https://devzone.nordicsemi.com/f/nordic-q-a/19166/mynewt-os-app-running-on-nrf51822-without-jlink-openocdA little background and what works: I&#39;m already familiar with using SD110 and SD130 APIs on the nRF51 series, so thats not an issue, also it confirms that my boards are working (so no hardware problems); I&#39;m using only GDB to upload my hex filesen-USTelligent Community 13Mon, 10 Apr 2017 20:33:25 GMThttps://devzone.nordicsemi.com/thread/74187?ContentTypeID=1Mon, 10 Apr 2017 20:33:25 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c9d2c655-deb4-49e0-80bc-083f4755e3b0sidekick<p>&quot;<em>I speculate that it could be something about the mynewt bootloader not beeing able to find the app flash address... or the mynewt bootloader trying to verify some app header signature/hash that does not exist and then exiting&quot;</em> - Yes indeed. The <code>newt create-image</code> command (which you are skipping), adds a magic number (<strong>0x96f3b83c</strong>) to the image and is checked by the mynewt bootloader. More information <a href="https://mynewt.apache.org/latest/os/modules/bootloader/bootloader/">here.</a></p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/74186?ContentTypeID=1Wed, 25 Jan 2017 06:46:18 GMT137ad170-7792-4731-bb38-c0d22fbe4515:f35f8712-ff00-41ce-b672-0c7fab094103Roger Clark<p>I think you need to give more information on your build process.</p> <p>Surely the build for mynewt ends up with a binary file, which JLink then uploads</p> <p>The upload address for all applications is the same (for the same SD)</p> <p>GDB prefers an elf file, but I think you can use the Restore command to load a raw binary into flash as long as you specify the start address</p><div style="clear:both;"></div>