ChibiOS  21.6.0
Giovanni Di Sirio (

Chibi ?

I didn't want a serious name for this project. It is the Japanese word for small as in small child. So ChibiOS (ちびOS) means small Operating System. Source Wikipedia.


ChibiOS is composed by several subsystems that are part of the project or external software components.


  • RT, a full features RTOS.
  • NIL, another RTOS with a very reduced footprint.
  • OSLIB, a library of RTOS enhancements, it can be used on top of both RT and NIL.
  • HAL, an abstraction layer for common MCU peripherals.
  • EX, abstraction for board-level devices, it sits on top of HAL.

External Components

  • FatFS.
  • lwIP.
  • WolfSSL.