knowledge sharing on GPIO pins

bibi

Hello! this post is not directly related to MM but can help to understand how to use the gpio pins on a RPI3. I have been playing around with MM since few months now and wanted to use the gpio pins a bit more for instance to integrate sensors etc. But my problem is the understanding of the gpio pins before plugging anything in a wrong way. If anybody want to share knowledge about how the pins works, things to consider, best practice etc, you are more then welcome
For a start I was asking myself why there are 2x (pin 2 and 4) 5V output when the Pi is only powered by 1x 5V? I assume both pins can be used independently? thx for any info

frog

@bibi there’s a lot of info webwise on the raspberry GPIO pins - I’d search on the web rather than here, but it’s true that you can use the two 5V pins - but be aware that the GPIO pins are at 3.3v - so you do need to step the voltage down on a lot of things that you would connect to. There are quite a few though that do work around 3.3v - like the PIR and sonic sensors for example.

Here is the page where I learnt all I needed to know about GPIO which could be a good start:

https://www.modmypi.com/blog/raspberry-pi-gpio-sensing-motion-detection

bibi

@frog thx a lot for your input and for the link! I agree there are lot of stuff available on the net that i have found but it’s not always clear for me as i don’t have any electronic background… and people here are very very helpful to explain and share info things like “can i use the 2x 5v pins at the same time?” or “how many things i can connect to the 1x 5v at same time?” those kind of question i didn’t find answers on the net… and i still don’t have lol so i thought i would ask here as it’s also a good playground

frog

Hi,

I understand what you say, but the gpio pins really aren’t heavily used in the MagicMirror - really so far for buttons and pir. I suggest this following forum as a better place to look as you’ll get many more people who are using the general features of the raspberry.

https://www.raspberrypi.org/forums/

bibi

hi @frog, good reference forum in my favorite already thx well my questions came cuz of course i want to use sensor, buttons etc with my MM… but i guess you understod this i agree they are more chance to find general info on that forum.

chrisyy

Maybe u can look on this page, there’s a complete documentation on the RPi pinout.
http://pinout.xyz/