220.127.116.11.1. Order of Transmission
The IP core transmits bytes on the Ethernet link starting with the preamble and ending with the FCS in accordance with the IEEE 802.3 standard. Transmit frames the IP core receives on the client interface are big‑endian. Frames the MAC sends to the PHY on the XGMII/CGMII between the MAC and the PHY are little‑endian; the MAC TX transmits frames on this interface beginning with the least significant byte.
For example, the destination MAC address includes the following six octets AC-DE-48-00-00-80. The first octet transmitted (octet 0 of the MAC address described in the 802.3 standard) is AC and the last octet transmitted (octet 7 of the MAC address) is 80. The first bit transmitted is the low-order bit of AC, a zero. The last bit transmitted is the high order bit of 80, a one.
The preceding table and the following figure show that in this example, 0xAC is driven on DA5 (DA[47:40]) and 0x80 is driven on DA0 (DA[7:0]).
Destination Address is the broadcast/multicast bit (a type bit), and Destination Address is a locally administered address bit.
The destination address and source address bytes follow the preamble pass-through in the same order as in the case without preamble pass-through.