Power management on embedded devices boils down to an amazingly  simple principle “turn-off anything you don’t use.” Though this sounds  fairly simple, the actual implementation can be quite complex. The Nucleus® real-time operating system attempts to minimize the complexity  by taking care of as many of the nitty-gritty details as possible,  allowing the software developer to make high-level decisions, but also  giving the developer the option of full control if desired.

The attached paper covers a few of the power management techniques that define  device static power consumption. Dynamic CPU power savings utilizing  CPU_Idle functionality and the automatic tick suppression feature  available in Nucleus will also be discussed. Lastly, the concept of  Dynamic Voltage and Frequency  Scaling (DVFS) will be covered as it  applies to both static and dynamic power savings. All of the discussed  techniques are analyzed when applied to the Atmel reference platform  AT91SAM9M10-EKES.

You can also see the power saving features in action on the Freescale i.MX28 evaluation board in the video below: