1. About the 25G Ethernet Intel FPGA IP
2. Getting Started
3. 25G Ethernet Intel FPGA IP Parameters
4. Functional Description
5. Reset
6. Interfaces and Signal Descriptions
7. Control, Status, and Statistics Register Descriptions
8. Debugging the Link
9. 25G Ethernet Stratix® 10 Intel® FPGA IP User Guide Archives
10. Document Revision History for the 25G Ethernet Stratix® 10 Intel® FPGA IP User Guide
6.1. TX MAC Interface to User Logic
6.2. RX MAC Interface to User Logic
6.3. Transceivers
6.4. Transceiver Reconfiguration Signals
6.5. Avalon® Memory-Mapped Management Interface
6.6. PHY Interface Signals
6.7. 1588 PTP Interface Signals
6.8. Miscellaneous Status and Debug Signals
6.9. Reset Signals
4.1.4.1. IP Core Preamble Processing
If you turn on Enable preamble passthrough in the parameter editor, the RX MAC forwards preamble bytes. The TX MAC requires the preamble bytes to be included in the frames at the Avalon® Streaming interface.
If you turn off Enable preamble passthrough, the IP core removes the preamble bytes. l1_rx_startofpacket is aligned to the MSB of the destination address.
Note that a single parameter in the 25G Ethernet Intel FPGA IP parameter editor turns on both RX and TX preamble passthrough.