Connect Raspberry Pi to Azure IoT Hub (Node.js)

In this tutorial, you begin by learning the basics of working with Raspberry Pi that's running Raspbian. You then learn how to seamlessly connect your devices to the cloud by using Azure IoT Hub. For Windows 10 IoT Core samples, go to the Windows Dev Center.

Don't have a kit yet? Try Raspberry Pi online simulator. Or buy a new kit here.

What you do

  • Create an IoT hub.

  • Register a device for Pi in your IoT hub.

  • Set up Raspberry Pi.

  • Run a sample application on Pi to send sensor data to your IoT hub.

What you learn

  • How to create an Azure IoT hub and get your new device connection string.

  • How to connect Pi with a BME280 sensor.

  • How to collect sensor data by running a sample application on Pi.

  • How to send sensor data to your IoT hub.

What you need

What you need

  • A Raspberry Pi 2 or Raspberry Pi 3 board.

  • An Azure subscription. If you don't have an Azure subscription, create a free account before you begin.

  • A monitor, a USB keyboard, and mouse that connects to Pi.

  • A Mac or PC that is running Windows or Linux.

  • An internet connection.

  • A 16 GB or above microSD card.

  • A USB-SD adapter or microSD card to burn the operating system image onto the microSD card.

  • A 5-volt 2-amp power supply with the 6-foot micro USB cable.

The following items are optional:

  • An assembled Adafruit BME280 temperature, pressure, and humidity sensor.

  • A breadboard.

  • 6 F/M jumper wires.

  • A diffused 10-mm LED.

Note

If you don't have the optional items, you can use simulated sensor data.

Create an IoT hub

This section describes how to create an IoT hub using the Azure portal.

  1. Sign in to the Azure portal.

  2. Choose Create a resource, and then enter IoT Hub in the Search the Marketplace field.

  3. Select IoT Hub from the search results, and then select Create.

  4. On the Basics tab, complete the fields as follows:

    • Subscription: Select the subscription to use for your hub.

    • Resource Group: Select a resource group or create a new one. To create a new one, select Create new and fill in the name you want to use. To use an existing resource group, select that resource group. For more information, see Manage Azure Resource Manager resource groups.

    • Region: Select the region in which you want your hub to be located. Select the location closest to you.

    • IoT Hub Name: Enter a name for your hub. This name must be globally unique. If the name you enter is available, a green check mark appears.

    Important

    Because the IoT hub will be publicly discoverable as a DNS endpoint, be sure to avoid entering any sensitive or personally identifiable information when you name it.

    Create a hub in the Azure portal

  5. Select Next: Size and scale to continue creating your hub.

    Set the size and scale for a new hub using the Azure portal

    This screen allows you to set the following values:

    • Pricing and scale tier: Your selected tier. You can choose from several tiers, depending on how many features you want and how many messages you send through your solution per day. The free tier is intended for testing and evaluation. It allows 500 devices to be connected to the hub and up to 8,000 messages per day. Each Azure subscription can create one IoT Hub in the free tier.

    • IoT Hub units: The number of messages allowed per unit per day depends on your hub's pricing tier. For example, if you want the hub to support ingress of 700,000 messages, you choose two S1 tier units. For details about the other tier options, see Choosing the right IoT Hub tier.

    • Advanced Settings > Device-to-cloud partitions: This property relates the device-to-cloud messages to the number of simultaneous readers of the messages. Most hubs need only four partitions.

  6. For this article, accept the default choices, and then select Review + create to review your choices. You see something similar to this screen.

    Review information for creating the new hub

  7. Select Create to create your new hub. Creating the hub takes a few minutes.

Register a new device in the IoT hub

In this section, you create a device identity in the identity registry in your IoT hub. A device cannot connect to a hub unless it has an entry in the identity registry. For more information, see the IoT Hub developer guide.

  1. In your IoT hub navigation menu, open IoT Devices, then select New to add a device in your IoT hub.

    Create device identity in portal

  2. In Create a device, provide a name for your new device, such as myDeviceId, and select Save. This action creates a device identity for your IoT hub.

    Add a new device

    Important

    The device ID may be visible in the logs collected for customer support and troubleshooting, so make sure to avoid any sensitive information while naming it.

  3. After the device is created, open the device from the list in the IoT devices pane. Copy the Primary Connection String to use later.

    Device connection string

Note

The IoT Hub identity registry only stores device identities to enable secure access to the IoT hub. It stores device IDs and keys to use as security credentials, and an enabled/disabled flag that you can use to disable access for an individual device. If your application needs to store other device-specific metadata, it should use an application-specific store. For more information, see IoT Hub developer guide.

Set up Raspberry Pi

Install the Raspbian operating system for Pi

Prepare the microSD card for installation of the Raspbian image.

  1. Download Raspbian.

    a. Raspbian Buster with desktop (the .zip file).

    b. Extract the Raspbian image to a folder on your computer.

  2. Install Raspbian to the microSD card.

    a. Download and install the Etcher SD card burner utility.

    b. Run Etcher and select the Raspbian image that you extracted in step 1.

    c. Select the microSD card drive. Etcher may have already selected the correct drive.

    d. Click Flash to install Raspbian to the microSD card.

    e. Remove the microSD card from your computer when installation is complete. It's safe to remove the microSD card directly because Etcher automatically ejects or unmounts the microSD card upon completion.

    f. Insert the microSD card into Pi.

Enable SSH and I2C

  1. Connect Pi to the monitor, keyboard, and mouse.

  2. Start Pi and then sign into Raspbian by using pi as the user name and raspberry as the password.

  3. Click the Raspberry icon > Preferences > Raspberry Pi Configuration.

    The Raspbian Preferences menu

  4. On the Interfaces tab, set I2C and SSH to Enable, and then click OK. If you don't have physical sensors and want to use simulated sensor data, this step is optional.

    Enable I2C and SSH on Raspberry Pi

Note

To enable SSH and I2C, you can find more reference documents on raspberrypi.org and Adafruit.com.

Connect the sensor to Pi

Use the breadboard and jumper wires to connect an LED and a BME280 to Pi as follows. If you don’t have the sensor, skip this section.

The Raspberry Pi and sensor connection

The BME280 sensor can collect temperature and humidity data. The LED blinks when the device sends a message to the cloud.

For sensor pins, use the following wiring:

Start (Sensor & LED) End (Board) Cable Color
VDD (Pin 5G) 3.3V PWR (Pin 1) White cable
GND (Pin 7G) GND (Pin 6) Brown cable
SDI (Pin 10G) I2C1 SDA (Pin 3) Red cable
SCK (Pin 8G) I2C1 SCL (Pin 5) Orange cable
LED VDD (Pin 18F) GPIO 24 (Pin 18) White cable
LED GND (Pin 17F) GND (Pin 20) Black cable

Click to view Raspberry Pi 2 & 3 pin mappings for your reference.

After you've successfully connected BME280 to your Raspberry Pi, it should be like below image.

Connected Pi and BME280

Connect Pi to the network

Turn on Pi by using the micro USB cable and the power supply. Use the Ethernet cable to connect Pi to your wired network or follow the instructions from the Raspberry Pi Foundation to connect Pi to your wireless network. After your Pi has been successfully connected to the network, you need to take a note of the IP address of your Pi.

Connected to wired network

Note

Make sure that Pi is connected to the same network as your computer. For example, if your computer is connected to a wireless network while Pi is connected to a wired network, you might not see the IP address in the devdisco output.

Run a sample application on Pi

Clone sample application and install the prerequisite packages

  1. Connect to your Raspberry Pi with one of the following SSH clients from your host computer:

    Windows Users

    a. Download and install PuTTY for Windows.

    b. Copy the IP address of your Pi into the Host name (or IP address) section and select SSH as the connection type.

    PuTTy

    Mac and Ubuntu Users

    Use the built-in SSH client on Ubuntu or macOS. You might need to run ssh pi@<ip address of pi> to connect Pi via SSH.

    Note

    The default username is pi and the password is raspberry.

  2. Install Node.js and NPM to your Pi.

    First check your Node.js version.

    node -v
    

    If the version is lower than 10.x, or if there is no Node.js on your Pi, install the latest version.

    curl -sL https://deb.nodesource.com/setup_10.x | sudo -E bash
    sudo apt-get -y install nodejs
    
  3. Clone the sample application.

    git clone https://github.com/Azure-Samples/iot-hub-node-raspberrypi-client-app
    
  4. Install all packages for the sample. The installation includes Azure IoT device SDK, BME280 Sensor library, and Wiring Pi library.

    cd iot-hub-node-raspberrypi-client-app
    npm install
    

    Note

    It might take several minutes to finish this installation process depending on your network connection.

Configure the sample application

  1. Open the config file by running the following commands:

    nano config.json
    

    Config file

    There are two items in this file you can configure. The first one is interval, which defines the time interval (in milliseconds) between messages sent to the cloud. The second one is simulatedData, which is a Boolean value for whether to use simulated sensor data or not.

    If you don't have the sensor, set the simulatedData value to true to make the sample application create and use simulated sensor data.

    Note: The i2c address used in this tutorial is 0x77 by default. Depending on your configuration it might also be 0x76: if you encounter an i2c error, try to change the value to 118 and see if that works better. To see what address is used by your sensor, run sudo i2cdetect -y 1 in a shell on the raspberry pi

  2. Save and exit by typing Control-O > Enter > Control-X.

Run the sample application

Run the sample application by running the following command:

sudo node index.js '<YOUR AZURE IOT HUB DEVICE CONNECTION STRING>'

Note

Make sure you copy-paste the device connection string into the single quotes.

You should see the following output that shows the sensor data and the messages that are sent to your IoT hub.

Output - sensor data sent from Raspberry Pi to your IoT hub

Read the messages received by your hub

One way to monitor messages received by your IoT hub from your device is to use the Azure IoT Tools for Visual Studio Code. To learn more, see Use Azure IoT Tools for Visual Studio Code to send and receive messages between your device and IoT Hub.

For more ways to process data sent by your device, continue on to the next section.

Next steps

You’ve run a sample application to collect sensor data and send it to your IoT hub.

To continue to get started with Azure IoT Hub and to explore all extended IoT scenarios, see the following: