https://devzone.nordicsemi.com/f/nordic-q-a/67922/there-seems-to-be-a-problem-connecting-bleHello I&#39;m testing the firmware using the BLE. When I upload, I can see that the board is working. Also, I don&#39;t think there&#39;s a problem with running each line of debugger. However, if connect the BLE in the nrf connect app, nothing comes out as shownen-USTelligent Community 13Tue, 03 Nov 2020 13:49:37 GMThttps://devzone.nordicsemi.com/thread/278286?ContentTypeID=1Tue, 03 Nov 2020 13:49:37 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e6d6ebc5-b747-43e0-9a7d-d226c3bcf274Simonr<p>Hi</p> <p>What does the debug log on the nRF side say? Seeing as the connection is terminated by the peer (nRF device) you should get an idea of what is happening by looking at the nRF debug log. If you don&#39;t see anything useful, make sure you&#39;ve set DEBUG in your preprocessor definitions to go into debug mode. If you&#39;re still struggling, please tell me which IDE you&#39;re using for development and some details as to what your device is supposed to do.</p> <p>Best regards,</p> <p>Simon</p><div style="clear:both;"></div>