

When the pushbutton is open (unpressed) there is no connection between the two legs of the pushbutton, so the pin is connected to ground (through the pull-down resistor) and we read a LOW. The other leg of the button connects to the 5 volt supply.

That same leg of the button connects through a pull-down resistor (here 10K ohm) to ground. The third wire goes from digital pin 2 to one leg of the pushbutton. The first two, red and black, connect to the two long vertical rows on the side of the breadboard to provide access to the 5 volt supply and ground. HardwareĬonnect three wires to the board. This example turns on the built-in LED on pin 13 when you press the button.

Pushbuttons or switches connect two points in a circuit when you press them.
