I think I broke my bootloader, looking for help.

[ulao]

So I got me one of these

and after a day of making it work on windows I was able to lunch visual code from wsl and compile. the next day I found how to make a flash with nrfutil and was able to create a zip. So I pressed the button and the LED changed its blink rate, and I ran a few commands.

nrfutil keys generate private.key       

nrfutil pkg generate --hw-version 52 --sd-req 0x00 --application nrf52832_xxaa.hex --application-version 1 --key-file private.key app_dfu_package.zip    

nrfutil dfu serial -p COM5 -pkg app_dfu_package.zip -b 115200

I then got this

  [####################################]  100%
Device programmed.

now the device is dead. I tried holding down the button on insert and pressing after it was in. no USB chine no led. I flashed the gpiote example in hopes it woudl be a BT device that used GPIO pins, but it just make a brick.

Can this be fixed? If not, what did I do wrong?

[James168]

nRF52840 dongle bootloader,

0511.pca10059_bootloader.zip

[ulao]

Not sure I understand this reply. My device is dead so a hex file will not help me any unless there is a ISP or other means to flash it. Can I connect this dongle to my dev board?

[khelmutlord]

You can solder a 10 pin header to the bottom of the dongle, then connect to an external debugger.

For most development work I'd recommend a full development kit, it's not a great experience to use the dongle and use serial DFU vs. a full debugger.

My guess is that the bootloader fails to use an image with your own keys and dies before executing the application.

[ulao]

I have a full dev kit, I just need to know how to make the dongle work as my device will also use that.

DFU is not new, this is a hugely common way to update firmware, why does everyone keep dodging the question, on here, in email, online... DFU is for the user experience why is this so difficult?

Yes, I have a dev board, that is not my issue.I need to know how to flash the DFU  correctly and how to recover it ( this should not even be happening). 

I have the 10 pin on the bottom, but I'd need some type of wiring guide to show what I need to older it to. Guessing it connects to my dev board somehow.