Why does the runt statistics register of Legacy 40/100G Ethernet IP core read back as "X" in simulation? - Why does the runt statistics register of Legacy 40/100G Ethernet IP core read back as "X" in simulation? 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. Custom Fields values: ['novalue'] Troubleshooting FB: 409881; False ['Ethernet'] ['FPGA Dev Tools Quartus® Prime Software Pro'] 16.1.1 16.1 ['Stratix® V GS FPGA', 'Stratix® V GT FPGA', 'Stratix® V GX FPGA'] ['novalue'] ['novalue'] ['novalue']