Tutorial 10 for Arduino: Interrupts and Hardware Debouncing

New Episodes each Monday!


Learn more about Timer Interrupts here:

This tutorial series is sponsored by element14. Check out their arduino group!

[JohnAldred]

It's refreshing to see a coder who spots and fixes his typos as he goes. Shows you know what you're doing. Too many online coding tutorials seem to just be copying from a printed script, then they run it, and spend the next 15 minutes trying to figure out why it didn't work.

[shyamsundar]

I put a 750K ohm resistor in series to the first input of the switch from the 5V power supply. The first input also connects to the D2 pin (INTERRUPT Pin) of the arduino. The second input of the switch connects to GND. Finally I put a 1uF Capacitor across the D2 pin and ground. Now set the trigger mode to 'RISING' in the code. Thats it! Worked like a charm. OPTIONALLY: You could put a 22pF ceramic cap across the switches for even better stability.

[Quiggers]

As an electronic engineer, i have to say, your tutorials are fantastic. Keep up the good work.

[markgrass]

The push button will discharge the cap almost immediately. Once discharged by the switch, it will take time to recharge to +5v. Love your tutorials! Awesome job!

[HatimThayyil]

you have a dog barking at about 10 minutes.

Your tutorial series have really helped me do a high school project.

[voicevoicelessKrzysiek]

Great tutorial, I enjoyed it a lot; had to slow down the player to 0.75, lol! I have the comment, though. It's never a good idea to put a mechanical switch in parallel to a capacitor because due to the very low internal resistance of the cap and the switch there will be a huge momentary current flowing through the switch contacts which will, in turn, wear off the contacts and cause some problems after many cycles of being pressed. It's preferable to put a switch in series with a resistor, on top of the cap and use 2 Schmitt inverters, instead.

[woodandgears]

Very well done.  I'm brand new to the Arduino, and found the ground-up tutorials clear, concise, and inspirational.  I will watch more.

[taehyunbaek]

This tutorial was just what I needed for solving my problem. I need to order some innverting Schmitt triggers. Many thanks!

[jdga]

Thanks for the video. I really appreciate the constant refresher of explanations you might have gone over in the earlier videos. Its tough to remember it all but you do a great job of refreshing the older material even as you move on.

[technodaz]

After just getting my hands on a Arduino, and well the last time I wrote any code was when I was 6 and that was GW basic your videos make every thing so dam clear and I at least get whats going on ! your the best man love your work

[jsanti]

Wow, thanks for making this series. I bought an Arduino Uno on amazon. I was all excited until I started to see what little understanding I had about the purpose of resistors and capacitors where I would have used a simple circuit. Thanks for demystifying!

[nunogarcia]

A eight year old video full of relevant information. Thanks!

[iSolarSunrise]

I am not using an arduino, but your tutorials are beyond helpful; it's fantastic!

[TheOleHermit]

Thanks! Just what I needed to know for using a multi-level RGB backlit keypad & multi-level RGB backlit rotary encoders, with LED brightness indicating gain settings. That covers ~25% of the functionality of my MIDI laser control desk (excluding the associated functions and the L&R 7" Nextion Intelligent touchscreens). 😎

[KimKristoffersen]

@Jeremy Blum Really miss these videos, they are what got me started with arduino :)

[CNKayutube]

Thanks Jeremy, helped out a lot in my situation.  i used with interrupt 0 pin2 with switch/case programming style for random effects with switch hit while still running main loop.  Take care.

[KHwellness]

I enjoyed your tutorial series, you did a great job explaining what you were doing and why, to a novice like myself. It is inspiring me to get into this. I'll be watching them over again, as well as your other vids.

Thank you!

[sciguy]

@CIPHERJAY Well it didn't cause it to stop - it's just that's only printing it out in relatively long intervals, so you never see the value change in the terminal window.

[NeonblueIndustries]

Excellent Vid Tutorial!!
Exactly the help I needed on iterupts, my circuit should work with less code and less power due to the Arduino only doing a function when it's triggered by a certain interupt instead of pollong and looking for it once per void loop.

I hope you become a teacher that Inspires many kids to make this world a better place with their new ideas.
Kick ass man!
Thank you!

[sciguy]

@raghunitin They are a little different, since the trigger has an integrated feedback loop. Think of them like a not gate with a positive feedback loop.