dp83840a National Semiconductor Corporation, dp83840a Datasheet - Page 49

• Manufacturer Part Number: dp83840a
• Description: 10/100 Mb/s Ethernet Physical Layer
• Manufacturer: National Semiconductor Corporation

Version A
4.0 Registers
4.8 AUTO-NEGOTIATION EXPANSION REGISTER (ANER)
Address 06h
4.9 DISCONNECT COUNTER REGISTER (DCR)
Address 12h
4.10 FALSE CARRIER SENSE COUNTER REGISTER (FCSCR)
Address 13h
15:5
15:0
15:0
Bit
Bit
Bit
4
3
2
1
0
FCSCNT[15:0]
LP_NP_ABLE
LP_AN_ABLE
DCNT[15:0]
PAGE_RX
NP_ABLE
Bit Name
Bit Name
Bit Name
Reserved
MLF
(Continued)
<0000h>, RW/SC DISCONNECT COUNTER: This 16-bit counter increments for each
<0000h>, RW/SC FALSE CARRIER EVENT COUNTER: This 16-bit counter increments
0, RO/P
0, RO/L
Default
Default
Default
0, RO
0, RO
0, RO
0, RO
RESERVED: Always 0.
MULTIPLE LINK FAULT:
1 = Multiple Link Fault--indicates that it was not possible to resolve the
0 = No Multiple Link Fault
LINK PARTNER NEXT PAGE ABLE: Status indicating if the Link
Partner supports Next Page negotiation. A one indicates that the Link
Partner supports Next Page.
NEXT PAGE ABLE: Indicates if this node is able to send additional
“Next Pages”. The DP83840A is not Next Page Able, so this bit is always
zero.
LINK CODE WORD PAGE RECEIVED: This bit is set when a new Link
Code Word Page has been received. This bit is automatically cleared
when the Auto-Negotiation Link Partner Ability Register (ANLPAR
register 05h) is read by management.
LINK PARTNER AUTO-NEGOTIATION ABLE: A one in this bit
indicates that the Link Partner supports Auto-Negotiation.
disconnect event. Each time this DP83840A and its Link Partner are
disconnected from each other, the counter increments. This counter
automatically rolls over to 0000h.
for each false carrier event, that is, when carrier sense is asserted
without J/K symbol detection. This counter freezes when full (at FFFFh).
This counter represents the total number of false carrier events since
the last management read. The Carrier Integrity Monitor uses its own
counter to qualify whether the link is unstable.
connection because the 10BASE-T Link Integrity Test function and/
or the 100BASE-X Link Integrity Monitor indicated a valid link yet
both or neither of these functions maintained a valid link according to
Auto-Negotiation specification. This bit generally indicates that the
receive channel is improperly functioning or improperly connected.
49
National Semiconductor
Description
Description
Description