Problems with architecture understanding of an app with secure BLE buttonless DFU

[mjazz]

Hi everybody!

I am new to programming with Nordic SDK and have some questions regarding writing applications with secure and buttonless DFU via BLE.

I have looked through main examples in Nordic infocenter ( BLE Secure DFU Bootloader & Buttonless DFU Template Application). 

Though code is documented well, lack of an overall architecture explanation makes me wonder:

1. Is Buttonless DFU Template Application code enough to run on its own? Of course, after generating keys etc. Unfortunately, I have no ability to check it by myself in the nearest future.

2. If the answer to the previous question is "yes", where should program logic be placed exactly?

3. Should I first set up BLE Secure DFU Bootloader and then run Buttonless DFU Template Application?

That is all for now,

Regards,

I.

[Marjeris Romero]

Hi,

Yes, the Buttonless DFU Template application is enough to run on its own, you can actually test a debug version by programming precompiled hex files as in

examples\dfu\secure_dfu_test_images\ble\nrf52832\sd_s132_bootloader_buttonless_with_setting_page_dfu_secure_ble_debug_with_bonds.hex

for example. See the step by step in how to do it here. Note that the debug version is compiled with a signature public key that only works with the pre-compiled test-images in examples\dfu\secure_dfu_test_images\. You will need to generate your own keys when testing with your own firmware.

You can then modify the template application to include other services or custom services, I will need more information about what you plan to do in order to help you here. If you are new to programming with our SDK I recommend you to start with some of the bluetooth tutorials we have at the Devzone tutorial page.

Best Regards,

Marjeris

[mjazz]

I still can not figure out one thing. 

For example I have some open bootloader currently flashed. As I upload .hex file of Buttonless DFU Template Application - my bootloader will be re-written to a bootloader with secure Device Firmware Update (DFU) functionality? Or I would not be able to flash at all?

Even after reading many posts on devzone and infocenter I can not figure out if we program bootloader and application separately :'(