OTA DFU NRF51822 Bootloader

[Enes]

I created a DFU package from the HEX file through following command nrfutil pkg generate —hw-version 51 —sd-req 0x5A —application-version 4 —application /Users/username/Desktop/d/nrf51822_beacon_app.hex —key-file /Users/username/Desktop/d/key.pem /Users/username/Desktop/d/dle_app_dfu_packagbbe.zip

I open the nRF Toolbox app on my android device, I press SW1 button on the beacon and on the DFU section of the mobile app, I selected DfuTarg (the Beacon). I downloaded on my Android device and selected the .zip file I created. After I click the Upload, after a while I am getting DFU REMOTE OPERATION FAILED message and also while trying to do DFU, blue LED directly turn into Purple on the device.

My first question is what I need to do be able upload my application to the Beacon?

My second question is I am using out of the box Beacon firmware, do I need to do some process with bootloader to be able to send my application through OTA DFU? If yes, how?

Thank you very much.

[Hung Bui]

Hi Enes, 

The beacon DFU is supposed to update Nordic's Beacon image only. When you creating your image, you already generate and used your own key file which wouldn't recognized by the bootloader. The operation will be failed. 

The beacon was not made to be a development board but more like a reference design. 

If you want to run your own firmware on the beacon, you would need to use a programmer and erase the chip's bootloader and flash your own firmware via the SWD interface.

[Enes]

Thanks for your reply Hung,

So you are referring that there is no way to update my own firmware through OTA DFU to beacon without erasing the chip's bootlader which sounds like ONLY possible with SWD interface which requires a cable right? Could you please provide me the information about which kind of cable I need to send the code I have to the beacon through SWD? Thank you very much.

[Hung Bui]

Correct. You can have a look at this thread. 

If you don't plan to buy the needle cable, you may need to do some soldering at least 4 pins needed: GND, VCC, SWDIO; SWDCLK.