During simulation of the 40- and 100-Gbps Ethernet MAC and PHY MegaCore Function, l8_rx_fcs_error goes to 'X' when l8_rx_fcs_valid is '1' - During simulation of the 40- and 100-Gbps Ethernet MAC and PHY MegaCore Function, l8_rx_fcs_error goes to 'X' when l8_rx_fcs_valid is '1' Description Due to a problem in the 40- and 100-Gbps Ethernet MAC and PHY MegaCore ® Function, l8_rx_fcs_error may go to “X” when l8_rx_fcs_valid goes to '1'. Resolution To work around this problem, upgrade to the Quartus ® II software version 13.1. Custom Fields values: ['novalue'] Troubleshooting novalue False ['novalue'] ['FPGA Dev Tools Quartus II Software'] 13.1 13.0 ['Arria® V GZ FPGA', 'Stratix® IV GT FPGA', 'Stratix® V GS FPGA', 'Stratix® V GT FPGA', 'Stratix® V GX FPGA'] ['novalue'] ['novalue'] ['novalue']