Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

Cyclone V Native Phy Transceiver External PPM Detector - rx_clklow and rxfref

Hello

Does anyone know how to enable the rx_clklow and rx_fref clock output ports using the QuartusII 13.1 Megawizard?

I need these ports as per the Cyclone V handbook to be able to implement an external PPM detector i.e. run the native phy in manual lock mode but I can't see in the megawizard how to enable these ports :confused:

Thanks

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    Hello

    Just an update if anyone else stumbles across the same issue. Altera have confirmed it is an error in the transceiver guide documentation and the megawizard is correct i.e. the rx_clklow and rxfref clock outputs are not available on the Cyclone V. However a PPM detector can still be used using the transceiver reference clock input and the recovered clock, either PMA or PCS I guess (care for single or double width modes). This method will need knowledge of the Rx CDR local clock divider, for fixed serial speeds this is straight forward but for multiple serial speeds this will need to have this knowledge to adjust accordingly.

    Not that I have implemented the PPM detector yet so there may be more to this issue to come.