https://devzone.nordicsemi.com/f/nordic-q-a/3560/question-about-ble-stackHello, I get a sample code in the dir flllowed after intsalling nRF51 SDK: \Keil\ARM\Device\Nordic\nrf51822\Board\pca10001\s110\ble_app_beacon_code\main.c but I still don&#39;t know how the BLE stack work after reading SDK document and the commenten-USTelligent Community 13Fri, 22 Aug 2014 01:20:28 GMThttps://devzone.nordicsemi.com/thread/12900?ContentTypeID=1Fri, 22 Aug 2014 01:20:28 GMT137ad170-7792-4731-bb38-c0d22fbe4515:2b15311c-6446-4e4c-adab-0ad384ecade7Ricky<p>thank you so much! :)</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/12899?ContentTypeID=1Thu, 21 Aug 2014 15:22:22 GMT137ad170-7792-4731-bb38-c0d22fbe4515:6a3b0de5-3c49-4b9b-8bea-fb6cd500754fNikita<p>To start advertising you need to call sd_ble_gap_adv_start() and to stop advetrising you need to call sd_ble_gap_adv_stop(). So when you push the button you need to call sd_ble_gap_adv_start() and when you release the button you need to call sd_ble_gap_adv_stop(). P.S. misclicked and converted your comment to answer by mistake.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/12898?ContentTypeID=1Thu, 21 Aug 2014 10:12:32 GMT137ad170-7792-4731-bb38-c0d22fbe4515:67b6d717-eadc-4b6e-a9f6-9ed69db45842Ricky<p>Thank you so much!</p> <p>Now I want to only broadcast when I push a button, how should I use the API ?</p> <p>I am new to the BLE stack, thank you again!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/12897?ContentTypeID=1Thu, 21 Aug 2014 09:38:51 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e3ea57bb-d39d-4d42-a1f0-d451c87bcf6cNikita<p>Regarding sd_app_evt_wait() you can read <a href="https://devzone.nordicsemi.com/documentation/nrf51/6.0.0/s110/html/a01004.html#ga11d88d38ac99fb72cde74c9385d36433">this</a>.</p> <p>sd_ble_gap_adv_start() is just signal to softdevice to start advertising with the specified by ble_advdata_set() (sd_ble_gap_adv_data_set()) data.</p><div style="clear:both;"></div>