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Altera_Forum
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13 years ago

What is mean of rhis critical warning and how to handle it?

When I compile my design which use two plls in a EP4CE55F device, I have a cirtical warning as following: Critical Warning (176598): PLL "DSP_System:dsp_system|HistoComputeScene:histocomputesce...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

If you cannot change the source of the clock driving the PLL due to fixed pins, keep in mind that this is a warning, not an error. If you run "derive_clock_uncertainty" in TimeQuest and look at the uncertainty on the output clocks from the PLL, if you can live with this level of uncertainty, then you can ignore this warning.