ADC HiGain HLU-200 User Manual page 37

150-200-114-03, Issue 03
Step
1 Send into the HLU-200 List 1D the inband ARMING and NI LPBK code 11000 for at least five
seconds.
2 Monitor the output of the HLU-200 List 1D for the return of the pattern. Return of pattern indicates
that either the HRU-412 has looped-up (if the SMARTJACK LOOPBACK option is ENABLED) or
that an external NI has looped up (if the SMARTJACK LOOPBACK option is DISABLED) and that
the HLU-200 List 1D and HRU-412 units have been ARMED. Verify, if possible, that the
LOOPBACK LED of the HRU-412 is flashing, indicating that the HRU-412 is armed or that it lights
steadily, indicating that it is both armed and in loopback.
3 Once armed the HLU-200 List 1D can be looped back (NLOC in Figure 7 for non-doubler loopback
configuration) by sending IOR LPBK activation code 1101 0011 1101 0011(D3D3) for at least five
seconds. The tester observes the following activation response:
•
Two seconds of AIS (all ones), followed by:
•
Five seconds of returning data pattern, followed by:
•
231 logic errors (including the frame bit) occur in the returned pattern [10 errors if ILR-1
(Doubler 1) was sent, 200 errors if ILR-20 (Doubler 2) was sent, and 20 errors if ILR-2
(HRU) was sent], followed by:
•
Normal looped data. Note that this error pattern will repeat every 20 seconds as long as the
IOR loopback pattern is being sent. This same 20 second repeat scenario also applies to ILR,
Time-Out Override and Query commands.
The HiGain Line Unit is now in Logic Loopback (NLOC in Figure 7 for non-doubler loopback
configuration.) The Loopback Time-out option, which is user settable to NONE, 20, 60 or 120
minutes, determines the duration of this loopback unless it is overridden by the TIME-OUT
OVERRIDE command or a loop down command is sent. If the Time-out Override code 1101 0101
1101 0110 (D5D6) is received, the activation sequence described in 3 above is repeated and the
automatic timed expiration of the loopback is inhibited. If this Time-out Override is sent, then the only
way to loop the HLU-200 List 1D down is to issue the IR (Intelligent Repeater) LPDN (loop-down)
code 1001 0011 1001 0011 (9393) or to issue the NI LPDN and Disarm code 11100. The automatic
time-out timer is restored during subsequent loopback sessions.
4 Upon completion, the tester sends IOR LPDN code 1001 0011 1001 0011 (9393) to loop-down the
HLU-200 List 1D. The unit remains armed however, as indicated by the flashing of the HRU-412
LOOPBACK LED.
HLU-200 List 1D
Table 13. HLU-200 A2LB Test Procedures
Action
November 22, 1996
Continued
35