Xilinx LOGICORE UG144 - Manual (Page 83)

1-Gigabit Ethernet MAC v8.5 User Guide www.xilinx.com 83
UG144 April 24, 2009
Using the Optional Management Interface R
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The Address Filter can be programmed to respond to four separate additional addresses
stored in an address table in the Address Filter.
Table 8-10 and Table 8-11 describe how the
contents of the address table are set.
The contents of the Address Filter mode register are described in Table 8-12 .
Writing and Reading to and from the Configuration Registers
Writing to the configuration registers through the management interface is shown in
Figure 8-1 . When accessing the configuration registers (when host_addr[9] = ‘1’ and
host_miim_sel = ‘0’), the upper bit of host_opcode functions as an active low write
enable signal. The lower host_opcode bit is a don’t care bit.
Table 8-10: Address Table Configuration Word 0
Bits
Default
Value
Description
31–0 All 0s MAC Address[31:0].
The address is ordered so the first byte received is the
lowest positioned byte in the register; for example, a MAC
address of AA-BB-CC-DD-EE-FF would be stored in
Address[47:0] as 0xFFEEDDCCBBAA.
Table 8-11: Address Table Configuration Word 1
Bits
Default
Value
Description
15–0 All 0s MAC Address[47:32].
17–16 All 0s The location in the address table that the MAC address is
to be written to or read from. There are up to 4 entries in
the table (Location 0 to 3).
22–18 N/A Reserved
23 0 Read not write This bit is set to ‘1’ to read from the address
table. If it is set to ‘1,’ the contents of the table entry that is
being accessed by the bits 17-16 will be output on the
hostrddata bus in consecutive cycles (least significant
word first). If it is set to ‘0,’ the data on bits 15-0 is written
into the table at the address specified by bits 17-16.
31–24 N/A Reserved
Table 8-12: Address Filter Mode
Bits
Default
Value
Description
30–0 N/A Reserved
31 0 Promiscuous Mode If this bit is set to ‘1,’ the Address Filter
operates in promiscuous mode. All frames are passed to
the receiver client, regardless of the destination address.