132 www.xilinx.com Ethernet 1000BASE-X PCS/PMA or SGMII v9.1
UG155 March 24, 2008
Chapter 9: Configuration and Status
R
1.10 100BASE-T2 Full
Duplex
Always returns a ‘0’ for this bit since
100BASE-T2 Full Duplex is not supported
returns 0 0
1.9 100BASE-T2 Half
Duplex
Always returns a ‘0’ for this bit since
100BASE-T2 Half Duplex is not supported
returns 0 0
1.8 Extended Status Always returns a ‘1’ for this bit to indicate
the presence of the Extended Register
(Register 15)
returns 1 1
1.7 Unidirectional Ability Always returns 1, writes ignored returns 1 1
1.6 MF Preamble
Suppression
Always returns a ‘1’ for this bit to indicate
that Management Frame Preamble
Suppression is supported
returns 1 1
1.5 Auto- Negotiation
Complete
Ignore this bit because Auto-Negotiation
is not included.
returns 1 1
1.4 Remote Fault Always returns a ‘0’ for this bit because
Auto-Negotiation is not included.
returns 0 0
1.3 Auto- Negotiation
Ability
Ignore this bit because Auto-Negotiation
is not included.
returns 0 0
1.2 Link Status
1
1 = Link is up
0 = Link is down
Latches '0' if Link Status goes down.
Clears to current Link Status on read.
See table note for Link Status behavior.
read only
self
clearing
on read
0
1.1 Jabber Detect Always returns a ‘0’ for this bit since
Jabber Detect is not supported
returns 0 0
1.0 Extended Capability Always returns a ‘0’ for this bit since no
extended register set is supported
returns 0 0
1. When high, the link is valid: synchronization of the link has been obtained and Auto-Negotiation (if present and enabled) has
completed.
When low, a valid link has not been established. Either link synchronization has failed or Auto-Negotiation (if present and
enabled) has failed to complete.
Regardless of whether Auto-Negotiation is enabled or disabled, there can be some delay to the deassertion of this signal
following the loss of synchronization of a previously successful link. This is due to the Auto-Negotiation state machine which
requires that synchronization is lost for an entire link timer duration before changing state. For more information, see the 802.3
specification.
Table 9-15: Status Register (Register 1) (Continued)
Bit(s) Name Description Attributes
Default
Value
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