SAM C21 Systick Overview

The SAM C21 ARM® Cortex®-M0+ Processor Core includes an optional System Timer Module (SysTick) that provides a simple, 24-bit clear-on-write, decrementing, wrap-on-zero counter with a flexible control mechanism.


This hardware may be configured to periodically generate an interrupt and trigger the following handler routine:

void SysTick_Handler(void){

 Learn More

SysTick Configuration
Learn more >
SysTick Example Project
Learn more >

The SysTick operation is specified in Section B3.3 of the "ARM®v6-M Architecture Reference Manual."

© 2024 Microchip Technology, Inc.
Notice: ARM and Cortex are the registered trademarks of ARM Limited in the EU and other countries.
Information contained on this site regarding device applications and the like is provided only for your convenience and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. MICROCHIP MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR OTHERWISE, RELATED TO THE INFORMATION, INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, PERFORMANCE, MERCHANTABILITY OR FITNESS FOR PURPOSE. Microchip disclaims all liability arising from this information and its use. Use of Microchip devices in life support and/or safety applications is entirely at the buyer's risk, and the buyer agrees to defend, indemnify and hold harmless Microchip from any and all damages, claims, suits, or expenses resulting from such use. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual property rights.