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Altera_Forum's avatar
Altera_Forum
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15 years ago

Timing constraints for output clock pin

I'm constraining a synchronous interface to a USB chip, and I've got all the timing constraints in for the data and control lines. Timequest is still listing the output clock itself as unconstrained....
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

as you have realised clk output does not need constraints by itself. to keep timequest happy set false path:

set_false_path -to [get_ports {clkout}]

exception to that if you need to treat it as any nonclk output