Hi,
HAve this working code, but not completly, cause when temperature is negative it goes from -1,9 -3,0 - 3,1 ect. never -2,2 -2,3 ect.-

I also add 500 to the result, cause i then dont have to deal with any negative numbers, ect for storing in EEPROM ect.

 if(reset()==0)
            {
      
            write(Skip_ROM); 
            __delay_us(10);
            write(Convert_T);     
            __delay_ms(DS18B20_CONV_TIME);
            reset();
            write(Skip_ROM);
            __delay_us(10);
            write(Read_scratchpad); 
            //reset();

          
                lsb = read();
                msb = read();
              
                unsigned int sign = 248 & msb;
                if(sign==0)
                    decimal = lsb & 15;

                if(sign!=0)
                {
                    decimal = lsb ^ 15;
                    decimal = decimal^255;

                }

                unsigned char places[4]= {0};
                if((decimal&8) == 8)
                {

                    places[0] =  places[0] + 5;

                }

                if((decimal&4)==4)
                {
                    places[0] = places[0] + 2;
                    places[1] = places[1] + 5;
                }

                if((decimal&2)==2)
                {
                    places[0] = places[0] + 1;
                    places[1] = places[1] + 2;
                    places[2] = places[2] + 5;
                }

                if((decimal&1)==1)
                {
                    places[1] = places[1] + 6;
                    if(places[1]>9)
                    {
                        places[1]= places[1]-10;
                        places[0]= places[0]+1;
                    }

                    places[2] = places[2] + 2;
                    places[3] = places[3] + 5;

                }


                if(sign!=0)
                {
                    integer1 =(places[0]*1000);
                    integer2 = (places[1]*100);
                    integer3 = (places[2]*10);
                    integer4 = (places[3]);
                    integer = integer1+integer2+integer3+integer4;
                    if(integer==0)
                    {
                        sign_flag=1;
                    }
                    integer = 10000-integer;

                    integer1 = integer/1000;
                    integer2 = (integer/100)-(10*integer1);
                    integer3 = (integer/10)-(100*integer1)-(10*integer2);
                    places[0]= integer1;
                    places[1]= integer2;
                    places[2]= integer3;
                    places[3]= integer4;

                }
                lsb = lsb >> 3;
                msb = msb << 5;
                lsb = msb | lsb;
                if(sign !=0)
                {
                    lsb =(lsb)^255;
                    buffer[0]='-';
                }
                else
                    buffer[0] = '+';

                lsb = lsb >>1;
                printf("sign %d\n", sign_flag);

                buffer[1] = ((lsb / 100)%10) + 48;
                buffer[2] = (((lsb / 10)%10) + 48);
                buffer[3] = (((lsb)%10))+ 48 + sign_flag;
                buffer[4] = '.';
                buffer[5] = ((places[0]%10)+48);
                buffer[6] = ((places[1]%10)+48);
                buffer[7] = ((places[2]%10)+48);
                buffer[8] = ((places[3]%10)+48);
                buffer[9] = ' ' ;//0xF8;
                buffer[10]= 'C';
              
                total=0;
                total=((lsb / 100)%10)* 100;
                total=total+(((lsb / 10)%10) * 10);
                total=total+(((lsb)% 10))+  sign_flag;
                fraction=0;
                fraction=((places[0]%10)+48)-48;
                 if (sign!=0)
                      
                    {now=500-((total*10)+fraction); // add 50 degree du to no negativ result
                  
                 }
                     if (sign==0)
                      {
                         now=500+((total*10)+fraction); // add 50 degrees
                  
                }
    }

Hope it gives some meaning,
Code is C , for microchip made in MPLAB X.


This graph is done over 1 hour,

 

Have been testet some code i found online, Works fine, but when temperature reach 0 degrees, code will not work, when temperature is negative.

 if(reset()==0)
            {
        
            write(Skip_ROM);   
            __delay_us(10);
            write(Convert_T);       
            __delay_ms(DS18B20_CONV_TIME);
            reset();
            write(Skip_ROM);
            __delay_us(10);
            write(Read_scratchpad);   
            
     lsb = read();
     msb = read();
     TReading = (msb<< 8) + lsb;
     SignBit = TReading & 0x8000;  // test most sig bit
     if (SignBit) // negative
     {
         TReading = (TReading ^ 0xffff) + 1; // 2's comp
     }
     Tc_100 = (6 * TReading) + TReading / 4;    // multiply by (100 * 0.0625) or 6.25

     Whole = Tc_100 / 100;  // separate off the whole and fractional portions
     Fract = Tc_100 % 100;

     if (SignBit) // If its negative
     {
     // do things negativ    //  Use format  ex 5105  = 10,5 degree. 
// ex. 6525 = (6525-5000)= 1525 = 15,25 Degree.
//ex. 4750 = (5000-4750) = 250 = -2,50 Degree, with "-" in front,.
                now= 5000-((Whole*100)+Fract);  // Sets 5000 as my ZERO. degree, cause i then only need to handle positive numbers.
     }
     else
     { now=5000+((Whole*100)+Fract);  // if positive, i add 5000 

    
     } // end

Any hints, i am not good at using all that bitshifting ect. I just want a Whole Degree and a 1-2 digits DECIMAL.