Arduino capteur de température LM35

Le code :

int val;
int tempPin = 1;

void setup()
{
Serial.begin(9600);
}
void loop()
{
val = analogRead(tempPin);
float mv = ( val/1024.0)*5000; 
float cel = mv/10;

Serial.print("TEMPRATURE = ");
Serial.print(cel);
Serial.print("*C");
Serial.println();
delay(1000);

}

Source : http://www.instructables.com/id/ARDUINO-TEMPERATURE-SENSOR-LM35/