https://devzone.nordicsemi.com/f/nordic-q-a/115600/direct-test-mode-not-connecting-to-custom-board-deviceWe built a custom version of the Direct Test Mode sample in our firmware, using the USB shell to interface with the test operations and removing the UART or HCI interface code, essentially all the code in the `transport` folder. Instead we run our ownen-USTelligent Community 13Fri, 18 Oct 2024 11:37:53 GMThttps://devzone.nordicsemi.com/thread/506887?ContentTypeID=1Fri, 18 Oct 2024 11:37:53 GMT137ad170-7792-4731-bb38-c0d22fbe4515:8ab47d8e-02cc-4dda-bf88-65aa26662e03Simonr<p>Hi</p> <p>What modifications have you made to the DTM sample exactly that might have caused this? Do you have an nRF5340 DK to test that you&#39;re able to use the DTM application with in the first place? You could also turn on Verbose logging, and upload it here so we could review the log to see if there&#39;s anything from the log that can tell us what&#39;s wrong here as I don&#39;t think this should be a problem.</p> <p><img style="max-height:240px;max-width:320px;" src="https://devzone.nordicsemi.com/resized-image/__size/640x480/__key/communityserver-discussions-components-files/4/pastedimage1729251379499v1.png" alt=" " /></p> <p>Alternatively, you could also try using another means of doing the DTM testing as per the <a href="https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/samples/bluetooth/direct_test_mode/README.html">Testing section of the sample documentation</a>. Either using a certified tested, another Development Kit or a terminal connection are options to test DTM too.</p> <p>Best regards,</p> <p>Simon</p><div style="clear:both;"></div>