78Q2120C Teridian Semiconductor Corp. (TDK Semiconductor), 78Q2120C Datasheet - Page 13

• Manufacturer Part Number: 78Q2120C
• Description: 10/100 Ethernet PHYS
• Manufacturer: Teridian Semiconductor Corp. (TDK Semiconductor)

78Q2120C
10/100BASE-TX Transceiver
MR1: Status Register
© 2003 TDK Semiconductor Corporation, Proprietary and Confidential
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1.1
1.0
Bit
100T2_H
EXTS
RSVD
MFPS
ANEGC
RFAULT
ANEGA
LINK
JAB
EXTD
Symbol
R
R
R
R
R
RC
R
R
RC
R
Type
0
0
0
(1)
0
0
1
0
0
0
Default Description
100BASE-T2 Half Duplex Ability: Reads ‘0’ to indicate the 78Q2120C
does not support 100Base-T2 full duplex mode.
Extended Status Information Availability: Reads ‘0’ to indicate the
78Q2120C does not support Extended Status information on MR15.
Reserved
Management Frame Preamble Suppression Support: A “0” indicates
that the 78Q2120C can read management frames with a preamble.
Auto-Negotiation Complete:
Negotiation process has been completed, and that the contents of
registers MR4,5,6 are valid.
Remote Fault: A logic one indicates that a remote fault condition has
been detected and when so, it remains set until it is cleared. This bit
can only be cleared by reading this register (MR1) via the
management interface.
Auto-Negotiation Ability:
ability to perform Auto-Negotiation. The value of this bit is determined
by the ANEGEN bit (MR0.12).
Link Status:
established. If the link status should transition from an OK status to a
NOT-OK status, this bit will become cleared and remains cleared until
it is read.
Jabber Detect: In 10Base-T mode, this bit is set during a jabber
event. After a jabber event, the bit remains set until cleared by a read
operation.
Extended Capability: Reads ’1’ to indicate the 78Q2120C provides an
extended register set (MR2 and beyond).
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A logic one indicates that a valid link has been
When set, this bit indicates the device’s
A logic one indicates that the Auto-
Rev_1.1