#include <htc.h>
#include <pic16f628a.h>
#include <stdint.h>


#define SCL     TRISA4 // I2C bus
#define SDA     TRISA0 //
#define SCL_IN  PORTA,RA4    //
#define SDA_IN  PORTA,RA0    //
#define TMR0_2 (TMR0 & 1<<2)
#define LM75AD 0b10010000
__CONFIG (0x3D11);

   unsigned char mpx_cnt;
   unsigned char tempmsb;
   unsigned char templsb;
   unsigned char tempBCD1;
   unsigned char tempBCD2;
   

const int pat7seg2[10]=
{

	0b10000001,		//0
	0b11011101,		//1
	0b01000011,		//2
	0b01010001,		//3
	0b00011101,		//4
	0b10110000,		//5		
	0b00100001,		//6
	0b11010101,		//7
	0b00000001,		//8
	0b00010001,		//9
};

const int pat7seg3[10]=
{

	0b00000001,		//0
	0b00101111,		//1
	0b01000010,		//2
	0b00100010,		//3
	0b00101100,		//4
	0b00110000,		//5		
	0b00010000,		//6
	0b00101011,		//7
	0b00000000,		//8
	0b00100000,		//9
};

const int pat7seg4[10]=
{

	0b10000001,		//0
	0b10101111,		//1
	0b11000010,		//2
	0b10100010,		//3
	0b10101100,		//4
	0b10110000,		//5		
	0b10010000,		//6
	0b10101011,		//7
	0b10000000,		//8
	0b10100000,		//9
};



void Wait()
{
   unsigned char i;
   for(i=0;i<100;i++)
      _delay(10000);
}

void i2c_dly(void)
{
		_delay(20);
}

void i2c_start(void)
{
  SDA = 1;             // i2c start bit sequence
  i2c_dly();
  SCL = 1;
  i2c_dly();
  SDA = 0;
  i2c_dly();
  SCL = 0;
  i2c_dly();
}

void i2c_stop(void)
{
  SDA = 0;             // i2c stop bit sequence
  i2c_dly();
  SCL = 1;
  i2c_dly();
  SDA = 1;
  i2c_dly();
}

unsigned char i2c_rx(char ack)
{
unsigned char x, d=0;
  SDA = 1; 
  for(x=0; x<8; x++) {
    d <<= 1;
    do {
      SCL = 1;

    }
    while(SCL_IN==0);    // wait for any SCL clock stretching
    i2c_dly();
    if(SDA_IN) d |= 1;
    SCL = 0;
  } 
  if(ack) SDA = 0;
  else SDA = 1;
  SCL = 1;
  i2c_dly();             // send (N)ACK bit
  SCL = 0;
  SDA = 1;
  return (d) ;

}

bit i2c_tx(unsigned char d)
{
char x;
static bit b;
  for(x=8; x; x--) {
    if(d&0x80) SDA = 1;
    else SDA = 0;
    SCL = 1;
	i2c_dly();
    d <<= 1;
    SCL = 0;
	i2c_dly();
  }
  SDA = 1;
  i2c_dly();
  SCL = 1;
  i2c_dly();
  
  b = SDA_IN;          // possible ACK bit
  SCL = 0;
  return b;
}




void ReadI2C()
{
	SDA = SCL = 1;
	SCL_IN = SDA_IN = 0;

i2c_start();              // send start sequence
i2c_tx(0xE0);             // SRF08 I2C address with R/W bit clear
i2c_tx(0x00);             // SRF08 command register address
i2c_tx(0x51);             // command to start ranging in cm
i2c_stop();               // send stop sequence




}

void main()
{

   OPTION_REG = 0b11010111;
   //Initialize PORTD
   //PD0 as Output
CMCON=0B00000111;
TRISA=0B11111111;
PORTB=0b11111111;
PORTA=0b11100000;
   tempmsb=0;
   templsb=0;
	
  
   while(1)
   {

				TRISA=0B11111111;
				PORTB=0b11111111;
				PORTA=0b11100000;

				i2c_dly;	
				
				


				//Set Pointer to the Temperature Register
				i2c_start();
				i2c_tx(0b10010000);				
				i2c_tx(0b00000000);
								
						

			

				//Eead temperature sensor

				i2c_start();
				i2c_tx(0b10010001);
				tempmsb=i2c_rx(1);				
				templsb=i2c_rx(0);
				i2c_stop();
				tempmsb=tempmsb-6;	
				tempBCD1=tempmsb/10;
				tempBCD2=tempmsb % 10;
				TRISA=0B11111111;
   				TRISB=0B11111111;	
				




			for(mpx_cnt=0;mpx_cnt < 1000000/2048/4; mpx_cnt++)
				{
					TRISA=0B11111111;
   					TRISB=0B00000000;
					while(!TMR0_2)
					;
					
					PORTB=pat7seg4[tempBCD1];					
					TRISA=0B11110111;
					PORTA=0B11110111;

					while(TMR0_2)
					;

					while(!TMR0_2)
					;
					TRISA=0B11111111;
					PORTB=pat7seg3[tempBCD2];
					TRISA=0B11111011;
					PORTA=0B11111011;
					while(TMR0_2)
					;

					while(!TMR0_2)
					;
					TRISA=0B11111111;
					if((templsb & 0B10000000)) 
					{
					PORTB=pat7seg2[5];
					}
 					else
					{
 					PORTB=pat7seg2[0] ;
					}
					TRISA=0B11111101;
					PORTA=0B11111101;
					while(TMR0_2)
					;

					while(!TMR0_2)
					;
					TRISA=0B11111111;
					PORTB=0B00100011;
					
					TRISA=0B11111110;
					PORTA=0B11111110;
					while(TMR0_2)
					;


				}

  }	

}