ee.c

Microchi PIC Hi-Tech_C I2C_for_24LC01_and_Dalla_temperature

 ee_delay(); 
 SDA=0;                  	/* Stop condition */
 TRIS1=0;		 		 	/* SDA OUTPUT     */
 ee_delay();
 SCL = 1;
 ee_delay();
 SDA = 1;
 ee_delay();
 return(TRUE);
}
/******************************************************************************/
bit ReadTemperatureFromDS1775(byte *MSByteRead, byte *LSByteRead)
{
 if(!SetDataPointerDS1775(0))		/* Set the data pointer to Temperature */
  return(FALSE);
 /* Returns True if write was successfully acknowledged */
 ee_start();		 			/* Send start sequence */

 ee_byte(READ_CONTROL_BYTE);   	/* Control byte (READ) */ 

 if (ack()) 
  {
	ReadError=3;
	return(FALSE);
  }

 ee_data(MSByteRead);      		/* Get the data MSbyte */

 MasterAck();					/* Acknowledge the data received */

 ee_data(LSByteRead);      		/* Get the data LSbyte */

 ack();							/* Master NAck */

 SCL=0;                  		/* Stop condition */
 ee_delay();
 SDA=0;
 TRIS1=0;		 				/* SDA OUTPUT	    */
 ee_delay();
 SCL=1;
 ee_delay();
 SDA=1;
 return(TRUE);
}
/******************************************************************************/
bit SetDataPointerDS1775(byte NewDataPointer)
{
 /* Returns True if write was successfully acknowledged */
 ee_start();		 			/* Send start sequence */

 ee_byte(WRITE_CONTROL_BYTE);   /* Control byte (WRITE) */ 

 if (ack()) 
  {
	ReadError=1;
	return(FALSE); 		/* Test Acknowledge	*/
  }

 ee_byte(NewDataPointer);		/* Set Data Pointer to Config register */
 
 if (ack()) 
  {
	ReadError=2;
	return(FALSE); 		/* Test Acknowledge	*/
  }

 SCL=0;
 ee_delay(); 
 SDA=0;                  	/* Stop condition */
 TRIS1=0;		 		 	/* SDA OUTPUT     */
 ee_delay();
 SCL = 1;
 ee_delay();
 SDA = 1;
 ee_delay();
 return(TRUE);
}
/******************************************************************************/
void MasterAck(void)
{
 SCL=0;                 /* Acknowledge 		*/
 ee_delay();
 SDA=0;
 TRIS1=0;				/* SDA Output		*/
 ee_delay();
 SCL=1;
 ee_delay();			
 SCL=0;
}
/******************************************************************************/
/******************** I2C comms to the DS1721	*******************************/
bit ConfigByteDS1721(byte NewConfig)
{
 /* Returns True if write was successfully acknowledged */
 ee_start();		 			/* Send start sequence */

 ee_byte(WRITE_CONTROL_BYTE);   /* Control byte (WRITE) */ 

 if (ack())
  return(FALSE); 				/* Test Acknowledge	*/

 ee_byte(ACCESS_CONFIG);		/* Write Config Command */

 if (ack())
  return(FALSE); 				/* Test Acknowledge	*/

 ee_byte(NewConfig);			/* Write New configuration */

 if (ack())
  return(FALSE); 				/* Test Acknowledge	*/
 
 SCL=0;
 ee_delay(); 
 SDA=0;                  		/* Stop condition */
 TRIS1=0;		 		 		/* SDA OUTPUT     */
 ee_delay();
 SCL = 1;
 ee_delay();
 SDA = 1;
 ee_delay();
 return(TRUE);
}
/******************************************************************************/
bit StartTemperatureConversionDS1721(void)
{
 /* Returns True if write was successfully acknowledged */
 ee_start();		 			/* Send start sequence */

 ee_byte(WRITE_CONTROL_BYTE);   /* Control byte (WRITE) */ 

 if (ack())
  return(FALSE); 				/* Test Acknowledge	*/

 ee_byte(START_TEMP_CONVERT);	/* Write Start Temperature Conversion command */

 if (ack())
  return(FALSE); 				/* Test Acknowledge	*/

 SCL=0;
 ee_delay(); 
 SDA=0;                  		/* Stop condition */
 TRIS1=0;		 		 		/* SDA OUTPUT     */
 ee_delay();
 SCL = 1;
 ee_delay();
 SDA = 1;
 ee_delay();
 return(TRUE);
}
/******************************************************************************/
bit ReadTemperatureConversionStatusDS1721(byte *IsBusy)
{
  /* Returns True if write was successfully acknowledged */
 ee_start();		 			/* Send start sequence */

 ee_byte(WRITE_CONTROL_BYTE);   /* Control byte (WRITE) */ 

 if (ack())
  return(FALSE); 				/* Test Acknowledge	*/

 ee_byte(ACCESS_CONFIG);		/* Write Config Command */

 if (ack())
  return(FALSE); 				/* Test Acknowledge	*/

 ee_RepeatStart();				/* Restart Comms command to read */

 ee_byte(READ_CONTROL_BYTE);	/* Control byte (READ) */

 if (ack())
  return(FALSE); 				/* Test Acknowledge	*/

 ee_data(IsBusy);				/* Get the DS1721 status */

 ack();							/* Master NAck */

 SCL=0;                  		/* Stop condition */
 ee_delay();
 SDA=0;
 TRIS1=0;		 				/* SDA OUTPUT	    */
 ee_delay();
 SCL=1;
 ee_delay();
 SDA=1;
 return(TRUE);
}
/******************************************************************************/
void ee_RepeatStart(void)
{
 SCL = 0;
 ee_delay();
 TRIS &= 0b11111001;	 		/* make SCL and SDA outputs 	*/
 ee_delay();
 SDA = 1;
 ee_delay();
 SCL = 1;
 ee_delay();
 SDA = 0;						/* Restart now! */
}
/******************************************************************************/
bit IsDS1721Busy(void)
{unsigned char cRetries=0, Busy=0;
 
 while(cRetries < 254)
  {								/* Read the DS1721 status */
  	if(ReadTemperatureConversionStatusDS1721(&Busy))
     break;
     else
     cRetries++;
  }
 
 if(cRetries < 254)
  {
    if(Busy & 0x80)				/* Check if DS1721 is still busy */
     return(FALSE);				/* DS1721 is done */
     else
     return(TRUE);				/* DS1721 is still */
  }
  else
  return(TRUE);					/* There was an error reading the status */
}
/******************************************************************************/
bit ReadTemperatureFromDS1721(byte *MSByteRead, byte *LSByteRead)
{
 /* Returns True if write was successfully acknowledged */
 ee_start();		 			/* Send start sequence */

 ee_byte(WRITE_CONTROL_BYTE);   /* Control byte (WRITE) */ 

 if (ack())
  return(FALSE); 				/* Test Acknowledge	*/

 ee_byte(READ_TEMPERATURE);		/* Write READ_TEMPERATURE Command */

 if (ack())
  return(FALSE); 				/* Test Acknowledge	*/

 ee_RepeatStart();				/* Restart Comms command to read */

 ee_byte(READ_CONTROL_BYTE);	/* Control byte (READ) */

 if (ack())
  return(FALSE); 				/* Test Acknowledge	*/

 ee_data(MSByteRead);      		/* Get the data MSbyte */

 MasterAck();					/* Acknowledge the data received */

 ee_data(LSByteRead);      		/* Get the data LSbyte */

 ack();							/* Master NAck */

 SCL=0;                  		/* Stop condition */
 ee_delay();
 SDA=0;
 TRIS1=0;		 				/* SDA OUTPUT	    */
 ee_delay();
 SCL=1;
 ee_delay();
 SDA=1;
 return(TRUE);
}
/******************************************************************************/