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Altera_Forum
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9 years ago

PLL clock switchover with automatic derivation of PLL clocks is not working

Hi all, I'm using a Cyclone V and need to switch between two input clocks. The clocks have the same parameters. I adhered to the timequest cookbook which says the following: #create a 10...
Altera_Forum's avatar
Altera_Forum
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9 years ago

How are you selecting the input clock to the PLL? That logic may be why derive_pll_clocks isn't working. Can you post the HDL code? Normally, clock inputs make direct connections to PLLs.