nRF52840 - DFU Mode won't start

[Roxas]

Today I received my first CMSIS-DAP debug probe (Pitaya link) and tried to integrate it into my development environment.
Unfortunately, I must have broken my Pitaya Go (Nordic Semiconductor nRF52840 SoC) in this process.

After some time I noticed that I could no longer switch on the DFU mode on the Pitaya Go.
I hold down the USER button and then press the reset button.
As soon as I supply the Pitaya Go with Storm via USB, the power LED lights up but not the indicator RGB LED. I am also not sure if the example code is executed at all.

I have already tried to upload the pitaya_cli example project using the pitaya link and "pyocd flash -t nrf52840 nrf52840_xxaa.hex" without success.
What I found strange is that it didn't give me an error message back and it looked like it was successful.

Is there another way to get it working again?

Thanks for helping

[Kenneth]

Sorry, but I think this question is best directed to pitaya go support, we don't have any experience with this development plarform.

Kenneth

[Roxas]

Solution: https://community.makerdiary.com/t/pitaya-go-dfu-mode/407

By: cmd

Real quick sanity check: I’m not sure that the CLI example uses the LED at all (at least not while it’s idle, perhaps it blinks on UART tx/rx?

That said, I had something similar happen to me a few times, and it almost always ended up being that I did something to the bootloader or the UICR registers when I was using other bootloaders.

I always like to start fresh with a chip I know is blank: pyocd erase -t nrf52840 --chip.
Then, re-flash the bootloader.
After that, re-flash blinky.
At that point, give the chip a kick: pyocd reset -t nrf52840 and it should start blinking.