The MicroPython v1.28 release quietly brought official support for a compelling little microcontroller board: the WeAct STM32U585CIU6 Core Mini, a low-cost standalone board built around ST's STM32U585CIU6 Cortex-M33 MCU. While WeAct published schematics, 3D files, and code samples on their GitHub back in 2024, the MicroPython addition makes it the most accessible entry point yet for developers wanting to experiment with ST's power-efficient Armv8-M platform.
The board packs a respectable amount of capability into a 52.8 x 20.8 mm footprint. The STM32U585CIU6 runs an Arm Cortex-M33 core at up to 160 MHz with hardware FPU and Arm TrustZone security, 768 KB of SRAM, and 2 MB of onboard flash, plus a Chrom-ART 2D graphics accelerator (DMA2D). A footprint for external SPI flash (W25QxxJVSSIQ) is also present for projects that need more storage. Connectivity is handled by a single USB-C port for both power and programming, two 20-pin expansion headers exposing GPIO and power rails, and a 4-pin SWD debug header. The board ships with a preinstalled bootloader, meaning it works out of the box with the Arduino IDE or STM32CubeIDE without needing an ST-LINK.
User feedback confirms solid real-world compatibility, with buyers successfully running temperature-monitoring projects using external ADCs and testing basic demos via ST-LINK with no issues. With MicroPython now in the mix as a third programming option, the WeAct STM32U585CIU6 Core Mini is priced under $8 including shipping, making it a notably affordable way to get hands-on with the STM32U5 family.
