Source

articles_code / arduino_article / listing1.pde

Full commit
/*
 Blink
 Turns on an LED on for one second, then off for one second, repeatedly.

 This example code is in the public domain.
 */

void setup() {
 // initialize the digital pin as an output.
 // Pin 13 has an LED connected on most Arduino boards:
 pinMode(13, OUTPUT);
}

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
}