A design and implementation of watchdog based on observer pattern and finite state machine

In this paper, a method with Observer Pattern and Finite State Machine for watchdog implementation is proposed. By using Observer Pattern and Finite State Machine, the watchdog will be notified automatically when the program´s state changes. Complex protection strategies can be applied based on the transition of different states. The simulation indicates great improvement on reliability and maintainability of the program, especially for those complex programs with multi-task or multi-interrupt.