# cmsis_core

**Repository Path**: mirrors_STMicroelectronics/cmsis_core

## Basic Information

- **Project Name**: cmsis_core
- **Description**: CMSIS Core module, fully aligned with ARM versions.
- **Primary Language**: Unknown
- **License**: Apache-2.0
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 1
- **Forks**: 0
- **Created**: 2020-08-18
- **Last Updated**: 2026-01-10

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# STM32Cube CMSIS Core Interface MCU Software Component

![latest tag](https://img.shields.io/github/v/tag/STMicroelectronics/cmsis-core.svg?color=brightgreen)

> [!NOTE]
> The **cmsis_core** repository is delivered to STM32 users. It is **cloned** from ARM Limited, strictly compatible. 

## Overview of the STM32Cube MCU offer on GitHub

**STM32Cube** is an original initiative by STMicroelectronics to **simplify** prototyping and development by **reducing** effort, time, and cost. It supports the entire ARM™ Cortex-based STM32 microcontroller portfolio and provides a **comprehensive** software solution including:
  * The CMSIS Core and Device interfaces enabling access to processor core features and device-specific peripherals of STM32 microcontrollers.
  * The STM32 HAL-LL drivers, an abstraction layer offering a set of APIs ensuring maximized portability across the STM32 portfolio.
  * The BSP drivers enabling access to peripherals on the STM32 development boards, external to the microcontroller itself.
  * A consistent set of middleware libraries offering standardized, high-level functionalities — such as USB, TCP/IP, file systems, and graphics.
  * A full set of software projects (basic examples, applications, and demonstrations) that showcase specific functionalities or use cases, and provided with support for multiple IDEs.

The **STM32Cube embedded software** is available in two flavors:
  * The **MCU Firmware** _monolithic_ offer, where **all** software components (Drivers, Middleware, Projects, Utilities) are included in a **single** repository for each STM32 series.
  * The **MCU Software Components** _modular_ offer, where **each** software component (mainly Drivers and Middleware) is provided in a **dedicated** repository, allowing users to **select** only the components they need.

The complete list of repositories is available [here](https://github.com/STMicroelectronics/STM32Cube_MCU_Overall_Offer/blob/master/README.md#content).

## Repository content
   
This repository is a **subset** of the [CMSIS_5/CMSIS](https://github.com/ARM-software/CMSIS_5/tree/develop/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](https://github.com/ARM-software/CMSIS-DSP) 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 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).

## Release note

Details about the content of this release are available in the release note [here](https://github.com/STMicroelectronics/cmsis-core/blob/master/st_readme.txt).

## Compatibility information

Please refer to the **release note** in the firmware repository for the STM32 series you are using ([list](https://github.com/STMicroelectronics/STM32Cube_MCU_Overall_Offer/blob/master/README.md#stm32cube-mcu-packages)). It is **important** to use a **consistent set** of software component versions (i.e., CMSIS, HAL-LL, BSP, MW) as specified in the release note.

## Feedback and contributions

Please refer to the [CONTRIBUTING.md](CONTRIBUTING.md) guide.