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Altera_Forum
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15 years ago

what can I do to delay the source

I'm using the megafunction ALTDDIO as a receiver which requires the input data to be centered aligned to the rising and falling source clock. Unfortunely I have learned the source and data are going ...
Altera_Forum's avatar
Altera_Forum
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15 years ago

Aside from using time constraints (which I wouldn't recommend) I think using a PLL is your best bet, assuming the multiple clocks you are talking about are at known discrete frequencies.

You can use multipliers within the same PLL to generate the derived clocks, specifying different phases as desired (you can have 5 different outputs with 5 phases and frequencies from the same PLL on the Cyclone II for example) Otherwise, you can use clock switching (mentioned in the Altera PLL Megafunction User Guide.)