

Hi,
See how-to-use-rtt. documentation to get the logging output using Real Time Transfer (RTT), modify the configuration settings of the sample (prj.conf) to override the default UART console:
CONFIG_USE_SEGGER_RTT=y
CONFIG_RTT_CONSOLE=y
CONFIG_UART_CONSOLE=n
Are you using PDK? Which version of NCS are you using?
Are you building hello_world for net core? If so, you should also program the empty firmware for application core.
The nRF5340 PDK has been deprecated with the introduction of the production-level nRF5340 DK. To determine if you have a PDK or DK, check the version number on the sticker on your kit. If the version is 0.11.0 or higher, the kit is an nRF5340 DK.
See the nRF Connect SDK v1.4.0 documentation for the last release supporting the nRF5340 PDK.
-Amanda H.