Design the combinational circuits for converting binary numbers to decimal and displaying hours, minutes, and seconds.

Design the sequential circuits for controlling the start, stop, and reset functionalities.

Implement simulation models for input devices to simulate user interaction with the stopwatch $($e$.$g$.,$ start button, stop button, reset button$).$

Implement simulation models for output devices to simulate the display of time $($e$.$g$.,$ simulated LEDs or displays$).$

Simulate the functionality of the stopwatch under various scenarios, including starting, stopping, and resetting the time.

Debug any issues encountered during simulation and refine the design as needed.