Watch to learn why capacitors are used for counting 🤓 

Same pinch

50ms is where I start and then adjust as necessary.

But would that cost a delay?

Yes, but I've tried that method and (at least for my implementation) it's not as reliable as you think it is. Though if you're aiming for circuit simplicity, yes. Electronic buttons have been around for ages. There's a reason techniques like hardware debouncing stick around.

​@@ItachiUchiha-gf4fzNo, only if you suck at programming. Use a time counter (millis in arduino) or an interupt.

@@fog1257 I see, thanks! I’ll try to implement good of both worlds😁. The problem I’m seeing is that if there’s gonna be a need for precision because surely that not every project would have the same components then just programming alone might not do it all. So, I believe the most reliable one is to smooth out the current with a capacitor and or an inductor. Overall, thanks anyway since I haven’t actually integrated the two of them yet. I have learned programming and electrical separately. Soon I’ll be using Arduino to create cools stuff.

@@ItachiUchiha-gf4fz Unless you are trying to get timing down to nano seconds the interrupt sequence on a regular Arduino works just fine (micro seconds of precision), really you will not get that good timing with a lm555 with regular cheap components. The reason people like delay is because of simplicity of use but how it really works is wasteful. When you type delay(1000) you tell the processor to perform a NOP(no operation assembly) for 1000 ms. The number of operations that corresponds to is calculated in the Delay function by the number you put in times a factor based on the clock speed of the processor. That's why you can't do anything else when using a delay, the processor is busy doing nothing.. Better approach is using millis(). Millis is a function which is called by an interrupt at 1000Hz in the background and a counter is incremented and stored, like a clock. At startup the clock is 0 and then it just keeps ticking. When using millis you call it and store it into a variable like, unsigned long lastTime = millis(). We use a long here since millis() is a very large value. You can then compare this in your loop by: if(millis() - lastTime > myDelayTime) //DoSomething In short, millis() is a form of polling. Lastly we have the interrupt. Interrupt uses separate hardware which can interrupt the processor at any time to make it do something else before returning to its previous task. You can either use input interrupts so that buttons are more responsive for example or you can use timed interrupts. Interrupts are a lot harder to set up and you got to be careful so that everything is restored after the interrupt or your program will crash. For speed and multitasking, they are the best. Another thing to keep in mind is that some libraries use interrupts already and there are a limited number of interrupts since they are hardware based. So if you want to use them together with a library which also uses them you got to make sure that there are no collisions, for example if two parts of the code try to use the same interrupt for different things at the same time. If you have more questions, ask away. Good luck with your learning.

I have been trying to build a keyboard from scratch and been experiencing debouncing. Should I use this capacitor technique? If so how should I connect it?😊

​​@@Quaxyy That really depends on the application. On a keyboard, I personally would do it in software to save some effort (only allowing updates to any button every 20 ms or so should already resolve the problem). If you want to do it in hardware tho, look up the debouncing article in digikey for the IDEAL and adjustable solution (first solution on the page). To save space tho, this is the order in which I would remove elements from that circuit: D1, U1 and if you really want R2. Or you could buy dedicated IC's (third solution on the page) to save even more space.

⁠@@amos9274 hi amos, I really like your point of view, I have also used software debounce in one our projects which had the stm32. If i am not wrong we can also use SR latch circuit for eliminating the debounce of a switch. Plus i want to ask you if you have any experience with transistors or amplifiers.

​@@Gagandeepsingh-uf2unHi Gagandeep, thank you for your reply, I also currently use stm32 for nearly all of my projects :) Yes, you can use an SR latch, but only if you have a dual-throw switch/button. I do have some experience with amplifiers and transistors but it is not my specialty.

Yeah, that cap discharging into the switch will ruin the contacts of the switch in no time

does this block the programm while debounceing or not?

this method seems more reliable than software

@@flueritvI don’t know what this guy is talking about but when I implemented a software solution to denouncing I used a finite state machine that switched from high to low or something like that. While the button is bouncing you can’t do anything you have to wait until it stabilizes

@@ipodtouch470 I once tried to set a timer on Interrupt on Change from the GPIO and once the timer overflowed I captured the Value. I mean it worked and didn't block the programm but it useses one Timer per GPIO to debounce so its not very effective

Looks correct enough to me. If it's just to demonstrate the concept of bouncing, it's fine.

@@_marshP As the circuit provide use pull-up resistor, the wave form will go down fast and rise up slow. So it must keep low state during bouncing period. it does cost more or take any afford to make it correct at the first place. Making video like these cost more confusion for beginner.

The button is *physically* bouncing, it's just way too fast for you to notice

@@skmgeekI still don’t feel like that answers the question Why is it used if it doesn’t work?

This is what I was thinking and I was about to ask

@@prestonferry wdym? the button is working fine, almost all buttons experience bouncing. a pulldown resistor won't do much as the button is literally connecting and disconnecting a few times before settling down. think of it like a ball that gets dropped from a height, it'll bounce a few times before coming to a stop. using a capacitor in a low-pass filter will make it so the extremely fast bounces get smoothed out and practically disappear. Ben eater has a very good video on denouncing if you want to learn more about it

@@skmgeek oh I see, so it doesn’t need a threshold which is what a pull down resistor does, because the button physically closes a few times in less than a second? And are buttons the only components with this issue?

Software debouncing is perfectly fine and can be what makes most sense

@@runforitmanPAin in the ass tho

Yup software debounce libraries like oneButton are really helpful

this reminds of the TRS-80 back in the day , it had horrible keybounce, you could download a patch to handle it, would have nice to have a physical fix

A resistor won't slow the voltage change. Resistor will only resist current. The mcu input is such a high impedance and low capacitance that the charge between the resistor and input will change just about as fast as if there were no resistor.

for the computer it did

This button is mechanical it keeps moves up and down