linux novice needing a bit of help

korn16ftl3

hello all,

I have begun a retropie nespi+ case build with a standard raspberry pi3 (non + edition) and have ran across a few cooling issues during file transfers over the network.

the nespi+ case only fits a 30mm fan and i seem to be having issues finding a quality and quiet 30mm fan and apparently noctua doesn't make them (I'm unsure why).

This led me to a search for a pi case mod for a 40mm fan and i stumbled across the following:

https://medium.com/@olilay/how-to-keep-your-raspberry-pi-cool-and-quiet-with-a-smart-fan-ecd15f4dbf7b

i decided i like this idea and to see if there was a way to adapt a 40mm fan to the 30mm fan location on my nespi+ case and found this:

https://www.thingiverse.com/thing:3223501

so now it appears i have figured out everything i need to to make a 40mm fan work in my nespi case and not only that it will function as an actual computer cpu fan by accelerating when temperatures require it to do so.

this is where i need some help, I'm barley a novice with linux....like i copy and paste things into the command prompt because i have a hard time retyping them or do not know what to type to get the required results.

the instructions for the "smart fan" are written for an at the minimum intermediate user with a base knowledge expecting someone to know certain commands (editing txt files for example) that i do not have.

I as hoping someone would be able to simplify this so that i am able to have the gaps missing that i need to understand and perform the modification.

my first major question until i get to playing ith this and looking at how it works:

how do i install the .deb file? i know retropie is written on a heavily modified debian kernal so this should be able to be adapted to work how id like it to. what i do not know is the commands to type to have retropie obtain the .deb file and install it.

and second....im assuming that the GPIO pinout for a pi4 is the same for a standard pi3?

mitu

@korn16ftl3 said in linux novice needing a bit of help:

how do i install the .deb file? i know retropie is written on a heavily modified debian kernal so this should be able to be adapted to work how id like it to. what i do not know is the commands to type to have retropie obtain the .deb file and install it.

RetroPie is not 'written on a heavily modified deboan kernal'. It's just a collection of scripts installed on-top of an existing Linux operating system (Debian or similar distro). A .deb file is a Debian package which can be installed using dpkg - see https://man7.org/linux/man-pages/man1/dpkg.1.html.

and second....im assuming that the GPIO pinout for a pi4 is the same for a standard pi3?

Yes.

korn16ftl3

so i have gotten started with this part of my build after getting an adapter plate 3d printed and a little fiddling around....

im to the point now where the guide says to enable PWM in raspian....

"How to get smaRSt-fan to run on your Pi?
First you have to activate hardware PWM support on your Pi, as it is disabled per default. Assuming you use Raspian, you can do that by appending

dtoverlay=pwm

to your /boot/config.txt file. This will activate PWM support on GPIO 18. If you want to use GPIO 19, you will need to append

dtoverlay=pwm-2chan

instead. Afterwards, reboot the Pi."

now the PWM pin i chose to use was GPIO pin # 12 labeled on this site ( https://www.youngwonks.com/blog/Raspberry-Pi-3-Pinout ) as GPIO pin #12 = GPIO 18 PWM0

so i popped my retropie sd card into my pc and browsed the boot partition until i found the config.txt i found the dtoverlay section but it says the following:

# Uncomment this to enable infrared communication.
#dtoverlay=gpio-ir,gpio_pin=17
#dtoverlay=gpio-ir-tx,gpio_pin=18

these are apparently meant for IR functionality......

my question is how or where do i make the changes in the config.txt to enable PWM on the required pins from the guide i am trying to follow?

if i completely change this section somehow will it function like i want it to, and enable PWM readout on the proper GPIO pins?

mitu

@korn16ftl3 said in linux novice needing a bit of help:

my question is how or where do i make the changes in the config.txt to enable PWM on the required pins from the guide i am trying to follow?

Just add a line at the end of the existing config.txt with the required dtoverlay option. Lines beginning with # are just comments and will be ignored by the Pi bootloader.