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Altera_Forum
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15 years ago

Negative slack on TimeQuest report

Hello everybody I'm getting some negative slack messages on TimeQuest Timing Analyzer. I have one input clock and one PLL with one clock output in my system. But all of these messages are r...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

Hi,

Check create_clock and derive_pll_clocks commands in sdc file. Have you other contraints? Clock uncertainty?

Is this a setup or hold slack?

Take a look at Quartus timing advisor for some hints to prevent negative slack.

Cris