https://devzone.nordicsemi.com/f/nordic-q-a/16934/nrf52-rtc-issueI&#39;m using the nRF52-DK (SDK11.0.0+s132) and added in some example code from the RTC example (the RTC2 tick interrupt with prescaler=0 to toggle a GPIO) to the ble_hrs example. It mostly interrupts every with a 32.768kHz tick (GPIO mostly pin has 61usen-USTelligent Community 13Sat, 08 Oct 2016 17:07:18 GMThttps://devzone.nordicsemi.com/thread/64908?ContentTypeID=1Sat, 08 Oct 2016 17:07:18 GMT137ad170-7792-4731-bb38-c0d22fbe4515:5ca9c9af-e5cf-4948-a805-e1789685eb7dTosa<p>thanks RK! (converted comment to answer below)</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/64909?ContentTypeID=1Sat, 08 Oct 2016 04:17:42 GMT137ad170-7792-4731-bb38-c0d22fbe4515:a524f33f-6b18-4bd9-a573-f507a2ecafedRK<p>Are you using an interrupt handler for this and do you have the softdevice running and advertising? If so it&#39;s just not going to work, there are many threads every week about this, the softdevice has a higher interrupt priority than your timer so it will interrupt it and delay your handler.</p> <p>You need to use PPI or the PWM module to generate accurate timing with the softdevice running, you cannot do it with interrupt handlers.</p><div style="clear:both;"></div>