Q:

How can I make FreeRTOS energy friendly, by utilizing EM2 (Deep Sleep) in idle periods?



A:

The official FreeRTOS release uses the Systick timer and is therefore not able to go below EM1. However, a port has been made for the EFM32 which utilizes the RTC to keep time, hence being able to go to EM2 during idle periods:

http://www.freertos.org/index.html?http://interactive.freertos.org/entries/20291196-energy-optimized-port-of-freertos-6-for-efm32