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anonimcs's avatar
anonimcs
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2 years ago
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Enable on-chip termination for Differential Transceiver clocks

Hi all, I was wondering what .qsf assignments I would need to enable on-chip termination for my differential transceiver clocks. The target device is an Arria10. When I tried using the line below, I...
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  • FvM's avatar
    FvM
    12 months ago

    Hi,

    as far as I understand you are still searching for valid .qsf entry for transceiver clock input termination.

    Valid settings are listed in this document: https://www.intel.com/content/www/us/en/docs/programmable/683296/24-3.html
    As far as I see, the settings are the same for previous Quartus Pro versions.

    The option for transceiver reference clock termination is XCVR_A10_REFCLK_TERM_TRISTATE

    allowed values are TRISTATE_OFF and TRISTATE_ON

    TRISTATE_OFF corresponds to 100 ohm differential termination.

    Some confusion is caused by the fact, that Quartus Std. uses a different option name
    XCVR_REFCLK_PIN_TERMINATION

    values are AC_COUPLING, DC_COUPLING_EXTERNAL_RESISTOR and DC_COUPLING_INTERNAL_100_OHMS

    See: https://www.intel.com/content/www/us/en/docs/programmable/683084/current/settings-file-reference-manual.html

    To check which termination has been actually implemented, you can review QPP fitter report/Plan Stage/Input Pins.


    Regards
    Frank

  • anonimcs's avatar
    anonimcs
    Icon for Contributor rankContributor
    12 months ago

    Hi,

    There are no descriptions about the meaning of the values we can use for the termination assignment. What are those values and more importantly how can I specify a Diff. 100 Ohm syntax using those values ?