Intel ESM-2740 用户手册

 

40 ESM-2740/2743 User’s Manual

 

 

TXD#, TXD 

Ethernet Transmit Differential Pair. These pins transmit the serial bit stream on the 
Unshielded Twisted Pair (UTP) cable. The current-driven differential driver can be 
two-level (10BASE-T) or three-level (100BASE-TX) signals depending on the 
mode of operation. These signals interface to the Ethernet cable through an 
isolation transformer. 

RXD#, RXD 

Ethernet Receive Differential Pair. These pins receive the serial bit stream from the 
isolation transformer. The bit stream can be transmitted in either two-level 
(10BASE-T) or three-level (100BASE-TX) signals depending on the mode of 
operation. These signals interface to the Ethernet cable through an isolation 
transformer. 

ACTLED 

The Activity LED pin indicates either transmitted or received data activity on the 
Ethernet port. 
This pin is asserted low when activity is detected. It can sink 5mA to ground 
through an external LED and a limiting resistor to a 3.3V source. 

LILED 

The Link Integrity LED pin indicates link integrity. This pin is asserted low when the 
link is valid. It can sink 5mA to ground through an external LED and a limiting 
resistor to a 3.3V source. 

SPEEDLED 

The Speed LED pin indicates high speed operation. This LED is not supported by 
ESM-2740/2743. 
This pin is asserted low when a 100Mbps link is detected, and is not asserted for a 
10Mbps link. It can sink 5mA to ground through an external LED and a limiting 
resistor to a 3.3V source.