Pull Up/Down Resistors 

Hello and thank you very much for your comment! Glad you liked the video =)

Hello and thank you very much for your comment! Glad you liked the video =)

You're welcome! Very happy to be of help :)

You're welcome! Glad to be of help :)

Hello and thank you very much for your comment! Perfect timing then, very happy to be of help =)

You're welcome! Very happy to be of help :)

Hello and thank you very much for your comment! Glad you liked the video =)

Hello and thank you for your comment! Glad you liked the video :)

Hello and thank you very much for your comment! Glad you liked the video :)

Hello and thank you very much for your comment! I happen to have a series in which I discuss how different transistor configurations can be used to build logic gates and some simple circuits. Check it out here if you like! ru-vid.com/group/PLJse9iV6ReqhHqCqtdoY3xnnx3DbxrxL_

Hello and thank you very much for your comment! Glad you liked the video =)

Hello and thank you very much for your comment! In my (admittedly limited) understanding, the actual resistor value shouldn't matter too much. The most critical thing to pay attention to in this setup is to ensure that there is no short circuit / excess current draw, which you can calculate using Ohm's Law - I=V÷R and ensure that I is reasonable for your setup. The secondary impact of the resistance value is the response speed as described in the second half of the video. I'm not aware if there are any formulas that can be used to calculate the response time based on the resistance, but unless you have very specific requirements, a bit of trial and error will do.

You're welcome! Very happy to be of help =)

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Hi Dave, thank you very much for your comment :)

Excellent explanation 👌🏻

Hello and thank you very much for your comment and the super like! Very happy to have been of help =)

@@NERDfirst I've watched about 15 videos explaining pull up resistors and yours was the clearest and best explanation by far 💪🏻

@@Rees3901Gmail Same

Hello and thank you for your comment! These are fair points, I'll do what I can to clarify! I'm not sure that my animation shows that there's noise on the wire - It shows an electrical connection between the pin and ground. The kind of random noise we experience when the pin is floating comes from sources like electromagnetic induction. These are typically very low energy signals and therefore, the current generated is miniscule. When a voltage source is connected, the current generated is significantly higher. It "overwhelms" the noise by being the higher-energy source, exerting a greater "force" on the electrons in the conductor. When we pull down to ground, all the stray currents have a low resistance path to ground, so they "drain" that way instead of registering on the microcontroller's pin. We can use the same line of reasoning to understand why the closed switch overrides the pull-down resistor. There are two paths for the current to flow - Through the resistor to ground, or through the microcontroller pin, which has next to no resistance. Hence, most of the current flows to the pin, allowing it to register the voltage. That's what I mean by "overwhelming" the path to ground. Let me know if this makes things clearer or if you need further clarification!

Hello and thank you for your comment! Don't think of this as direction of current flow (even that has two conventions and can be drawn in "both directions"). Instead, think of this as an abstraction for which is expressed "more strongly", and what the microcontroller ultimately "sees". In reality this really is a potential divider - The voltage detected on the pin is simply the ratio of the two resistances (the latter being the miniscule resistance provided by the wire).

Hello and thank you for your comment! I'm afraid I don't know enough about your use case to properly advise. The best I can do is to refer you to the Limit Switch page of the GRBL documentation here, I see that resistor values are given: github.com/gnea/grbl/wiki/Wiring-Limit-Switches

Thank you, that helped alot 👍And Thank you for the great video.

Thank you! Glad you liked the video :)

Hello again! This isn't really about current direction (which in and of itself can be drawn in both ways). This is more about what's expressed "more strongly". I debated a little about making the diagram that way also, but it is the most logical way of doing it since ground is seen at the pin of the microcontroller without any resistance, so it takes precedence.

@@NERDfirst so, that means, in this configuration, there will be no current coming out from voltage because of the resistance ?

A small amount of current (_and_ voltage) will be present. However, in this context you can almost imagine it to be like a potential divider - The voltage detected by the pin is extremely low, and would certainly be interpreted by the microcontroller as LOW.