Energy Aware RTOS for EFM32

Abstract

Power consumption is a major concern for portable or battery-operated devices.Recently, new low power consumption techniques have been used to achieveacceptable autonomy battery-powered systems. FreeRTOS is a real-time kernel designedespecially for embedded low-power MCUs. Energy Micro develops and sellsenergy friendly microcontrollers based on the industry leading ARM Cortex-M332-bit architecture. The aim of this thesis is to propose a new FreeRTOS TicklessFramework solution that exploits the power modes provided by EFM32. Three differentsolutions have been proposed, such as FreeRTOS RTC, FreeRTOS Ticklesswith prescaling and FreeRTOS Tickless without prescaling. The simulations showedthat the Tickless Framework saves energy from 15x to 44x more than Original versionof FreeRTOS. Using a self-made benchmark the battery (1500 mAh) lifetimehas been increased from 11 days to 487 days.