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:

[Amanda Hsieh]

Hi James, 

JamesD said:

I can put batteries to the unit if that would be better?

 No, just give power by J2. 

Here is the https://www.nordicsemi.com/Software-and-tools/Development-Tools/nRF-Command-Line-Tools. 

How do you connect your hardware device with nRF52DK? Could you provide the picture? Do you use DK's Debug output to connect with your custom device? Please also provide the power to the custom device separately. 

What voltage of VTref does the J-Link Commander get? Please check by the J-Link Commander and make sure it detects VTref as 3.3v. 

-Amanda H.

[JamesD]

VTref is at 3.3v according to J-Link commander.

Checking out the post you've sent now

[Amanda Hsieh]

Do you refer to this thread to modify the connection?

-Amanda H.