Don't see your favorite hardware here? Rest assured the Notecard works with virtually every MCU and SBC available. If you can't figure out how to complete this tutorial let us know in our forum and we can help you out.
This tutorial should take approximately 40-50 minutes to complete.
In this tutorial, you'll learn how to take sensor readings from a Device and send readings to your Notecard and the Blues Wireless Notehub. You'll use CircuitPython running on a Adafruit Feather M4 Express wired up to Notecarrier-A hardware. If you would like to use a different language, board, or Notecarrier, modify the dropdowns at the top of this guide.
The tutorial uses mock sensor readings for simplicity, but feel free to hook up a physical sensor of your choice and use that instead.
If you get stuck at any point during this tutorial, the full source for each example is available on GitHub:
First, you’ll need to get all of your hardware connected. Follow the instructions below to connect your Adafruit Feather M4 Express and Notecard mounted on a Notecarrier-A.
In order to complete this guide, you’ll need the following:
- Notecard mounted to Notecarrier-A.
Any CircuitPython-capable Microcontroller (MCU) with Feather headers. We'll be using the Adafruit Feather M4 Express, but any MCU with a CircuitPython bootloader and binary will do. Be sure to follow the instructions for burning the bootloader and flashing the CircuitPython binary to your device. And if you're using the Adafruit Feather M4 Express, make sure you update your board to the lastest version of CircuitPython.
A text editor or IDE that works well with CircuitPython, like Mu or Visual Studio Code.
- Micro USB to USB-A cable.
For this tutorial, you'll be powering the Notecard through the Micro USB connection of your Adafruit Feather M4 Express. Some Feather-compatible devices cannot handle 2 Amp pulses from the Notecard when connected to GSM, so if you experience resets or other power-related issues, we suggest powering your separately through the USB or LiPo connector on the Notecarrier.
If you need additional help finding the correct I2C, Power, GND, and Serial pins on your Arduino, consult the Arduino documentation for your board of choice. The Arduino Nano 33, for instance, has the pin designations silk-screened on the bottom of the board, which makes it hard to find a pin while plugged into a breadboard. We consulted the pinout diagram here to make sure everything was wired correctly.
Now, let's connect your Notecard using a Serial connection.
Connect
V+
from the Notecarrier-A to theUSB
pin on your Adafruit Feather M4 Express.Connect
GND
from the Notecarrier-A to aGND
pin on your Adafruit Feather M4 Express.Connect
TX
from the Notecarrier-A to theRX
pin on your Adafruit Feather M4 Express.Connect
RX
from the Notecarrier-A to theTX
pin on your Adafruit Feather M4 Express.
Now that your hardware is all connected, let’s create a new Notehub project to receive sensor readings from your Notecard.
Navigate to notehub.io and log-in, or create a new account.
Using the New Project card, give your project a name and ProductUID.
NOTE: The ProductUID must be globally unique, so we recommend a namespaced name like
"com.your-company.your-name:your_product"
.
Take note of your ProductUID. This identifier is used by Notehub to associate your Notecard to your project.
Now you're ready to write some firmware. When communicating with the Notecard,
you can manually send requests using the Serial write
function and passing-in
JSON objects, or use the note-python library. The code snippets below show both,
so feel free to use the approach that works for you.
The rest of this tutorial assumes you have already burned the bootloader and flashed the CircuitPython binary to your MCU.
If you haven't, please consult Adafruit's guide for Installing CircuitPython.
Now that you've configured your MCU to communicate with the Notecard, let's grab some pseudo sensor readings.
If you have your own sensor, feel free to hook it up and use your own values instead of this tutorial's mocked ones.
Now that we're getting sensor readings, let's send these to our Notecard.
Once you start capturing readings, your Notecard will initiate a connection to Notehub and will start transferring Notes. Depending on signal strength and coverage in your area, it may take a few minutes for your Notecard to connect to Notehub and transfer data.
Return to notehub.io and open your project. You should see your notecard in the Devices view.
Now, click on the Events left menu item. Once your sensor Notes start syncing, they’ll show up here.
You’ve successfully connected your Adafruit Feather M4 Express and sensor to your Notecard!
Now you're ready to connect this Notecard project to a cloud application! Take a look at our routing tutorials, which cover a number of popular cloud applications and data visualization tools.
During this tutorial, you set your Notecard into continuous
mode, which
maintains an active network connection and enables faster syncs with Notehub.
It doesn't have much impact on data usage, but it will draw more power. If
you're connected to battery power, or want to transition your project to battery
power, then you can put your Notecard into periodic
mode with the following
request using the in-browser terminal or directly in your firmware.
{
"req": "hub.set",
"mode": "periodic",
"outbound": 60,
"inbound": 120
}