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Altera_Forum
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15 years ago

pll reconfiguration on cycloneIII

Dear all, My requirement is to have a pll that can be reconfigured on fly to 2 different frequency 100 MHz and 50 MHz. My input clock is 5MHz. I am using 2 ROM having the settings for the 2 fre...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

You're expecting me to read the whole post?

As for the core issue, you state that the PLL lock signal goes high but the PLL does not lock. What symptoms are you seeing to state it's not locking? Is it not outputing a clock, or is the clock drifting, or something like that? Also, does the PLL work if you don't have any reconfiguration(i.e. a fundamental locking issue) or does it occur when adding the dynamic logic(i.e. something going wrong there)?