// the take
An Arduino core that lets you write and flash sketches for STM32 microcontrollers in Arduino IDE 2.x, covering nearly every STM32 family from the F0 to the H7 and the newer U5/WB0/WL3 parts. It's for embedded developers who want Arduino's workflow and library ecosystem on ST silicon instead of bare STM32CubeIDE or Mbed.
The board coverage is the real draw — dozens of STM32 series and hundreds of board variants, each with its own pin maps and peripheral config, kept in sync via a CI build matrix rather than hand-maintained. It doesn't hide ST's HAL and LL layers behind the Arduino API; you can drop to register-level or LL calls when the abstraction is too slow or too limited, which matters a lot on constrained MCUs. There's also a parallel CMake build system and PlatformIO support alongside the Boards Manager path, so you're not locked into Arduino IDE if you outgrow it.
Arduino IDE 1.x support was dropped at 2.8.0, so anyone on the older toolchain is stuck on a stale release. New silicon support lags behind ST's own SDK releases and ships as hand-rolled patches against upstream HAL/CMSIS (see the WB0/WL3 patch files) — that's a manual sync point that can drift or break when ST changes its packages. Support is split between GitHub issues and a separate stm32duino.com forum, so there's no single place to search prior art before filing something. And the Arduino abstraction itself still costs you timing precision and flash/RAM headroom versus writing directly against HAL/LL, which is the usual tradeoff with Arduino cores on resource-constrained parts.
We read the README, the directory tree and a key source file in October 2026. Nobody pays to be listed. How we judge →