#include <pic16f1455.h>
#include "my_i2c_v4.h"

void IdleI2C( void ) //OKOK
{
	while ( ( SSP1CON2 & 0x1F ) | ( SSP1STATbits.R_nW ) )
	continue;
}

void OpenI2C( unsigned char sync_mode, unsigned char slew ) //
{
  /*
  SSP1STAT &= 0x3F;                // power on state
  SSP1CON1 = 0x00;                 // power on state
  SSP1CON2 = 0x00;                 // power on state
  SSP1CON1 |= sync_mode;           // select serial mode
  SSP1STAT |= slew;                // slew rate on/off
  */

  SSPSTAT = 0x80;       /* Slew rate disabled */
  SSPCON1 = 0x28;       /* Master mode        */
  SSPCON2 = 0x00;

  I2C_SCL = 1;               // Set SCL1 (PORTC,3) pin to input
  I2C_SDA = 1;               // Set SDA1 (PORTC,4) pin to input

  SSP1CON1 |= SSPENB;              // enable synchronous serial port
}

signed char getsI2C( unsigned char *rdptr, unsigned char length ) //OK
{
    while ( length-- )            // perform getcI2C1() for 'length' number of bytes
    {
      *rdptr++ = getcI2C();       // save byte received
      while ( SSP1CON2bits.RCEN ); // check that receive sequence is over

      if ( PIR2bits.BCL1IF )       // test for bus collision
      {
        return ( -1 );             // return with Bus Collision error
      }


	if( ((SSP1CON1&0x0F)==0x08) || ((SSP1CON1&0x0F)==0x0B) )	//master mode only
	{
      if ( length )               // test if 'length' bytes have been read
      {
        SSP1CON2bits.ACKDT = 0;    // set acknowledge bit state for ACK
        SSP1CON2bits.ACKEN = 1;    // initiate bus acknowledge sequence
        while ( SSP1CON2bits.ACKEN ); // wait until ACK sequence is over
      }
	}

    }
    return ( 0 );                  // last byte received so don't send ACK
}

unsigned char ReadI2C( void ) //OKOK
{
if( ((SSP1CON1&0x0F)==0x08) || ((SSP1CON1&0x0F)==0x0B) )	//master mode only
  SSP1CON2bits.RCEN = 1;           // enable master for 1 byte reception
  while ( !SSP1STATbits.BF );      // wait until byte received
  return ( SSP1BUF );              // return with read byte
}

signed char putsI2C( unsigned char *wrptr ) //OKOK
{
   unsigned char temp;
	while ( *wrptr )                 // transmit data until null character
  {
    if ( SSP1CON1bits.SSP1M3 )      // if Master transmitter then execute the following
    {
	  temp = putcI2C ( *wrptr );
	  if (temp ) return ( temp );
      //if ( putcI2C1( *wrptr ) )    // write 1 byte
      //{
      //  return ( -3 );             // return with write collision error
      //}
      //IdleI2C1();                  // test for idle condition
      //if ( SSP1CON2bits.ACKSTAT )  // test received ack bit state
      //{
      //  return ( -2 );             // bus device responded with  NOT ACK
      //}                            // terminate putsI2C1() function
    }

    else                           // else Slave transmitter
    {
      PIR1bits.SSP1IF = 0;         // reset SSP1IF bit
      SSP1BUF = *wrptr;            // load SSP1BUF with new data
      SSP1CON1bits.CKP = 1;        // release clock line
      while ( !PIR1bits.SSP1IF );  // wait until ninth clock pulse received

      if ( ( SSP1CON1bits.CKP ) && ( !SSP1STATbits.BF ) )// if R/W=0 and BF=0, NOT ACK was received
      {
        return ( -2 );             // terminate PutsI2C1() function
      }
    }

  wrptr ++;                        // increment pointer

  }                                // continue data writes until null character

  return ( 0 );
}

void NotAckI2C( void ) //OKOK
{
  SSP1CON2bits.ACKDT = 1;          // set acknowledge bit for not ACK
  SSP1CON2bits.ACKEN = 1;          // initiate bus acknowledge sequence
}

void CloseI2C( void ) //OKOK
{
  SSP1CON1 &= 0xDF;                 // disable synchronous serial port
}

signed char WriteI2C( unsigned char data_out ) //OKOK
{
  SSP1BUF = data_out;           // write single byte to SSP1BUF
  
  if (SSP1CON1bits.WCOL) {     // test if write collision occurred
    return ( -1 );              // if WCOL bit is set return negative #
  } else {
    
      if( ((SSP1CON1&0x0F)!=0x08) && ((SSP1CON1&0x0F)!=0x0B) )	{//slave mode only
	
        SSP1CON1bits.CKP = 1;        // release clock line
        while ( !PIR1bits.SSP1IF );  // wait until ninth clock pulse received
	  {
            if ( ( !SSP1STATbits.R_nW ) && ( !SSP1STATbits.BF ) ) {// if R/W=0 and BF=0, NOT ACK was received
                return ( -2 );             //Return NACK
            } else {
                return(0);				//Return ACK
            }
	  }

      } else if( ((SSP1CON1&0x0F)==0x08) || ((SSP1CON1&0x0F)==0x0B) ) {	//master mode only
	
            while( SSP1STATbits.BF );   // wait until write cycle is complete
            IdleI2C();                  // ensure module is idle
	    
            if ( SSP1CON2bits.ACKSTAT ) {// test for ACK condition received
	    	 return ( -2 );				//Return NACK
            } else {
                return ( 0 );               //Return ACK
            }
      }
  }

  return (0); //OVO SAM DODAO DA NE BACA WARNING

}

void StartI2C( void ) //OKOK
{
  SSP1CON2bits.SEN = 1;            // initiate bus start condition
}

void RestartI2C( void ) //OKOK
{
  SSP1CON2bits.RSEN = 1;           // initiate bus restart condition
}

void StopI2C( void )
{
  SSP1CON2bits.PEN = 1;            // initiate bus stop condition
}