Honored ContributorWhen I view the TimeQuest Timing Analyzer - Unconstrained Paths Summary, 4 Unconstrained Clocks appear. The 4 unconstrained nets should not be clocks, but they are being flagged by the tool. How do I remove these nets as appearing as clocks?
Honored ContributorYou're using them to drive registers' clock port.
Ie, you have something like it.process(some_signal) begin
if rising_edge(some_signal) then
...
end if;
end process; I've never seen it report a clock that wasn't being used as one. If I don't know what it's driving, I do a quick:
create_clock -period 1.0 -name test [get_keepers {}] (It may be get_ports, or something like that). Then just report_timing to that new clock. The report is there to help you. There is nothing in .sdc to say, I'm not a clock, you just choose not to constrain it. The Unconstrained Paths report is outside of .sdc constraints, and really just trying to help you identify possible mistakes. I would ignore it if it is a clock and you just don't want to constrain it. (A final option is to put a clock constraint on it that's 1000.0 ns, then do: set_false_path -to [get_clocks test_clk] set_false_path -from [get_clocks test_clk] It should get rid of the info message since it's constrained, and it wont' be analyzed.Honored ContributorYou can also use "derive_clocks -period 10.0" to create the clock for you, and then just report timing to the clock that is created that is driving the clock pin in question.
Honored ContributorGood point.
