NET "sys_clk_in" TNM_NET = "sys_clk_in";
TIMESPEC "TS_sys_clk_in" = PERIOD "sys_clk_in" 10 ns HIGH 50 %;
OFFSET = IN 8 ns BEFORE "sys_clk_in"  ;
OFFSET = OUT 12 ns AFTER "sys_clk_in"  ;