https://devzone.nordicsemi.com/f/nordic-q-a/41630/undefined-reference-to-nrf_drv_rng_initHi, I am using Segger IDE. I encounter error undefined reference to `nrf_drv_rng_init&#39; . I have include the below header file; #include &quot;nrf_drv_rng.h&quot; I already enable below macro; #ifndef RNG_ENABLED #define RNG_ENABLED 1 #endif #ifndefen-USTelligent Community 13Mon, 17 Dec 2018 01:57:57 GMThttps://devzone.nordicsemi.com/thread/161972?ContentTypeID=1Mon, 17 Dec 2018 01:57:57 GMT137ad170-7792-4731-bb38-c0d22fbe4515:95ace5f1-ddbc-4167-bf51-fc674565a466konsang<p>Hi,&nbsp;</p> <p>Yes. I am missing to add the legacy files.&nbsp;</p> <p>Thanks.&nbsp;</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/161967?ContentTypeID=1Sun, 16 Dec 2018 19:43:03 GMT137ad170-7792-4731-bb38-c0d22fbe4515:868177a6-aaf4-4781-8274-bef67b1f08abEinar Thorsrud<p>Hi,</p> <p>If the linker complains about undefined reference to it would seem like you are missing either the sdk_config.h macros (which you have already checked) or that you simply forgot to add &lt;SDK 15&gt;integration/nrfx/legacy/nrf_drv_rng.c to the project. Could that be it?</p><div style="clear:both;"></div>