Forum Discussion
Altera_Forum
Honored Contributor
Honored ContributorLE carry chain
I'm trying to implement LE carry chain using low level primitives. L_0:LCELL
PORT MAP (
in0,out0
);
D_0:DFFEAS
PORT MAP(
d=>out0,
q=>delay(0),
c...
Altera_ForumHonored Contributor
Honored ContributorYes, ModelSim produces X output for the complete range, that could be possibly affected by a timing violation. This way it marks the result as unknown depending on varying device parameters. In a real device, the result would be determined depending on individual timing parameters, except for a short jitter ruled uncertainty zone, including a certain prohabilty of metastable states.
I'm not aware of a method to change ModelSim behaviour in this regard.
