Here is the long-awaited by many users article about communicating between two Arduino boards via UART.
Create your own “data package” to exchange information between Arduino boards using a text-based format.
To repeat the example you need to add the uart-led-control library to your XOD workspace.
If you can’t repeat the example described in the article or you are faced with other unexpected errors, be sure to write about it on the forum. The more feedback you give us, the sooner the nodes in this library become part of the XOD libraries.