Total Reach Office Channel Unit Data Port Installation and Maintenance Practice
10
61292006L1-5C
Dual Function LBK Button
The TR OCU DP front panel loopback pushbutton (
LBK
) allows loopbacks to be activated
without test equipment or centralized test coordination.
• Pressing the
LBK
button once loops the TR DDS-R toward the network.
• Pressing the
LBK
button during an active loopback releases any loopbacks in the Total
Reach system.
• Pressing and holding the
LBK
button for five seconds toggles between local and alternate
(remotely-provisioned) option settings.
Loopback LED Operation
The TR OCU DP system loopback status is indicated by the front panel
NTWK LBK
and
CUST
LBK
LEDs. An active loopback occurring at the unit being viewed is indicated by a solid
loopback LED. A flashing loopback LED indicates a loopback condition at the remote unit.
When a loopback toward the network is initiated, the
NTWK LBK
LED is illuminated. A
loopback generated toward the customer illuminates the
CUST LBK
LED.
TR OCU DP Bidirectional Loopback Support
The TR OCU DP will execute a bidirectional loopback when performing an OCU DP loopback
at the TR OCU DP. This allows a standard portable DDS test set, connected to the 4-wire
customer interface of the TR DDS-R, to verify the integrity of the 4-wire loop by transmitting a
test pattern and examining the returning data for synchronization and errors. The TR OCU DP
NTWK LBK
and
CUST LBK
indicators illuminate during a TR OCU DP bidirectional loopback.
for an illustration of the bidirectional loopback. The latching and alternating
loopback sequences are defined in
and
Figure 5. OCU DP Bidirectional Loopback
TROCU DP
Bidirectional
loopback
Customer
Intra-office
