Problem with temperature values in DS18B20 on PIC16F877

program Temp_DS1820

'Microcontroller: ATmega88 (Atmel AVR)
'Programming Language: BASIC
'Compiler: mikroBASIC PRO for AVR v2.10
'Sensor: DS18S20
'Programmer: Tahmid

dim LCD_RS as sbit at PORTB2_bit
dim LCD_EN as sbit at PORTB3_bit
dim LCD_D4 as sbit at PORTB4_bit
dim LCD_D5 as sbit at PORTB5_bit
dim LCD_D6 as sbit at PORTB6_bit
dim LCD_D7 as sbit at PORTB7_bit

dim LCD_RS_Direction as sbit at DDB2_bit
dim LCD_EN_Direction as sbit at DDB3_bit
dim LCD_D4_Direction as sbit at DDB4_bit
dim LCD_D5_Direction as sbit at DDB5_bit
dim LCD_D6_Direction as sbit at DDB6_bit
dim LCD_D7_Direction as sbit at DDB7_bit


sub procedure ConversionDelay()
    delay_ms(800)
end sub

sub procedure StabilizeDelay()
    delay_ms(200)
end sub

dim Temperature as word
dim TempH as byte
dim TempL as byte
dim TLow as byte
dim vDisp as string[9]
dim DecimalPoint as byte

main:
     DDRC = $FE 'RC0 input for One-Wire
     LCD_Init()
     LCD_Cmd(_LCD_CURSOR_OFF) 'LCD Cursor off
     LCD_Cmd(_LCD_CLEAR) 'Clear LCD
     StabilizeDelay() 'Wait for sensor and LCD to stabilize
     vDisp = "+124.5 'C"
     LCD_Out(1, 1, "Temp:")
     while true
         OW_Reset(PORTC, 0) 'Reset command to initialize One-Wire
         OW_Write(PORTC, 0, $CC) 'Skip ROM Command
         OW_Write(PORTC, 0, $44) 'Convert_T command
         ConversionDelay() 'Provide delay for conversion
         OW_Reset(PORTC, 0) 'Reset command to initialize One-Wire
         OW_Write(PORTC, 0, $CC) 'Skip ROM Command
         OW_Write(PORTC, 0, $BE) 'Read Scratchpad Command
         Temperature = OW_Read(PORTC, 0) 'Read Temperature low byte
         Temperature = Temperature + ((OW_Read(PORTC, 0)) << 8) 'Read Temperature high byte and convert low and high bytes to one 16-bit word
         TempH = Hi(Temperature) 'High 8 bits of Temperature
         TempL = Lo(Temperature) 'Low 8 bits of Temperature
         DecimalPoint = Temperature.B0 'Check if Temperature is integer or fractional
         if (Temperature and $8000) then 'If reading is negative
            vDisp[0] = "-"
            TempL = byte((not TempL + 1) >> 1)
         else 'If reading is positive
            vDisp[0] = "+"
            TempL = TempL >> 1 'Shift one position right (divide by 2) to get integer reading and get rid of decimal point
         end if
         vDisp[1] = TempL div 100 + 48 'Get hundreds and convert to ASCII
         vDisp[2] = (TempL div 10) mod 10 + 48 'Get tens and convert to ASCII
         vDisp[3] = TempL mod 10 + 48 'Get units and convert to ASCII
         if (DecimalPoint) then 'If reading is fractional, ie has 0.5 at end
            vDisp[5] = "5"
         else 'If reading is a whole number
            vDisp[5] = "0"
         end if
         LCD_Out(1, 8, vDisp) 'Show temperature
     wend
end.

// LCD module connections
sbit LCD_RS at RB4_bit;
sbit LCD_EN at RB5_bit;
sbit LCD_D4 at RB0_bit;
sbit LCD_D5 at RB1_bit;
sbit LCD_D6 at RB2_bit;
sbit LCD_D7 at RB3_bit;

sbit LCD_RS_Direction at TRISB4_bit;
sbit LCD_EN_Direction at TRISB5_bit;
sbit LCD_D4_Direction at TRISB0_bit;
sbit LCD_D5_Direction at TRISB1_bit;
sbit LCD_D6_Direction at TRISB2_bit;
sbit LCD_D7_Direction at TRISB3_bit;
// End LCD module connections

//  Set TEMP_RESOLUTION to the corresponding resolution of used DS18x20 sensor:
//  18S20: 9  (default setting; can be 9,10,11,or 12)
//  18B20: 12
const unsigned short TEMP_RESOLUTION = 12;

char *text = "000.0000";
unsigned temp;

void Display_Temperature(unsigned int temp2write) {
  const unsigned short RES_SHIFT = TEMP_RESOLUTION - 8;
  char temp_whole;
  unsigned int temp_fraction;

  // Check if temperature is negative
  if (temp2write & 0x8000) {
     LCD_Chr(2,4,'-');
     temp2write = ~temp2write + 1;
     }
  else{
     LCD_Chr(2,4,' ');
  }

  // Extract temp_whole
  temp_whole = temp2write >> RES_SHIFT ;

  // Convert temp_whole to characters
  if (temp_whole/100)
     text[0] = temp_whole/100  + 48;
  else
     text[0] = '0';

  text[1] = (temp_whole/10)%10 + 48;             // Extract tens digit
  text[2] =  temp_whole%10     + 48;             // Extract ones digit

  // Extract temp_fraction and convert it to unsigned int
  temp_fraction  = temp2write << (4-RES_SHIFT);
  temp_fraction &= 0x000F;
  temp_fraction *= 625;

  // Convert temp_fraction to characters
  text[4] =  temp_fraction/1000    + 48;         // Extract thousands digit
  text[5] = (temp_fraction/100)%10 + 48;         // Extract hundreds digit
  text[6] = (temp_fraction/10)%10  + 48;         // Extract tens digit
  text[7] =  temp_fraction%10      + 48;         // Extract ones digit

  // Print temperature on LCD
  Lcd_Out(2, 5, text);
}

void main() {
 ADCON1=0x06;

  Lcd_Init();                                    // Initialize LCD
  Lcd_Cmd(_LCD_CLEAR);                           // Clear LCD
  Lcd_Cmd(_LCD_CURSOR_OFF);                      // Turn cursor off
  Lcd_Out(1, 1, " Temperature:   ");
  // Print degree character, 'C' for Centigrades
  Lcd_Chr(2,13,223);                             // Different LCD displays have different char code for degree
                                                 // If you see greek alpha letter try typing 178 instead of 223

  Lcd_Chr(2,14,'C');

  //--- Main loop
  do {
    //--- Perform temperature reading
    Ow_Reset(&PORTE, 2);                         // Onewire reset signal
    Ow_Write(&PORTE, 2, 0xCC);                   // Issue command SKIP_ROM
    Ow_Write(&PORTE, 2, 0x44);                   // Issue command CONVERT_T
    Delay_us(120);

    Ow_Reset(&PORTE, 2);
    Ow_Write(&PORTE, 2, 0xCC);                   // Issue command SKIP_ROM
    Ow_Write(&PORTE, 2, 0xBE);                   // Issue command READ_SCRATCHPAD

    temp =  Ow_Read(&PORTE, 2);
    temp = (Ow_Read(&PORTE, 2) << 8) + temp;

    //--- Format and display result on Lcd
    Display_Temperature(temp);

    Delay_ms(500);
  } while (1);
}