https://devzone.nordicsemi.com/f/nordic-q-a/92051/how-to-know-if-you-re-flashing-an-external-board-with-nrf52840dkIs there a way of visually verifying if you&#39;re programming an external board with the nRF52840DK? Sometimes I&#39;m not sure if the pins are wired up correctly, in which case it would program the on-board nRF52840 instead.en-USTelligent Community 13Fri, 16 Sep 2022 14:38:31 GMThttps://devzone.nordicsemi.com/thread/386690?ContentTypeID=1Fri, 16 Sep 2022 14:38:31 GMT137ad170-7792-4731-bb38-c0d22fbe4515:942ceb1e-8b3c-4ecb-bf30-77238924fbaagendor<p>Thank you, that&#39;s very helpful!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/386688?ContentTypeID=1Fri, 16 Sep 2022 14:15:12 GMT137ad170-7792-4731-bb38-c0d22fbe4515:ee8ff4a2-a05b-4f8b-8bfe-96492244785fEinar Thorsrud<p>A quite simple way is to read the DEVICEID[0] register from FICR, as this is&nbsp;unique for each device. When nothing is connected to the debug out port, you should read the number of the onboard nRF on the DK. When an&nbsp;external device is connected, you should see a different number (which is different for each external device).</p> <p></p> <p>You can read it like this:</p> <p><pre class="ui-code" data-mode="text">nrfjprog --memrd 0x10000060</pre></p> <p>(if you are paranoid you can read&nbsp;DEVICEID[1] as well, which is at&nbsp;0x10000064, but that is probably overkill for this purpose)</p><div style="clear:both;"></div>