Seleting this menu item will cause the currently visible circuit (or the main circuit that a currently visible subcircuit is contained in) to be initialized and simulated.
Simulation will continue until there no more output value changes are possible or the currently set time limit is reached, whichever comes first. When the simulation ends a yellow simulator bar will appear below the circuit indicating the reason for stopping and the total simulation time.
Long running simulations (unexpected perhaps because of errors in the circuit and too large a time limit) can be stopped by selecting the stop menu item.