7 segment clock/thermometer

/*
B number order

     --3--
  2 |     | 4
    |--1--|
  8 |     | 6
     --7--o = 5

*/
float temperature = 0, kelvin = 0;
int sensorPin = 0;
#include "Wire.h"
#define DS1307_ADDRESS 0x68
byte zero = 0x00; //workaround for issue #527
const byte symbols[3] = {
  B00000000, B10000000, B11110000
};

const byte ledCharSet[10] =
{
  B01110111, B00010100, B10110011, B10110110, B11010100,
  B11100110, B11100111, B00110100, B11110111, B11110110
};
const byte ledCharSetDot[10] =
{
  B01111111, B00011100, B10111011, B10111110, B11011100,
  B11101110, B11101111, B00111100, B11111111, B11111110
};

const int latchPin = 8;
const int clockPin = 12;
const int dataPin = 11;

void setup() {
   Wire.begin();
  setDateTime(); //MUST CONFIGURE IN FUNCTION
  pinMode(latchPin, OUTPUT);
  pinMode(clockPin, OUTPUT);
  pinMode(dataPin, OUTPUT);
  pinMode(sensorPin, INPUT);
  pinMode(10, OUTPUT);

}

void loop() {
      Wire.beginTransmission(DS1307_ADDRESS);
  Wire.write(zero);
  Wire.endTransmission();
  Wire.requestFrom(DS1307_ADDRESS, 7);
  int second = bcdToDec(Wire.read());
  int minute = bcdToDec(Wire.read());
  int hour = bcdToDec(Wire.read() & 0b111111); //24 hour time
  int weekDay = bcdToDec(Wire.read()); //0-6 -> sunday - Saturday
  int monthDay = bcdToDec(Wire.read());
  int month = bcdToDec(Wire.read());
  int year = bcdToDec(Wire.read());

  if((second/10)%2 == 1) {
  DisplayNumber();
  }

  if((second/10)%2 == 0) {
    kelvin = analogRead(sensorPin)*0.004882812*100;
  temperature = kelvin - 12.5 - 273.15;
  displayTemp(temperature);
  delay(10000);
  }
}


void DisplayNumber() {
    Wire.beginTransmission(DS1307_ADDRESS);
  Wire.write(zero);
  Wire.endTransmission();
  Wire.requestFrom(DS1307_ADDRESS, 7);
  int second = bcdToDec(Wire.read());
  int minute = bcdToDec(Wire.read());
  int hour = bcdToDec(Wire.read() & 0b111111); //24 hour time
  int weekDay = bcdToDec(Wire.read()); //0-6 -> sunday - Saturday
  int monthDay = bcdToDec(Wire.read());
  int month = bcdToDec(Wire.read());
  int year = bcdToDec(Wire.read());
  digitalWrite(latchPin, 0);
  shiftOut(dataPin, clockPin, MSBFIRST, ledCharSet[minute%10]);
  shiftOut(dataPin, clockPin, MSBFIRST, ledCharSet[minute/10]);
  shiftOut(dataPin, clockPin, MSBFIRST, ledCharSetDot[hour%10]);
  shiftOut(dataPin, clockPin, MSBFIRST, ledCharSet[hour/10]);
  digitalWrite(latchPin, 1);
  }

  void displayTemp(int num) {

  if (num < -10) {
    num = num*(-1);
     digitalWrite(latchPin, 0);
  shiftOut(dataPin, clockPin, MSBFIRST, symbols[0]);
  shiftOut(dataPin, clockPin, MSBFIRST, symbols[2]);
  shiftOut(dataPin, clockPin, MSBFIRST, ledCharSetDot[num%10]);
  shiftOut(dataPin, clockPin, MSBFIRST, ledCharSet[(num%100)/10]);
  shiftOut(dataPin, clockPin, MSBFIRST, symbols[1]);
  digitalWrite(latchPin, 1);
  }

  if (num < 0 && num > -10) {
    num = num*(-1);
     digitalWrite(latchPin, 0);

  shiftOut(dataPin, clockPin, MSBFIRST, symbols[0]);
  shiftOut(dataPin, clockPin, MSBFIRST, symbols[2]);
  shiftOut(dataPin, clockPin, MSBFIRST, ledCharSet[(num%1)*10]);
  shiftOut(dataPin, clockPin, MSBFIRST, ledCharSetDot[num%10]);
  shiftOut(dataPin, clockPin, MSBFIRST, symbols[1]);
  digitalWrite(latchPin, 1);
  }

  if (num < 10 && num >= 0) {
     digitalWrite(latchPin, 0);
  shiftOut(dataPin, clockPin, MSBFIRST, symbols[0]);
  shiftOut(dataPin, clockPin, MSBFIRST, symbols[2]);
  shiftOut(dataPin, clockPin, MSBFIRST, ledCharSet[num%10]);
  shiftOut(dataPin, clockPin, MSBFIRST, symbols[0]);
  shiftOut(dataPin, clockPin, MSBFIRST, symbols[0]);
  digitalWrite(latchPin, 1);
  }

  if (num >= 10) {
     digitalWrite(latchPin, 0);
  shiftOut(dataPin, clockPin, MSBFIRST, symbols[0]);
  shiftOut(dataPin, clockPin, MSBFIRST, symbols[2]);
  shiftOut(dataPin, clockPin, MSBFIRST, ledCharSet[num%10]);
  shiftOut(dataPin, clockPin, MSBFIRST, ledCharSet[(num%100)/10]);
  shiftOut(dataPin, clockPin, MSBFIRST, symbols[0]);
  digitalWrite(latchPin, 1);
  }
}

  void setDateTime(){

  byte second =      00; //0-59
  byte minute =      18; //0-59
  byte hour =        12; //0-23
  byte weekDay =     3; //1-7
  byte monthDay =    25; //1-31
  byte month =       4; //1-12
  byte year  =       12; //0-99

  Wire.beginTransmission(DS1307_ADDRESS);
  Wire.write(zero); //stop Oscillator

  Wire.write(decToBcd(second));
  Wire.write(decToBcd(minute));
  Wire.write(decToBcd(hour));
  Wire.write(decToBcd(weekDay));
  Wire.write(decToBcd(monthDay));
  Wire.write(decToBcd(month));
  Wire.write(decToBcd(year));

  Wire.write(zero); //start

  Wire.endTransmission();

}

byte decToBcd(byte val){
// Convert normal decimal numbers to binary coded decimal
  return ( (val/10*16) + (val%10) );
}

byte bcdToDec(byte val)  {
// Convert binary coded decimal to normal decimal numbers
  return ( (val/16*10) + (val%16) );
}