ADTRAN Total Reach TROCU DP, Установка и эксплуатация

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Total Reach Office Channel Unit Data Port Installation and Maintenance Practice
12 61292006L1-5C
Remote End Initiated LBK Tests
The TR OCU DP supports loopbacks generated from the TR DDS-R, which allow testing to be
performed without coordination with the central office (CO) or test center. Loopbacks initiated
by the TR DDS-R front panel
LBK
pushbutton aid in system turnup testing or troubleshooting
from the remote end. The TR OCU DP responds to a loopback command initiated at the TR
DDS-R as follows:
• Pressing the TR DDS-R
LBK
pushbutton once initiates a loopback at the TR OCU DP toward
the customer. Refer to Figure 6 . This allows data to be sent from the remote end to test the
local loop and the TR DDS-R. This loopback is indicated by a flashing
CUST
LED on the TR
DDS-R and a solid
CUST
LED on the TR OCU DP.
• Pressing the
LBK
pushbutton a second time initiates a loopback at the TR DDS-R toward
the 4-wire DDS (CPE) interface. Refer to Figure 7 . A solid
CUST LBK
LED on the TR DDS-R
indicates a loopback at the TR DDS-R toward the customer equipment.
• Pressing the TR DDS-R
LBK
pushbutton a third time disables all current latching
loopbacks.
If errors exist, the loopbacks can help determine the source, either the local loop or the TR
DDS-R. During a remote end initiated loopback, the Total Reach system transmits ASC (9Eh)
toward the network, indicating an out-of-service condition generated by the remote end, as
shown in
Figure 6 and Figure 7 .
All Total Reach system latching loopbacks, whether initiated by a
LBK
pushbutton, CO, or
from a remote Test Center, can be released by sending 35 DDS loop down TIP bytes
<X0111010> (where X is a “don’t care” bit). All existing latching loopbacks can also be
disabled by pressing the
LBK
pushbutton on the CO or remote unit.
Figure 6. TR DDS-R Remote End Initiated Loopback, Local Loop
Figure 7. TR DDS-R Remote End Initiated Loopback, Customer Loop
4-Wire
CPE Interface
TR DDS-R
Push once for TR OCU DP
Loopback
Local Loop
ASC 9Eh
TR OCU
DP
Loopback
Pushbutton
Test
Set
4-Wire
CPE Interface
TR
DDS-R
Push twice for TR DDS-R
Loopback
Local Loop
ASC 9Eh
TR OCU
DP
Loopback
Pushbutton
Test
Set
ASC 9Eh