Clock Relationships

By default, the Efinity® software assumes that all clocks are related and it analyzes the timing between all clock domains and optimizes all possible paths.

If you set constraints for two clocks, and do not cut the path between them, the software tries to find the tightest clock-to-clock delay requirement between them. If the timer cannot find a common clock period for the two clocks after 1,000 clock cycles, it determines that they are non-expandable. The timer gives these clocks a default constraint of 0.001 ns. If you want to override this default, use the set_max_delay or set_min_delay constraint.