Forum Discussion
Altera_Forum
Honored Contributor
Honored ContributorConstraining PLL in TimeQuest
Hello, I was waondering how to use derive_pll_clocks comand in TimeQuset. TimeQuest can't reflect new frequency. I did... 1.I grenarated SDC File from QSF File. 2.I changed input...
Altera_ForumHonored Contributor
Honored ContributorHi wat_arg,
You can try the -create_base_clocks option of derive_pll_clocks. With the option, derive_pll_clocks creates the PLL input clock ('clk' in your case) if the clock is not defined. Of course you need to comment out the input clock definition. Here are the updated SDC constraints: derive_pll_clock -create_base_clocks # create_clock -period "6.666 ns" -name {clk} {clk} ;# commented out
