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Jodok's avatar
Jodok
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2 years ago

Cyclone V: reaching RGMII Data to Clock output skew of +/- 500ps

What is best practice to reach the 500ps Data to Clock output Skew of RGMII specification v2.0 on a Cyclone V? Trying synthesizing a TSE MAC with RX-Clock to TX-Clock loopback fails because of timin...
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ShengN_altera's avatar
ShengN_altera
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2 years ago

Hi,


Seems like that's the phy delay lacking which causes the violation.


Is the timing pass after adding the phy delay?


  • Jodok's avatar
    Jodok
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    2 years ago

    Dear Sheng,

    No, unfortunatly the timing is still bad.

    Please, where do you think is the phy-delay lacking?

    I thought I considered the phy-delay in the constraints with (tPeriod/2 - tPHYDELAY) Please have a look at Cell O20;O21 in the Excel.

    Greetings