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The following clock transfers have no clock uncertainty assignment. For more accurate results, apply clock uncertainty assignments or use the derive_clock_uncertainty command.

This critical warning is caused by undefined clock dispersion.
 
As a definition method, there are a command to automatically calculate and a method to calculate and define individually.
 
Cyclone III, Stratix II, Stratix II GX, Arria GX, HardCopy II, Stratix III, and newer devices can automatically calculate clock uncertainty by specifying "derive_clock_uncertainty" in the SDC file am.
 
If calculated and defined separately, use "set_clock_uncertainty".
 
The uncertainty defined by "set_clock_uncertainty" takes precedence over the automatically calculated one.
 
 
* The "derive_clock_uncertainty" command is an SDC command exclusive to Altera.
cannot be read by our company's tools.
If you want to convert the information set by "derive_clock_uncertainty" to "set_clock_uncertainty",
Converted and saved by using "write_sdc -expand".