The model contains N integrators x[i] with different integration rates. When each state values crosses the value of one, a when clause is triggered, switching the corresponding boolean e[i] from false to true.
The integration rates are such that if StopTime = 1, then M-1 equally spaced events are triggered during the simulation.
Summing up, the model contains N zero-crossing functions and generates M-1 state events if the simulation lasts 1 second.