DFU example doesn't work. need explain step by step

[Mikhail]

Hi!

nRF52. S132, SDK13.

I try to use ble_dfu_send_hex example.

1. what shoul I do first? via nrf gostudio load SD. correct?

Which SD? from this folder (dfu_test_softdevice_s132) Or usual SD (s132_nrf52_4.0.2_softdevice)

2. what should I do next?

[Hung Bui]

Hi Mikhail,

The buttonless project is simply a showcase how you enter the bootloader by a command via BLE instead of press a button and trigger a reset. Basically what it does is to wait for the command on a characteristic (DFU service) and when there is a write command it will write to bootloader setting in flash a flag and then trigger a reset. After that the bootloader when booting up will check the flag and enter DFU mode.

You need to include ble_dfu.c into your project and implement that dfu service in your application. You need to init it and also add the ble_dfu_on_ble_evt() into ble_evt_dispatch() as normal service.

There is nothing about keys here so you don't need public_key.c

Note that you need both the bootloader and the buttonless dfu, they are not the same.

[Mikhail]

Ok. I need first type of bootloader with keys. But I want to do one thing- I want to flash my app via programmer (J-link) after I want to have a possibility upgrade via DFU. Which settings should set in my app?

[Mikhail]

Hung, final question- how to make DFU with button and with first flashed .hex. I mean, I flash .hex as usual. After that If I press button and reboot, I will can flash via DFUTarg. How to do it?

[Hung Bui]

Hi Mikhail,

Sorry I didn't see your last comment. Yes you can flash your app using Jlink and then use DFU OTA later. You have 2 option to enter DFU , via holding a button when the board reset or enter it via BLE command (buttonless example). Please have a look at appendix 2 in my blog.

After you enter DFU bootloader with a button, you should do DFU OTA, not flashing via Jlink.

[Mikhail]

Now I try do next steps: - flash SD, flash Bootloader, flash .hex app- all via J-link. Correct? After that I don't have work my app, but I see DFUTarg in the Air. Is it normal? I nothink changed in .hex app. What I did wrong? Thanks for help.