https://devzone.nordicsemi.com/f/nordic-q-a/32490/can-not-build-with-_vsprintf-sdk-v14-2stdio.h defines vsprintf and _vsprintf, and suggests using _vsprintf if you want to save on code space. extern _ARMABI int _vsprintf(char * __restrict /*s*/, const char * __restrict /*format*/, __va_list /*arg*/) __attribute__((__nonnull__(1,2))); en-USTelligent Community 13Mon, 19 Mar 2018 23:13:15 GMThttps://devzone.nordicsemi.com/thread/125068?ContentTypeID=1Mon, 19 Mar 2018 23:13:15 GMT137ad170-7792-4731-bb38-c0d22fbe4515:1553d474-2565-4cde-84f4-772db3b87030Keith Brafford<p>Thanks for your help.&nbsp; I&#39;ll give that a try.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/125067?ContentTypeID=1Mon, 19 Mar 2018 22:49:25 GMT137ad170-7792-4731-bb38-c0d22fbe4515:7d87755b-24d6-419d-a30c-0acf582779aaJeff4BLE<p>To use _vsprintf, the target option Use MicroLIB must be disabled. It is enabled by default. Disabling MicroLIB may reduce the code size a bit. However, RAM usage is likely to explode. I suggest considering&nbsp;<a href="http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.kui0099a/armlib_cihhegaa.htm">vsnprint</a>.&nbsp;<a href="http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.kui0099a/armlib_cihhegaa.htm"></a></p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/125038?ContentTypeID=1Mon, 19 Mar 2018 15:20:25 GMT137ad170-7792-4731-bb38-c0d22fbe4515:230a5284-4c5e-45f6-be6d-3a33794c06ddMartinBL<p>Hi,</p> <p>I&#39;ll ask around in the SDK team, although this doesn&#39;t seem Nordic related.&nbsp;</p><div style="clear:both;"></div>