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homechevron_rightExample Appschevron_rightAcceleratorschevron_rightConnected Analog Signage

Connected Analog Signage

  • CircuitPython Firmware
  • Environment Variables
  • ESP32

Use the Notecard and a Wi-Fi-capable MCU to update character values on an analog split-flap display.

This project is built around a hypothetical entity, "Blues Railway," which manages a number of train stations throughout the United States. Each station contains a set of analog split-flap displays that provide visitors with real-time departure information like city, track, time, and whether there is a delay. Departure information is set across the station using Fleet-level Notehub environment variables. Variable changes are sent to the Notecard and delivered to a Host MCU. The host MCU then uses its on-board Wi-Fi connection to communicate with the signs in the facility and update the displayed information.

To run this project yourself you'll need to:

  • Configure Notehub.
  • Purchase the necessary hardware.
  • Flash the project’s firmware.

Notehub

This project leverages the Blues Notehub.io service. As such, to run this sample you’ll need to create a Notehub account, start a new Notehub project, and configure a handful of environment variables.

Creating a New Project

  1. Sign up for a free Notehub account, if you don’t have one already.
  2. Click the blue Create Project button in the top-right corner of the screen.
  3. Give the project a name, such as "AnalogSignage", and then click the next Create Project button. Creating a project in Notehub with a name

Configuring Environment Variables

The Analog Signage project uses environment variables for sending text to a set of connected displays. Each variable is a valid JSON object with fields that the host MCU uses to configure text on a connected display.

For this project all environment variables need to be set up at the fleet level, allowing you to configure different settings on different groups of devices, if necessary.

Notehub creates an initial fleet for you when you start a new project, and you can use that for setting your initial variables.

  1. Navigate to your fleet in the navigation menu, and then click the Settings link. Location of Notehub fleet settings
  2. Click the Environment tab.
  3. Scroll down to the Fleet environment variables heading, and define the four variables: line_1, line_2, line_3, and line_4.
  4. Each variable will need a JSON value in the following format {"city":"SLC","track":"02","time":"09:55","delay":"true"}. The firmware in this repo expects keys like city, track, time and delay, while the values can be varied.
  5. With all four defined, click the blue Save button. Notehub fleet environment variables fully defined

With this your Notehub backend is fully configured, and you’re ready to start setting up your hardware.

Hardware

The following hardware is required to run the Analog Signage demo.

  • Notecarrier F
  • Notecard
  • FeatherS2 ESP32-S2 From Unexpected Maker or equivalent ESP32/Wi-Fi capable MCU.
  • Vestaboard or equivalent split-flap display.

Please note that the included firmware is optimized for the FeatherS2 MCU and Vestaboard, and will need to be customized if you select different hardware.

The Notecard, FeatherS2 microcontroller connect to the Notecarrier-F as shown in the image below.

The final assembled hardware

NOTE: For a detailed look at how to connect the hardware, refer to the Notecard and Notecarrier-F quickstart guide.

With the hardware assembled you next need to get the project’s firmware running on your device.

Firmware

The Analog Signage project has custom firmware that runs on the FeatherS2 device. As a next step, complete the firmware’s setup guide to get your firmware up and running.

On This Page

  • Notehub
    • Creating a New Project
    • Configuring Environment Variables
  • Hardware
  • Firmware

Resources

  • GitHub
  • Hackster
  • Request More Info
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