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KRoma6's avatar
KRoma6
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5 years ago

LVDS SERDES using external PLL from IOPLL

Hello,

I am using the LVDS SERDES IP with external PLL provided by the IOPLL. I configured the IOPLL as recommended in the LVDS SERDES IP for Cyclone 10 GX but I am getting an error:

"ext_<clock name> has a export signal, but <clock name> does not."

This is true for all three clock input from the IOPLL to the LVDS SERDES.

Any idea on how to fix this?

3 Replies

  • JonWay_altera's avatar
    JonWay_altera
    Icon for Frequent Contributor rankFrequent Contributor

    Hi @KRoma6

    Did you use the PLL setting: Access to PLL LVDS_CLK/LOADEN output port

    If yes, could you try this on the RTL instead of the Qsys platform?

    Lets narrow down if this is a Qsys platform connectivity issue or an LVDS IP issue.

    • KRoma6's avatar
      KRoma6
      Icon for New Contributor rankNew Contributor

      Hi JonWay,

      Yes I tried both options for the "Access to PLL LVDS_CLK/LOADEN output port": <"LOADEN 0" and "LOADEN 0 & 1">.

      So you want to export these signals and connect them within a module?

      • JonWay_altera's avatar
        JonWay_altera
        Icon for Frequent Contributor rankFrequent Contributor

        Generate HDL for both the LVDS and PLL IP. Create a top RTL file and instantiate both IPs there. Connect them together by RTL coding. Check if the problem is still there or not.