Keil Logo


The Cortex Microcontroller Software Interface Standard (CMSIS) provides a single standard across all Cortex-M processor series vendors. It enables code re-use and code sharing across software projects and reduces development time for new embedded applications. A detailed description can be found in the CMSIS Introduction.

CMSIS provides a common approach to interface peripherals, real-time operating systems, and middleware components across all silicon vendor products.

You can make use of the advantages offered through CMSIS and set configuration options by using the provided system_family name.c and RTE_Device.h files.

You can:

  1. Define interrupt and exception vectors.
  2. Initialize the external bus controller.
  3. Configure the CPU clock source.
  4. Copy the exception vectors from ROM to RAM for systems with memory remapping.
  5. Initialize other low level peripherals.

Some files have Configuration Wizard annotations and display a GUI-like interface to set options.

  1. Open the file in the Editor Window. Two tabs are displayed at the bottom: Text Editor and Configuration Wizard.

    Cortex System File

  2. Click on a value to change the content.
  Arm logo
Important information

This site uses cookies to store information on your computer. By continuing to use our site, you consent to our cookies.

Change Settings

Privacy Policy Update

Arm’s Privacy Policy has been updated. By continuing to use our site, you consent to Arm’s Privacy Policy. Please review our Privacy Policy to learn more about our collection, use and transfers
of your data.