[SOLVED] PIC18F4550 RTC interfacing

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sbit LCD_RS at RD0_bit;
sbit LCD_EN at RD1_bit;
sbit LCD_D4 at RD4_bit;
sbit LCD_D5 at RD5_bit;
sbit LCD_D6 at RD6_bit;
sbit LCD_D7 at RD7_bit;
 
sbit LCD_RS_Direction at TRISD0_bit;
sbit LCD_EN_Direction at TRISD1_bit;
sbit LCD_D4_Direction at TRISD4_bit;
sbit LCD_D5_Direction at TRISD5_bit;
sbit LCD_D6_Direction at TRISD6_bit;
sbit LCD_D7_Direction at TRISD7_bit;
 
 
 
 
unsigned short read_ds1307(unsigned short address)
{
  unsigned short r_data;
  I2C1_Start();
 
  I2C1_Wr(0xD0); //address 0x68 followed by direction bit (0 for write, 1 for read) 0x68 followed by 0 --> 0xD0
  I2C1_Wr(address);
  I2C1_Repeated_Start();
  I2C1_Wr(0xD1); //0x68 followed by 1 --> 0xD1
  r_data=I2C1_Rd(0);
  I2C1_Stop();
  return(r_data);
}
 
 
void write_ds1307(unsigned short address,unsigned short w_data)
{
  I2C1_Start(); // issue I2C start signal
  //address 0x68 followed by direction bit (0 for write, 1 for read) 0x68 followed by 0 --> 0xD0
  I2C1_Wr(0xD0); // send byte via I2C (device address + W)
  I2C1_Wr(address); // send byte (address of DS1307 location)
  I2C1_Wr(w_data); // send data (data to be written)
  I2C1_Stop(); // issue I2C stop signal
}
 
 
unsigned char BCD2UpperCh(unsigned char bcd)
{
  return ((bcd >> 4) + '0');
}
 
 
unsigned char BCD2LowerCh(unsigned char bcd)
{
  return ((bcd & 0x0F) + '0');
}
 
 
int Binary2BCD(int a)
{
   int t1, t2;
   t1 = a%10;
   t1 = t1 & 0x0F;
   a = a/10;
   t2 = a%10;
   t2 = 0x0F & t2;
   t2 = t2 << 4;
   t2 = 0xF0 & t2;
   t1 = t1 | t2;
   return t1;
}
 
 
int BCD2Binary(int a)
{
   int r,t;
   t = a & 0x0F;
   r = t;
   a = 0xF0 & a;
   t = a >> 4;
   t = 0x0F & t;
   r = t*10 + r;
   return r;
}
 
 
 
int second;
int minute ;
int hour ;
int hr;
int ap;
 
char time[] = "00:00:00 PM";
short set;
 
void main()
{
    LCD_INIT();
    INTCON = 0x88;
    ADCON1.PCFG3 = 1; //as digital
    ADCON1.PCFG2 = 1; //as digital
    ADCON1.PCFG1 = 1; //as digital
    ADCON1.PCFG0 = 1; //as digital
    //INTCON2.RBPU = 1; //I tried enabling the internal pullups but it ddnt work
    TRISB = 0x0F;
   /*TRISB.RB4 = 1;
    TRISB.RB5 = 1;
    TRISB.RB6 = 1;
    TRISB.RB7 = 1;*/
    PORTB = 0;
    i2c1_init(100000);
 
    LCD_CMD(_lcd_CLEAR);
    LCD_CMD(_LCD_CURSOR_OFF);
    lcd_out(1,1,"TEST");
    set = 1;               //this value acts as the increment on setting time
    
   //DO THE WRITING ON RTC
    hour = BCD2Binary(hour);
    hour = hour + set;     //here is the increment
    hour = Binary2BCD(hour);
    if((hour & 0x1F) >= 0x13)
    {
      hour = hour & 0b11100001;
      hour = hour ^ 0x20;
    }
    else if((hour & 0x1F) <= 0x00)
    {
      hour = hour | 0b00010010;
      hour = hour ^ 0x20;
    }
    write_ds1307(2, hour); //write hour
    
    minute = BCD2Binary(minute);
    minute = minute + set; //also here is the increment
    if(minute >= 60)
       minute = 0;
    if(minute < 0)
       minute = 59;
    minute = Binary2BCD(minute);
    write_ds1307(1, minute); //write minute
    write_ds1307(2,0x00); // Write second
    
    //END WRITING ON RTC
 
    while(1)
    {
      //DO THE READING FROM RTC
      second = read_ds1307(0);
      minute = read_ds1307(1);
      hour = read_ds1307(2);
      hr = hour & 0b00011111;
      ap = hour & 0b00100000;
 
 
      time[0] = BCD2UpperCh(hr);
      time[1] = BCD2LowerCh(hr);
      time[3] = BCD2UpperCh(minute);
      time[4] = BCD2LowerCh(minute);
      time[6] = BCD2UpperCh(second);
      time[7] = BCD2LowerCh(second);
      
      LCD_OUT(2,1,time);
 
        
        
    }
 
}