If your controller has a built-in serial port that is not showing up when you view the Remote System in NI MAX, you likely do not have the NI-Serial drivers installed on the controller.
- Find the controller in the Remote Systems list in NI MAX.
- Click the arrow next to the controller name to expand its sub-list.
- Right-click on Software and select Add/Remove Software.
- In the list of software to install, make sure to include NI-Serial RT.
- Continue through the wizard to finish the installation. Your serial port should now show up under Devices and Interfaces.