The RX MAC
segmented client interface is available when you select Enable
Preamble Passthrough in the parameter editor.
For all data rates, the IP core presents the preamble bits received on the first 8 bytes of the o_rx_mac_data, that is o_rx_mac_data[63:0]. When Remove CRC Bytes is deselected, the CRC bytes are equivalent to the last 4 bytes of data while in the segment containing the EOP o_rx_endofpacket is asserted.
| 100GE/200GE/400GE o_rx_mac_data |
40GE/50GE o_rx_mac_data |
10GE/25GE o_rx_mac_data |
MAC Field | Note |
|---|---|---|---|---|
| [7:0] | [7:0]' | [7:0]'' | Preamble [7:0] | 0x55 |
| [15:8] | [15:8]' | [15:8]'' | Preamble [15:8] | 0x55 |
| [23:16] | [23:16]' | [23:16]'' | Preamble [23:16] | 0x55 |
| [31:24] | [31:24]' | [31:24]'' | Preamble [31:24] | 0x55 |
| [39:32] | [39:32]' | [39:32]'' | Preamble [39:32] | 0x55 |
| [47:40] | [47:40]' | [47:40]'' | Preamble [47:40] | 0x55 |
| [55:48] | [55:48]' | [55:48]'' | Preamble [55:48] | 0x55 |
| [63:56] | [63:56]' | [63:56]'' | Preamble [63:56] | 0xD5 (SFD) |
| [71:64] | [71:64]' | [7:0]' | Dest Addr[47:40] | |
| [79:72] | [79:72]' | [15:8]' | Dest Addr[39:32] | |
| [87:80] | [87:80]' | [23:16]' | Dest Addr[31:24] | |
| [95:88] | [95:88]' | [31:24]' | Dest Addr[23:16] | |
| [103:96] | [103:96]' | [39:32]' | Dest Addr[15:8] | |
| [111:104] | [111:104]' | [47:40]' | Dest Addr[7:0] | |
| [119:112] | [119:112]' | [55:48]' | Src Addr[47:40] | When you turn on Source Address Insertion, contents are replaced by txmac_saddr unless i_tx_skip_crc is high. |
| [127:120] | [127:120]' | [63:56]' | Src Addr[39:32] | |
| [135:128] | [7:0] | [7:0] | Src Addr[31:24] | |
| [143:136] | [15:8] | [15:8] | Src Addr[23:16] | |
| [151:144] | [23:16] | [23:16] | Src Addr[15:8] | |
| [159:152] | [31:24] | [31:24] | Src Addr[7:0] | |
| [167:160] | [39:32] | [39:32] | Length/Type[15:0] | |
| [175:168] | [47:40] | [47:40] | Length/Type[7:0] | |
| […:176] | [127:48] | [63:48] | … |