https://devzone.nordicsemi.com/f/nordic-q-a/94781/nrf52840-not-able-to-send-data-from-central-device-to-appHi Everyone, I am using nrf52840 in my project which is used as a central device. I have my app through which I can send data to the central device. The device is also able to receive the data and process it. Now when I want to send back the data toen-USTelligent Community 13Tue, 13 Dec 2022 11:53:29 GMThttps://devzone.nordicsemi.com/thread/400358?ContentTypeID=1Tue, 13 Dec 2022 11:53:29 GMT137ad170-7792-4731-bb38-c0d22fbe4515:41a7b3bd-c7ab-409f-bb4e-4e99884face3Simonr<p>Hi</p> <p>Are you sure that it is the&nbsp;<span>ble_aqrs_c_setting_send() function is what is trigging this hardfault specifically? I am assuming there is something with your custom service on the central side that is not set up correctly, but it&#39;s hard to tell by looking at your code what exactly it is. Are you certain the device is able to connect to and discover the correct service from the peripheral side? Do you see the data sent from the peripheral received correctly to the central application?</span></p> <p><span>Please check out<a href="https://devzone.nordicsemi.com/f/nordic-q-a/51016/custom-service-setup-in-central"> this reply </a>by my colleague Susheel here where he explains how to modify I.E. the ble_nus_c.c file to implement a custom central service to recognize a custom UUID and do discovery correctly, etc.</span></p> <p><span>Best regards,</span></p> <p><span>Simon</span></p><div style="clear:both;"></div>