Simulink® supports debugging with Simulation Stepper, which lets you step back and forth through your simulation. Use the Simulation Stepper to view data and inspect how and when the system changes states. For information, see How Simulation Stepper Helps With Model Analysis.
Simulink also includes the Simulink Debugger, which, like the Simulation Stepper, also enables you to start, stop, and step through a model simulation. For information on the differences between the two tools, see How Stepping Through a Simulation Works.