Dfu secure serial bootloader not working.

[kunal]

The following steps i used to Flash my nrf52 DK with DFu Serial secure.

1. Downloaded and installed a)nrf5_SDK_13.0.0 b)nrfgo Studio c) keilv5 d)Python 2.7.9 e) pip f) nrfutil

2. next I compiled the experimental_DFU_secure_serial from examples in 13.0.0SDK and got Errors in Micro_ecc.h compilation. I later was able to compile the library and generate private.key and public key.

3. i generated the private.key and then corresponding public_key, saved private key on my PC and replaced the dfu_ public_key.c (that came in d example as Default) with my new public_key.

4. now i compiled without any Errors and was able to get the nrf52832_xxaa.hex file for the Bootloader Code

5. I then generated bootloader Settings nrfutil settings generate --family NRF52 --application C:\Users\ParthibanK\Downloads\nRF5_SDK_13.0.0_04a0bfd\examples\peripheral\blinky\pca10040\s132\arm5_no_packs_build\nrf52832_xxaa.hex --application-version 0 --bootloader-version 0 --bl-settings-version 1 C:\Users\ParthibanK\Documents\Bootloader_settings2.hex

6)I then merged bootloader Settings and nrf52832_xxaa.hex

C:\Windows\system32>mergehex --merge C:\Users\ParthibanK\Documents\Bootloader_settings2.hex C:\Users\ParthibanK\Downloads\nRF5_SDK_13.0.0_04a0bfd\examples\dfu\experimental_bootloader_secure_serial\pca10040\s132\arm5_no_packs_build\nrf52832_xxaa_s132.hex --output C:\Users\ParthibanK\Documents\BootSettv1.hex Parsing input hex files. Merging files. Storing merged file.

7. Now i opened Nrfgo Studio and first Flashed the softdevice [SDK132] hex file from componnets\softdevice and then i flashed Bootloader as BootSettv1.hex

8. as i understood from your instructions after a reset the board should be able to connect with my Android phone as "DfuTarg". This does not happen. I cannot fine any Bluetooth Connection with thew Name DfuTarg and so i assumed no Connection is being established also do not know wher the mistake lies as i i have followed all the necessary instructions .

Please help

[bjorn-spockeli]

Hi Kunal,

up to point 4 you're on the right track, but on point 5 you should set the application version and bootloader version to 1.

Note that when you generate the settings page and merge it with the bootloader you will set the "Bank0 Bank Code" to 0x00000001 (NRF_DFU_BANK_VALID_APP), i.e. indicating that there is a valid application in bank 0. The bootloader will check the Bank0 Bank Code field on the bootloader settings page will branch to the application if it is set to 0x00000001 (NRF_DFU_BANK_VALID_APP). If there is no application has been flashed to the device then it will branch to an empty flash region, reset and repeat.

You should be able to put the device in bootloader mode by holding down the Bootloader button(Button 4) on your nRF52 DK, while you power-cycle your board. This will force the device to stay in bootloader mode and not branch to the application, even though the NRF_DFU_BANK_VALID_APP is set. The board should then start to advertise as "DfuTarg".

Best regards

Bjørn

[kunal]

I changed application Version to 1 and Bootloader Version to 1 but this hasnt effected the board. actually my application blinky is working as i can see the LED's always blinking but when i press the Button 4 the LED's are still blinking which shows that the board is not entering Bootloader mode and still in application. neither am i able to see the 'DFU Targ'

I am attaching my bootsettings & nrfprog screenshots. Pls help

NRFGOsetupnrfgoSetup.PNG

bootsettings BOOTsettings.PNG

[bjorn-spockeli]

Are you holding down button 4 while you turn on and off the nRF52 DK?

[kunal]

i Held button 4 and did power cycle , it entered bootloader mode now but detecting DFUTarg is not Happening. The sam process works very well with the secure_bootloader_ble example but experimental_bootloader_secure_serial example never shows DFU Targ on entering Bootloader mode.

[bjorn-spockeli]

@kunal: The experimental_bootloader_secure_serial is a serial bootloader, i.e. you updated the firmware via the UART interface and not using BLE. In fact the serial bootloader does not enable the SoftDevice at all.