TimeQuest: set_max_delay constraint

As Rysc thought, it sounds like you want the constraint on a crossing between asynchronous clock domains. That what the examples below are for on the set_max_delay and set_min_delay on-line help pages.

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# Apply a 10ns max delay between two unrelated clocks

set_max_delay -from [get_clocks clkA] -to [get_clocks clkB] 10.000

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# Apply a 0ns min delay between two unrelated clocks

set_min_delay -from [get_clocks clkA] -to [get_clocks clkB] 0.000

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