1893CFLFT IDT, 1893CFLFT Datasheet - Page 53

• Manufacturer Part Number: 1893CFLFT
• Description: Ethernet ICs 3.3V 10/100 BASE TX INTEGRATED PHYCEIVER
• Manufacturer: IDT

Specifications of 1893CFLFT

• Rohs: yes
• Part # Aliases: ICS1893CFLFT

7.3.9 Remote Fault (bit 1.4)
7.3.10 Auto-Negotiation Ability (bit 1.3)
7.3.11 Link Status (bit 1.2)
ICS1893CK-40, Rev. C, 06/02/09
An STA reads bit 1.4 to determine if a Remote Fault exists. The ICS1893CK-40 sets bit 1.4 based on the
Remote Fault bit received from its remote link partner. The ICS1893CK-40 receives the Remote Fault bit as
part of the Link Code Word exchanged during the auto-negotiation process. If the ICS1893CK-40 receives
a Link Code Word from its remote link partner and the Remote Fault bit is set to:
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Bit 1.4 is a latching high status bit. (For more information on latching high and latching low bits, see
7.1.4.1, “Latching High Bits”
Note:
The STA reads bit 1.3 to determine if the ICS1893CK-40 can support the auto-negotiation process. If the
ICS1893CK-40:
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The purpose of this bit 1.2 (which is also accessible through the QuickPoll Detailed Status Register, bit
17.0) is to determine if an established link is dropped, even momentarily. To indicate a link that is:
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This bit is a latching low (LL) bit that the Link Monitor function controls. (For more information on latching
high and latching low bits, see
Bits”.) The Link Monitor function continually observes the data received by either its 10Base-T or
100Base-TX Twisted-Pair Receivers to determine the link status and stores the results in the Link Status
bit.
The criterion the Link Monitor uses to determine if a link is valid or invalid depends on the following:
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For more information on the Link Monitor Function (relative to the Link Status bit), see
“10Base-T Operation: Link
Zero, then the ICS1893CK-40 sets bit 1.4 to logic zero.
One, then the ICS1893CK-40 sets bit 1.4 to logic one. In this case, the remote link partner is reporting
the detection of a fault, which typically occurs when the remote link partner is having a problem with its
receive channel.
Cannot support the auto-negotiation process, it clears bit 1.3 to logic zero.
Can support the auto-negotiation process, it sets bit 1.3 to logic one. (For the ICS1893CK-40, the default
value of bit 1.3 is logic one.)
Valid, the ICS1893CK-40 sets bit 1.2 to logic one.
Invalid, the ICS1893CK-40 clears bit 1.2 to logic zero.
Type of link
Present link state (valid or invalid)
Presence of any link errors
Auto-negotiation process
The ICS1893CK-40 has two versions of the Remote Fault bit.
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The operation of both bit 1.4/17.1 and bit 5.13 are in compliance with the IEEE Std 802.3u.
ICS1893CK-40 Data Sheet Rev. C - Release
One version of the Remote Fault bit is a latching high version. An STA can access this version
through either Management Register 1 (bit 1.4) or 17 (bit 17.1). This bit 1.4/17.1 is cleared when
an STA reads either of these registers. (Bit 1.4 is identical to bit 17.1 in that they are the same
internal bit.)
Another version of the Remote Fault bit is updated whenever the ICS1893CK-40 receives a new
Link Control Word. An STA can access this version through Management Register 5 (bit 5.13),
which like bits 1.4/17.1, also reports the status of the Remote Fault bit received from the remote
link partner. However, bit 5.13 is not a latching high bit.
Monitor”.
and
Copyright © 2009, Integrated Device Technology, Inc.
Section 7.1.4.1, “Latching High Bits”
Section 7.1.4.2, “Latching Low
All rights reserved.
53
Bits”.)
and
Chapter 7 Management Register Set
Section 7.1.4.2, “Latching Low
Section 6.5.5,
June 2009
Section