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Altera_Forum
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12 years ago

Stratix V GX SI Dev Kit - Sometimes no link in Transceiver Toolkit

Hello,

i am using the mentioned board and successfully tested an external transceiver loop with the examples (10312 mbps). I also changed the phy in qsys to fractions of 10312 mbps whichs works as long as the reference clock remains constant.

Now I changed to 6000 mbps with 300 MHz and i get no link, also 12500 mbps with 500 MHz refclk.

In another case I configured the low latency PHY with 8000mbps and 500 MHz and it works without problems.

I changed the refclk to 500 MHz in Qsys/clocks, Qsys/phy and in the sdc-file and of cause i changed the clock on the board.

Does anyone has an idea why some datarates doesn't work, respectivly what I forgot?

Thanks, Micha

4 Replies

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

    It sound weird, the higher rate works fine while lower rate seems problematic. You mentoned it does not work in external loopbavk, how about internal loopback?

    Question: thd first attempt is work on custom phy or native phy?

    can try the non-working rate on low latency phy as seem low latency phy is alqays working?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    --- Quote Start ---

    It sound weird, the higher rate works fine while lower rate seems problematic. You mentoned it does not work in external loopbavk, how about internal loopback?

    --- Quote End ---

    i will take a look.

    --- Quote Start ---

    Question: thd first attempt is work on custom phy or native phy?

    can try the non-working rate on low latency phy as seem low latency phy is alqays working?

    --- Quote End ---

    All rates are made on low latency phy. So, I can't follow you exactly, can you give me some more explainations :)?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    Ok, if all on low latency phy, then it is fine. I though u try on different phy. I am trying to isolate the common failure symptom from your experiments

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

    Maybe u can try the 6gbps using Native Phy, to isolate whether is phy dependent.