https://devzone.nordicsemi.com/f/nordic-q-a/106255/nrf52811---reducing-consumption-by-turning-hfclock-offHi I am exactly following the ESB TX example. All I need is to turn off the HFCLOCK after each transmission (believing that I reduce consumption to a minimum). I use Zephyr and my goal is to periodically transmit one packet every second. I have a SWen-USTelligent Community 13Thu, 07 Dec 2023 08:23:39 GMThttps://devzone.nordicsemi.com/thread/459289?ContentTypeID=1Thu, 07 Dec 2023 08:23:39 GMT137ad170-7792-4731-bb38-c0d22fbe4515:bca618a2-1d5c-4725-9151-3a2ad0f77aa1witc<p>duplicated: answer should be there soon: <a href="https://devzone.nordicsemi.com/f/nordic-q-a/105569/how-do-i-turn-off-the-clock-for-rf-clock_control_nrf_subsys_hf">devzone.nordicsemi.com/.../how-do-i-turn-off-the-clock-for-rf-clock_control_nrf_subsys_hf</a></p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/458493?ContentTypeID=1Fri, 01 Dec 2023 11:48:18 GMT137ad170-7792-4731-bb38-c0d22fbe4515:739d5bb3-ff08-4c09-8f57-5994f0bb7c1bwitc<p>Thank you, you can delete this one.&nbsp;<br /><span>Anyway, I definitely don&#39;t understand why the software timer doesn&#39;t expire (doesn&#39;t call the callback) - it only works when I&#39;m connected via JLINK and monitoring RTT outputs.</span></p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/458490?ContentTypeID=1Fri, 01 Dec 2023 11:45:18 GMT137ad170-7792-4731-bb38-c0d22fbe4515:74773147-003f-4e94-8a8d-02ae51ab7a68Hung Bui<p>Hi Witc,&nbsp;</p> <p>You are right about</p> [quote user=""]HFCLK RC is needed as a source for CPU operation and cannot be turned off, [/quote] <p>The CPU needs the HFCLK to run. You can turn off the HFCLK and put CPU to sleep, keeping only the RTC running to wake it up.&nbsp;<br />Anyway, please continue on the ticket with&nbsp;Naeem Maroof. I don&#39;t see why you want to create a new ticket for the same question.&nbsp;</p><div style="clear:both;"></div>