OV7670 + ARDUINO

OV7670_initalisation.ino

#define SIO_C 2
#define SIO_D 4
#define SIO_CLKDELAY 100


void setup (void)
{
 Serial.begin(9600);
 
 
 if(InitOV7670())
   Serial.println("Init OV7670 : OK");
 else
   Serial.println("Init OV7670 : NG....");
   
     
}


void loop( void)
{
  
  Serial.println("Writing test :");
  
  byte data = 0x84;
  Serial.println(data);
  
  if(WriteOV7670(0x12, data))  
    Serial.println("Writing : OK");
  else
    Serial.println("Writing : NG...");
    
  
  
  /*--------------------------*/
  
  
  Serial.println("\n Reading test :");
  
  char rdata = 0x20;
  char ip = 0x43;
  
    if(ReadOV7670(0x0A, &rdata, ip))  
    {
      Serial.println("Reading : OK ");    
    }
    else
      Serial.println("Reading : NG...");
      
    Serial.println(rdata, HEX);
    
    if(rdata == 0x76)
      Serial.println("youpi");
        
  /*-----------------------------*/
  int temp = 3600;
  delay(temp*1000);
  
}




void InitSCCB(void)
{
  pinMode(SIO_C, OUTPUT);
  pinMode(SIO_D, OUTPUT);
  digitalWrite(SIO_C, HIGH);
  digitalWrite(SIO_D, HIGH);
  Serial.println("InitSCCB - Port Direction and set high.");
}





void StartSCCB(void)
{
 Serial.println("Starting SCCB...");

 /*put HIGH in order to avoid propagating unknown bus state.*/
 digitalWrite(SIO_D, HIGH);
 delayMicroseconds(SIO_CLKDELAY);
 digitalWrite(SIO_C, HIGH);
 delayMicroseconds(SIO_CLKDELAY);
 digitalWrite(SIO_D, LOW);
 delayMicroseconds(SIO_CLKDELAY);
 digitalWrite(SIO_C, LOW);

  Serial.println("Starting SCCB : done."); 
}





void StopSCCB(void)
{
  Serial.println("Stoping SCCB...");
 
  digitalWrite(SIO_D,LOW);
  delayMicroseconds(SIO_CLKDELAY);
  digitalWrite(SIO_C,HIGH);
  delayMicroseconds(SIO_CLKDELAY);
  digitalWrite(SIO_D,HIGH);
  delayMicroseconds(SIO_CLKDELAY);

  Serial.println("Stoping SCCB : done.");  
}






char WriteSCCB( byte m_data)
{
 unsigned char j, tem;

 for(j=0;j<8;j++)
 {
   /*write the MSB not written yet :*/
   if((m_data<<j)&0x80)
   {
     digitalWrite(SIO_D, HIGH);
   }
   else
   {
     digitalWrite(SIO_D, LOW); 
   }
   
   delayMicroseconds(SIO_CLKDELAY);
   digitalWrite(SIO_C, HIGH);
   delayMicroseconds(SIO_CLKDELAY);
   digitalWrite(SIO_C, LOW);
   delayMicroseconds(SIO_CLKDELAY);
   
 } 
 
 /*eight bits have been send, let's deal with the ninth Don't-care one*/
 /*we put the SIO_D pin at low in order to avoid propagating any unknown state.*/
 /*why input ? because it enables a high impedance, I suppose...?*/
 pinMode(SIO_D, INPUT);
 digitalWrite(SIO_D, LOW);
 
 delayMicroseconds(SIO_CLKDELAY);
 digitalWrite(SIO_C, HIGH);
 delayMicroseconds(SIO_CLKDELAY); 
 
 /*there is something to read to check the transmission :*/
 if(digitalRead(SIO_D)==HIGH)
 {
  Serial.println("SCCB Write NG");
  tem = 0;
 }
 else
 {
   tem = 1;
  Serial.println("SCCB Write : OK."); 
 }
 
 digitalWrite(SIO_C, LOW);
 delayMicroseconds(SIO_CLKDELAY);
 
 /*let's clean that up :*/
 pinMode(SIO_D, OUTPUT);
 
 return tem;
}




char ReadSCCB( char* m_data)
{
 unsigned char j, tem = 1;
 /*we have to return tem but there is no way to assert that something/nothing happend apparently ?...*/


 /*Let's make things readable :*/
 //pinMode(SIO_D, INPUT);
 digitalWrite(SIO_D, LOW);
 /*Hi-Z*//*TEST*/
 
 
 for(j=0;j<8;j++)
 {      
   delayMicroseconds(SIO_CLKDELAY);
   digitalWrite(SIO_C, HIGH);
   
   
   /*let's read in the middle of the SIO_C cycle :*/
   /*read the MSB not read yet :*/
   if(digitalRead(SIO_D) != LOW)
   {
     *m_data = 0x01 | (*m_data << 1);
   }
   else
   {
     *m_data = 0xFE & (*m_data << 1) ;
   }
   
   delayMicroseconds(SIO_CLKDELAY);
   
   
   
   digitalWrite(SIO_C, LOW);
   delayMicroseconds(SIO_CLKDELAY);
   
 } 
 
 /*eight bits have been read, let's deal with the ninth Don't-care one*/
 /*the master is responsible for driver SIO_D at logical 1 during the NA bit.*/
 pinMode(SIO_D, OUTPUT);
 digitalWrite(SIO_D, HIGH);
 
 delayMicroseconds(SIO_CLKDELAY);
 digitalWrite(SIO_C, HIGH);
 delayMicroseconds(SIO_CLKDELAY); 
 
 /*there is something/nothing to read to check the transmission ???*/
 
 digitalWrite(SIO_C, LOW);
 delayMicroseconds(SIO_CLKDELAY);
 
 
 
 /*let's clean that up : reset as usual as if we had written...*/
 pinMode(SIO_D, OUTPUT);
 digitalWrite(SIO_D, LOW);
 
 return tem;
}



int WriteOV7670(char regID, char regData)
{
 StartSCCB();

 /*let's indicate that we want to write :*/
 if(WriteSCCB(0x42) == 0)
 {
  Serial.println("Problem : 3phase Write Error 0x42 phase 1.");
  StopSCCB();
  
  return(0);
 } 
 
 delayMicroseconds(SIO_CLKDELAY);
 
 /*phase 2 : sub address*/
 if(WriteSCCB(regID) == 0)
 {
   Serial.println("Problem : 3phase Write Error phase 2.");
   StopSCCB();

   return(0);   
 }
 
 delayMicroseconds(SIO_CLKDELAY);
 
 /*phase 3 : data writing*/
 if(WriteSCCB(regData) == 0)
 {
   Serial.println("Problem : 3phase Write Error phase 3.");
   StopSCCB();
   
   return(0);
 }
 
 /*exiting*/
 StopSCCB();
 
 return(1);
 
}




int ReadOV7670(char regID, char* regData, char ip)
{
 StartSCCB();

/*2-phase write transmission cycle */
/*---------------------------------*/

 /*let's indicate that we want to write :*/
 if(WriteSCCB(0x42) == 0)
 {
  Serial.println("Problem : 2phase Write Error 0x42 phase 1-1.");
  StopSCCB();
  
  return(0);
 } 
 
 delayMicroseconds(SIO_CLKDELAY);
 
 /*phase 2 : sub-address*/
 if(WriteSCCB(regID) == 0)
 {
   Serial.println("Problem : 2phase Write Error phase 1-2.");
   StopSCCB();

   return(0);   
 }
 
 delayMicroseconds(SIO_CLKDELAY);


/*---------------------------------*/

/*2-phase read transmission cycle*/
 /*phase 1 : ID address*/
 if(WriteSCCB(ip) == 0)/*test 0x21 instead of 0x43*/
 {
   Serial.println("Problem : 2phase Read Error phase 2-1.");
   StopSCCB();

   return(0);   
 }
 
 delayMicroseconds(SIO_CLKDELAY);


 /*phase 2 : data reading*/
 if(ReadSCCB(regData) == 0)
 {
   Serial.println("Problem : 2phase Read Error phase 2-2.");
   StopSCCB();
   
   return(0);
 }
 
 
 /*exiting*/
 StopSCCB();
 
 return(1);
 
}






int InitOV7670(void)
{
 char temp;
 int i = 0;
 
 InitSCCB();

 temp = 0x80;
 
 /*let's reset the SCCB ! */
 if( WriteOV7670( 0x12, temp) == 0)
 {
   Serial.println("Problem : Resetting SCCB NG.");
   return(0);
 }

 /*-------------*/ 
 /*settings : */
 
 
 /*-------------*/
 
 return(0x01);
}

In order to solve the "Problem: 2phase Read Error phase 2-1" you need to drive a clock signal to the XCLK of the camera module. I did it by fusing the CKOUT of my AVR.

hello
don't forget to uncomment line 181 to get good results
good luck

Hi I'm having a lot of difficulty getting the ov7670 working I've got to Problem : 2phase Read Error phase 2-1. How do I set the xclck fuse and how do I output the image please help

hello all, can you help me on OV7670 camera interface with Arduino?

This is working for me with a FIFO OV7670 on arduino uno connection the camera SIOC and SIOD to pin D2 and D4.

But now that this seems to work how do I get a picture? xD

can anyone provide connection diagram??

This is working for me with a FIFO OV7670 on arduino uno connection the camera SIOC and SIOD to pin D2 and D4.

But now that this seems to work how do I get a picture? xD

Hi:
Do you solve it?