I followed this guide which suggested to connect the red and brown wires on the RS485 adapter.
The RS485 adapter is not showing up in Settings > IO.
I ssh’d in and I can see it w/ lsusb
root@nanopi:~# lsusb
Bus 003 Device 002: ID 0403:6001 Future Technology Devices International, Ltd FT232 Serial (UART) IC
Should the RS485 <> USB adapter be visible in Settings > IO?