https://devzone.nordicsemi.com/f/nordic-q-a/15330/unable-to-go-into-uart-interrupt-after-6-minutes-runningHello, I am using nrf51822 doing projects. I met an issuse which is that at the first 6 minutes, it can normaly go into UART interrupt and run subroutine successfully. But after 6 minutes running, it can not go into UART interrupt again. I use Keilen-USTelligent Community 13Wed, 03 Aug 2016 13:55:35 GMThttps://devzone.nordicsemi.com/thread/58590?ContentTypeID=1Wed, 03 Aug 2016 13:55:35 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b5ca84d0-f706-4725-85af-66cc2d8ca617Ole Bauck<p>Do you know where in the code you are &quot;stuck&quot;? Go into debug mode and stop the execution when you don&#39;t go into uart interrupt or main anymore.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/58593?ContentTypeID=1Wed, 03 Aug 2016 01:29:07 GMT137ad170-7792-4731-bb38-c0d22fbe4515:3f2f230c-1585-4d3f-aa5b-5871d220b8bbsunnyjet16<p>I masked some subroutines such as read external memory and key scan. I&#39;m not sure if subrountines causes this issue. I use a variable to test the uart interrupt. When enterring the subroutine, the variable will have an increment. When the variable stops increasing, it means it does not enter interrupt.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/58592?ContentTypeID=1Wed, 27 Jul 2016 08:41:55 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c61fc5fb-4e08-4e84-bcde-def8231eb099Ole Bauck<p>Which functions did you mask out? You are sure that the application is not hitting an error condition and freezes, see <a href="https://devzone.nordicsemi.com/question/60125/my-device-is-freezing-and-restarting/">here</a>?</p> <p>How do you check that the interrupt is not entered? Blinking a LED?</p> <p>System parameters do you mean the UART registers? You can see those if you are running the debugger and stops the code. The NRF_UART0-&gt;EVENTS_RXDRDY will be set when data is received on the UART, and if interrupt is enabled for this event (should be if you are to enter the interrupt when something is received) then when this is set you should enter the interrupt. You can use PPI to toggle a LED when this event happens.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/58591?ContentTypeID=1Wed, 27 Jul 2016 01:22:11 GMT137ad170-7792-4731-bb38-c0d22fbe4515:a9b345cb-3e48-4ab2-a68a-5eef39f416dbsunnyjet16<p>Hi Ole, I did not use sd_power_system_off(). Yesterday, I masked some functions and it can run continuously about 1 hours without issue. But after one hour, it can not enter mainloop and UART interrupt again. Is there any methods to oversee the system parameters? Regards Alex</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/58589?ContentTypeID=1Tue, 26 Jul 2016 09:40:44 GMT137ad170-7792-4731-bb38-c0d22fbe4515:cbe4004c-718e-4f08-8f18-24651df4b6e8Ole Bauck<p>Do you go to system OFF mode for example with <code>sd_power_system_off()</code>? The examples do this by default after 3 minutes (APP_ADV_TIMEOUT_IN_SECONDS).</p><div style="clear:both;"></div>