61200.130L1-1 FSU User Manual 15
Chapter 3. Operation
LED Descriptions
The FSU has seven LED indicators: TD1, RD1, TD2, RD2, TDN,
RDN, and ALM/TST. These LEDs are identified as follows:
TD1: Transmit Data (DTE 1)
This LED is active when the FSU DTE 1 port is transmitting data.
RD1: Receive Data (DTE 1)
This LED is active when the FSU DTE 1 port is receiving data.
TD2: Transmit Data (DTE 2)
This LED is active when the FSU DTE 2 port is transmitting data.
RD2: Receive Data (DTE 2)
This LED is active when the FSU DTE 2 port is receiving data.
TDN: Transmit Data (Network)
This LED is active when the FSU Network port is transmitting
data.
RDN: Receive Data (Network)
This LED is active when the FSU Network port is receiving data.
ALM/TST: Alarm/Test
This LED is active when an alarm condition exists or when the
unit is in test mode. Alarm conditions include:
DDS Alarm Conditions
• Open loop on network
• No frame synchronization
Frame Relay Alarm Condition
• Network frame relay signaling state is down.
External DSU/CSU Alarm Condition
• DSR on an external DSU/CSU is false.