Forum Discussion

HBhat2's avatar
HBhat2
Icon for Contributor rankContributor
6 years ago

Experiment with S-10 Transceiver IO Terminations

Hi, I am performing some experiment with S-10 SoC Dev kit (L-tile). I am using FMC loopback cards to check the behavior of SERDES so as to use for my final requirement. My goal is to connect a dev...
CheepinC_altera's avatar
CheepinC_altera
Icon for Regular Contributor rankRegular Contributor
6 years ago

Hi HPB,

Regarding the TX analog settings, apart from the VOD and pre-emphasis, there is another parameter - slew rate control. However, based on my understanding, generally VOD and pre-emphasis would have more significant impact to signal integrity. In your case, I think you would need to look into using matching impedance since the auto-sweep is unable to get any acceptable BER for you. Sorry for the inconvenience.

Please let me know if there is any concern. Thank you.

Best regards,

Chee Pin

  • HBhat2's avatar
    HBhat2
    Icon for Contributor rankContributor
    6 years ago

    Hi Chee Pin,

    Thank you for hinting towards slew rate. Let me check that as well.

    I think this is one of the aspect which I missed. In all my previous tests, Slew rate control was set to '0'. Just now I gone through the XCVR user guide and found that Slew rate control is set o 5 for Gen2 PIPE and Gen3 PIPE.

    Also, I want to know the definition of values of slew rate control ( 0 to 5). i.e. what is the meaning of slew rate control = 0, 1 etc..

    With regards,

    HPB

    • CheepinC_altera's avatar
      CheepinC_altera
      Icon for Regular Contributor rankRegular Contributor
      6 years ago
      Hi, Regarding the slew rate control settings, as I understand it from the user guide, 0 = slowest and 5 = fastest. There seems to be no specific specs in term of seconds in the user guide. Thank you. Best regards, Chee Pin