How do I use the screen data transfer port on the NT31/631 Programmable Terminals?
Use serial port A with the protocol set to "not used."
("Not used" means that the port will not be used for communications with the host. Serial port B cannot be used to transfer screen data.)
With NT31/NT631, it is recommended to use serial port A to transfer screen data, and use serial port B to communicate with the host.
For details, refer to NT31/NT31C Setup Manual or NT631/NT631C Setup Manual.