Using Interrupts on Raspberry Pi Pico with MicroPython

Hey there! In this fun session, we’re diving into using interrupts to control an LED with a switch, building on what we’ve done before.
So, when you press that button, it’s going to toggle the LED on and off, making it super easy to track each press.
This means we’re using those interrupts to manage the LED like pros! Plus, we’ll take a stroll down memory lane and tweak some of our previous code to bring these techniques to life..

To kick things off, we use the Pin class from the machine module to handle the input and output pins on our microcontroller—pretty handy stuff! Then, we sprinkle in the sleep function from the time module because, let’s be real, delays are sometimes necessary in our programs.
For our setup, the LED is wired to pin number 25, which follows the same configuration as before.
Meanwhile, our trusty button, acting like a switch, is connected to pin number 14, set up as an input pin to keep everything running smoothly.
Lastly, we initialize a global variable to a default state of 0, making it accessible throughout the program for all our needs..

So, let’s break down how to set up interrupts to control an LED, shall we? First off, we’re diving into using the IRQ method , which gets triggered on a falling edge —this basically means when your input changes from a high signal to a low one, an automatic call to a specific function will happen.
This function is cleverly named onHolding and it’s all about using a global variable .
You’ll want to declare it with the global keyword to make sure it can be tweaked inside the function.
Plus, we throw in a quick sleep of 0 seconds; this little trick boosts the efficiency of our program and keeps us from missing any super quick input signals.
Oh, and we can’t forget about toggling—the act of flipping between two states like on/off.
To help with that, we use a pull-up resistor to ensure a high logical level when there’s no input signal, which keeps everything nice and stable..

Alright, let’s talk about how the LED is doing its thing! When you press the button, the LED turns on, and pressing it again makes it turn off – pretty cool, right? This is exactly what we expected based on the design and coding, which means our setup is a success! As soon as the button is hit, the function kicks in and changes the state from high to low, so it clearly reacts well to the interrupt trigger.
Plus, the state variable updates with each press, smoothly alternating between 0 and 1, giving you that nice on and off toggle of the LED..

In this session, we dove into the exciting world of Raspberry Pi and learned how to control an LED and switch using MicroPython.
A key highlight was managing the switch through interrupts, which really gives you a cool peek into how responsive programming can be.
To wrap things up, we teased that there’s even more to come next time, hinting at another fascinating topic we’ll explore in our ongoing journey of learning.
Stay tuned!.