---
title: Introducing Blues Notecarrier CX - Carrier and Host MCU in One Board
description: Learn more about the new Notecarrier CX, featuring a user-addressable onboard STM32L433 MCU.
source_url: https://dev.blues.io/blog/introducing-notecarrier-cx/
canonical_url: https://dev.blues.io/blog/introducing-notecarrier-cx/
markdown_url: https://dev.blues.io/blog/introducing-notecarrier-cx.md
---

# Introducing Blues Notecarrier CX - Carrier and Host MCU in One Board

![Introducing Blues Notecarrier CX - Carrier and Host MCU in One Board banner](https://dev.blues.io/images/blog/posts/introducing-notecarrier-cx/banner.jpg?v=c80fc111)

January 27, 2026

## Learn more about the new Notecarrier CX, featuring a user-addressable onboard STM32L433 MCU.

- [Announcement](https://dev.blues.io/blog/tag/announcement)
- [Cygnet](https://dev.blues.io/blog/tag/cygnet)

[![Rob Lauer](https://dev.blues.io/images/blog/authors/rob-lauer.jpg?v=57fb21a7)](https://dev.blues.io/blog/author/rob-lauer/)

[Rob LauerSenior Director of Developer Relations](https://dev.blues.io/blog/author/rob-lauer/)

Today we're launching [Notecarrier CX](https://shop.blues.com/products/notecarrier-cx?utm_source=dev-blues\&utm_medium=web\&utm_campaign=store-link), a new member of the Blues Notecarrier family that's aimed squarely at embedded and IoT developers who desire reduced complexity while accelerating their prototype process.

**tl;dr Notecarrier CX is essentially a Notecarrier X combined with a Blues Cygnet in one board, available for only $17.50.**

You get the small, production-friendly Notecarrier X form factor, plus an onboard STM32 microcontroller as your host. One board instead of two, fewer wires, fewer decisions, and less setup before you're deploying real firmware.

| Front                                                                                                                          | Back                                                                                                                         |
| ------------------------------------------------------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------- |
| ![Notecarrier CX v1.3 (front)](https://dev.blues.io/images/blog/posts/introducing-notecarrier-cx/cx-front-vert.png?v=a4edb587) | ![Notecarrier CX v1.3 (back)](https://dev.blues.io/images/blog/posts/introducing-notecarrier-cx/cx-back-vert.png?v=6165aed9) |

> **Note:**
>
> Check out the [Notecarrier CX datasheet](https://dev.blues.io/datasheets/notecarrier-datasheet/notecarrier-cx-v1-7.md) for complete details, and use the [Blues Cygnet Quickstart](https://dev.blues.io/quickstart/cygnet-quickstart.md) to get started.

> **Note:**
>
> **This first version of Notecarrier CX is available as a BETA product.** See the [board errata section](https://dev.blues.io/datasheets/notecarrier-datasheet/notecarrier-cx-v1-3.md#board-errata) of the Notecarrier CX datasheet for details on known issues.

## Key Notecarrier CX Features

Let's take a quick run through some key features that make Notecarrier CX a standout development board.

### Onboard STM32L433 Host MCU

At the heart of Notecarrier CX is a **user-addressable STM32L433** (yes, that's the same MCU used on [Blues Cygnet](https://dev.blues.io/datasheets/cygnet-datasheet/cygnet-v1-2.md)), meaning you get:

- 80 MHz Cortex-M4
- 256 KB Flash
- 64 KB SRAM
- Ultra-low-power friendly design

To be clear, you can run your application directly on the board with no external host required. JTAG/SWD is available via an onboard debug jack, and BOOT/RST buttons are included for easy recovery and bootloader access.

### Small Form Factor

The board measures **76mm x 38mm**, with castellated edges that make it suitable for pick-and-place or solder-down use in production designs. It's compact enough to fit into real enclosures, not just on a lab bench.

![notecarrier cx dimensions](https://dev.blues.io/images/blog/posts/introducing-notecarrier-cx/cx-dimensions.jpg?v=f1cc24d9)

### USB-C for Power and Serial

A single **USB-C port** can power the board and provides a USB serial interface. A DIP switch lets you choose whether USB connects to the Notecard or the onboard STM32 host:

![dip switch on Notecarrier CX](https://dev.blues.io/images/quickstart/cygnet/cx-dip.jpg?v=9bc4224b)

### Qwiic Port for Peripherals

There's a **built-in Qwiic connector** for I2C peripherals. Plug in sensors, displays, or other modules without touching a breadboard. It's an easy way to prototype real applications quickly.

![notecarrier cx qwiic port](https://dev.blues.io/images/blog/posts/introducing-notecarrier-cx/cx-qwiic.jpg?v=6c7bb6f7)

### User Button and Essential I/O

*You also get:*

1. A programmable `USER_BTN`
2. Dual 16-pin headers exposing analog, digital, SPI, UART, and I2C
3. `AUX` diagnostic headers
4. `ATTN` and power control signals from the Notecard
5. A JST port for connecting a LiPo battery
6. An external SIM card slot for an optional Nano SIM

It's enough I/O to build serious prototypes without feeling constrained.

## One Board, Fewer Compromises

Notecarrier CX is a great fit if you are looking to build a small form factor device with an integrated host MCU. It's especially useful for teams validating ideas, building proof-of-concepts, or shipping early pilot runs.

By combining the Notecarrier X and Blues Cygnet into a single, compact board, Notecarrier CX removes a lot of the early-stage friction we all experience! You still get the flexibility of the Notecard ecosystem, but with a tighter, more integrated starting point.

And yes, [Notecarrier CX is available now!](https://shop.blues.com/products/notecarrier-cx?utm_source=dev-blues\&utm_medium=web\&utm_campaign=store-link) If you've been looking for a clean way to build Notecard-based systems, this might just be the board you've been waiting for.

Happy Hacking 💙