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Hi, there:=20
My clk_4m is generated from clk_12m through a divide_by_3 state = machine... And I feed clk_4m into a BUFG also...I estimate the time from rising = edge of=20 clk_12m to clk_4m is 3.6 ns...Can I write these two constraints?=20
NET "clk_12m" TNM =3D "clk_12m"; TIMESPEC "TS_clk_12m" =3D PERIOD "clk_12m" 83.3 ns HIGH 50 %; NET "clk_4m" TNM =3D "clk_4m"; TIMESPEC "TS_clk_4m" =3D PERIOD "clk_4m" TS_clk_12m / 3 PHASE + 3.6 ns;
Thanks.=20 Kelvin