The present disclosure relates to system(s) and method(s) for interactively controlling the course of a functional simulation of DUV/SUV. The system comprises a testbench and the DUV/SUV connected to the testbench. The testbench generates a set of input data/packets as a stimulus to be processed by the DUV/SUV. The set of input data/packets is generated to simulate and verify the DUV/SUV. Further, the testbench identifies a pre-defined event at runtime during the simulation. Upon identification of the event, the testbench is configured to pause the simulation and transmit a notification message to a user indicating the occurrence of the event. Further, the testbench waits for a pre-defined time interval to receive one or more user inputs. The testbench further generates new stimulus based on the one or more user inputs and resumes the paused simulation with the new stimulus, thereby controlling the course of the functional simulation.