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Table 2-3. 10 Gb+ Ethernet MAC IP Core Input and Output Signals (Continued)
Port Name
Active State
vlan_tag[15:0]
vlan_tag_en
tx_rx_status[4:0]
Multicast Address Filtering Optional Signals
mc_table[63:0]
Timing Specifications
Transmit Interface
When there is a packet ready for transmission, the tx_data_avail is asserted. This signal should stay active until the
MAC asserts the tx_read, after which MAC will ignore the status of tx_data_avail and so the tx_data_avail signal
can be deactivated. The data is available one clock cycle after the MAC asserts the tx_read. The MAC continues
reading the packet until it gets tx_eof active. The tx_eof signal is asserted when the last byte of data is transmitted.
Internally the MAC buffers the data before it starts transmission of a packet. The MAC may stop/continue reading to
maintain the level of the buffer due to factors like IPG insertion and Pause reception. Hence, the tx_read signal can
be deactivated anytime during the transfer. Once the MAC receives tx_eof, the MAC will again start monitoring the
tx_data_avail signal.
Figure 2-7. Transmission of a 64 Data Byte Frame
The tx_staten signal will be asserted once the entire frame is received from the user's interface.
Receive Interface
When the MAC receives the data, it asserts rx_write. The MAC asserts rx_sof when it writes the first byte of data.
The rx_write signal may be deasserted anytime between a packet. In this case the value on rx_data signal is not
valid. The end of a packet is indicated with the assertion of rx_eof signal.
Figure 2-8. Reception of a 64 Data Byte Frame
IPUG39_02.9, December 2010
I/O Type
N/A
Output
The most recently received VLAN tag.
When asserted, indicates that the contents of the vlan_tag bus are valid.
High
Output
This signal is asserted for 3 rxmac_clk periods.
Bit 0 (tx_idle) - When asserted indicates that the transmitter is idle.
Bit 1 (rx_idle) - When asserted indicates that the receiver is idle.
High
Output
Bits[4:2] (link_sts[2:0]) - Contains the RS layer status of the link.
(1=local fault, 2= remote fault, 4=link ok)
N/A
Input
Multicast table
Description
13
10 Gb+ Ethernet MAC IP Core User's Guide
Functional Description
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