Describing embedded system’s processing behavior can be extremely difficult. Common computation models are sequential program model, communicating process model, state machine model, dataflow model, object-oriented model. We might consider a Finite-state machine (FSM) model, describing the system as:
- Possible states
E.g., Idle, GoingUp, GoingDn, DoorOpen
- Possible transitions from one state to another based on input
E.g., req > floor
- Actions that occur in each state
E.g., In the GoingUp state, u,d,o,t = 1,0,0,0 (up = 1, down, open, and timer_start = 0).