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//PIN 18 -> RC3 -> SCL
//PIN 23 -> RC4 ->SDA

#include "i2c.h"
#include "conf.h"

void I2C_Master_Init(const unsigned long freq_K) //Begin IIC as master
{
  TRISC3 = 1;  TRISC4 = 1;  //Set SDA and SCL pins as input pins
  
  SSPCON  = 0b00101000;    //pg84/234 
  SSPCON2 = 0b00000000;    //pg85/234
  
  SSPADD = (_XTAL_FREQ/(4*freq_K*100))-1; //Setting Clock Speed pg99/234
  SSPSTAT = 0b00000000;    //pg83/234
}

void I2C_Master_Wait()
{
    while (   (SSPCON2 & 0b00011111)    ||    (SSPSTAT & 0b00000100)   ) ; //check the bis on registers to make sure the IIC is not in progress
}

void I2C_Master_Start()
{
  I2C_Master_Wait();  //Hold the program if I2C is busy  
  SEN = 1;     //Begin IIC pg85/234
}

void I2C_Master_Repeated_Start()
{
    I2C_Master_Wait();
    RSEN = 1;         //Initiate repeated start condition
}

void I2C_Master_Stop()
{
  I2C_Master_Wait(); //Hold the program is I2C is busy  
  PEN = 1;    //End IIC pg85/234
}

void I2C_Master_Write(unsigned data)
{
  I2C_Master_Wait(); //Hold the program is I2C is busy 
  SSPBUF = data;         //pg82/234
}

unsigned short I2C_Master_Read(unsigned short ack)
{
  unsigned short incoming;
  I2C_Master_Wait();
  RCEN = 1;
  
  I2C_Master_Wait();
  incoming = SSPBUF;      //get the data saved in SSPBUF
  
  I2C_Master_Wait();
  ACKDT = (ack)?0:1;    //check if ack bit received  
  ACKEN = 1;          //pg 85/234
  
  return incoming;
}