LAN83C183 Datasheet, PDF (33/113 Pages) SMSC Corporation – FAST ETHERNET PHYSICAL LAYER DEVICE

shown in Figure 1.6. A timing diagram contrasting NLPs and FLPs is shown in
Figure 1.7.
Figure 1.7 NLP vs FLP Link Pulse
TPO±
TPO±
Normal Link Pulse (NLP)
Fast Link Pulse (FLP)
D0 D1 D2 D3 D14 D15
Clock Clock Clock Clock Clock Clock Clock
Data Data Data Data Data Data
Any of the following events initiates the AutoNegotiation algorithm:
• Power up
• Device reset
• The AutoNegotiation Enable (ANEG_EN) bit in the MI serial port Control register
for that port is cleared, then set
• The AutoNegotiation Reset (ANEG_RST) bit in the MI serial port Control register
is set
• The channel enters the Link Fail state
Once a negotiation has been initiated, the device first determines if the remote device
has AutoNegotiation capability. If the remote device is not AutoNegotiation capable
and is just transmitting either 10BASE-T or 100BASE-TX signals, the device senses
it and places itself in the same mode as the remote device.
If the device detects FLPs from the remote device, the remote device is determined
to have AutoNegotiation capability, and the device then uses the contents of the MI
serial port AutoNegotiation Advertisement register for that port to advertise its
capabilities to the remote device.
The remote device does the same, and the capabilities read back from the remote
device are stored in the MI serial port AutoNegotiation Remote End Capability
register. The LAN83C183 negotiation algorithm then matches its capabilities to the
remote device’s capabilities and determines the device configuration according to the
priority resolution algorithm defined in IEEE 802.3 Clause 28.
When the negotiation process is completed, the LAN83C183 then configures itself
for either 10 or 100 Mbits/s mode and either Full- or Half-Duplex modes (depending
on the outcome of the negotiation process), and it switches to either the 100BASE-
TX or 10BASE-T link integrity algorithms (depending on which mode was enabled
through AutoNegotiation). Refer to IEEE 802.3 Clause 28 for more details.
1.2.11.4 AUTONEGOTIATION OUTCOME INDICATION
The outcome or result of the AutoNegotiation process is stored in the 10/100 Speed
Detect (SPD_DET) and Duplex Detect (DPLX_DET) bits in the MI serial port Status
Output register.
SMSC DS – LAN83C183
33
Rev. 12/14/2000