10/100 Non-PCI Ethernet Single Chip MAC + PHY
Datasheet
0 BT
4.5 BT
3.1 V
0.5 V/ns
0.25 BT
2.25 BT
585 mV
6.0 BT
+50 mV
-50 mV
45.0 BT
585 mV sin(2
(t/1BT))
*
*
0
t
0.25 BT and
t 2.5 BT
2.25
-3.1 V
2.5 BT
4.5 BT
Figure 7.6 SOI Output Voltage Template - 10MBPS
7.7.12
Link Integrity & Autonegotiation
General
The LAN91C111 can be configured to implement either the standard link integrity algorithms or the
AutoNegotiation algorithm.
The standard link integrity algorithms are used solely to establish an active link to and from a remote
device. There are different standard link integrity algorithms for 10 and 100 Mbps modes. The
AutoNegotiation algorithm is used for two purposes: (1) To automatically configure the device for either
10/100 Mbps and Half/Full Duplex modes, and (2) to establish an active link to and from a remote
device. The standard link integrity and AutoNegotiation algorithms are described below.
AutoNegotiation is only specified for 100BASE-TX and 10BASE-T operation.
10BASE-T Link Integrity Algorithm - 10Mbps
The LAN91C111 uses the same 10BASE-T link integrity algorithm that is defined in IEEE 802.3 Clause
14. This algorithm uses normal link pulses, referred to as NLP's and transmitted during idle periods,
to determine if a device has successfully established a link with a remote device (called Link Pass
State). The transmit link pulse meets the template defined in IEEE 802.3 Clause 14 and shown in
Figure 7.7. Refer to IEEE 802.3 Clause 14 for more details if needed.
Revision 1.8 (07-13-05)
SMSC LAN91C111-REV B
DATA4S6HEET
SMSC [ SMSC CORPORATION ]
