https://devzone.nordicsemi.com/f/nordic-q-a/5828/undefined-symbol-ble_conn_paramsHello, I have taken the ble_app_beacon example and added a few things... I am looking to do something very simple like light up an LED on connection. So i added the on_ble_evt stuff from the NaN 36 example. Everything is working out except for the followingen-USTelligent Community 13Tue, 03 Mar 2015 00:03:57 GMThttps://devzone.nordicsemi.com/thread/20358?ContentTypeID=1Tue, 03 Mar 2015 00:03:57 GMT137ad170-7792-4731-bb38-c0d22fbe4515:21d9098d-8bb6-4fc9-874d-def140899636Greg Winn<p>Ok so i have solved my own issue here after looking at this question: <a href="https://devzone.nordicsemi.com/question/4881/fifo_apph/">https://devzone.nordicsemi.com/question/4881/fifo_apph/</a></p> <p>I needed to include the &#39;&quot;ble_conn_params.c&#39; file into my build</p> <p>In Keil</p> <ol> <li>Right click on &quot;Source Code&quot;</li> <li>Click &quot;Add existing file&quot;</li> <li>Find the ble_conn_params.c file under Source/ble</li> </ol> <p>Hope this helps some noob like myself!</p><div style="clear:both;"></div>