Digital Inputs and Outputs with GPIO in MicroPython

In this tutorial, we are going to see how to use GPIO pins in MicroPython, and how to use them as digital inputs and outputs.

GPIO (General Purpose Input/Output) are digital pins on a development board that can be configured as inputs or outputs.

These pins allow the board to interact with external devices, such as LEDs, buttons, sensors, and actuators.

Configuring a GPIO Pin

In MicroPython, GPIOs are managed through the Pin class, which provides us with the methods to configure and control the pins.

To use a GPIO pin in MicroPython, we first need to import the Pin class from the machine module.

from machine import Pin

Once imported, we can now configure the pin as an input or output, and use the functions through the Pin object.

Digital Output

Let’s start by seeing how to use a pin as an output. For this

Let’s see it with an example

led = Pin("LED", Pin.OUT)  # Configures the LED as an output

another_led = Pin(6, Pin.OUT)  # Configures pin 6

Now we can use the value() method or on() and off() to control the state of the pin.

led.on()      # Turns on the LED
led.value(1)  # is the same as on()

led.off()     # Turns off the LED
led.value(0)  # which is the same as off()

Digital Input

Now let’s see how to use a pin as an input. It’s basically very similar,

Let’s see it with an example.

my_input = Pin(4, Pin.IN)  # Configures pin 4 as an input

Once we have the pin configured, we can use the value() method to read the state of the pin.

state = my_input.value()  # Reads the state of the pin

Practical Examples

from machine import Pin
import time

led = Pin(2, Pin.OUT)  # Configures pin 2 as an output

while True:
    led.on()  # Turns on the LED
    time.sleep(1)  # Waits for 1 second
    led.off()  # Turns off the LED
    time.sleep(1)  # Waits for 1 second