Inductive proximity sensor false readings

[Paul_B]

@xgr1mx

if I were to use a Raspberry Pi does it have the functionality to use INPUT_PULLUP ?

I don't know, but it probably does. In any case, INPUT_PULLUP is merely a convenience. You can just use a pull-up resistor.

@Idahowalker

putting 12V onto the GPIO pins of a RPI will destroy the RPi.

Which is why the diode method prevents such damage.

Fully protected circuit:

Same circuit applies to Pi or ESP with 3.3 V