A logic option that allows the Compiler to choose the signal that feeds the most clock inputs to flipflops as a global clock signal that is made available throughout the device on the global routing paths.

This option is ignored if it is assigned to anything other than a design entity. If you want to prevent the Compiler from automatically selecting a particular signal as global clock, set the Global Signal option to Off on that signal. This option is available for all Altera^® devices supported by the Quartus^® II software.