By the way I found that 100kHz is fast enough for my needs so I stepped down the speed.
First of all, switch should never be connected directly in parallel with capacitor
It's not. The connector for the switch is on the right, the label on the left goes to the RPi.
Adding ferrite as shown is a borderline with ridiculous.
Could you explain why? Newbie here.
Relying on internal pull-up is not reliable solution.
Again, please explain why.
Also I cannot find any info about raspberry pi having Schmitt trigger on it's GPIO
It does not.
if that is the case, just adding capacitor does more harm then good.
Again, please explain why.
Just in case, debauncing can be done in software without any external circuit.
It is.
If you just want ir for radiated EMI and not debounce
EMI is the main emphasis.
then sure that EMI won't come from GPIO which is configured as input.
Couldn't it come from coupling from elsewhere on the board?
I would rather care what is happening with the ground.
Such as what? Help please.
Thanks!!