Unbricking a nrf9160-DK

[Seth_Kazarians]

I seemed to have bricked (or pseudo-bricked) my 9160-DK.  

In the process of trying to set an APN for my carrier, I seemed to have gotten the modem into a state where it is refusing to respond to most commands.  

The Kconfig settings I was trying before this happened were:

CONFIG_PDN=y

CONFIG_PDN_DEFAULTS_OVERRIDE=y

CONFIG_PDN_DEFAULT_APN="hologram"

 

After that, the modem has refused to respond to any AT commands.  (See LTE Monitor Screenshot.)  This is true even after commenting out those lines and flashing. 

Also, trying to program firmware is no longer working.  I've tried both programming the main firmware as well as the modem firmware.  

What are the next steps I can try to fix this?

[Naeem Maroof]

Hi Seth,

Thank you for contacting DevZone at NordicSemi.

I am not sure what has happened, or how to fully resolve it.

Were there any changes / updates to the JLink?

We can see that the programmer detects the DK, but the error is coming from the JLink DLL

This case was also having similar error, and changing jlink-connector resolved their problem. 

You can also try updating to latest tools (like programmer v3.0.9)

BR,

Naeem

[Seth_Kazarians]

I have been updating my apps (nRF Connect, LTE Link Monitor, Programmer, etc.).   I did update to the v3.0.9 Programmer, and that didn't solve the issue.  

I tried programming a different example (at_client), and that seems to have gotten the modem responding to AT commands again.  I'm not sure what's going on that's causing this issue, because the Kconfig settings were all reverted and built cleanly on the https_client example.  

[Naeem Maroof]

Seth_Kazarians said:

because the Kconfig settings were all reverted and built cleanly on the https_client example

could be the case.

Good to know that your issue is resolved either way.

[Seth_Kazarians]

Agreed.  

Is there a way to know which Kconfig settings will not be reverted when removed?

[Naeem Maroof]

Hi Seth,

I am note sure about it, as I haven't bricked my DK. But, if the DK (hardware) is working correctly, and you change / update configurations, you could always check in ./build/zephyr/.config that which configurations are going to take place with this built.