$3.40 WeAct STM32WB55 board offers Bluetooth LE 5.4 and 802.15.4 (Thread/Zigbee/Matter) connectivity

WeAct STM32WB55 is an inexpensive development board based on STMicro STM32WB55 Arm Cortex-M4 wireless SoC with Bluetooth LE 5.4 and an 802.15.4 radio for Zigbee, Thread, and Matter connectivity that sells for just $3.40 shipped.

STMicro STM32WB55 wireless microcontroller was introduced in 2019, and we have covered a few development boards such as the official P-Nucleo-WB55 development pack, the STM32WB-Feather board, and the MRK-SharkyPro following the Arduino MRK form factor. All those boards would go for about $40, but thanks to China manufacturing and procurement “magic” and the cutting of a few features, the WeAct STM32WB55 board sells for just a fraction of the price making it even cheaper than the company’s ESP32-H2 board with similar connectivity options.

WeAct STM32WB55 specifications:

Wireless MCU – STMicro STM32WB55CGU6
- CPU
  - Arm Cortex-M4 application core @ 64 MHz
  - Arm Cortex-M0+ Bluetooth co-processor @ 32 MHz
  - Memory – 256 KB of SRAM
  - Storage – 1 MB Flash storage
  - Connectivity
    - Bluetooth LE 5.4
    - 802.15.4 radio for Zigbee, Thread, Matter
Antenna – PCB antenna
USB – USB Type-C port for power and programming
Expansion – 20-pin + 15-pin headers with GPIOs, 10x analog input pins, USART, I2C, SPI, 5V, 3.3V, GND
Debugging – 4-pin SWD debug connector
Misc – NRST and BOOT0 buttons, user LED, 32MHz crystal
Power Supply – 5V via USB Type-C port
Dimensions – 56.06 x 21.08 mm

As usual, WeAct will bring the bare minimum documentation on GitHub with PDF schematics and step files, the STM32WB55 microcontroller datasheet, and a Bluetooth LE code sample. For more details about software development, you’d have to look at the documentation and resources for the P-Nucleo-WB55 or other boards.

The main strength of WeAct Studio is not software, but delivering ultra-low-cost hardware, and they’ve done a decent job on that front again…

Jean-Luc Aufranc (CNXSoft)

Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.