LED Blink using built-in LED

LED Blink using built-in LED

Main Diagram

HARDWARE REQUIRED:

  • PICUNO Microcontroller board (built-in LED on GPIO 14)
  • USB cable (for power and programming)

Description

The LED is controlled using digital output on GPIO 14. In the first method, it turns ON and OFF every 1 second using a blocking delay. In the second method, the code checks elapsed time using a timer and toggles the LED without stopping the program, which is useful for multitasking.

Circuit Diagram

Circuit

  • Connect the PICUNO board to the computer using a USB cable.
  • No external wires or breadboard are required.
  • The built-in LED is already internally connected to GPIO 14 of the PICUNO board.
  • The code simply sets GPIO 14 as output and toggles it in a loop to create the blink effect.

Schematic

This project uses the built-in LED on GPIO 14 of the PicUNO board. No additional circuit components are required.

Code - C

int ledPin = 14;

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

void loop() {
  digitalWrite(ledPin, HIGH);
  delay(1000);
  digitalWrite(ledPin, LOW);
  delay(1000);
}
pinMode(14, OUTPUT) - Sets GPIO 14 as an output pin.

digitalWrite() - Sets the LED state.

delay() - Introduce a fixed blocking pause.

Micropython

from machine import Pin
import time

led = Pin(14, Pin.OUT)

while True:
    led.toggle()
    time.sleep(1)
Pin(14, Pin.OUT) - Sets GPIO 14 as an output pin.

time.sleep() - Introduce a fixed blocking pause.

led.toggle() - Toggle the current state of the LED.