Analog Temperature Sensor

/****************
* Analog Temperature sensor
using an LM393 Low Power Low Offset Voltage Dual Comparator
*****************/
const int digitalPin = 7;
int analogPin = A0;

const int ledPin = 13;

boolean Dstate = 0;
int Astate = 0;

void setup() {
  pinMode(ledPin, OUTPUT);
  pinMode(digitalPin, INPUT);
  Serial.begin(9600);
}

void loop() {
  Astate = analogRead(analogPin);
  Dstate = digitalRead(digitalPin);
  Serial.print("DO: ");
  Serial.println(Dstate);
  Serial.print("AO: ");
  Serial.println(Astate);

  // if pushbutton is pressed, turn led on
  if (Dstate == HIGH)
  {
    digitalWrite(ledPin, LOW); 
  } 
  else
  {
    digitalWrite(ledPin, HIGH);
  }
  delay(1000);
}