my nrf52833 board cannot start (reset ) normally

[nick yong]

my nrf52833 board cannot work after power. but can start when I run nrfjprog --reset .
but when I power down and power on the nrf52833 board, it do not work.

the following is my board. (No nfc)

please check and tell me .  what caused the reset issue (power off and power on cannot start<boot> the board )
thanks。

[Szabolcs]

Did nrfjprog --reset broke after you removed the resistor, or was it the same before?

Here is a post about using the devkit with an external board: https://devzone.nordicsemi.com/f/nordic-q-a/102480/how-to-program-an-external-board-using-a-dk-board

Please also try to connect to the target with J-Link commander.

[nick yong]

I do have 10K pull up resistor。
the same thing .

I can debug only once. If i need debug again. I must repower and recover reset it again.
my package is QDAA(40pin). different from DIAA(DK)

QFN40 is different from other package?
my code and proj.cnf works well for DK (pin73).

[Szabolcs]

Hi,

the package is only a difference in pin count, the chip inside is the same.

So you can always connect after a recover, and then cannot connect after programming the chip. This tells me that you have a configuration in your project which disabled the debug interface. What project are you flashing on the board? Does this issue occur if you try with another firmware?

[nick yong]

maybe,it is not caused by my code.
sometimes. even the nrfprog recover would fail for error -21

I think the eraseall or recover command would not be affect by my code.