sighrobot

/* Ping))) Sensor
  
   This sketch reads a PING))) ultrasonic rangefinder and returns the
   distance to the closest object in range. To do this, it sends a pulse
   to the sensor to initiate a reading, then listens for a pulse 
   to return.  The length of the returning pulse is proportional to 
   the distance of the object from the sensor.
     
   The circuit:
    * +V connection of the PING))) attached to +5V

sighrobot

long previousMillis = 0; // store last time LED was updated
long interval = 100; // blink interval (milliseconds)

void setup() {
  
  pinMode(2, INPUT);
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  
  digitalWrite(4, HIGH); // start with one LED on