We are working with the ConnectCore 6UL SBC Pro and are looking to add support for UART2, 2-wire RS-232. The ConnectCore 6UL SBC Pro Hardware Reference Manual (linked below) says "I/O expander UART2, 2-wire RS-232 port is not supported by default. If your application requires this port, please contact Digi technical support at www.digi.com/support".
This question is in response to this note. I assume there is something that needs to be set up to make this work.