Article ID: 000075370 Content Type: Troubleshooting Last Reviewed: 12/23/2022

Why does the runt statistics register of Legacy 40/100G Ethernet IP core read back as "X" in simulation?

Environment

  • Intel® Quartus® Prime Pro Edition
  • Ethernet
  • BUILT IN - ARTICLE INTRO SECOND COMPONENT
    Description

    Due to a change in runt handling behavior in the Intel® Quartus® Prime Software v16.1, the runt statistics register might read back as "X" in simulation in the Legacy 40/100G Ethernet Megacore® function.

    Normal core behavior is not affected, but when running the KR4 example testbench, the following messages might be seen:

    # DUT 1 Sent                1027 packets
    # DUT 2 Received           1027 packets
    # Runts in RX data
    # DUT 2 Sent                1027 packets
    # DUT 1 Received            1027 packets
    # Runts in RX data

    These messages can be safely ignored.

    Resolution

    This problem is fixed starting with the Intel® Quartus® Prime Pro Edition Software version 16.1.1.

    Related Products

    This article applies to 3 products

    Stratix® V GX FPGA
    Stratix® V GS FPGA
    Stratix® V GT FPGA