Introduction: Triggering IFTTT From Arduino Using Lithouse

About: Control your home with ease

In this instructable, we will build a motion detector and trigger IFTTT events from that device.

You may create IFTTT recipes for receiving email if someone is inside the house or switching a Belkin WeMo when you walk into a room.

As the motion detector cannot directly contact IFTTT, we will use Lithouse as the broker.

Step 1: DIY Motion Detector

You will need the following components:

  • LED, Breadboard and some Wires.

Please connect these components as shown in the image.

  • Mount the Ethernet Shield on Arduino.
  • Connect the 5V and GND pin of the PIR to the respective heads of the Arduino Ethernet Shield.
  • Connect the PIR’s output pin to the pin #2 of the Ethernet Shield.
  • Connect the negative (short) leg of the LED to GND of the Shield.
  • Connect the positive (long) leg of the LED to one of the end of the 330 Ohm resistor.
  • Connect the other end of the 330 Ohm resistor to the pin #7 of the Shield.

Step 2: Register With Lithouse

Now, let us register the device with Lithouse:

  • Go to Devices tab and click the '+' button. A new window will show up.
  • Provide a meaningful name and description for your device group.
  • Then hit Add.

Step 3: Software Setup

We are going to setup the Arduino development environment and configure the device:

  • Go to the Arduino IDE’s home folder. Then go inside the libraries folder. Now, unzip Lithouse client library here and rename it to Lithouse.
  • Launch the Arduino IDE. Open LithousePIR (File > Examples > Lithouse > LithousePIR).

You may have noticed that the device key is missing in the LithousePIR sketch:

char deviceKey [] = "YOUR_DEVICE_KEY"; 

We need to update this with an actual key.

  • Go back to Devices tab and expand the group you just created by clicking the '+' on the left of group name.
  • Then click the 'copy' icon beside the device key to copy it into the clipboard.
  • Paste the device key in your sketch.


The program is now ready. Please upload it to Arduino.
You can test by moving a hand in front of the PIR sensor. The LED should turn on.

For more information regarding setup and debugging, please visit our tutorial.

Step 4: Activate IFTTT

At this stage, the device is connected to Lithouse. But, it cannot trigger IFTTT events yet. That will happen once you activate IFTTT on Lithouse:

  • Open your profile and click on activate.
  • On the resultant pop-up, please provide your IFTTT email channel's address.
  • Once you hit Verify, you will receive a verification email from Amazon Web Service (We use AWS for sending emails to trigger@ifttt.com on your behalf).
  • Please check your inbox and accept the verification request.

Step 5: Sample Recipe

Congratulations! Your DIY Motion Detector can now trigger IFTTT events. Here is a recipe for turning on a WeMo switch. You may change the ‘that’ part of the recipe based on your needs.

Please contact us with your questions and suggestions.