I have a HyperPixel 4.0 screen working on a RPi2.
I would like to implement a button (or two) to turn-on and off the RPi.
According to HyperPixel Pinout, there is no free pin to do it. But I would like to ask if I could use any with minimal (or no) interference with normal functioning.
For example, could I use GPIO 3 (pin 5) and GND (pin 6) just to turn it on? After it, this GPIO 3 could be use for the HyperPixel. What would happen if it is connected to GND again while the screen is working?
In order to turn it off, which one could I use?
If this approach is completely wrong, what would you recommend instead?