Led Functions; Link Monitor; Rx Led - Realtek RTL8169 Manual

9.6 LED Functions

The RTL8169 supports 4 LED signals in 4 different configurable operation modes. The following sections describe the different
LED actions.

9.6.1 Link Monitor

The Link Monitor senses the link integrity or if a station is down, such as LINK10, LINK100, LINK1000, LINK10/100/1000,
LINK10/ACT, LINK100/ACT, or LINK1000/ACT. Whenever link status is established, the specific link LED pin is driven low.
Once a cable is disconnected, the link LED pin is driven high indicating that no network connection exists.

9.6.2 Rx LED

In 10/100/1000Mbps mode, blinking of the Rx LED indicates that receive activity is occurring.
2002/03/27
Power On
LED = High
Receiving
Packet?
Yes
LED = High for (100 +- 10) ms
LED = Low for (12 +- 2) ms
61
No
RTL8169
Rev.1.21