The Smart Garage Door Opener – Part 2

In this tutorial series, we are upgrading our garage to a smart garage by building and installing our own smartphone-controlled smart garage door opener. Please go and review Part 1 before coming to Part 2.

If everything is working from Part 1 you should have a working Gateway that communicates wirelessly to your first Node. We will now work through how to connect this Node to your garage door. Part 1 is difficult so if everything is working congratulations. It will get easier from here on.

Before we move on, be sure to have the following hardware ready. You should have these components from Part 1.

You will need to make sure you have properly connected hardware before you continue. This tutorial assumes you have a NODii Extender soldered correctly to your NODii 2.  We also assume you have purchased a NODii Relay Switch separately or with our NODii 2 Relay Switch Kit.


Now plug in your NODii Relay Switch into the USB port of the NODii Extender.


We will now test this relay switch to make sure everything is working properly. You can download the relay test code from our NODii Github account or go here and copy and paste the code into a new sketch. Before you upload this sketch to your NODii Relay Switch make sure it’s connected to the computer using your USB cable.  Now upload this sketch to your NODii Relay Node.

If everything is working the relay should start to make a clicking sound every 10 seconds.  This is a good sign. It means your switch is working. The code is pretty straight forward – turning ON (ie’ HIGH) for 10 seconds and turning OFF (ie; LOW) for 10 seconds before starting all over again.


We will now install the program that will run on your Gateway to talk to your NODii Relay Switch.

  1. First, download the GW32u4-433-Relay.ino sketch from our NODii Github account.
  2. Please make sure the Gateway is plugged into your computer and you have detached the NODii Relay Node from your computer.
  3. Upload this sketch to your Gateway.
  4. Open the Serial Monitor. See if you see “Sending OPEN” and “Sending CLOSE” text. If you do not a review is needed.


We now move on to programming the Relay Node.

  1. Detached the Gateway from the computer and attached the Relay Node.
  2. Download the ND32u4-433-Relay.ino sketch from our NODii Github account.
  3. Upload that sketch to your Relay Node.
  4. Open the Serial monitor and you should see the following.


Congratulations. I have a Relay Switch which is operating with your Gateway.  The last part is to wire up the Relay node to your garage door.


We will now begin the final installation process for wiring up and install your Smart Garage Door Opener. As noted at the beginning of this tutorial series. You need to have a wired garage door button for this to work.

IMPORTANT: Turn off the power to your garage door opener.

Next – remove your garage door button. The button looks like this.


Now unscrew the 2 wires that are connected to the underside of your garage door.


Take these 2 wires and insert them into the Terminal Block (blue connector) of your NODii Relay Switch. If you have 3 screw holes – connect one wire to the middle terminal and one wire to the N.O. terminal. Once you are done, it should look like this.


Now attach a battery source to your NODii Relay node. There are 2 battery options on the backside. We are using a Li-Po battery given the NODii includes a Li-Po battery recharger onboard.


Now attached the Relay Switch to your Relay NODii with the attached battery. Now plug in your Gateway to your computer.  Your garage door should start to open and close automatically.  Congratulations! You now have a smart garage door opener that is being controlled by a software program that you can change and enhance.

Now go make something.

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