In the Clocks section of the Preferences window change the B0 clock frequency to 50MHz . Click OK . You are now ready to simulate your design. In the small Simulator window select Step . Waveforms should now appear that correspond to each signal that is being viewed.
Black waveforms are for inputs, blue waveforms are for outputs.
Step the simulation forward a couple of steps and observe the waveforms. Functional Simulation in the Schematic Editor .