uart

  A bare metal programming guide (ARM microcontrollers)

  A serial device I/O tool

  USB to 3 Port Serial (UART) adapter firmware for STM32 Blue Pill.

翻译 - 用于STM32 Blue Pill的USB转3端口串行（UART）适配器固件。

  MFRC522 full function driver library for general MCU and Linux.