A3Lb Test Procedures - ADC H4TU-C-231-L5A User Manual

LTPH-UM-1253-01

A3LB Test Procedures

The H4TU-C can be looped back by sending the Addressable Office Repeater (AOR) LPBK activation code
1111-1111-0001-1110 (FF1E) for at least 5 seconds. This causes the H4TU-C to enter the NLOC state. The
Loopback Time-Out setting determines the duration of this loopback unless it is overridden by the reception of a
second identical 16-bit loopup command before the timer expires. When this time-out override state exists, the
only method to loop the H4TU-C down is to issue one of the three loopdown commands listed in
automatic time-out mode is restored during subsequent loopback sessions.
Table 18 summarizes the codes required to execute Addressable 3 (A3LB) repeater loopback commands. All code
sequences must be present for at least 5 seconds.
Name Binary Code
NLOC 1111-1111-0001-1110 (FF1E)
CREM 0011-1111-0001-1110 (3F1E)
NREM 1111-1111-0000-0010 (FF02)
NDU1 1111-1111-0000-0100 (FF04)
CDU1 0011-1111-0000-0100 (3F04)
NDU2 1111-1111-0000-0110 (FF06)
CDU2 0011-1111-0000-0110 (3F06)
CLOC 0011-1111-0000-0010 (3F02)
(b)
SMJK 11000-11000-11000 ...
(b)
SMJK 100000 100000 100000 ...
(b)
SMJK 1111-1111-0100-1000 (FF48)
Loopdown 11100-11100-11100 ...
Loopdown 100-100-100 ...
Loopdown 1111-1111-0010-0100 (FF24)
(a) The leftmost bit arrives first in all sequences. The detection algorithm functions reliably with a random 10
(BER) on the facility. The entire arming and loopback sequence can also be initiated at the remote H4TU-R location.
(b) This command is valid only when the SMJK loopback option (LBPK) is enabled.
H4TU-C-231 List 5AA
Table 18. A3LB Addressable Repeater Loopback Commands
(a)
(Hexadecimal Equivalent)
October 15, 2003
Description
H4TU-C loopup from NI.
H4TU-C loopup from CI.
H4TU-R loopup from NI.
Signal is looped back to the network at H4D1.
DS1 signal from customer is looped back to the customer at H4D1.
Signal is looped back to the network at H4D2.
DS1 signal from customer is looped back tot he customer at H4D2.
H4TU-R loopup from CI.
H4TU-R loopup from NI.
H4TU-R loopup from NI.
H4TU-R loopup from NI (ESF-DL).
H4TU-C and H4TU-R loopdown from NI OR CI.
H4TU-C and H4TU-R loopdown from NI OR CI.
H4TU-C and H4TU-R loopdown from NI OR CI (ESF-DL).
Testing
Table 18. The
-3
Bit Error Ratio
47