const int thermistorPin = A0;   // Thermistor Pin
const int ledPin = 8;           // LED out pin
const float R1 = 100000.0;      // R1 resistance in series with thermistor
const float Vcc = 5.0;          // Vcc voltage
const float beta = 4250.0;      // Beta of the thermistor
const float T0 = 298.2;         // Thermal difference from Kelvin to Celcius
const float R0 = 100000.0;      // Thermistor resistance at 25°C

void setup() {
  Serial.begin(9600);         
  pinMode(ledPin, OUTPUT);    // Define LED as output
}

void loop() {
  int analogValue = analogRead(thermistorPin); // Read analog value from thermistor
  float voltage = Vcc * ((analogValue)/ 1023.0); // Convert to 0-5 volts 
  float Rt = (voltage*R1)/(Vcc - voltage);
  float Tc = (1/((log(Rt/R0)/beta)+(1/T0))) - 273.2; // Calculate the thermistor resistance
  
  if (Tc > 30) {                // Change LED state if
    digitalWrite(ledPin, HIGH);
  } else {
    digitalWrite(ledPin, LOW);
  }
  
  // Print the values
  Serial.print(analogValue);
  Serial.print(";");
  Serial.print(voltage, 2);
  Serial.print(";");
  Serial.print(Rt, 2);
  Serial.print(";");
  Serial.println(Tc, 2);
  
  delay(random(500, 2500)); // Delay for 0.5-2.5 seconds
}