Most of this project consists of using two Adafruit HalloWing boards. Each board has an onboard processor and a nice LCD display. Adafruit has developed specialized software for displaying different types of blinking, moving eyes which move in unison if the two boards are wired together.

Before creating the mask, we first need to link two Hallowings together to create a realistic pair of synchronized eyes.

Follow this guide to link and synchronize your eyes

When linking two HalloWings, be sure to leave enough length of wire between them to be able position the two HalloWings comfortably inside your mask.

You can choose from a variety of eyes, experimenting with what versions you like best. For this project we will be using the DEER eyes, to match the reindeer theme (Human, Owl, Cat, and Nauga eyes are also available). 

When you plug a HalloWing board into your computer (PC/mac/Linux), press reset so that you see a flash drive connected to your computer in the file explorer/finder named HALLOBOOT; If you see a drive named CIRCUITPY, press reset again, the drive should eject and then show up again as a new drive named HALLOBOOT.

Download the UF2 file below and drag it onto each HalloWing's HALLOBOOT flash drive (you will need to do this separately to each of the HalloWings). 

Power up your HalloWing and make sure both eyes come on.

Once you've confirmed they are working, move on to the next step of adding an LED to the circuit.

Add an LED

Using female/female 0.1" jumpers, connect the GND and V+ pins on the JST 3-PH SENSE port to the LED. 

Include a resistor with a value in the 47 ohm - 75 ohm range in the circuit (this will protect the LED). Choosing a higher resistor value will result in a dimmer LED. 

When you're finished, your circuit should look like this:

This guide was first published on Dec 04, 2018. It was last updated on Dec 04, 2018.

This page (Build the Circuit) was last updated on Nov 04, 2020.