Unable to Access SWD on nRF52840

RE: Unable to Access SWD on nRF52840

Vidar Berg — Mon, 26 Sep 2022 08:29:00 GMT

Hi,

I see. But then I don't really understand why the debug interface becomes inaccessible. I would still suggest you try "nrfjprog --recover" to see if it might help.

The one thing that may "brick" the device is if you enable the DCDC regulator on a module which doesn't include the optional DCDC inductors. But the DCDC reg. is disabled by default in our nRF5 SDK examples, so it should not be on unless you have explicitly enabled it.

RE: Unable to Access SWD on nRF52840

WestCoastDaz — Sun, 25 Sep 2022 18:22:08 GMT

Vidar Berg

Hi,

I don't believe I have a module with the new chip revision as I purchased these modules in 2021 and I haven't had to perform `--recover` operation with any of these modules. That said I will try running this operation with the newer tools installed. If that doesn't work is there anything else I can try?

Thanks,

RE: Unable to Access SWD on nRF52840

Vidar Berg — Fri, 23 Sep 2022 06:35:17 GMT

Hello,

The module probably has the new chip revision where we have changed the approtect mechanism. Please see my answer here: nRF52833 (Custom Board) halts when JLink is connected . Or have you tried to run "nrfjprog --recover" already?

Best regards,

Vidar