<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Hi Bernard,<div class=""><br class=""></div><div class="">I have created two examples that leverages the low-power modes of the EFM32 MCU that I am working on.</div><div class=""><br class=""></div><div class="">Although this example is still very hardware dependent (because it is device-specific that the RTT can wakeup the MCU from sleep), I can get it down to 10µA in sleep (without other optimizations) with a wakeup time of ~2µs.</div><div class=""><br class=""></div><div class="">If you are interested, see <a href="https://github.com/basilfx/EFM2Riot/blob/master/dist/examples/sleep_wakeup/main.c" class="">https://github.com/basilfx/EFM2Riot/blob/master/dist/examples/sleep_wakeup/main.c</a>, <a href="https://github.com/basilfx/EFM2Riot/blob/master/dist/examples/sleep_wakeup_measure/main.c" class="">https://github.com/basilfx/EFM2Riot/blob/master/dist/examples/sleep_wakeup_measure/main.c</a> and probably <a href="https://github.com/basilfx/EFM2Riot/blob/master/dist/cpu/efm32_common/lpm_arch.c" class="">https://github.com/basilfx/EFM2Riot/blob/master/dist/cpu/efm32_common/lpm_arch.c</a> too.</div><div class=""><br class=""></div><div class="">Kind regards,</div><div class="">Bas</div><div class=""><br class=""><div><blockquote type="cite" class=""><div class="">Op 4 jun. 2016, om 14:15 heeft Bernhard Nägele <<a href="mailto:bernhard@naegele-privat.de" class="">bernhard@naegele-privat.de</a>> het volgende geschreven:</div><br class="Apple-interchange-newline"><div class=""><div class="">Hello RIOT-enthusiasts,<br class="">I'm searching for a good way to bring a RIOT-system to lowest power modes for several minutes.<br class="">As far as I understand the function of the xtimer is designed to provide the<br class="">timebase for thread/task switching and providing short low-power-delays.<br class="">It is therefore not designed to support slow clock timers inside low-power microcontrollers.<br class="">Is this true?<br class="">Can you give tell me your opinion about using the slow-clock timer simply inside<br class="">the application? The idea is to bring the peripherals to lowest power mode, then<br class="">stop all threads except the main thread, mask interrupts und stop then the<br class="">microcontroller under the control of the application. The wakeup could happen<br class="">by using an interrupt from the slow-clock-timer inside the CPU.<br class=""><br class="">Is this a way which could work?<br class=""><br class="">Best regards,<br class="">Bernhard<br class="">_______________________________________________<br class="">devel mailing list<br class=""><a href="mailto:devel@riot-os.org" class="">devel@riot-os.org</a><br class="">https://lists.riot-os.org/mailman/listinfo/devel<br class=""></div></div></blockquote></div><br class=""></div></body></html>