INVALID_OBJECT Error when try to DFU with nRFConnect

[Dave_couling]

Hi,

I generated by DFU package following the BLOG post: devzone.nordicsemi.com/.../

However I had to make some changes as it seems to be out of date. I used the following script command:

nrfutil dfu genpkg --application-version 1 --application Images\nrf52832_xxaa.hex --sd-req 0x8C --key-file privat.key DFU_Packages\app_dfu_package.zip

I used the private key generated from the Blog's Python example (a whole other can of worms). However when I try to DFU using the nRFConnect BluetoothLE Desktop app I get the following error:

"When writing 'EXECUTE' command to Control Point Characteristic of DFU Target: Operation code 4 (EXECUTE) failed on DFU Target. Result code 5 (INVALID_OBJECT)"

Unfortunately there doesn't seem to be any documentation on the nRFConnect for me to cross reference this error. I noted that the nRFConnect Android app also doesn't work, which leads me to think my DFU package wasn't generated correctly. Any insight into where the issue might be?

Also note I did use my private key to generate a public key which I copied into my Bootloader project named as dfu_public_key.c.

Thanks guys,

p.s. using S132 V3, and SDK 12.3

[John]

I'm not expert enough with nrfutil to know if there is something wrong with the way you are using it. However, here is how I do it in my post build .bat script and it is working: "nrfutil pkg generate --application .\D-21228-release\exe\AppMX_WATER.hex --application-version 0xff --hw-version 52 --sd-req 0x8C --key-file ....\Source\vault\priv.pem D_21228_APP.zip"

Note, that works with both nrfConnect and our mobile application bootloader.