https://devzone.nordicsemi.com/f/nordic-q-a/74104/unable-to-bring-up-zephyr-hci-uart-on-nrf5340dkI am testing HCI UART and HCI USB to use nRF5340DK as a Bluetooth Controller for RPI400 . While HCI USB is working well as expected, I have trouble bringing up HCI UART. Test setup Unmodified nRF5340DK is connected to RPI400&#39;s USB port via the interfaceen-USTelligent Community 13Tue, 20 Apr 2021 12:52:46 GMThttps://devzone.nordicsemi.com/thread/305859?ContentTypeID=1Tue, 20 Apr 2021 12:52:46 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c6e8ac65-0061-4e72-9c40-1e68968c593eJONATHAN LL<p>Hi,<br /><br />I dont think there is anything you are missing, following the procedure&nbsp;<a href="https://docs.zephyrproject.org/latest/samples/bluetooth/hci_uart/README.html">Bluetooth: HCI UART — Zephyr Project Documentation</a>&nbsp;here except building for 53 should work. Do you have a different Linux machine you can test on ?<br /><br />Regards,<br />Jonathan</p><div style="clear:both;"></div>