One Board: A New Way to Build with Blues

Webinar Summary

The following summary is auto-generated from the webinar recording.

Blues is focused on making connected product design simpler. The idea is straightforward: reduce hardware and cloud complexity, speed up prototyping, and make the path to production cleaner. Notecarrier CX is the latest step in that direction — a compact, solder-down friendly board that brings a Notecarrier and an STM32L433 host microcontroller together in a single package.

What's New in Notehub

Notehub continues to evolve with features that matter when you're running fleets of devices. These updates are aimed at better routing, authentication, monitoring, and low-latency ingestion.

• Smart fleets — Automatically group devices based on ingested data using JSONata expressions. Devices can join or leave named fleets based on sensor values or other event fields, making dynamic grouping and targeted rules much easier to manage.
• Watchdog events — Define intervals after which Notehub will generate a watchdog note if a device goes silent. Great for detecting problematic devices in the field and triggering alerts via email, Slack, or other integrations.
• Personal Access Tokens — Modernized auth for Notehub API calls. You can create up to 10 tokens per user and manage token expirations. This replaces the older OAuth bearer token approach.
• Firmware UI and separation of notes vs metadata — A revamped firmware management UI clarifies which assets are notes and which are metadata, and restored some older Notecard LTS releases to ease long-term versioning.
• Test JSONata Transforms — Validate routing transforms before deploying them. Test any event against any route without performing destructive actions on live data, ensuring your JSON payloads get transformed into the correct structure.
• Snowflake / Snowpipe streaming — Low-latency option for high-frequency event ingestion.
• Improved usage reporting — Easier tracking of cellular data usage and event counts inside Notehub, plus basic satellite data tracking with more reporting improvements coming soon.

Satellite Connectivity

Interest in satellite connectivity for IoT has surged. Blues continues to expand its Starnote family to make satellite failover and global connectivity easier to integrate.

• Starnote for Skylo — A companion failover satellite device for Notecard-based products. It uses Skylo's NTN constellation and is getting an all-in-one Notecard option soon that combines cellular, Wi‑Fi, and Skylo satellite connectivity on a single board.
• Starnote for Iridium — Planned to bring global Iridium coverage to Notecard products via a companion device. The hardware will be pricier, but Blues plans to keep a prepaid, bundled-data model rather than requiring a monthly subscription.

Introducing the Notecarrier CX

Developers often ask why they can't directly program the STM32 on a Notecard or have a single compact board that does everything. There are technical and security reasons why a fully integrated, single-chip approach isn't practical. The Notecarrier CX is the practical alternative: it combines the Notecarrier X form factor with an onboard STM32L433 host microcontroller in a single, compact board.

Core Specs and Selling Points

• Host microcontroller: STM32L433 — 80 MHz Cortex-M4, low power, solid flash and RAM for embedded applications.
• Compatibility: Works with all current Notecards.
• Size: 76 × 38 millimeters, with castellated edges suitable for solder-down use in production.
• Unique hardware switch: A dip switch near the USB port selects whether USB connects to the Notecard or to the host MCU, enabling both Notecard access and host development from the same board.
• I/O and conveniences: USB-C, quick port for sensors, programmable user button, dual headers breaking out Notecard and host pins, JST battery connector, and an external SIM option.
• Price: $17.50 for the initial release. A starter kit including the CX and a Notecard is planned soon.
• Release status: Initial 1.3 release is shipping as a beta with a small set of documented errata.

Prototyping and Production

The CX is intentionally small and prototyping-friendly, but the castellated edges make it reasonable for solder-down use in production designs. That makes it a strong bridge between rapid iteration and scaled products.

Developer Workflow with Notecarrier CX

The CX is designed so the Notecard and the host MCU (the on-board Blues Cygnet) work together seamlessly. Key parts of the workflow:

1. Flip the dip switch to connect USB to the Notecard for normal interaction and serial console access.
2. Flip the dip switch to connect USB to the host to program or debug firmware on the STM32L433, using either the boot/reset buttons or a JTAG/ST‑Link probe.
3. Use the Notecard outboard firmware update workflow to push host firmware updates out through Notehub. The CX supports DFU-style metadata and card.dfu configuration so you can queue host binaries, call hub.sync from the device, and have updates downloaded and applied securely.

Flashing works like a typical Cygnet-based workflow: either use the built-in bootloader via buttons or an external ST link. After syncing, Notehub reports the new firmware version and the device status back to your dashboard.

Compatibility and Limitations

• CircuitPython — Not supported on the Cygnet or CX. Attempts to port CircuitPython required dropping too many features to be practical.
• Toolchain support — Works with STM32CubeIDE and Arduino IDE. Existing Cygnet tutorials apply to the CX because it uses the same microcontroller family.
• MCP / Blues Expert — The CX is compatible with Blues Expert MCP tools for integration with large language models and other advanced flows.
• Documentation — A full datasheet is available.

Final Thoughts

The Notecarrier CX pulls together the convenience of Notecard/Notecarrier connectivity and the flexibility of an onboard STM32 host into one board. It's aimed at teams that want cleaner architectures, faster iteration, and a smoother path from prototype to production without sacrificing the ability to update host firmware remotely.

Whether you need a compact dev board to prove an idea or a solder-down friendly module for early production, the CX is built to simplify the design and accelerate what's possible when building with Blues.