This is a (WIP!) Rust board support package for the open source Solo security key.
This key consists of: - an STM32L432KC microcontroller - either a USB-A or USB-C connector - a clicky dome button - 3 LEDs - an NCP114 voltage regulator - and various resistors, capacitors, and Zener diodes
One specialty is that it has a custom USB bootloader, allowing easy updates. Alternatively, the ST DFU bootloader can be used. Additionally, serial TX/RX and all SWD pins (SWDIO, SWCLK, SWO) are kind of broken out.