Failed to Connect Target

[Sahil Anchal]

I procurred two NRF52DK boards and in both the boards I am facing the similar issue of "Failed to Connect the Target".  When I am running the nrfutil device recover command, it showing follwing error:
x Failed to recover 1050389761, Emulator error: Failed to open connection
Error: One or more recover tasks failed:
* 1050389761: Emulator error: Failed to open connection (Generic)

also when running nrfjprog --recover -f nrf52 command
it is shwoing the following error:
"Recovering device. This operation might take 30s.
[error] [ Worker] - Encountered error while performing post-recover cleanup. -90: Access protection is enabled, can't read device version.
[error] [ Client] - Encountered error -21: Command recover executed for 30178 milliseconds with result -21
ERROR: Recover failed. Please make sure that the correct device family is given
ERROR: and try again."


I am not able to use these boards at all and sort of struck at this and have been wasting my time for the last one week trying every bit of commands provided to recover the device but have no success at all so far.

[dejans]

Hi,

Which versions of the tools (nrfjprog, nrfutil, nrfutil device) do you use?

Best regards,
Dejan

[Sahil Anchal]

Hi,
I am using the folliwng versions:
nrfutil --version: nrfutil 8.0.0 (54d8087 2025-01-07)
nrfutil device --version: nrfutil-device 2.11.0 (5778cc4 2025-05-15)

nrfjprog --version: 10.24.2 external
JLinkARM.dll version 7.66b

Regards

[anaetechengineer]

I just had the same issue with a brand ne dev board 3.0.2, 2024.34.  I erased the device using Segger's J-Flash V8.38.  The device then programmed using nrfutil.

[dejans]

Hi Sahil Anchal,

This issue seems to be caused by active watchdog timer timeout. Please refer to this flash erase failure errata.

Best regards,
Dejan

[Sahil Anchal]

Hi,

Thanks, but what is the workaround for this? It's saying 'Try Again.' What does it mean?

Regards

[Sahil Anchal]

Hi,

Thanks, but I'm unable to connect with the device, which is the problem.

[anaetechengineer]

I can't add to my post above.  Very rarely is the hardware at fault and its very rare that I am the only person facing an issue - usually that points to a mistake on my part.  Yours was the only post that showed up on Google for this problem which would normally mean that we've missed something obvious. I needed to get a BLE sniffer working yesterday and so out of desparation I used the Segger JFlash tool to fully erase my dev. board. That using the JFlash tool fixed the problem suggests that we are not doing anything wrong.  It is possible, that as Nordic are suggesting, there was a random/watchdog timing issue but in my case JFlash just connected and worked first time. 

My board is an nRF52840-DK, PCA10056/ 3.0.2/ 2024.34/ 1050212472

Good luck.

[dejans]

Hi,

anaetechengineer Errata is given for nrf52832.

Sahil Anchal We will investigate this issue internally. I will get back to you with status update by the end of next week.

Best regards,
Dejan