int i;

void setup() {
  // put your setup code here, to run once:
Serial.begin(9600);
pinMode(A1, INPUT);
pinMode(12, INPUT_PULLUP);
}

void loop() {
  // put your main code here, to run repeatedly:
i=analogRead(A1);
Serial.print("SENSOR=");
Serial.println(i);
delay(100);

}