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What’s New
Resources
Blog
Technical articles for developers
Newsletter
The monthly Blues developer newsletter
Terminal
Connect to a Notecard in your browser
Developer Certification
Get certified on wireless connectivity with Blues
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Listing of Blues technical webinars
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Shop
Docs
Notecard
Notecard API Reference
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Notecard Walkthrough
Overview
The Notecard & Notehub
Notecard Product Family
Notecard Requests & Responses
JSON Fundamentals
Notecard Interfaces
Essential Requests
Time & Location Requests
Inbound Requests & Shared Data
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Low Power Design
Low Bandwidth Design
Working with the Notecard AUX Pins
Updating Notecard Firmware
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Notecard Error and Status Codes
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Notecard

The Notecard is a wireless IoT device that connects physical devices to cloud applications via low-power cellular, Wi-Fi, or LoRa. The Notecard automatically syncs data at user-defined intervals with the secure cloud service Notehub. Notehub can then securely route this data to any cloud application.

Rather than requiring the use of cryptic AT commands or manual byte manipulation, the Notecard API consists of JSON requests and responses. The firmware running on the Notecard implements a synchronous protocol that watches for newline-terminated (\n or \r\n) JSON requests and returns a newline-terminated (\r\n) JSON-formatted response. All interaction between the Notecard and a host microcontroller or microprocessor occurs using this JSON protocol.

For development and exploration purposes, you can interact with the Notecard through a USB Serial connection to a host computer. Examples in this guide can be run directly against a USB-connected Notecard using the In-Browser Terminal or from the Notecard CLI.

note

Just getting started?

Join our recurring Getting Started with Wireless IoT webinar series or check out the Quickstart to learn more about the Notecard.

Looking for firmware libraries?

Visit the libraries page for an SDK for your preferred language.

The Notecard & Notehub

It's important to understand a few key concepts of the Blues ecosystem:

  • The Notecard is a device-to-cloud data pump that reduces the complexity of building connected solutions with a secure, reliable cellular, Wi-Fi, or LoRa connection. It's a System-on-Module (SOM) that's ready for embedding into any project.

  • Notecarriers are development boards that help you get started quickly with the Notecard. There are a variety of Notecarriers designed to fit different needs, and many include onboard Cellular and GPS antennas, as well as a USB port for Serial access to the Notecard.

  • Notehub is the secure cloud service the Notecard uses as a proxy to send and receive data. Notehub also provides a console for fleet management and secure connectors for routing data to 3rd party cloud applications.

  • A Note is a JSON object containing developer-provided content. A Note is the primary means of sending data to/from a Notecard.

Notecard and Notehub work together to provide bidirectional wireless communication capabilities, both outbound (from your microcontroller or single-board computer to the cloud):

animation of outbound communication from notecard to notehub to cloud

And inbound (from the cloud to your microcontroller or single-board computer):

animation of inbound communication from cloud to notehub to notecard

Notecard Product Family
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Notecard Disconnected
Having trouble connecting?

Try changing your USB cable as some cables do not support transferring data. If that does not solve your problem, contact us at support@blues.com and we will get you set up with another tool to communicate with the Notecard.

Advanced Usage

The help command gives more info.

Connect a Notecard
Use USB to connect and start issuing requests from the browser.
Try Notecard Simulator
Experiment with Notecard's latest firmware on a Simulator assigned to your free Notehub account.

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