Overview

CMSIS-CORE implements the basic run-time system for a Cortex-M device and gives the user access to the processor core and the device peripherals. In detail it defines:

• Hardware Abstraction Layer (HAL) for Cortex-M processor registers with standardized definitions for the SysTick, NVIC, System Control Block registers, MPU registers, FPU registers, and core access functions.
• System exception names to interface to system exceptions without having compatibility issues.
• Methods to organize header files that makes it easy to learn new Cortex-M microcontroller products and improve software portability. This includes naming conventions for device-specific interrupts.
• Methods for system initialization to be used by each MCU vendor. For example, the standardized SystemInit() function is essential for configuring the clock system of the device.
• Intrinsic functions used to generate CPU instructions that are not supported by standard C functions.
• A variable to determine the system clock frequency which simplifies the setup the SysTick timer.

The following sections provide details about the CMSIS-CORE:

• Using CMSIS in Embedded Applications describes the project setup and shows a simple program example.
• Template Files describes the files of the CMSIS-CORE in detail and explains how to adapt template files provided by ARM to silicon vendor devices.
• MISRA-C:2004 Compliance Exceptions describes the violations to the MISRA standard.
• Reference describe the features and functions of the Device Header File <device.h> in detail.
• Data Structures describe the data structures of the Device Header File <device.h> in detail.

---

CMSIS-CORE in ARM::CMSIS Pack

Files relevant to CMSIS-CORE are present in the following ARM::CMSIS directories:

File/Folder	Content
CMSIS\Documentation\Core	This documentation
CMSIS\Include	CMSIS-CORE header files (for example core_cm3.h, core_cmInstr.h, etc.)
Device	ARM reference implementations of Cortex-M devices
Device\_Template_Vendor	Template Files for extension by silicon vendors

---

Cortex-M Reference Manuals

The Cortex-M Reference Manuals are generic user guides for devices that implement the various ARM Cortex-M processors. These manuals contain the programmers model and detailed information about the core peripherals.

• Cortex-M0 Devices Generic User Guide
• Cortex-M0+ Devices Generic User Guide
• Cortex-M3 Devices Generic User Guide
• Cortex-M4 Devices Generic User Guide
• Cortex-M7 Devices Generic User Guide

---

Tested and Verified Toolchains

The CMSIS-CORE Template Files supplied by ARM have been tested and verified with the following toolchains:

• ARM: MDK-ARM Version 5.16
• GNU: GNU Tools ARM Embedded 4.9 2015.q2
• IAR: IAR Embedded Workbench Kickstart Edition V6.10

---