// onewire library, for dallas onewire devices
// currently includes:
//   - generic onewire functions (init, readbyte, sendbyte, crc, etc.)
//   - ds1822 dallas-semi econo-thermometer

// (C) copyright 2003 j.d.sandoz / jds-pic !at! losdos.dyndns.org

// released under the GNU GENERAL PUBLIC LICENSE (GPL)
// refer to http://www.gnu.org/licenses/gpl.txt

// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA



//Previously Posted in CCS thread from jds-pic
//Revision Made By SCanan Date: 26.06.2007
#include <16f628.h>
#device *=16
// internal osilator used
#FUSES NOWDT,INTRC, NOPUT, NOPROTECT, NOBROWNOUT, NOMCLR, NOLVP, NOCPD//for 16f628
#use delay(clock=4000000)
#USE RS232(BAUD=9600, XMIT=PIN_B2, RCV=PIN_B1)


#include "1wire.c"

int8 tH,tL,Conf;

float ds1820_read()
{
int8 busy=0, temp1, temp2;
signed int16 temp3;
float result;

onewire_reset();
onewire_write(0xCC);
onewire_write(0x44);
delay_ms(200);
while (busy == 0)
  busy = onewire_read();

onewire_reset();
onewire_write(0xCC);
onewire_write(0xBE);
temp1 = onewire_read();
temp2 = onewire_read();
tH=onewire_read();
tL=onewire_read();
Conf=onewire_read();
temp3 = make16(temp2, temp1);

//result = (float) temp3 / 2.0;   // 0.5 deg C resolution
result = (float) temp3 / 16.0;  //0.1 deg C resolution
delay_ms(200);
return(result);
}
void main()
{
float temperature;

setup_timer_0(RTCC_INTERNAL|RTCC_DIV_1);
setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);

//for  10 bit resolution mod 
onewire_write(0xCC);
onewire_write(0x4E);

onewire_write(125);
  onewire_write(-55); //this should be done for proper working of DS18B20
   onewire_write(127);

onewire_reset();
   onewire_write(0xCC);
    onewire_write(0x48);
    delay_ms(15);



while (1)
{
  temperature = ds1820_read();

printf("Temperature= %3.1f\n\r",temperature);
}

}

////// 1wire.c fontion //////
///// DS18b20 data pin connected to  pic16f628 B0 pin //////



/***********************1Wire Class***********************/
/*Description: This class handles all communication */
/* between the processor and the 1wire */
/* sensors.
/*********************************************************/

/*-------1-wire definitions-------*/
#define ONE_WIRE_PIN PIN_B0

/*******************1-wire communication functions********************/


void onewire_reset()  // OK if just using a single permanently connected device
{
output_low(ONE_WIRE_PIN);
delay_us( 500 ); // pull 1-wire low for reset pulse
output_float(ONE_WIRE_PIN); // float 1-wire high
delay_us( 500 ); // wait-out remaining initialisation window.
output_float(ONE_WIRE_PIN);
}

/*********************** onewire_write() ********************************/
/*This function writes a byte to the sensor.*/
/* */
/*Parameters: byte - the byte to be written to the 1-wire */
/*Returns: */
/*********************************************************************/

void onewire_write(int data)
{
int count;

for (count=0; count<8; ++count)
{
  output_low(ONE_WIRE_PIN);
  delay_us( 2 ); // pull 1-wire low to initiate write time-slot.
  output_bit(ONE_WIRE_PIN, shift_right(&data,1,0)); // set output bit on 1-wire
  delay_us( 60 ); // wait until end of write slot.
  output_float(ONE_WIRE_PIN); // set 1-wire high again,
  delay_us( 2 ); // for more than 1us minimum.
}
}

/*********************** read1wire() *********************************/
/*This function reads the 8 -bit data via the 1-wire sensor. */
/* */
/*Parameters: */
/*Returns: 8-bit (1-byte) data from sensor */
/*********************************************************************/

int onewire_read()
{
int count, data;

for (count=0; count<8; ++count)
{
  output_low(ONE_WIRE_PIN);
  delay_us( 2 ); // pull 1-wire low to initiate read time-slot.
  output_float(ONE_WIRE_PIN); // now let 1-wire float high,
  delay_us( 8 ); // let device state stabilise,
  shift_right(&data,1,input(ONE_WIRE_PIN)); // and load result.
  delay_us( 120 ); // wait until end of read slot.
}

return( data );
}