nrfutil flash with full erase breaks flashing

RE: nrfutil flash with full erase breaks flashing

Konstantin Klitenik — Fri, 03 Oct 2025 13:39:26 GMT

This behavior is not consistent. Sometimes I can use just "west flash", other times i need to use "west flash --recover". I haven't found a pattern on when this protection happens. We are now using nrf54.

RE: nrfutil flash with full erase breaks flashing

Amanda Hsieh — Fri, 03 Oct 2025 13:36:55 GMT

As I mentioned, the issue is that the Application core access port is enabled, and it needs to be unlocked with "west flash --recover". This is not caused by nrfutil. Actually, the nrfutil wraps the nrfjprog. nRF9151 is new, but it should be quite similar to nRF9160 and the nRF52 series. The APPROTECT is enabled by default. You can refer to Checking if APPROTECT is enabled for the APPROTECT enable/disable. (75) Working with the nRF52 Series' improved APPROTECT - Blogs - Nordic Blog - Nordic DevZone shows that the command tool and codes can be used.

RE: nrfutil flash with full erase breaks flashing

Konstantin Klitenik — Thu, 02 Oct 2025 19:23:34 GMT

Still same issue, after upgrade. Here's nrfutil list:

Command Version Description
completion 1.5.0
device 2.14.2 Device discovery, programming, and operations such as erase, reset, and recovery.

Found 2 installed command(s)

RE: nrfutil flash with full erase breaks flashing

Amanda Hsieh — Thu, 24 Jul 2025 12:48:40 GMT

Try to run "nrfutil self-upgrade" and "nrfutil upgrade" to update the tool. If that still cannot help, please provide the return by "nrfutil list".

RE: nrfutil flash with full erase breaks flashing

Konstantin Klitenik — Thu, 24 Jul 2025 12:24:14 GMT

No. An update from @nordic would be nice...

RE: nrfutil flash with full erase breaks flashing

Reimer — Thu, 24 Jul 2025 09:03:39 GMT

Hey Konstantin

I'm curious to know if you found a solution since I'm experiencing the same problem and can't seem to find a way to solve it.

Kind regards,

Reimer

RE: nrfutil flash with full erase breaks flashing

Konstantin Klitenik — Wed, 30 Apr 2025 23:40:10 GMT

Clearly. But what causes it to get in that state with nrfutil but not with nrfjprog.

RE: nrfutil flash with full erase breaks flashing

Amanda Hsieh — Wed, 30 Apr 2025 18:52:42 GMT

Hi,

[quote user=""]* 1051272415: Failed to attach to target: The Application core access port is protected (All) (NotAvailableBecauseProtection)[/quote]

It seems the device is using a readback protection, so it needs "--recover" to unlock.

See Optional programming parameters.

Regards,
Amanda H.