Hello!

I'm a beginner with with pics, and need your help:
I searched over the web for a 1wire mcc18 lib, but I've found nothing complete...
I'd like to build a simple thermometer with 18f4520, ds1820 with 2  7 segmens display,
On a breadboard I've built it, the 7 segment display works well (connected on portD, and PortC) but
the ds1820 gives zero...

Thank you for your help!

here is the source: (the mcu is running @20MHz)
the main function isn't important, it must have to work, this is the new source which I've added to it...
I call from the main program with:

i = gettemp();
d1 = i/10;   //digit1
d2 = i%10; //digit2

What do you think? Where I made mistakes?

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#include <string.h>
#define MAX_SENSORS 1

// 1-wire prototypes
void _1w_init(int sensor);
int _1w_in_byte(int sensor);
void _1w_out_byte(int d, int sensor);
void _1w_pin_hi(int sensor);
void _1w_pin_low(int sensor);
void _1w_strong_pull_up(int sensor);	// not used in this routine

int gettemp(void)
{
   int buff[9], sensor, n;
   int temperature;
   sensor = 0;

      _1w_out_byte(0xcc, sensor);  // skip ROM

      _1w_out_byte(0x44, sensor);  // perform temperature conversion
      _1w_strong_pull_up(sensor);

      _1w_init(sensor);
      _1w_out_byte(0xcc, sensor);  // skip ROM

      _1w_out_byte(0xbe, sensor);  // read the result

      for (n=0; n<9; n++)
      {
         buff[n]=_1w_in_byte(sensor);
      }


	temperature = buff[0]>>1;  // temperature without LSB (0.5C)

  return temperature;
}

// The following are standard 1-Wire routines.
void _1w_init(int sensor)
{
   _1w_pin_hi(sensor);
   _1w_pin_low(sensor);
	  	  Delay10TCYx(250);

   _1w_pin_hi(sensor);
	  	  Delay10TCYx(250);
}

int _1w_in_byte(int sensor)
{
   int n, i_byte, temp, mask;
   mask = 0xff & (~(0x01<<sensor));
   for (n=0; n<8; n++)
   {
      PORTB=0x00;
      TRISB=mask;
      TRISB=0xff;

      temp=PORTB;
      if (temp & ~mask)
      {
        i_byte=(i_byte>>1) | 0x80;	// least sig bit first
      }
      else
      {
        i_byte=i_byte >> 1;
      }
	  	  Delay10TCYx(30);
   }
   return(i_byte);
}

void _1w_out_byte(int d, int sensor)
{
   int n, mask;
   mask = 0xff & (~(0x01<<sensor));
   for(n=0; n<8; n++)
   {
      if (d&0x01)
      {
         PORTB=0;
         TRISB=mask;		// momentary low
         TRISB=0xff;
	  	  Delay10TCYx(30);
      }

      else
      {
          PORTB=0;
          TRISB=mask;
	  	  Delay10TCYx(30);
          TRISB=0xff;
      }
      d=d>>1;
   }
}

void _1w_pin_hi(int sensor)
{
   TRISB = 0xff;
}

void _1w_pin_low(int sensor)
{
   PORTB = 0x00;
   TRISB = 0xff & (~(0x01 << sensor));
}

void _1w_strong_pull_up(int sensor)	// bring DQ to strong +5VDC
{
   PORTB = 0x01 << sensor;
   TRISB = 0xff & (~(0x01 << sensor));
   Delay1KTCYx(1250);
   TRISB = 0xff;
}




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