Section 150-388-124
Revision 01
Page 21
TABLE 4. HLU-388 A2LB TEST PROCEDURES (CONTINUED)
Step
Action
5
Using the following codes, a network tester can activate loopbacks NLOC or NREM or SMJK
(if ENAbled, see Figure 6). A customer tester can activate loopbacks CLOC or CREM.
ADDRESSABLE 2 (A2LB) REPEATER LOOPBACK COMMANDS
ARMING or NI LPBK (in-band)
Arming code
11000 11000 ...
ARMING or NI LPBK (ESF data link)
Arming code
1111 1111 0100 1000 (FF48)*
IR LPDN or DISARM (in-band)
Disarming code
11100 11100 ...
DISARM (ESF data link)
Disarming code
1111 1111 0010 0100 (FF24)
IOR LPBK
(NLOC and CREM 231 errors)
HLU Loop-up
1101 0011 1101 0011 (D3D3)
ILR-2 LPBK
(NREM and CLOC 20-bit errors)
HRU Loop-up
1100 0111 0100 0010 (C742)
IR LPDN
Loop-down (HLU
or HRU)
1001 0011 1001 0011 (9393)
IR QUERY LPBK
Query Loopback
1101 0101 1101 0101 (D5D5)
IR ALTERNATE QUERY LPBK
Alternate Query
Loopback
1101 0101 1110 1010 (D5EA)
TIME-OUT OVERRIDE
Loopback Time-
out Override
1101 0101 1101 0110 (D5D6)
FAR END NI ACTIVATE
Unblock AIS and
pass 2 in 5
1100 0101 0101 0100 (C554)
IOR POWER-DOWN (HLU)
Removes HDSL
line power
0110 0111 0110 0111 (6767)
Note
:
The left-most bit arrives first in all sequences. The detection algorithm functions reliably with a
random 10
-3
Bit Error Ratio (BER) on the facility. The IOR Power-down code must remain
present for the duration of the power-down mode. When this code is removed, the HiGain
system returns to its normal unlooped and unarmed state.
6
After testing is complete, send the universal Intelligent Repeater Loop-down (IR LPDN) code if the
system is to loop down but remain Armed. Send the disarm code 11100 if all the equipment is to be
looped down, disarmed, and returned to normal operation. Note that the Armed mode has an automatic
time-out of 120 minutes.
7
All of the above loopbacks can also be initiated from the front panel of the HLU-388, List 2D with the
Mode and SEL push buttons (see Section B Paragraph 14.09). *This is the HEX number for the 16 bit
group.