In Full - Duplex Mode . W; Duplex Mode , The Led; Hen The Port Is Operating In Half - Indicator Is Not Lit - D-Link DES-1200M User Manual

ACT This LED indicator blinks green when the port is
transmitting or receiving packets. When the device is not
attached, the LED indicator is not lit.
LK100 The LED indicator is green when the Port is linking
with 100Mbps mode. When the port is operating in 10Mbps
mode or not connected, the LED indicator is not lit.
FD The LED indicator is yellow when the port is operating
in Full-duplex mode. When the port is operating in Half-
duplex mode, the LED indicator is not lit.
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