Data-to-Date Setup Check:
A data-to-data setup check specifies how early the constrained signal (the "-to" or pin) must arrive relative to the related pin (the "-from" pin). It is specified in terms of a positive leading offset relative to the related pin – this means positive values indicate a leftward, or "leading," direction on a waveform diagram. If the constrained signal arrives too late relative to the check, it will fail.
Data-to-Date Setup Check:
A data-to-data setup check specifies how early the constrained signal (the "-to" or pin) must arrive relative to the related pin (the "-from" pin). It is specified in terms of a positive leading offset relative to the related pin – this means positive values indicate a leftward, or "leading," direction on a waveform diagram. If the constrained signal arrives too late relative to the check, it will fail.
Commands define data to data setup check:
set_data_check -from U6/DAT -to U6/EN -setup 1.0
Data-to-Date Hold Check:
A data-to-data hold check specifies how late the constrained signal must arrive relative to the related pin. It is specified in terms of a positive trailing offset relative to the related pin – this means positive values indicate a rightward, or "trailing," direction on a waveform diagram. If the constrained signal arrives too early relative to the check, it will fail.
Commands define data to data hold check:
set_data_check -from U6/DAT -to U6/EN -hold 1.0
In all cases, an increasingly positive check value represents tighter (more conservative) constraint behavior, and an increasingly negative check value represents more relaxed constraint behavior.