CMSIS-FreeRTOS  Version 10.3.1
CMSIS-RTOS2 compliant FreeRTOS Implementation
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FreeRTOS is one of the market leading real-time operating systems (RTOS) for embedded microcontrollers. It is professionally developed, strictly quality controlled, robust, supported, free to use in commercial products without a requirement to expose proprietary source code, and has no IP infringement risk.

CMSIS-RTOS v2 is a common API for real-time operating systems (RTOS). It provides a standardized programming interface that is portable to many RTOS and enables software components that can work across multiple RTOS systems. It supports the Armv8-M architecture, dynamic object creation, for multi-core systems, and has a binary compatible interface across ABI compliant compilers.

Using this software pack, users can choose between a native FreeRTOS implementation or one that is adhering to the CMSIS-RTOS2 API and using FreeRTOS under the hood. The CMSIS-RTOS2 API enables programmers to create portable application code to be used with different RTOS kernels (for example Keil RTX5).

This documentation shows you:


The CMSIS-FreeRTOS implementation is provided free of charge by Arm under the FreeRTOS license.


The ARM::CMSIS-FreeRTOS pack contains the following:

File/Directory Content
ARM.CMSIS-FreeRTOS.pdsc Package description file in CMSIS-Pack format.
License FreeRTOS license agreement.
CMSIS CMSIS-RTOS2 compliant implementation of FreeRTOS.
Config FreeRTOS configuration header file.
Demo FreeRTOS demo projects.
Documentation This documentation.
DoxyGen Source of the documentation.
Source FreeRTOS source code.
Utilities Utilities to build the pack.