What ways can you communicate with external hardware?

Getting UE to receive commands from external controllers is easy. But what if we want Unreal Engine to send data to a controller? We have a few beta custom made controllers that have simple head-up indicators. We need to get UE to trigger the Lights on the controllers on certain events.

For instance, If the player object enters a trigger volume, the heads up light on the controller needs to come on.

What ways can Unreal Engine communicate with external hardware? We can try to adapt the controller to those ways.

Unreal C++ plugins provide a large amount of feedom to recive data from external sources as well as transmiting data throught network or other libs etc

start by understanding the basic coding up of a camera and this might lead to better understaning of what you will need.