Arduino Uno by ecolor3388

void setup() { //UNO has a built-in LED on pin 13, and we can use the LED_BUILTIN Macro pinMode(LED_BUILTIN, OUTPUT); } void loop() { //Set the LED pin to HIGH. This gives power to the LED and turns it on digitalWrite(LED_BUILTIN, HIGH); //Wait for a second delay(1000); //Set the LED pin to LOW. This turns it off digitalWrite(LED_BUILTIN, LOW); //Wait for a second delay(1000); }