Xilinx Virtex-4 - Page 68

68 www.xilinx.com Embedded Tri-Mode Ethernet MAC User Guide
UG074 (v2.2) February 22, 2010
Chapter 3: Client, Host, and MDIO Interfaces
R
Receiver Statistics Vector
RX_STATISTICS_VECTOR contains the statistics for the frame received. The vector is
driven synchronously by the receiver clock, CLIENTEMAC#RXCLIENTCLKIN, following
frame reception. The bit field definition for the receiver statistics vector is defined in
Table 3-5.
The RX_STATISTICS_VECTOR is a 27-bit wide vector, and is internal in the receive engine.
This vector is muxed out to a seven-bit wide signal EMAC#CLIENTRXSTATS[6:0] as
shown in Figure 3-35.
20 TX_DEFERRED
Asserted if transmission of the frame was
deferred.
19 VLAN_FRAME
Asserted if the previous frame contains a VLAN
identifier in the LT field when transmitter VLAN
operation is enabled.
[18:5] FRAME_LENGTH_COUNT
The length of the previous frame in number of
bytes. The count sticks at 16383 for jumbo frames
larger than this value. Stops at 16383.
4 CONTROL_FRAME
Asserted if the previous frame has the special
Ethernet MAC control type code
88-08 in the LT field.
3 UNDERRUN_FRAME
Asserted if the previous frame contains an
underrun error.
2MULTICAST_FRAME
Asserted if the previous frame contains a
multicast address in the destination address field.
1 BROADCAST_FRAME
Asserted if the previous frame contains a
broadcast address in the destination address
field.
0 SUCCESSFUL_FRAME
Asserted if the previous frame is transmitted
without error.
Notes:
1. Bits [28:20] of TX_STATISTICS_VECTOR are valid for half-duplex mode only.
Table 3-4: Bit Definitions for the Transmitter Statistics Vector (Cont’d)
TX_STATISTICS_VECTOR Name Description
Figure 3-35: Receiver Statistics MUX Timing
[6:0] [13:7] [20:14] [26:21]
CLIENTEMAC#RXCLIENTCLKIN
RX_STAT ISTICS_VALID
(internal signal)
RX_STAT ISTICS_VECTOR[26:0]
(internal signal)
EMAC#CLIENTRXSTATSVLD
EMAC#CLIENTRXSTATS[6:0]
ug074_3_37_080805
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