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Altera_Forum
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14 years ago

TimeQuest: how do i set_max_skew at lower hierarchy levels?

I've written a module which has an input port requiring a max skew constraint. I.e. i have to constrain the skew on that port to all registers it feeds. The following command will only work i...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

Can you explain why you're using a max skew constraint? Probably the only major real use for an input is when a signal comes in from an asynchronous source and the design over-samples it with registers clocked by different phases of a clock. I've never seen anything done like that internally, and want to make sure you're using it right. Otherwise, find the register that now drives that port and do:

set_max_skew -from [get_keepers REGISTER_NAME_HERE] 0.2