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cjak's avatar
cjak
Icon for New Contributor rankNew Contributor
7 days ago
Solved

Constraining an unclocked output?

Hi, I am trying to achieve timing closure, but have trouble constraining outputs that is not referenced to an external clock. Do I have to define a false path for each output?
Timing
  • FvM's avatar
    FvM
    6 days ago

    Hi,

    to declare all IO as asynchronous

    set_false_path -from [all_inputs]

    set_false_path -to [all_outputs]

sstrell's avatar
sstrell
Icon for Super Contributor rankSuper Contributor
6 days ago

If they're completely asynchronous outputs, yes, you would false path them.  You can use wildcards in your target for set_false_path if there are a lot of them.

KennyT_altera's avatar
KennyT_altera
Icon for Super Contributor rankSuper Contributor
6 days ago

sstrell is right, do you have further queries?