Cesium RTOS Made for STM32

Approved for STM32-based Applications

Cesium RTOS is part of the STMicroelectronics extensive ecosystem and is approved for ST's MadeForSTM32 quality label. The MadeForSTM32 quality label is granted only after the completion of a thorough examination of the software development process and a rigorous functional hands-on review.

STMicroelectronics' MadeForSTM32 quality label honors outstanding solutions that meet the strictest standards for software usability, technical support, and product performance. It provides engineers confidence when locating software solutions for the STM32 microcontroller ecosystem that have met the highest level of quality married with simplified integration.

The downloadable I-CUBE-Cesium package incorporates Cesium RTOS (Cs/OS2 and Cs/OS3) into the STM32Cube extension package for ARM Cortex-M-based MCUs. This comprehensive and seamless integration gives you easy access to commercial-grade, professional embedded software right from within the highly popular STM32Cube environment.



Compatible with the STM32Cube ecosystem

 Supports all STM32 (ARMv7M and v8M) microcontrollers

 Compatible with all STM32 (ARMv7M and v8M) development boards

 Simple portability among various STM32 series MCU's thanks to the STM32Cube integration

 Available at no cost



Based on Weston Embedded Solutions' Cesium RTOS, I-CUBE-Cesium was created specifically for developers that require a complete development environment for STM32 microcontrollers. The I-CUBE-Cesium package can be downloaded here:



Step-by-step instructions on how to set up and use the I-CUBE-Cesium package can be found here:

Getting Started Guide

i cube cesium 1


Cesium software includes comprehensive documentation, full source code, powerful debugging features, and support for a huge range of CPU architectures.


Cesium software offers unprecedented ease-of-use, a small memory footprint, remarkable energy efficiency, and all with a full suite of protocol stacks.


Engineers across the world building industrial controls, medical devices, and aerospace systems know they can rely on Cesium software for the foundation of exceptional products.