LinkSprite JPEG Color Camera TTL - error with hexadecimal numbers

hi there,

i have serial camera connected arduino using following code:

code: [select]

byte incomingbyte;
int a=0x0000,j=0,k=0,count=0;                    //read starting address      
uint8_t mh,ml;
boolean endflag=0;
                              
void sendresetcmd();
void sendtakephotocmd();
void sendreaddatacmd();
void stoptakephotocmd();

void setup()
{
 serial.begin(38400);
 serial1.begin(38400);
}

void loop()
{
    sendresetcmd();
    delay(4000);                               //after reset, wait 2-3 second send take picture command
    
     sendtakephotocmd();

    while(serial1.available()>0)
     {
       incomingbyte=serial1.read();

     }  
     byte a[32];
    
     while(!endflag)
     {  
        j=0;
        k=0;
        count=0;
        sendreaddatacmd();

        delay(25);
         while(serial1.available()>0)
         {
              incomingbyte=serial1.read();
              k++;
              if((k>5)&&(j<32)&&(!endflag))
              {
              a[j]=incomingbyte;
              if((a[j-1]==0xff)&&(a[j]==0xd9))      //check if picture over
              endflag=1;                          
              j++;
      count++;
              }
         }
        
         for(j=0;j<count;j++)
         {   if(a[j]<0x10)
             serial.print("0");
             serial.print(a[j],hex);
             serial.print(" ");
         }                                       //send jpeg picture on serial port
         serial.println();
     }      
    while(1);
}

//send reset command
void sendresetcmd()
{
     serial1.write(0x56);
     serial1.write(0x00);
     serial1.write(0x26);
     serial1.write(0x00);
}

//send take picture command
void sendtakephotocmd()
{
     serial1.write(0x56);
     serial1.write(0x00);
     serial1.write(0x36);
     serial1.write(0x01);
     serial1.write(0x00);
}

//read data
void sendreaddatacmd()
{
     mh=a/0x100;
     ml=a%0x100;
     serial1.write(0x56);
     serial1.write(0x00);
     serial1.write(0x32);
     serial1.write(0x0c);
     serial1.write(0x00);
     serial1.write(0x0a);
     serial1.write(0x00);
     serial1.write(0x00);
     serial1.write(mh);
     serial1.write(ml) ;  
     serial1.write(0x00);
     serial1.write(0x00);
     serial1.write(0x00);
     serial1.write(0x20);
     serial1.write(0x00);
     serial1.write(0x0a);
     a+=0x20;                          
}

void stoptakephotocmd()
{
     serial1.write(0x56);
     serial1.write(0x00);
     serial1.write(0x36);
     serial1.write(0x01);
     serial1.write(0x03);      
}

by using code hexadecimal numbers. problem can't convert these hexadecimal numbers jpeg file. what's pretty weird jpeg file starts "ff d8", there no "ff d8" in data. there mistake?

i don't understand question. .jpg file format has defined structure specific , required header information, , part of may looking at.

however, should understand hexadecimal 1 way of representing binary number.

this line prints out binary data in hexadecimal representation:

code: [select]

serial.print(a[j],hex);

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