https://devzone.nordicsemi.com/f/nordic-q-a/9499/nrf-toolbox-application-sends-wrong-softdevice-image-size-in-start-packetWhile ota dfu via nrf toolbox android app, it sends wrong (0x15918) image size in start packet, and also bootloader starts writing softdevice image at address DFU_BANK_0_REGION_START(0x18000) instead of DFU_BANK_1_REGION_START(0x2A000). But it worksen-USTelligent Community 13Thu, 08 Oct 2015 06:04:04 GMThttps://devzone.nordicsemi.com/thread/35058?ContentTypeID=1Thu, 08 Oct 2015 06:04:04 GMT137ad170-7792-4731-bb38-c0d22fbe4515:42c33f28-13cf-44da-886d-9117a91023ceVidar Berg<p>Hi, when preparing a SD image, nrf util will automaticcally remove the UICR section and any byte padding at the end. 0x15918 bytes should be correct if you are using s110 v.8.0.0.</p> <p>A SD image will always be loaded to BANK_0 where the application resides due to its size, see <a href="http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk51.v9.0.0/bledfu_memory_banks.html?cp=4_1_0_4_3_3_1">softdevice update in SDK documentation</a></p> <p>Are you getting any error messages while uploading SD, and have you tried to upload the SD distrubution .zip found in \nRF51_SDK_9.0.0\examples\dfu\ble_dfu_send_hex\test_images_update?</p><div style="clear:both;"></div>