This repository is cloned from ARM Limited, strictly compatible. It provides a subset of the CMSIS_5/CMSIS directory, providing a standardized set of header files, startup code, and core access functions that enable initialization, configuration, and control of ARM Cortex processor features.
Note
Some subdirectories like ./CMSIS/DAP or ./CMSIS/DoxyGen have been discarded as not used in the STM32Cube firmware. The ./CMSIS/Driver subdirectory has also been discarded as it should be replaced by a ../STM32XXxx_HAL_Driver directory in the complete file tree of a firmware.
Note
Starting from version 5.1.0, a Core_A/Include directory has been introduced to support Cortex-A cores. However, this has no impact on Cortex-M-based user applications.
Important
Starting from version 5.8.0, Arm removed the precompiled DSP libraries from the ./DSP/Lib subdirectory and moved them to this dedicated repository.
Important
During the successive deliveries from ARM Limited, an update has been introduced with version 5.0. A break of directory tree compatibility has been introduced: the files under the ./Include directory have been moved to anoter directory, ./Core/Include.
In order to preserve backward compatibility, the cmsis_core repository provided by STMicroelectronics introduces an ./Include directory at its root, where there is a copy of the content of the ./Core/Include directory provided by ARM.
Tip
With each official tag (e.g., v4.5), specific flavors of the CMSIS Core are proposed, one for each supported Cortex-M core. Each specific flavor is identified by a tag suffixed _cmX (e.g., tag v4.5_cm3 refers to version 4.5.0 of the CMSIS Core specific to Cortex-M3).
These specific flavors are size-optimized as their ./DSP/Lib subdirectory, the most voluminous, only contains the precompiled libraries for the intended Cortex-M core, those for other Cortex-M cores being removed.
All tags suffixed the same are part of a dedicated branch (e.g., v4.5_cm3, v5.4.0_cm3, v5.6.0_cm3 are part of the cm3 branch).
Please refer to the release note in the firmware repository for the STM32 series you are using (see the list in the STM32Cube MCU Offer). It is important to use a consistent set of software component versions as specified in the release note.
Please refer to the CONTRIBUTING.md guide.