_3 | GPIO_Pin_4| GPIO_Pin_6| GPIO_Pin_8; //DCMI 2->WRST, 3->RRST, 4->WEN, 6->RCLK, 8->OE(CS)

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;

GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;

//SYSCFG->CMPCR = 0x00000001; //使用IO 补偿单元，

//当GPIO 速度超过50M 的时候要考虑使用此设置

GPIO_Init(GPIOA, &GPIO_InitStructure);

//--------------VSYNC IN ---------------------------------

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7; //DCMI VSYNC

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN; //同步信号检测IO

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;

//GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;

//SYSCFG->CMPCR = 0x00000001;

GPIO_Init(GPIOB, &GPIO_InitStructure);

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);

/*

  DMA_DeInit(DMA2_Stream1);

  DMA_InitStructure.DMA_Channel = DMA_Channel_1;

  DMA_InitStructure.DMA_PeripheralBaseAddr = DCMI_DR_ADDRESS;

  DMA_InitStructure.DMA_Memory0BaseAddr = FSMC_LCD_ADDRESS;

  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;

  DMA_InitStructure.DMA_BufferSize = 1;

  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;

  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Disable;

  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;

  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;

  DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;

  DMA_InitStructure.DMA_Priority = DMA_Priority_High;

  DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Enable;

  DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full;

  DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;

  DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;  

  DMA_Init(DMA2_Stream1, &DMA_InitStructure);

*/

  SCCB_Init();         //初始化SCCB 的IO口   

temp = SCCB_WR_Reg(0x12,0x80);

  if(SCCB_STATE_NACK == temp) 

return 1; //复位SCCB  

delay_ms(50); 

//读取产品型号

  temp=SCCB_RD_Reg(0x0b);                               //就是这里，通过SCcB读取时，数据总是0xff，不知道河谷？？？？

printexp(USART1, "DCMI_0X0B",temp,16) ;    //读取的数据发回给电脑查看

if(temp!=0x73) 

return 2;  

  temp=SCCB_RD_Reg(0x0a);   

if(temp!=0x76) 

return 2;

//初始化序列  

for(i=0;i<sizeof(ov7670_init_reg_tbl)/sizeof(ov7670_init_reg_tbl[0])/2;i++)

{

SCCB_WR_Reg(ov7670_init_reg_tbl[0],ov7670_init_reg_tbl[1]);

delay_ms(2);

  }

return 0x00; //OK

}

正点原子

不是SCCB有问题吧？是DCIM方式读取有问题吧？
我们的摄像头经过了AL422B FIFO芯片，不能用摄像头控制器直接去读了。

hpdell

回复【2楼】正点原子:
---------------------------------
原来如此啊，

Shanel

hpdell 发表于 2013-5-13 15:08
回复【2楼】正点原子:
---------------------------------
原来如此啊，

你解决了吗？？我也出现这个问题，初始化老是无法成功，temp值始终为255

xiao55555

正点原子 发表于 2013-5-13 11:09
不是SCCB有问题吧？是DCIM方式读取有问题吧？
我们的摄像头经过了AL422B&nbsp;FIFO芯片，不能用摄像头控制 ...

你好，今天我用V2.2摄像头模块，返回图像数据一直是0xff，，，，

1354046363

顶，我的也是