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Multiserver 5000
244
LL RT SI RD TD
Figure E-5. CSU/DSU Module Indicator Positions.
LED
Indicator
Indicator
Definition
Off
Flashing
On
LL
Local Loopback
Normal operation
Local Loopback Test
---
is active
RT
Remote Terminal
Normal operation
Digital Loopback or Remote
---
Terminal Loopback Test is
active
SI
Status Indicator
Power is off or
CSU/DSU is receiving
Power is on and
module is defective
out-of-service signals from
CSU/DSU is
code, or out-of-frame DDS
synchronized with
code, or no DDS signal
the network
is being passed
RD
Received Data
No data is being
CSU/DSU module is
CSU/DSU module
received by the
receiving error during
is receiving data
CSU/DSU module
Test Pattern Test
TD
Transmitted Data
Not data is being
Data is being
Data is being
Table E-5. CSU/DSU Module Indicators