https://devzone.nordicsemi.com/f/nordic-q-a/2676/how-to-debug-problem-related-to-led-blinkingHello all, I have flased &quot;ble_app_hts&quot; example for nrf51822 on evaluation board PCA10001. In the application both the LED pins are configured for output using &quot;nrf_gpio_cfg_output&quot;. Also for each event LED blinking is handled carefully. In advertising_starten-USTelligent Community 13Tue, 03 Jun 2014 16:53:29 GMThttps://devzone.nordicsemi.com/thread/10501?ContentTypeID=1Tue, 03 Jun 2014 16:53:29 GMT137ad170-7792-4731-bb38-c0d22fbe4515:d0173cd4-58ab-483b-b9dc-7c638d8f48c2sushil<p>Thanks a lot! Is there any good resource/doc for debugging nrf51822 application apart from eval-kit user guide and application note?</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/10500?ContentTypeID=1Tue, 03 Jun 2014 13:24:03 GMT137ad170-7792-4731-bb38-c0d22fbe4515:5055a7d6-ae61-4622-b4d1-37c6194f308bH&#229;kon Alseth<p>The ble_app_hts project is made for the nRF6310+nRF51x22 DK kit, so the GPIOs will not match the PCA10001 EV kit. Could you make sure that define &quot;BOARD_PCA10001&quot; (instead of &quot;BOARD_NRF6310&quot;) is defined in your Keil project? Should be under &quot;project settings -&gt; C/C++&quot; tab.</p><div style="clear:both;"></div>