Client-Supplied Fcs Passing; Vlan Tagged Frames; Figure 5-3: Frame Reception With In-Band Fcs Field; Figure 5-4: Reception Of A Vlan Tagged Frame - Xilinx LogiCORE IP MAC v8.5 User Manual

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Client-Supplied FCS Passing

If the GEMAC core is configured to pass the FCS field to the client (see
Registers," on page
inserted into the frame to meet Ethernet minimum frame length specifications will be left
intact and passed to the client.
Even though the FCS is passed up to the client, it is also verified by the GEMAC core, and
rx_bad_frame asserted if the FCS check fails.

VLAN Tagged Frames

Figure 5-4
is passed to the client so that the frame may be identified as VLAN tagged. This is followed
by the Tag Control Information bytes, V1 and V2. More information on the interpretation
of these bytes may be found in IEEE 802.3-2005 standard.
rx_good_frame
rx_bad_frame
42
-- DISCONTINUED PRODUCT --
78), this is handled as shown in
gmii_rx_clk
rx_data[7:0]
rx_data_valid
rx_good_frame
rx_bad_frame

Figure 5-3: Frame Reception with In-Band FCS Field

illustrates the reception of a VLAN tagged frame (if enabled). The VLAN frame
gmii_rx_clk
rx_data[7:0]
rx_data_valid

Figure 5-4: Reception of a VLAN Tagged Frame

www.xilinx.com
Chapter 5: Using the Client Side Data Path
Figure
DA SA L/T
81 00V1V2
DA SA VLAN
tag
1-Gigabit Ethernet MAC v8.5 User Guide
"Configuration
5-3. In this case, any padding
DATA FCS
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