CMSIS Version 5 Development Repository
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Latest commit 42f24ef Feb 20, 2017 @bn01Mra bn01Mra Fixed broken links

CMSIS Version 5

CMSIS Version 5.0.1 release is now available.

This GitHub repository development branch reflects our current state of development and is constantly updated.

The pre-built documentation is available under

Use Issues to provide feedback and report problems for CMSIS Version 5. Note that this repository gives our users and partners contiguous access to the CMSIS development. It allows you to review the work and provide feedback or create pull requests for contributions.

What's Hot

  • CMSIS-RTOS2: RTX 5 is now available for IAR, GCC, ARM Compiler 5, ARM Compiler 6
  • CMSIS-RTOS2: FreeRTOS adoption (beta) available in
  • CMSIS-Core: compiler agonstic features extended to simplify transition on LLVM based front-end
  • Coming soon: CMSIS-Core, CMSIS-RTOS2 for Cortex-A

Implemented Enhancements

  • Support for ARMv8-M Architecture (Mainline and Baseline) as well as devices Cortex-M23 and Cortex-M33

  • CMSIS-RTOS Version 2 API and RTX reference implementation with several enhancements:

    • Dynamic object creation, Flag events, C API, additional thread and timer functions
  • CMSIS-RTOS API Secure and Non-Secure support, multi-processor support

Futher Planned Enhancements

  • Improvements for Cortex-A / M hybrid devices (focus on Cortex-M interaction)

  • CMSIS-Pack

    • Additions for generic example, project templates, multiple download portals
    • Adoption of IAR Flash Loader technology

For further details see also the Slides of the Embedded World CMSIS Partner Meeting.

Directory Structure

Directory Content
CMSIS/Core CMSIS-Core related files (for release)
CMSIS/DAP CMSIS-DAP related files and examples
CMSIS/Driver CMSIS-Driver API headers and template files
CMSIS/DSP CMSIS-DSP related files
CMSIS/RTOS RTOS v1 related files (for Cortex-M)
CMSIS/RTOS2 RTOS v2 related files (for Cortex-M & ARMv8-M)
CMSIS/Pack CMSIS-Pack examples and tutorials
CMSIS/DoxyGen Source of the documentation
CMSIS/Utilities Utility programs

Generate CMSIS Pack for Release

This GitHub development repository contains already pre-build libraries of various libraries (DSP, RTOS, RTOS2). These libraries are validated for release.

To build a complete CMSIS pack for installation the following additional tools are required:

  • doxygen.exe Version: 1.8.6 (Documentation Generator)
  • mscgen.exe Version: 0.20 (Message Sequence Chart Converter)
  • 7z.exe (7-Zip) Version: 16.02 (File Archiver)

Using these tools, you can generate on a Windows PC:

  • CMSIS Software Pack using the batch file gen_pack.bat (located in ./CMSIS/Utilities). This batch file also generates the documentation.

  • CMSIS Documentation using the batch file genDoc.bat (located in ./CMSIS/Doxygen).

The file ./CMSIS/DoxyGen/How2Doc.txt describes the rules for creating API documentation.


ARM CMSIS is licensed under Apache-2.0.

Contributions and Pull Requests

Contributions are accepted under Apache-2.0. Only submit contributions where you have authored all of the code.