Raspberry Pi Pico W LESSON 84: Debounce Pushbutton Switches Using Interrupts

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In this class we will be using the Sunfounder Raspberry Pi Pico W Keppler Kit. It will make things a lot easier if we are working on identical hardware. the link below is to amazon, and is for the identical hardware I will be using in this entire class.

In this video, I will show you how to create a hardware interrupt on the Raspberry Pi Pico W in micropython. We will see how we can attach an interrupt to a GPIO pin, and then have it run in the background. For this example we will examine the case of a pushbutton switch. We look at the issue of switch bounce, and show how to remover the problem of switch bounce using hardware interrupt.

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#raspberrypipicow
#debounce
#micropython

[edSabio]

Thanks Paul! Your mistake on line 13 shows you are real teacher not afraid to show your human side. I made my ckt fail on the 20th attempt and need to admit my shortcomings...Thank you so

[nigelworwood]

I have always thought it was a good idea to leave in the "mistakees" and watch you sort it out. We learn so much. Now after 83-84 lessons I are now spotting the "errrors". Although for me this took a little time as I write all the global values separately.

[MrHydyr]

MY FIRST and THE BEST INSTRUCTOR in ROBOTICS!!! Great Thank You, Sir! God bless you and all your works!!

[quaternion-pi]

Brilliant solution; very clearly explained. I tried to figure it out using your homework programming hint, but folded like a Walmart chair. Thanks!

[craigflorin]

Homework is complete, but it took me 52 lines of code. It works (all the time), it's functional but too long. I used counters for the 2, 4 and 8 and reset the counters back to zero after each toggle. Can't wait to see your answer. Love the homework assignments.

[keithlohmeyer]

Great solution! I could not figure what would work even with last weeks hint. My solution worked rock solid but used a Timer.
So I folded up like a cheap Walmart lawn chair.
Thanks Paul for all you do.

[louistoweill]

I got it to work in 61 lines of code using tuples to select the pertinent values of the press variable.

[shawnlowe]

Okay I'll start - I folded like a cheap lawnchair! I could not get my head around the timing aspect

[craigflorin]

I folded up like a cheap Walmart lawn chair ... several times, with much research, and many different ways. A few minutes into the video "chalk talk", I got my ah ha moment. Good lesson. Thank you!

[امينعبدالحافظعبدالباريياسين]

Thank you and l need something from you sir
Can you make lesson about pca9685

[patrickfox-roberts]

Thanks Paul - would it work with a Volatile rather than a Global declaration in the function as none of the vars are used outside of the function?

[charlotteswift]

You-know-who obviously didn't like my previous comment containing the link to my video for lessons 83 & 84.
Therefore I'll try again - once with the link and once without. This is obviously without the link.

[quaternion-pi]

Tried to incorporate a timer, but just used an interrupt and bitwise operators.

[U_Kamrc]

Much simpler debounce:
1. detect rising edge
2. after 10ms check if HIGH

[shawnlowe]

Okay, after watching, I see where my logic error was. Going to have the homework done for next by golly!! Thanks Paul

[jeraldgooch]

Paul- do you have thoughts on integrating the pico 2 into your classes(especially when they introduce a ‘W’) version)?