https://test-devzone.nordicsemi.com/f/nordic-q-a/88664/sdk17-2-uart-no-logHello, SDK17.2,keil5, nRF21540-DK the uart can&#39;t log output, i&#39;ve no idea. PS: \nRF5_SDK_17.0.2_d674dde\examples\peripheral\uart\ can got uart log Best regardsen-USTelligent Community 13 Non-ProductionWed, 08 Jun 2022 00:22:42 GMThttps://test-devzone.nordicsemi.com/thread/371254?ContentTypeID=1Wed, 08 Jun 2022 00:22:42 GMT137ad170-7792-4731-bb38-c0d22fbe4515:ba0d51bc-b981-4ffb-9cbe-47341beb4a13user106325<p>thanks</p><div style="clear:both;"></div>https://test-devzone.nordicsemi.com/thread/371084?ContentTypeID=1Tue, 07 Jun 2022 09:21:03 GMT137ad170-7792-4731-bb38-c0d22fbe4515:ca283e2a-c0a4-4bb6-9f7d-a35abf0e6d8bHung Bui<p>Hi,&nbsp;</p> <p>Please check if you added retarget.c into your project.&nbsp;</p><div style="clear:both;"></div>