NRF52 not response when connecting to pc via USB

[SuperPoorUser]

Hi:

I got an NRF52 EVK,  it works normally.

But now the EVK doesn't  response when connecting to pc via USB.

The LED "LED RG" doesn't light up.

Any idea to check it?

Thanks

[SuperPoorUser]

Hi:

        After check , we have 2 pcs of nrf52-dk in this situation.

1.  the board is nRF52-DK
2. the 'LED RG' is the name found in the schematic.
3. Sorry for my short description

           The situation in detail

            => Originally, when I connect the nRF52-DK to a Windows PC

                 The LED 'LD5' (LED RG?) on NRF52-DK flashes,

                 PC recognizes the nRF52-DK board and open the a folder to show the J-LINK or something ...

                  I can find the NRF52-DK and link when I open nrf-go

            => Now, When I attach my NRF52-DK to the Windows PC,

                  the LED 'LD5' doesn't flash.

                  PC doesn't recognize the board => no open-folder, cannot find any com port of NRF52-DK.

                 

              

[awneil]

SuperPoorUser said:

The LED 'LD5' (LED RG?) on NRF52-DK flashes

So that's the status light for the onboard J-Link:

https://infocenter.nordicsemi.com/topic/ug_nrf52832_dk/UG/nrf52_DK/interf_mcu.html

SuperPoorUser said:

Now, When I attach my NRF52-DK to the Windows PC,

                  the LED 'LD5' doesn't flash.

                  PC doesn't recognize the board => no open-folder, cannot find any com port of NRF52-DK

Dodgy USB cable?

Broken USB socket on the DK?

Have you changed settings so  that the onboard J-Link is no longer powered from the USB:

https://infocenter.nordicsemi.com/topic/ug_nrf52832_dk/UG/nrf52_DK/hw_power_sup.html

[SuperPoorUser]

I did not change any H/W settings on nRF52-DK, 

what I did to the PCB is 

    USB cable connection

    Power Switch to on/off 

    Button1 ~ Button4

=> and more 

     The 2 PCBs are not work  but on both PCBS, the LED1 ~ LED3 are on  LED4 is off,

     I'm not sure that is a clue or not.