For the FROM TO constraint, two TIMEGRPs must be created: one for the destination elements and one for the source elements. To exclude a signal(s) from either theTIMEGRP for the FROM TO constraint, you can use an EXCEPT command.
For example, the syntax would look like the following:
If you must apply a FROM TO TIG constraint, make sure that the TIMESPEC line contains the TIG notifier as follows:
TIMESPEC "TS_constraintA" = FROM "new_srcgrp" TO "new_destgrp" TIG;