Getting Started with ESP32

This guide teaches you how to get started using ESP32 devices with Atmosphere. This includes creating your first project, programming the project’s firmware into your ESP32, registering the device to Atmosphere, and having its data displayed on a dashboard.

This guide demonstrates a simple project that blinks a development board’s LED and reads an ADC pin once a second.

Prerequisite: You should already have an Atmosphere account.

Hardware Requirements

  • Espressif ESP32-based device
  • Tablet or smartphone mobile device

For the purposes of this guide, we used the Adafruit Huzzah ESP32 Feather Board, but any development board using an ESP32 module will work.

Software Requirements

  • Atmosphere IoT app. The mobile app allows you to view your registered devices and display and run the project’s interface. You can download the Atmosphere IoT app from its downloads page or through the Apple App Store or Google Play Store.
  • Atmosphere IoT Agent. The Atmosphere IoT Agent is a local application that runs in the system tray and acts as an intermediary between the computer’s connectivity protocol drivers and the browser running Atmosphere, used to assist in programming your device. You can download the Atmosphere IoT Agent from its downloads page.
  • Ensure Bluetooth is enabled on the mobile device you’ll use to interact with the ESP32. This project only uses the ESP32 with Bluetooth Low Energy.

Step 1 of 9: Create a New Project

Navigate to Atmosphere Studio from the side menu. When you visit Studio for the first time in a session, you are brought to the Studio Projects screen.

  1. Click theNew Projectbutton. This displays a New Project window.
  2. Give the project a name. Then select the Espressif ESP32 project type and click Create.

This opens a new project in Studio.

This guide walks through the step-by-step process to perform actions in Studio, but doesn't cover the in-depth aspects of Studio itself. To learn more about using Studio, its areas and features, and Studio elements, visit the Atmosphere Studio section.

Step 2 of 9: Create the Project’s Embedded Firmware

The first aspect of building this sample project is adding elements to Embedded View to create the project’s embedded firmware. This involves setting an interval to read embedded data, and to tell the interval to read the board’s GPIO and ADC pins.

  1. Add the following elements to the canvas by double-clicking them in the Element Toolbox:
    • Interval ElementInterval element: The interval element sets the project to run at the time set in the element’s properties, which by default is set to once per second (1000 ms).
    • ADC Pin ElementADC pin element: The ADC pin element reads the board’s ADC pin. By default this is set to the corresponding ADC pin.
    • GPIO BlementGPIO pin element: The GPIO pin element reads the board’s GPIO pin. By default this is set to the GPIO pin associated to the board’s LED.

      Each of the elements will work as intended by default, so none of their properties need to be changed.
  2. Connect the interval element to the GPIO element. This creates an event between them, which can be seen in either the interval element’s properties, or by clicking the connector’sConfiguration Buttonbutton. The event added is within the Interval trigger, with the GPIO pin ability Toggle. This means that when the interval element is triggered (which is every second), it will toggle the GPIO pin.
  3. Connect the interval element to the ADC pin element, which also creates an event between them, Read Raw. This event will read the raw ADC value when the interval element triggers.
  4. Add aBLE Characteristic ElementBLE characteristic element to the canvas, which creates a GATT characteristic to use in your project. This element is a coupled element that bridges the project between Embedded View and Application View, meaning it’s included on both views. Select the BLE characteristic element, and change the Read Data Type field to Unsigned Integer. This reads an unsigned integer, which is the ADC value sent to it.
  5. Connect the ADC pin element to the BLE characteristic element, which ties the value of the ADC pin to Application View. This creates an event between the two elements of Set Value, which sets a value for the project’s interface after it reads the raw ADC pin value.

That’s all for work in Embedded View. To this point, an interval has been set that will run once per second after the project opens, and when run will both toggle a GPIO pin and read an ADC pin. The Embedded View canvas should resemble the following image:

step 2 of project

Step 3 of 9: Create the Project’s Interface

The second aspect of building this sample project is adding elements to Application View to create the project’s visual component.

Click Application View to move to the application area of the project. Notice how the Element Toolbox has changed, and that the coupled BLE characteristic element is displayed on the canvas.

  1. Click theInterface Builderbutton in Application View’s toolbar to display the interface builder. This area creates the visual interface for your project. By default this uses the smallest display size supported for an interface (320x560), but you can add an interface size by clicking theadd displaybutton. Use the display size that fits best with your mobile device.
  2. Add anInterval Elementinterval element to the canvas, and connect it to the existing BLE characteristic element. This creates the trigger event Read, which reads the value of the BLE characteristic element sent from Embedded View every time the interval triggers.
  3. Add aLabel Elementlabel element to the canvas. The label element displays text on a project’s interface. Notice when the label is added to the canvas, a corresponding interface component is added to the interface builder. The label component can be moved around on the interface wherever you like.
  4. Connect the BLE characteristic element to the label element. This creates an event between the two elements of Set Text under the Read trigger, which sets the text to the value of the label when the BLE characteristic is read. This correlates the set value from the BLE characteristic element in Embedded View to the label on the interface.

This is all that needs to be done for the project’s interface, simply using a label to display a text value. To this point, an interval has been set that will read the BLE characteristic value once per second, which will display the read value on the interface label. The Application View canvas should resemble the following image:

step 3 of project

Step 4 of 9: Enable the Project’s Cloud Connectivity

The third aspect of building this sample project is to enable it for cloud connectivity. This is done both on Application View and Cloud View

  1. While still in Application View, add aCloud Event Elementcloud event element to the canvas. The cloud event element is a coupled element between Application View and Cloud View that enables a project’s data to be sent to Atmosphere.
  2. Connect the BLE characteristic element to the cloud event element. This adds the event Send to the Read trigger, which sends the set value data to Atmosphere when the BLE characteristic is read.
  3. Click Cloud View to move to the cloud area of the project. Notice how the Element Toolbox has changed, and that the coupled cloud event element is displayed on the canvas.
  4. Add aCloud Storage Elementcloud storage element to the canvas, and connect the cloud storage element to the cloud event element. This allows Atmosphere to store data sent to it from the connected cloud event element.

That’s all for creating the project! With the added cloud connectivity, the project will send the ADC pin value from Embedded View to Application View, which then uses a cloud event to send it to Cloud View, where it’s connected to a cloud storage element to store the data on Atmosphere.

The final canvas for each view should resemble the following images:

Embedded View Application View Cloud View
step 2 of project step 3 of project step cloud of project

Step 5 of 9: Compile the Project

Once the project is finished, it needs to be compiled. Compiling readies the entire project’s source code for deployment.

  1. From any view, click theCompilebutton in the project options menu on the top-right of the screen. You’ll see a loading graphic on the screen, and will receive a notification when the project is compiled.

Step 6 of 9: Program Firmware into the Device

With the project compiled, your ESP32 can be programmed with the project’s embedded firmware.

Prior to programming a device, ensure you have the following configuration:

  • The device is connected to the computer via USB to an available communication port.
  • The computer has Bluetooth enabled.
  • The Atmosphere IoT Agent is installed on the computer and running.
  • An Internet connection is maintained.

With setup complete, you can program your board:

  1. While Embedded View is active, click theProgram Firmwarebutton from the view’s toolbar. This displays the Program Firmware window.
  2. Under Device Port, select the communication port the device is connected to.
  3. Click Program to start programming. When complete, you’ll receive a notification stating the device is programmed with the project’s embedded firmware.

Once the device is programmed, the LED will begin toggling on and off!

Step 7 of 9: Register the Device

With firmware installed, the device can now be recognized and connected to Atmosphere. From here, open the Atmosphere IoT app on your mobile device. We’ll use the mobile app to both register the device, and eventually view the label data on the project’s interface.

To register a device:

  1. Navigate to the Devices page, and click theRegister Devicebutton in the top-right to display the Register Devices window. When the window opens it will automatically begin scanning for available devices within range.
    • Ensure your ESP32 is within range from the device you are attempting to register from, otherwise it may not appear.
    • If you want to connect the ESP32 over Wi-Fi, you can configure Wi-Fi network settings at this point. If Wi-Fi settings are entered, the device will connect to Atmosphere over Wi-Fi and remain connected as long as the Wi-Fi connection is maintained.
  2. The list of available devices appears. Select your device you just programmed and click Register.

The device is registered to Atmosphere and displayed on your Devices page.

Step 8 of 9: View the Project Interface

Each registered device has its own dedicated dashboard, which displays its information and is where you access the device’s interface to interact with it. Select your newly-registered device on the Devices page to access its dashboard.

The interface created in Studio’s Application View is available on a device’s dashboard to interact with it. As long as the device is powered on and connected to Atmosphere, it can be interacted with.

To display the interface you created, click theInterfacebutton at the top of the screen. This opens the project interface from within the Atmosphere IoT app.

The project’s interface displays the ADC pin value, which updates once per second.

If your ESP32 is connected over Wi-Fi and you open the project's interface, the device will temporarily disconnect from Wi-Fi and connect using BLE instead. This is because the ESP32 can't simultaneously maintain both connections, so BLE is used while interacting with the device and its interface. Once you leave the interface, the BLE connection is closed and the device reconnects over Wi-Fi.

Step 9 of 9: View Device Data

Now that the device’s data is sent to Atmosphere, let’s view it through one of the many device dashboard widgets available. In this guide we’ll use a data graph to chart the ADC reading.

  1. To add a widget to the device’s dashboard, click theConfigurationbutton on the side of the page. This displays the menu of available widgets. Select theData Graphdata graph widget to add a graph to the dashboard.
  2. Once on the dashboard, click the widget’sSettingsicon to display its settings.
  3. Give the data graph a name, and then select the Timestamp for the graph’s x-axis data (timestamp is the time the server receives the data) and Value for its y-axis data, then click Okay.

This populates the data graph plotting the value of the ADC as time progresses. If you have a means of manipulating the ADC on your development board, you can see the value change more drastically along the graph.

Congratulations, you just finished a complete ESP32 project with Atmosphere!