You can use an external one or use the one soldered on the board (pin 13). Turn ON an LED Sketch This is a very simple arduino project where a led is turned on by setting the pin 13 as output, then ...

The circuit is an Arduino RGB LED controller running on a sweet ‘n’ simple code,but with a little hardware surprise outside the Arduino board. You can add a bit of luxury to your aquarium or flower ...

As you might imagine, the design is rather simple. On the front edge of the PCB you’ve got the prerequisite IR LED, and a healthy supply of tactile buttons that your code can use as input.

An Arduino is a popular open-source single-board microcontroller. Learn how to program one and let the possibilities take shape. By The Big Book Of Hacks Published Jan 10, 2013 3:00 AM EST Get the ...

In recent episodes, she taught her audience how to build squishy circuits with LEDs and a heartbeat-sensor pendant using LilyPad, an Arduino microcontroller board designed for textiles.