https://devzone.nordicsemi.com/f/nordic-q-a/19346/nrf51-dk-reboots-when-trying-to-connect-to-custom-board-with-needle-adapterI&#39;m having major troubles with my debugging setup using a nRF51 DK (PCA10028 V1.2.0). When I try to connect to the board I want to debug/program (which has an BlueMod +S = nRF51822), the nRF 51 DK seems to be rebooting (LED5 turns of for a second thenen-USTelligent Community 13Fri, 12 May 2017 08:28:37 GMThttps://devzone.nordicsemi.com/thread/75046?ContentTypeID=1Fri, 12 May 2017 08:28:37 GMT137ad170-7792-4731-bb38-c0d22fbe4515:bbc551b3-b661-4e05-9e41-6632b4faa392DerPMO<p>For the case that someone stumbles upon this question: It is possible to get the CPU into an unrecoverable state just by having some errors in your code (although I&#39;m still not sure what the cause is). My problem actually was that the battery is soldered to the board and I didn&#39;t have any way to do a hard reset (power cycling). After I disconnected and reconnected the battery, the &quot;bricked&quot; PCB worked again. I guess having a button to trigger the chip reset line also would do the trick.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/75045?ContentTypeID=1Wed, 01 Feb 2017 15:07:35 GMT137ad170-7792-4731-bb38-c0d22fbe4515:d22aeb5d-7a98-431d-a34c-69f6a9211c94FormerMember<p>One suggestion is to check if there is any short-circuits that aren&#39;t so easy to see on the board.</p><div style="clear:both;"></div>