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PDone's avatar
PDone
Icon for Occasional Contributor rankOccasional Contributor
4 years ago

Get warnings when constraining Clock and Generated clocks

am trying to build the following.clock circuits. Although it works, I am not able to get the constraints to work: Basically I have a 20 MHz input clock. This generates an 80 MHz clock which in turn...
sstrell's avatar
sstrell
Icon for Super Contributor rankSuper Contributor
4 years ago

The warnings seem to indicate that the targets of your create_generated_clock commands are incorrect. Did you use the Name Finder (accessed from the timing constraint GUI dialog boxes) to search for the correct targets for get_pins?

The easiest thing to do would be to simply remove the create_generated_clock constraints and use derive_pll_clocks.