Every device/sensor communicates through a centralized bus which is essentially a messaging system (e.g. MIL STD 1553, ARINC 429). Furthermore, every device has

Every device/sensor communicates through a centralized bus which is essentially a messaging system (e.g. MIL STD 1553, ARINC 429). Furthermore, every device has a set of expected outputs for every internal or external input. You can build a software model that mimics that. Then it's just a matter of connecting your software to the bus. Flight control software aggregates sensory inputs from the bus, reconciles redundancies, and makes flight decisions.