https://devzone.nordicsemi.com/f/nordic-q-a/47923/bootloader-and-external-applicationIn 15.3, there is a new application type valid for DFU, external app. When loaded through DFU, the program just sits there in bank1, and doesn&#39;t get sent anywhere. I&#39;d like to use this as I assume it is intended, and send the program over to another MCUen-USTelligent Community 13Thu, 30 May 2019 17:00:38 GMThttps://devzone.nordicsemi.com/thread/190096?ContentTypeID=1Thu, 30 May 2019 17:00:38 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c1f94259-dc98-44a5-a192-d14b5a7a393aMike<p>Nevermind, this was a me bug.&nbsp; It works fine.</p> <p>I had a&nbsp;nrf_dfu_settings_init(true) instead of (false), and it was initialzing the sd backend instead of nvmc.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/190070?ContentTypeID=1Thu, 30 May 2019 13:36:46 GMT137ad170-7792-4731-bb38-c0d22fbe4515:1da2e376-5780-4eb6-8dbe-0d00273d1e02Mike<p>Also, I lifted this code mostly from nrf_bootloader_fw_activate().&nbsp; It looks to me like I&#39;m doing it the same way this function uses the flash calls... the only weird thing I see in the docs is the following line:</p> <p>This function relies on accessing MBR commands through supervisor calls. It does not rely on the SoftDevice for flash operations.</p> <p>Not sure what this means.&nbsp; In reading through the code, the stuff in app_activate(), image_copy(), etc seems to use the same stuff I use.&nbsp; The only difference I see is that image_copy turns on the WDT.&nbsp; That shouldn&#39;t be necessary to write to flash though, right?</p><div style="clear:both;"></div>