## Introduction: Final Project LED Happy Face

Welcome to my happy face project! This Instructable is a slightly-more-than-beginner Arduino project designed for anyone who just wants to have fun with electronics. This Arduino project involves using 8 LEDs that light up from left to right in the shape of a smiling face. I chose to create this in spirit of the rapidly approaching end of the current school year. Even though I enjoy teaching, thinking of summer makes me happy, which served as the inspiration for this project.

Click here to view the code for this project in Arduino Create.

Intro song: McFerrin, B. (1988). Don't worry be happy. On Simple Pleasures [On Spotify]. Capital Records Inc.

## Step 1: Gather Your Materials

For this project, you will need:

• 10 jumper wires (2 black, 2 green, 2 red, 2 yellow, and 2 white)
• 8 560 ohm resistors
• 8 LEDs (6 red and 2 green)
• Arduino
• USB cable

## Step 2: Use LEDs to Create a Happy Face

Using your 8 LEDs, create a pattern in the shape of a smiling face. For mine, I used the 2 LEDs as the eyes and the 6 reds for the mouth.

While positioning the LEDs, have the legs vertical from each other with the cathode (the long end) on the bottom. The way that the legs are facing are crucial to this project working successfully!

## Step 3: Connect to the Ground

Using the 2 black jumper wires, connect the ground (GND) to BOTH negative rails on the breadboard. Since we have LEDs on both halves of the breadboard, we need to power to be brought to both sides.

## Step 4: Add the Resistors

Since power will be traveling to each LED, each light needs its own resistor. For each LED, its resistor hooks into two places: the nearest negative rail and somewhere on the same horizontal row as the shorter leg of the LED that it corresponds with.

## Step 5: Add the Jumper Wires

Now that all of the LEDs have a resistor, each one now needs to be hooked up to the Arduino, which is where the 8 other wires come into play. Grab one jumper wire, put one end in the same row as the anode of the left eye green LED (preferrably to the left of it so the cables don't get too tangled) and plug the other end into pin 13 on the Arduino.

Repeat this process for all of the other LEDs using the following rules starting with the left side of the smile and working to the right and finishing with the other eye.

• The first LED of the smile connects to pin 12
• The second LED of the smile connects to pin 11
• The third LED of the smile connects to pin 10
• The fourth LED of the smile connects to pin 9
• The fifth LED of the smile connects to pin 8
• The sixth LED of the smile connects to pin 7
• The right eye of the face connects to pin 6

Hint: once you get to the right side of the smile, try placing the breadboard side of the jumper wires to the right of the LED.

## Step 6: Power Up and Code!

Connect your Arduino to your computer with the USB cable, open up an internet browser and go here to find the code for this project.

Once the Arduino is plugged in, click on the "Upload and Save." You should now have a lovely lighting up happy face!

Troubleshooting:

If your Arduino is not lighting up like mine did in the introduction video, make sure to check a few things:

• All of the components are fully connected to the breadboard.
• Are your resistors connected to each short end of the LED? They need to be!
• Are your jumper wires connected to each cathode of the LED? They need to be!
• Check the order in which you plugged in your jumper wires. If the lights are lighting up in the wrong order, check your pin order.