https://devzone.nordicsemi.com/f/nordic-q-a/15570/proprietary-otaI am working on a bootloader for a client. I’ve been looking at the DFU example that Nordic has. The BLE version of the DFU needs to have the special format using the “nrfutil dfu genpkg” command. The customer has their own proprietary OTA system to transferen-USTelligent Community 13Mon, 08 Aug 2016 09:29:08 GMThttps://devzone.nordicsemi.com/thread/59429?ContentTypeID=1Mon, 08 Aug 2016 09:29:08 GMT137ad170-7792-4731-bb38-c0d22fbe4515:1eb6720b-3dbc-491d-99d8-ce39da461c18bjorn-spockeli<p>Yes, this is possible. The size of the softdevice is hardcoded in an info structure at 0x3000, see <code>SD_SIZE_GET()</code> macro in <code>nrf_sdm.h</code>.</p> <p>You do not need generate the application firmware packet using nrfutil, as the information in the firmware packet is only used to initiate the DFU process. The hexfile it self is not altered.</p> <p>You will have decide if you want to use the SoftDevice Flash API or use the NVMC(Non-volatile Memory controller) directly when writing to flash.</p> <p>If you want to do the latter, then I recommend that you take a look at <a href="https://devzone.nordicsemi.com/question/54763/sd_flash_write-implementation-without-softdevice/">this</a> post, where you&#39;ll find a softdevice independent flash library(nrf_flash) written by a colleague of mine.</p> <p>Bjørn</p><div style="clear:both;"></div>