DEFINITY ECS Release 8.2 Maintenance for R8.2csi
555-233-119 Issue 1
April 2000
Maintenance Objects
3-600DS1-BD (DS1 Interface Circuit Pack)
3
CSU Repeater Loopback Test (#1211)
This test is destructive.
The CSU Repeater Loopback (RLB) Test causes a loopback at the far -edge of
the local 120A CSU Module or T1 Sync Splitter, and test s the connection from the
TN767E DS1 board to and including the CSU Module/T1 Sync Splitter circuitry.
This test will only be performed if the 120A CSU Module/T1 Sync Splitter is
present, administered, and c onnected to a 1.544 Mbp s TN767E DS1 circuit pack
on the back of the port c arrier.
The test is destructive and c an only be initiated b y a system technician
demanded test ds1-loop UUCSS ds1/csu-loopback-tests c ommand.
All trunks or ports on the DS1 Interface c ircuit pack must b e busied out via the
system technician busyout board command before running the RLB Test.
When the RLB Test is initiated, maintenance software sends an approp riate
message to the TN767E DS1 Interface circuit pac k to start the test. The board will
set up the RLB loopback, t ransmit a test pattern, and verify that th e pattern is
received unaltered through the loop back. If the transmitted and received patter n
is different, the test fails.
In addition, the DS1 circuit p ack hardware app lies a DC current while the test is
running in order to detec t any broken wires which may not be detected by the
loopback pattern.
When the test is complete, all trunks or por ts on the TN767E DS1 Interface circuit
pack are restored to the in-servic e state after the release board command is
entered.