wvmarle:
A p-channel MOSFET (like PNP transistor) is for switching high side (positive line of a battery/power supply).An n-channel MOSFET (like NPN transistor) is for switching low side (negative line of a battery, GND of a power supply).
Also the gate voltage has to be handled accordingly.
Thank you very much ! It reminds me of something at school when we were designing logic gates from transistors, now I see what you mean.
So I will buy a new P-Channel FET with a low enough VGS(TH) value, and a NOR gate.
MorganS:
You know a regular useless box turns itself off when the arm retracts? There is always a second, hidden switch.
Indeed, I have seen the schematics of regular useless boxes with two switches (a hidden microswitch inside the box) used to turn off the useless box and reverse the polarity of the motors. Those don't even need a microcontroller to operate. But I didn't want the same behavior on each utilisation, so I use a microcontroller + a random function with a certain number of scenarios.