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Altera_Forum
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9 years ago

Cyclone 5 PLLs

Is there a programatic way to re-configure the on chip PLLs? I don't mean loading a new .mif file, but rather having the embedded OS calculate the constants required to re-load the PLL for a differ...
Altera_Forum's avatar
Altera_Forum
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9 years ago

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Is there a programatic way to re-configure the on chip PLLs? I don't mean loading a new .mif file, but rather having the embedded OS calculate the constants required to re-load the PLL for a different frequency?

I would like to have the embedded OS be able to generate a wider range of frequencies off of the base clock.

Thanks,

Jon Herr

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Hi Jon,

If you are referring to the HPS PLL, you can refer to the chapter "Clock Manager" in the Technical reference manual here:

https://www.altera.com/en_us/pdfs/literature/hb/cyclone-v/cv_5v4.pdf

Check the "Hardware-Managed and Software-Managed Clocks" section for details on the clock management.