https://devzone.nordicsemi.com/f/nordic-q-a/42202/timer-issueHi, I am using &quot;ble_app_uart&quot; code and added battery service to it as custom changes. I want to update battery level at every 3 seconds. Code is working fine and starts broadcast &amp; advertise and service information but when I call/enable timer_initen-USTelligent Community 13Tue, 08 Jan 2019 05:52:46 GMThttps://devzone.nordicsemi.com/thread/164409?ContentTypeID=1Tue, 08 Jan 2019 05:52:46 GMT137ad170-7792-4731-bb38-c0d22fbe4515:a36e4d1d-eed1-4890-ad8b-ea6b0dc0196esachin.singh<p>Hi picben,&nbsp;</p> <p>Thank You So Much it Works ...!!!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/164222?ContentTypeID=1Mon, 07 Jan 2019 11:43:48 GMT137ad170-7792-4731-bb38-c0d22fbe4515:13698e90-ac04-498f-8fff-ca1059955cadpicben<p>Hi,</p> <p>I think you need to define your timer instance using the APP_TIMER_DEF macro. It will statically allocate some data block along with the app_timer_id_t object. You can try replacing&nbsp;the timer definition</p> <p>&nbsp;<pre class="ui-code" data-mode="c_cpp">static app_timer_id_t m_battery_timer_id;</pre></p> <p>by:</p> <p><pre class="ui-code" data-mode="c_cpp">APP_TIMER_DEF(m_battery_timer_id);</pre></p> <p>and see if it helps.</p><div style="clear:both;"></div>