https://devzone.nordicsemi.com/f/nordic-q-a/22084/debugging-application-starts-bootloaderHello, i a have a problem debugging application with bootloader installed. I work with GCC for the application. What is happening is the following: If i program application with DFU, and then lauch Eclipse debug it works. But if i do some changesen-USTelligent Community 13Tue, 16 May 2017 11:24:14 GMThttps://devzone.nordicsemi.com/thread/86766?ContentTypeID=1Tue, 16 May 2017 11:24:14 GMT137ad170-7792-4731-bb38-c0d22fbe4515:57c2e749-5b9d-4ba4-a4a4-ed50943ee15bbjorn-spockeli<p>@turboj: You need to generate a bootloader settings hex using nrfutil every time you recompile the application and merge it with the bootloader hex. This is explained in Appendix 1 of <a href="https://devzone.nordicsemi.com/blogs/1085/getting-started-with-nordics-secure-dfu-bootloader/">this</a> blog. It should be easy to add this as a post build step in Eclipse.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/86765?ContentTypeID=1Tue, 16 May 2017 09:55:12 GMT137ad170-7792-4731-bb38-c0d22fbe4515:52edb9c7-07a7-4990-8459-a56e04de9933Turbo J<p>The bootloader keeps a checksum (CRC) of the application when it is flashed via DFU. When you change the application later via SWD, the bootloader - which runs on reset before the app - checks this CRC and refuses to start a modified program.</p> <p>Workaround: Flash the bootloader anew, too. The default bootloader settings page contains a blank CRC value that would fit any application program flashed via SWD.</p><div style="clear:both;"></div>