/* Blink Turns on an LED on for one second, then off for one second, repeatedly. */ void setup() { // initialize the digital pin as an output. // Pin 13 has an LED connected on most Arduino boards: pinMode 3 (13, OUTPUT 4); } void loop() { digitalWrite(13, HIGH); // set the LED on delay(1000); // wait for a second digitalWrite(13, LOW); // set the LED off delay(1000); // wait for a second }