Error programming external nRF52 with Dev Kit: Could not fetch memory size of target devkit: Error: Error occured when get library info. Errorcode: CouldNotOpenDevice (0x4) Lowlevel error: Unknown value (ffffff24)

[bali]

I'm trying to program an nRF52810 on a custom PCB using the nRF52-DK and am getting this error ((0x4) Lowlevel error: Unknown value (ffffff24)) when connecting with nRF Connect 

DK Debug Out	Custom PCB
VTG	3.3V
VDD	3.3V
GND_DETECT GND	GND
SWDIO	SWDIO
SWDCLK	SWDCLK

I've confirmed power on the PCB is 3.3V and checked the programming header connections also, i tried to power my PCB from:

      - An external power supply 3.3V. 

      - and from the DK.

to ensure logic level compatibility.

But in both cases i'm getting the same error so i'don't think it's a logic level compatibility.

I've also tried to update firmware of the DK with the latest found on nordic website.

so I'm not sure what could be the issue. Thanks in advance for any help.

[bali]

when i tried the nrfjprog --recover --log command that's what i got 8765.log.log