https://devzone.nordicsemi.com/f/nordic-q-a/13264/using-rtc-driver-with-softdeviceHi, i am trying to start a RTC0 on nrf52 DK with SoftDevice (s132) enabled with project based on &quot;ble_app_template&quot;. The problem is that a sd_softdevice_enable() (called in main -&gt; ble_stack_init() -&gt; SOFTDEVICE_HANDLER_INIT()) returns NRF_ERROR_INVALID_STATEen-USTelligent Community 13Sat, 16 Apr 2016 18:32:41 GMThttps://devzone.nordicsemi.com/thread/50570?ContentTypeID=1Sat, 16 Apr 2016 18:32:41 GMT137ad170-7792-4731-bb38-c0d22fbe4515:f6f844ed-0a4b-4c4d-b8c3-7bb08489af31Konstantin<p>Thanks for the fast reply.</p> <p>I&#39;ve already tried to use other RTC instances with same result. But now i think it is because my first attempt to use the RTC0 instance (i really forget this SoftDevice requirement, because i certainly know that RTC1 occupied by app_timer.c realization). I will try to use RTC2 again.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/50569?ContentTypeID=1Sat, 16 Apr 2016 11:13:56 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c63308b0-d463-4061-a636-d3ca0585e28aRK<p>You can&#39;t use RTC0, the softdevice uses it for its timing. See table 4, section 8.1 of the softdevice 132 specification to see what peripherals the softdevice claims for itself.</p> <p>So start by fixing your code to use a different RTC instance and see if you get any further.</p> <p>Also the documentation for NRF_ERROR_INVALID_STATE says that you get that when the softdevice is already enabled. So it is?</p><div style="clear:both;"></div>