8. LED Blink

How do you plan to solve it?

#define LED_PIN 5   // GPIO pin connected to LED

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

void loop()
{
    digitalWrite(LED_PIN, HIGH);  // LED ON
    delay(400);                   // 400 ms ON time

    digitalWrite(LED_PIN, LOW);   // LED OFF
    delay(800);                   // 800 ms OFF time
}

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