nrf52840 PDK is not recognized by computer anymore

[cdugue]

I used to program my PCBs using the nrf52840 PDK, however, my mac no longer recognized the PDK. The PDK turns on and the application runs as LED 4 blinks but the LEDs next to the PCA10056 do not turn on so I believe there is an issue with the debugging chip.

Any ideas on what is happening?

Thanks

[Sigurd]

Hi,

Please go through the list in this post.

[cdugue]

Hi,

I went through this list already without any success. Sorry, I should have mentioned it.

[Sigurd]

Also make sure that the nRF power source switch is set to VDD and SW6 switch is in DEFAULT position.

[cdugue]

I can confirm that both switches are in the correct position.

[Sigurd]

Are you able to communicate with the debugger ?

If you use the command: nrfjprog -i   , do you see the Segger J-Link serialnumber? Do you get any error codes?

On step 4 in the list, it does not show up as "BOOTLOADER" ? 

[cdugue]

No, I cannot communicate with the debugger I get "Connecting to J-Link via USB...FAILED".

Using the command nrfjprog -i  does not return anything, no serial number, no error codes.

Performing step 4, does not make my board show up as Bootloader.

The J-Link interface does not show up in my USB devices in Mac whereas when I connect the same USB cable to another board it does show up. I think the USB port might be damaged, although I get the correct power. Otherwise, the PCA10056 might be damaged?

[Sigurd]

Could you measure the voltage over TP4 and TP3 ?