ICS1893CF Data Sheet - Release
Chapter 6 Functional Blocks
6.2.3 Auto-Negotiation: Remote Fault Signaling
If the remote link partner detects a fault, the ICS1893CF reports the remotely detected fault to the STA by
setting to logic one the Remote Fault Detected bit(s), 1.4, 5.13, 17.1, and 19.13. In general, the reception
of a remote fault means that the remote link partner has a problem with the integrity of its receive channel.
Similarly, if the ICS1893CF detects a link fault, it transmits a remote fault-detected condition to its remote
link partner. In this situation, the ICS1893CF sets to logic one the Auto-Negotiation Link Partner Ability
Register’s Remote Fault Indication bit (bit 4.13).
For details, see Section 7.14.3, “Remote Fault (bit 19.13)” and Section 7.3.9, “Remote Fault (bit 1.4)”.
6.2.4 Auto-Negotiation: Reset and Restart
If enabled, execution of the ICS1893CF auto-negotiation process occurs at power-up and upon
management request. There are two primary ways to begin the Auto-Negotiation state machine:
• ICS1893CF reset
• Auto-Negotiation Restart
6.2.4.1 Auto-Negotiation Reset
During a reset, the ICS1893CF initializes its Auto-Negotiation sublayer modules to their default states.
(That is, the Auto-Negotiation Arbitration State Machine and the Auto-Negotiation Progress Monitor reset to
their idle states.) In addition, the Auto-Negotiation Progress Monitor status bits are all set to logic zero. This
action occurs for any type of reset (hardware reset, software reset, or power-on reset).
6.2.4.2 Auto-Negotiation Restart
As with a reset, during an Auto-Negotiation restart, the ICS1893CF initializes the Auto-Negotiation
Arbitration State Machine and the Auto-Negotiation Progress Monitor modules to their default states.
However, during an Auto-Negotiation Restart, the Auto-Negotiation Progress Monitor status bits maintain
their current state. Only three events can alter the state of the Auto-Negotiation Progress Monitor status
bits after a Restart: (1) an STA read operation, (2) a reset, or (3) the Auto-Negotiation Arbitration State
Machine progressing to a higher state or value.
The Auto-Negotiation Progress Monitor Status bits change only if they are progressing to a state with a
value greater than their current state (that is, a state with a higher logical value than that of their current
state). For a detailed explanation of these bits and their operation, see Section 6.2.5, “Auto-Negotiation:
Progress Monitor”.
After the Auto-Negotiation Arbitration State Machine reaches its final state (which is Auto-Negotiation
Complete), only an STA read of the QuickPoll Detailed Status Register or an ICS1893CF reset can alter
these status bits.
Any of the following situations initiates a restart of the ICS1893CF Auto-Negotiation sublayer:
• A link failure
• In software mode:
– Writing a logic one to the Control Register’s Restart Auto-Negotiation bit (bit 0.9), which is a self-
clearing bit.
– Toggling the Control Register’s Auto-Negotiation Enable bit (bit 0.12) from a logic one to a logic zero,
and back to a logic one.
ICS1893CF, Rev. F, 03/01/07
Mar. 2007
Copyright © 2007, Integrated Device Technology, Inc.
All rights reserved.
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ICSI [ INTEGRATED CIRCUIT SOLUTION INC ]
