https://devzone.nordicsemi.com/f/nordic-q-a/85566/call-to-systeminit-requiredHi, I&#39;ve just returned to working on an nRF52811-based project after a year so I&#39;m a little rusty, and I&#39;m wondering if it is necessary to explicitly call SystemInit() (in system_nrf52811.c) in my main file? I&#39;ve not seen this done anywhere in the examplesen-USTelligent Community 13Tue, 08 Mar 2022 14:34:34 GMThttps://devzone.nordicsemi.com/thread/356933?ContentTypeID=1Tue, 08 Mar 2022 14:34:34 GMT137ad170-7792-4731-bb38-c0d22fbe4515:39b28ad3-2011-423e-b79a-f425d99f17a8Pete W<p>Ah, so it&#39;s called from inside the startup .s file. Thanks for the reply Vidar. I&#39;m using Eclipse with GCC but I can see the&nbsp;gcc_startup_nrf52811.S file in my makefile. And if I comment out the system_nrf52811.c file I get a compile error (can&#39;t find SystemInit() ), as expected.</p> <p>Thanks again.</p> <p>Pete</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/356906?ContentTypeID=1Tue, 08 Mar 2022 13:31:42 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c4c684be-a9e8-46ad-af98-ac5affcdbbe7Vidar Berg<p>Hi,</p> <p>SystemInit() should get called by your startup code before reaching main(). The call is made here if you use SES and the SDK provided startup files:</p> <p><img src="https://devzone.nordicsemi.com/resized-image/__size/320x240/__key/communityserver-discussions-components-files/4/pastedimage1646746255418v1.png" alt=" " /></p> <p>Best regards,</p> <p>Vidar</p><div style="clear:both;"></div>