Make an IoT button to send mom a message to her mobile

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Make an IoT button to send mom a message to her mobile


Do your parents call you every day, asking if you got home from school? It’s a drag, but they simply worry about you. Make a button with which you can always send a simple message to their mobile. 📲

In this project, you will learn how to use the button to send a message to your parents’ mobile. 👩👱

You will need the box with the button and the USB dongle. You can do with the basic HARDWARIO set, the Starter Kit.

Get it started in the Node-RED

  1. Put together the Starter Kit and pair it: if you are doing this for the first time, we have prepared a simple guide here. For the Core Module, you need the radio push button firmware. If you don’t know how to download the firmware or what it is, you will find out here.
  2. In the Playground, click on the Functions tab, where you find the Node-RED programming desktop.
  3. Place a light purple bubble, or node, in the desktop. You will find it on the left as Input MQTT.
MQTT input node
  1. Inside the node you will set up a key feature - which is pressing a button. Double-click on the node and copy this line into the Topic field:
MQTT topic

Confirm it with the Done button.

Tip: Instead of copying the line from here, you can simply copy the line that appears in the Messages tab after pressing the button.

Set up your message

  1. You can set up your message also here in the Node-RED. Drag the yellow node from the Functions section called Change anywhere next to the light purple MQTT input.
Change Node HARDWARIO Playground
  1. Double-click on the node and write the message for your parents into the Rules field. Just be careful, Blynk doesn’t display any diacritics. Little inspiration:
    • Easy. I’m home and safe.
    • A celebrity came to visit….just kidding, it’s me.
    • I was bitten by dogs, kidnapped by a UFO, but I made it home.
HARDWARIO Playground MQTT messages

Confirm it with the Done button and link both nodes by dragging the mouse from one bubble to the other. 🐁

Set up an app on your mobile

  1. Borrow a smartphone from your mom or dad and make it yet a bit smarter. 🤓 They must have the Blynk app on their phone to be able to see your message.
  2. Select Notification in the new project. The notification will be added to your desktop.
Blynk Notify
  1. Just press the Play triangle in the upper right corner and return the mobile to your parents.

Connect the mobile with the box

  1. Go back to your computer. On the Node-RED desktop, add the dark green Notify node behind both nodes. You can find it on the left in the Blynk ws section.
  2. Open the node by double-clicking it. You’ll see a small pencil on the right. Click on it and a new window will open. In the Auth Token field, copy the token you have sent to your email. Copy Blynk Cloud Server from the bottom window into the URL field, ws://
Blynk Settings

Confirm the settings by pressing the Add and Done buttons.

  1. Connect the node and Blynk with the yellow node where you have set the message. Now you have programmed the device so that pressing the button on the box ➡️ turns into a message ➡️ that goes all the way to your parents’ mobile. 👾
Connect nodes in HARDWARIO Playground

❗ Start and confirm the entire flow with the red Deploy button on the top right. 🚨

And… Action!

  1. Press the button. A message popped up on your parents’ mobile. 💪
Get Notification on Phone
  1. Not only will your parents think you are gifted but you will also avoid their daily phone calls. 🎉 And that’s just so smart, it must be IoT. 🕺