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Altera_Forum
Honored Contributor
17 years agoDriving Cyclone III PLL using general purpose input pin
In Cyclone III can I use PLL with input as a general purpose input pin (and not dedicated clock input pin) ? I don't want delay compensation (which I already assume it wont be able to do). I ju...
Altera_Forum
Honored Contributor
17 years agoIn cycloneIII handbook it is mentioned that "Clock control blocks that have inputs driven by internal logic are not able to 'drive' PLL inputs".
What exactly they mean by the term 'drive'? Is it that PLL wont give any output if I use an internal logic driven global clock buffer as an input to the PLL? Or is it just that PLL won't be able to compensate for the delay of the internal logic but will provide the desired output? Or is it something else?