The author of this guide (Jorge Aparicio) has done an amazing amout of work getting the ecosystem started for Rust on microcontrollers. A few of his other projects worth mentioning:

- svd2rust (https://docs.rs/svd2rust/) generates register-level APIs from SVD files, an XML format provided by most ARM microcontroller vendors. This gets you the equivalent of the low-level C header files for manipulating the hardware registers.

- cortex_m (https://docs.rs/cortex-m/), which provides APIs for the core ARM peripherals in every Cortex-M MCU.

- f3 (https://docs.rs/f3/) - High level APIs for the peripherals and external sensors on the STM32 F3 Discovery board.