3. Powering an LED
The first thing we're going to do is use our Arduino to power an LED light. You should have one yellow or red LED, plus a 330 OHM resistor. We'll hook our LED up to the 5V pin on our Arduino to power it, and use the resistor to reduce the current to the light.
The polarity (which way you plug in) on the LED matters! The long side with the round edge on the top is positive (hooked up to the power source) and the shorter edge with the flat side on top is negative (hooked up to the ground).
Don't mix them up and fry my LED :).
- Using a red wire connect the 5V pin on the Arduino to the "+" (power) row of your breadboard. This pin outputs 5 volts of power.
- Use a black wire to connect one of the ground pins on your Arduino to the "-" (ground) row on your breadboard.
- Pick two numbered rows on your breadboard next to each other.
- Use the resistor (you may have to bend it, that's fine) to connect the "-" row on the breadboard to one of the numbered rows you picked.
- Plug the short (negative) end of the LED into the same row you connected the resistor. Plug the long end into the other row.
- Connect a wire from the row with the positive (long, round) end of the LED to the "+" row on your breadboard.
- Connect your Arduino to a computer with the USB cord.
- Light!
That was a basic circuit to power an LED, next we'll get a little fancier by using a short computer program to make the LED flash.
Next up: Blinking LED »