https://devzone.nordicsemi.com/f/nordic-q-a/104037/how-to-use-uart1-on-nrf9160-with-ns-buildIn order to be able to use uart1 as a hardware UART to talk to another microcontroller, w e defined pins for uart1 in an overlay file (and created a new build configuration so that the overlay file would be applied), and added this to our proj.conf (asen-USTelligent Community 13Fri, 22 Sep 2023 10:40:58 GMThttps://devzone.nordicsemi.com/thread/447226?ContentTypeID=1Fri, 22 Sep 2023 10:40:58 GMT137ad170-7792-4731-bb38-c0d22fbe4515:3a0c16da-8469-4c53-a8c2-14e9f72aff1cCharlie<p>Hi Michael,</p> <p></p> <p>Could you try to set the following configuration in prj.conf?</p> <p><pre class="ui-code" data-mode="text">CONFIG_TFM_SECURE_UART=n CONFIG_TFM_SECURE_UART1=n</pre></p> <p>Best regards,</p> <p>Charlie</p><div style="clear:both;"></div>