How to erase a protected firmware program (knowing the protected password)

[JamesD]

I'm trying to deploy a new firmware to my hardware device but I get the following error in the nrf  Connect 3.6.1 programmer (v1.4.8):

• 16:47:36.937

  Error when getting device info: Error: Error: Error occured when get device info. Errorcode: CouldNotCallFunction (0x9) Lowlevel error: NOT_AVAILABLE_BECAUSE_PROTECTION (ffffffa6)
• 16:47:36.937
  Could not fetch memory size of target devkit: Cannot read property 'family' of undefined

I cannot read nor erase from the device through the programmer because of this error.

I assume this is because the device is password protected. I know this password, is there a way to erase the device's current firmware?

(I'm using the NRF52-DK to connect/program with it, and the pins are accessible, which is how I'm connecting)

[JamesD]

Hi,

2.93V is the output on the VDD to my device of the SDK. (I can put batteries to the unit if that would be better?)
The password I use only to get inside the firmware of the device when I connect with Bluetooth, ensuring no external people can read it out.
It has no further purpose

I don't have a command line tool, which would you recommend?

here's a pick of the sdk voltage readout:

[JamesD]

Hi again Amanda,

thanks for taking the time to respond so far,

Wiring now is as followed:

So I'm currently not using the debug output to connect with the device

I've provided power to the custom device by batteries now, no change in the result.

I'm connecting the device via USB, so I'm not familiar with how to check the voltage to the SDK?

log via commandline command:
 nrfjprog.exe -f NRF52 --recover --log:
0250.log.log

[Amanda Hsieh]

Hi, 

Have a look at the connection in this thread.

JamesD said:

I'm connecting the device via USB, so I'm not familiar with how to check the voltage to the SDK?

 Open J-Link Commander, and check the VTref as the figure I replied in the previous. 

-Amanda H.