unable to detect the nrf board in ubuntu

[Achyuth]

Hy , 

After i a buildng and flashing the hci_rpmsg as a cupapp . i flash the board 

Then when i am checking the board with ubuntu laptop .i am not able to see the board address .

is there any steps required for this setup?

[Achyuth]

And i tried it with theNRF  power sorce as VDD