https://devzone.nordicsemi.com/f/nordic-q-a/28312/where-to-put-app_timer_def-without-error-or-warningI am working on a project in Nordic SDK 8.1 that requires using a timer. I am confused where I need to define the timer though (using APP_TIMER_DEF). If I put it right after my #include statements I get the following error: ../../../main.c:39:1: warningen-USTelligent Community 13Thu, 14 Dec 2017 18:29:40 GMThttps://devzone.nordicsemi.com/thread/111788?ContentTypeID=1Thu, 14 Dec 2017 18:29:40 GMT137ad170-7792-4731-bb38-c0d22fbe4515:a0e99977-599e-4b6c-99c6-f6ded2acf226tyler<p>Ok thanks!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/111786?ContentTypeID=1Wed, 13 Dec 2017 10:27:36 GMT137ad170-7792-4731-bb38-c0d22fbe4515:de0ae8e3-e03e-4e13-b1f4-4bb18667709bMartinBL<p>Are you using the app_timer library from SDK 8.1 too? I can&#39;t find that macro in that version of the library. The correct way to do it there would be to declare <code>static app_timer_id_t m_battery_timer_id;</code> somewhere at the top of main.c (as it is done in e.g. the ble_app_hrs example).</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/111787?ContentTypeID=1Wed, 13 Dec 2017 09:27:31 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c3396759-334a-4559-a34e-bd2935df7cb8Jim<p>I do not know if my answer will help you, but I used it like this:</p> <p>int You_want_function(void) { APP_TIMER_DEF(m_timer_id); app_timer_create(&amp;m_timer_id, APP_TIMER_MODE_SINGLE_SHOT,timeout_handler); app_timer_start(m_timer_id, APP_TIMER_TICKS(5000, APP_TIMER_PRESCALER), NULL); }</p> <p>You can start as above in the some function you want to use.</p><div style="clear:both;"></div>