GTS Ethernet Intel® FPGA Hard IP User Guide

ID 817676
Date 8/05/2024
Public
Document Table of Contents

4.4.2.1. Receive Ethernet Frame on the RX MAC Avalon Streaming Client Interface with Preamble Passthrough Disabled

Sample the Ethernet Frame Destination Address on the first clock cycle of the RX MAC Avalon Streaming Client Interface when the Preamble Disabled is turned off. Refer to the table below for details.

Table 30.  RX MAC Field Positions in o_rx_data with Preamble Passthrough Disabled
i_clk_rx(cycle) o_rx_data MAC Field Description
1->D0 [63:56] Dest Addr[47:40] The first octet of the Destination Address, follows Start Frame Delimiter (SFD).
  [55:48] Dest Addr[39:32] -
  [47:40] Dest Addr[31:24] -
  [39:32] Dest Addr[23:16] -
  [31:24] Dest Addr[15:8] -
  [23:16] Dest Addr[7:0] -
  [15:8] Src Addr[47:40] -
2->D1 [7:0] Src Addr[39:32] -
[63:56] Src Addr[31:24] -
[55:48] Src Addr[23:16] -
[47:40] Src Addr[15:8] -
[39:32] Src Addr[7:0] -
[31:24] Length/Type[15:8] -
[23:16] Length/Type[7:0] -
[15:0] -

The byte order of the data is the same as the TX MAC SOP-Aligned Client interface – the first byte of the packet received was the MSB of the bus.

  • The bit order of the data also matches the TX MAC SOP-Aligned Client interface.
  • For 10GE/25GE, the first bit of the first received byte is bit 56.
Note: The Ethernet header arrives over two clock cycles for the 10GE/25GE interfaces.