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lambert_yu's avatar
lambert_yu
Icon for Contributor rankContributor
5 years ago

About fpll recalibration failure problem of transceiver (simplex tx) under cyclone 10

Hi, I am facing one problem, which is about fpll recalibration failure on cyclone 10 board. Just for same .pof file, no timing violation and different cyclone 10 boards, after POR, the transceiv...
CheepinC_altera's avatar
CheepinC_altera
Icon for Regular Contributor rankRegular Contributor
5 years ago

Hi,


As I understand it, you have some inquiries related to the fPLL recaliration after perform a refclk switching to the fPLL. It seems like the fPLL cal_busy remains high. Just would like to check with you on the following:


1. Just wonder if you have had a chance to try running Modelsim simulation with your design before to isolate any potential functional issue prior to hardware testing?


2. Would you mind to share the detailed steps that you are using to perform the fPLL recalibration? You may cross checked with the section "Fractional PLL Recalibration" in the C10GX XCVR PHY user guide on the steps.


3. Just to check with you if the CLKUSR and fPLL refclk are directly sourced from free-running and stable on-board oscillators?


Please let me know if there is any concern. Thank you.



Best regards,

Chee Pin