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NuvKFC's avatar
NuvKFC
Icon for Contributor rankContributor
3 years ago
Solved

How to constraint max skew between two net or balance the delay between two net?

I have two end point (two path) that need to balance the delay. The design is as follows. Path1: PAD1-->clock of module A: clock_a Path2: PAD2-->data of module A: data_a How t...
Nurina's avatar
Nurina
Icon for Regular Contributor rankRegular Contributor
3 years ago

Hi,


Any reason why you put both paths in one constraint?

Did you try two separate constraint like so:

set_max_skew 1.0 -from [get_ports {PAD1}] \

-to [get_nets {A|clock_a}]]

set_max_skew 1.0 -from [get_ports {PAD2}] \

-to [get_nets {A|data_a}]]


Regards,

Nurina


NuvKFC's avatar
NuvKFC
Icon for Contributor rankContributor
3 years ago

Hi Nurina

Thank you, Nurina, very much.

The path1 is from PAD1 to clock_a of module A.

The path2 is from PAD2 to data_a of module A. The data_a is one bit data.

I hadn't tried to separate constraint. I will try it. And how to report the skew between those two paths?

I'm confused that separating the constraint can balance those two paths?

Those two paths aren't in the same group like data bus, data[7:0].

I'm confusing how to balance the delay of those two paths.

Thank you very much