RE: Shell - getting started

Einar Thorsrud — Fri, 25 Feb 2022 12:45:12 GMT

Hi,

UART0 is used by default. You can use an overlay to specify another UART instance with chosen if you want to use another instance (see an example of that in usb.overlay the Shell sample, though here USB is specified instead of a different UART instance). You can refer to overlay-usb.conf from the same sample to see how you can specify another transport.

Regarding default configurations that comes from the Kconfig files that define the configurations, for instance backends comes from zephyr\subsys\shell\backends\Kconfig.backends. There you can see for instance SHELL_BACKEND_SERIAL use the device tree (if present). And for the nRF9160 DK this ends up in zephyr\boards\arm\nrf9160dk_nrf9160\nrf9160dk_nrf9160_common.dts where that is specified to uart0. To change that use an overlay as explained above.