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Ad13's avatar
Ad13
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5 years ago

Cyclone 10GX VREF pin

I have a custom board using Cyclone 10GX085YU484 and I cannot program the device and it does not appear on the JTAG chain. I have left the VREF pins floating (VREF pins (T7, T13, J15 and F12) ). The datasheet says these should be connected to VCCIO or GND. Could this error stop the FPGA from running up and being programmed (visible on JTAG)? Same with VREFP_ADC and VREFN_ADC (floating and should be GND). Thanks.

4 Replies

  • AminT_Intel's avatar
    AminT_Intel
    Icon for Regular Contributor rankRegular Contributor
    5 years ago

    Hello,

    I believe this could be because of connection error. Can you confirm if your device is connected to your computer? Could you use other plugs to confirm that?

    Thank you.

    • Ad13's avatar
      Ad13
      Icon for New Contributor rankNew Contributor
      5 years ago

      Hi, yes all connected to Quartus and the Quartus programmer.

      I have tried multiple programmers(download cables), including the official Altera USB Blaster 2. I am able to program other devices from Quartus with the same set up and download cable fine.

      Would floating VREF pins cause this problem?

      Thanks.

      • L982123's avatar
        L982123
        Icon for New Contributor rankNew Contributor
        4 years ago

        Hi, were the floating VREF pins causing your problem? I am seeing the same issue and VREFs also floating.