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LakshmiPriya's avatar
LakshmiPriya
Icon for New Contributor rankNew Contributor
3 years ago
Solved

Intel Cyclone 10 LP FPGA DATA0 and DCLK waveforms

Hi,

What is the expected waveform on DCLK and DATA0. I am seeing something as in the attached files. The waveform looks different for the first few cycles and changes in voltage levels after that. And none of them are square waves. Is this an acceptable waveform?

PS: We have no issues in configuring the FPGA. We are able to read and write well.

Thanks,

Priya

  • FvM's avatar
    FvM
    3 years ago

    Hello,

    particularly the DCLK waveform doesn't look acceptable to me, the slow risetime is at risk to cause double clock edges at the receiver.

    I guess you are performing PS configuration with open drain drivers, e.g. generated by a x51 processor. You should add pull-up resistors to the DCLK and DATA0 lines, or configure push-pull drivers if possible.

    P.S., please use compressed file format, .jpg or png if you want to post graphics.

    Frank

4 Replies

  • FvM's avatar
    FvM
    Icon for Super Contributor rankSuper Contributor
    3 years ago

    Hello,

    particularly the DCLK waveform doesn't look acceptable to me, the slow risetime is at risk to cause double clock edges at the receiver.

    I guess you are performing PS configuration with open drain drivers, e.g. generated by a x51 processor. You should add pull-up resistors to the DCLK and DATA0 lines, or configure push-pull drivers if possible.

    P.S., please use compressed file format, .jpg or png if you want to post graphics.

    Frank

    • LakshmiPriya's avatar
      LakshmiPriya
      Icon for New Contributor rankNew Contributor
      3 years ago

      Yes, I disabled the open drain drive and it looks good now.

  • AqidAyman_Altera's avatar
    AqidAyman_Altera
    Icon for Regular Contributor rankRegular Contributor
    3 years ago

    Thank you for confirming this, Priya. I’m glad that your question has been addressed, I now transition this thread to community support. If you have a new question, feel free to open a new thread to get support from Intel experts. Otherwise, the community users will continue to help you on this thread.


    Have a nice day