Cisco CISCO2650 - 2650 Router Hardware Installation Manual page 202

HSSI Network Module LEDs
Table 13-1 HSSI Network Module LEDs
LED
LB/C
(Loopback/Connect)
RC (Receive Clock)
RD (Receive Data)
TC (Transmit Clock)
TD (Transmit Data)
Cisco Network Modules Hardware Installation Guide
13-4
Meaning
Green indicates normal operation. The module is connected to the external
DSU, and the signals TA (DTE available) and CA (DCE available) are active.
Yellow indicates that the module is in loopback mode.
If this LED is off, the port is neither connected to the DSU nor in loopback
mode.
Module has detected a receive clock signal. During normal operation, this
signal is received from the external DSU. During loopback, it is generated
internally.
Module has detected a receive clock signal. During normal operation, this
signal is received from the external DSU. During loopback, it is generated
internally.
Module is transmitting a clock signal to the external DSU. During normal
operation, this signal is derived from the DSU's RT signal. During loopback,
it is generated internally.
Module has been detected by and can send packets to the external DSU.
Chapter 13 Connecting HSSI Network Modules
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