Beginner

Blink an LED with Arduino Uno

You'll need an Arduino Uno, an LED, a 220ohm resistor and two jumper wires.

Step 1: Connect the LED's long leg through the resistor to pin 13, and the short leg to GND.

Step 2: Upload the sketch below and watch it blink.

Code

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);
}

void loop() {
  digitalWrite(LED_BUILTIN, HIGH);
  delay(1000);
  digitalWrite(LED_BUILTIN, LOW);
  delay(1000);
}

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Blink an LED with Arduino Uno

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