#include <OneWire.h>
#include <DallasTemperature.h>
#include "Adafruit_LEDBackpack.h"
#include "Adafruit_GFX.h" 
#include <Wire.h>  
Adafruit_7segment matrix = Adafruit_7segment();

// Data wire is plugged into pin 2 on the Arduino
#define ONE_WIRE_BUS 2
 
// Setup a oneWire instance to communicate with any OneWire devices 
// (not just Maxim/Dallas temperature ICs)
OneWire oneWire(ONE_WIRE_BUS);
 
// Pass our oneWire reference to Dallas Temperature.
DallasTemperature sensors(&oneWire);
 
void setup(void)
{
  // start serial port - for debugging
  Serial.begin(9600);
  Serial.println("Temperature");
  
   // Start up the library for 7-seg and set max brightness
  matrix.begin(0x70);
  matrix.setBrightness(15);

  // Start up the library for temperature sensor
  sensors.begin();
}
 
 
void loop(void)
{
  // call sensors.requestTemperatures() to issue a global temperature
  // request to all devices on the bus

  sensors.requestTemperatures(); // Send the command to get temperatures

    // You can have more than one IC on the same bus. 
    // 0 refers to the first IC on the wire
    int temp = round(sensors.getTempCByIndex(0));
    
    // We need to convert the absolute value of temperature to string
    String t = String(abs(temp));
    if (t.length() > 1) {                          // If the temerature is between 10 and 99 degrees or -10 and -99...
       String t1 = t.substring(0, 1);              // ...we need the first 
       String t2 = t.substring(1, 2);              // and second digit
       matrix.writeDigitRaw(0,0);
       matrix.writeDigitNum(1, t1.toInt());        // which we plot to second and third place of 7-seg
       matrix.writeDigitNum(3, t2.toInt()); 
          if (temp<0) {matrix.writeDigitRaw(0,64);}// and if the temperature is negative, we plot the minus sign to first place.
    } else  {                                      // Other case is temperature between 0 and 9 or -1 to -9
       String t1 = t.substring(0, 1);              // Then we need only the first digit
       matrix.writeDigitRaw(0,0);
       matrix.writeDigitRaw(1,0);
       matrix.writeDigitNum(3, t1.toInt());        // And we plot it to third place of 7-seg
       if (temp<0) {matrix.writeDigitRaw(1,64);}   // and if the temerature is negative, we plot the minus sign to second place.
    }

   matrix.writeDigitRaw(2, 0x10);    // light up dot as degree sign
   matrix.writeDigitRaw(4,57);       // and the letter C to fourth place
   matrix.writeDisplay();
   delay(500); 
 
}