https://devzone.nordicsemi.com/f/nordic-q-a/54310/modification-to-uart-central-example-creates-issuesHello, We made a small replacement on the event handler of the ble_central/ble_app_uart_c application, just to do a loopback to test the UART module. Here is how the hanlder looks now: /**@brief Function for handling app_uart events. * en-USTelligent Community 13Wed, 13 Nov 2019 15:35:01 GMThttps://devzone.nordicsemi.com/thread/219921?ContentTypeID=1Wed, 13 Nov 2019 15:35:01 GMT137ad170-7792-4731-bb38-c0d22fbe4515:58106d8e-cf48-41b1-9618-10986d3d04b2Edvin<p>Hello Jay,</p> <p>Have you tried debugging to see whether the&nbsp;<span>app_uart_put() is called, and what it returns? Or alternatively, do you see it in your log? (I see that you have a line that should print it out).</span></p> <p><span></span></p> <p><span>Best regards,</span></p> <p><span>Edvin</span></p><div style="clear:both;"></div>