Wiring digital sensors
This chapter needs to be written/updated/translated
Digital sensors are driven through the GPIO (General Purpose Input/Output) pins. These pins are copper connected to the CPU chip. A short circuit with 0 V or +3.3 V is not final, but any direct contact with the + 5 V (or higher) can KILL the Raspberry Pi.
Pins names are according to the diagram below.
For a normal digital sensor (open by default), you have to configure it as "Pull down" and to connect it between selected GPIO pin and +3.3v pin (DANGER, NEVER TO +5v).
For a special digital sensor (closed by default), you have to configure it as "Pull up" and connect it between selected GPIO pin and GND pin.
It is not a problem if you make a mistake connecting to GND or +3.3v but be careful and avoid the +5v pin. It isn't a bad idea to add a 1 kOhm resitor into the circuit.