This wiring guide matches the .ino arduino code titled “NESPi NDEF Reader/Power Controlller v0.1 [mike.g|jun2016]” and python code titled “NESPi Cart Reader v0.1 by mike.g”. Be sure to test the rPi power circuit with a multimeter after assembling before wiring into your rPi.
Note 1: This schematic is a draft, see comments for latest revision.
Note 2: The MOSFET part numbers listed are for surface mount kind, you can substitute with most any through hole package that supports 5 volts or more.
Note 3: This wiring diagram will become outdated if and when Mike posts updated arduino code.