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JLee25's avatar
JLee25
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6 years ago

Cyclone 10 GX 3V IO Voltage

Hi community,

I have a new project based on C10 GX and I am debugging the IO problem.

The device is 10GX220YF672, the IO bank 2L was design to interface 3V IO.

I download a counter design to verify the operation, it will toggle every 200 ms.

From waveform, the high level is only 0.9V instead of 3V that I am expected.

What would be the problem?

If my external devices boot earlier than FPGA, will it cause this issue?

Please help!

BRs,

Johnson

5 Replies

    • JLee25's avatar
      JLee25
      Icon for Contributor rankContributor
      6 years ago

      Hi YL,

      Thank you for reply.

      Yes, I did set the IO standard to 3.0V.

      Attached is the qar file for your reference.

      I test 2 boards with this configuration.

      Both show the same status,

      before config, gpio_0 is 3V, led_0 is 0.7V. After config, gpio_0 switch between 3V/ 0 V. led_0 is 0.9V/ 0V.

      Regards,

      Johnson

      • JLee25's avatar
        JLee25
        Icon for Contributor rankContributor
        6 years ago

        Hi YT,

        I just found the clock was not operated properly, amplitude is small..

        I will check it and see if this is the root cause!

        Thank you!

        Regards,

        Johnson

    • JLee25's avatar
      JLee25
      Icon for Contributor rankContributor
      6 years ago

      Hi YT,

      I have a question on the reference file.

      From the table below, it means the external IO pin should be in Tristate during FPGA boot up ?

      If above rule can’t be followed, what will happen to the device?

      And what should I do to prevent this?

      Boot external devices later than FPGA ?

      Please comment.

      Thank you!

      Best Regards,

      Johnson Lee

  • YuanLi_S_Intel's avatar
    YuanLi_S_Intel
    Icon for Regular Contributor rankRegular Contributor
    6 years ago

    Hi Johnson Lee,

    No tri-stated is needed from external pin. During FPGA power up, the pin itself will tri-state for used pin. Meanwhile for unused pin, you will need to do some setting in Quartus to enable tri-stating.

    To do so, go to "Assignments" -> "Device" -> "Device and pin info" -> "Unused pin" -> "As input tri-stated with weak pull up"

    Thank You