// the take
A libmaple-based Arduino core for the original LeafLabs Maple and cheap generic STM32F103 boards, letting you write and flash sketches for a 72MHz Cortex-M3 chip through Arduino IDE 1.8.x. It's for people chasing the old "$2 Arduino with real peripherals" boards, not anyone starting a new STM32 project today.
Talks to the STM32F103 registers directly through libmaple rather than ST's HAL, so timers, DMA, ADC and USB CDC are implemented lean and fast instead of wrapped in HAL abstraction overhead. Ships a large pile of libraries already ported to the core (Adafruit GFX, SSD1306, ILI9341, etc.), so you're not the one fixing pin mappings and timer conflicts for every display library you want to use. Low barrier to entry if you already have Arduino sketches and just want them running on a Cortex-M3 board instead of an AVR.
The README itself says this is experimental and explicitly warns not to use it for anything critical — that's not boilerplate, the static-variable code-bloat issue listed in "Known issues" requires manually editing platform.txt, which is the kind of workaround you shouldn't still be hitting in a decade-old project. Hard-capped to the STM32F103 line and Arduino IDE 1.8.x; there's no path to F4/F7/H7 chips or Boards Manager-style installation, and the official stm32duino/Arduino_Core_STM32 (HAL-based, actively maintained, far broader chip support) has effectively superseded it. Because every peripheral is hand-ported into libmaple rather than generated from ST's chip definitions, extending support to a new variant is manual, slow work, not something that scales. No automated tests of library behavior — the CI just confirms things compile, so correctness is whatever the forum community has empirically found over the years.
We read the README, the directory tree and a key source file in October 2026. Nobody pays to be listed. How we judge →