You can read the state of a button using Arduino and a few lines of code ... You can use other pin if you want to and you can even add extra circuitry to turn ON an LED or use a relay to power up ...

We want to use four 7-Segments LEDs controlled by the Arduino board. As you can imagine ... ShiftPinNo.h> // Digital pins connected to 74HC595 int latchPin = 2; // pin 12 on the 74hc595 int dataPin = ...

(Google Translate) The wiring for this project is about as easy as you’d expect: the buttons connect to the digital inputs on the Arduino, and the LEDs on the digital outputs. When the Arduino ...

There was a point in time, excruciatingly brief, in which desktop computers often had a large “TURBO” button on their ... the state of the Turbo LED with an Arduino Pro Mini.