https://devzone.nordicsemi.com/f/nordic-q-a/6219/sd-8-0-sdk-8-0-ota-dfuI&#39;ve been looking into the OTA DFU dfu_init_template.c. It seems that dfu_init_postvalidate function can be used to perform a CRC check. However, in bootloader.c it seems the bootloader_app_is_valid function also performs a CRC check. Which one woulden-USTelligent Community 13Thu, 03 Dec 2015 07:15:56 GMThttps://devzone.nordicsemi.com/thread/21769?ContentTypeID=1Thu, 03 Dec 2015 07:15:56 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b32b077c-d06f-47d6-886f-ffde18c5b4bbshubham<p>The one given in dfu_init_template.c is the redundant one, don&#39;t call that function. And i think <strong>dfu_image_validate</strong> is the function which is defined in <strong>dfu_dual_bank.c</strong>, which is internally called from dfu_transport_ble.c. and the one <strong>bootloader_app_is_valid</strong> defined in <strong>bootloader.c</strong> is used to verify that the application image which is present now in internal flash is valid, at the time of boot of nrf, if valid it switches to application.</p><div style="clear:both;"></div>