Issue 1, Section 150-231-164
Revision 04
Page 41
TABLE 15. HLU-231 A2LB TEST PROCEDURES (CONTINUED)
Step
Action
5
Using the following codes, a network tester can activate loopbacks NLOC or NREM or SMJK (if
enabled) shown in Figure 14. 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(F)*1111(F)0100(4)1000(8)
IR LPDN or DISARM (in-band)
Disarming code
11100 11100 ...
DISARM (ESF Data Link)
Disarming code
1111(F)1111(F)0010(2)0100(4)
IOR LPBK (NLOC & CREM 231 errors)
HLU Loop up
1101(D)0011(3)1101(D)0011(3)
ILR-1 LPBK
(NDU1 & CDU1 10 bit errors)
DOUBLER-1
Loop up
1100(C)0111(7)0100(4)0001(1)
ILR-20 LPBK
(NDU2 & CDU2 200 bit errors)
DOUBLER-2
Loop up
1100(C)0111(7)0101(5)0100(4)
ILR-2 LPBK
(NREM & CLOC 20 bit errors)
HRU Loop up
1100(C)0111(7)0100(4)0010(2)
IR LPDN
Loop down
(HLU or HRU)
1001(9)0011(3)1001(9)0011(3)
IR QUERY LPBK
Query loopback
1101(D)0101(5)1101(D)0101(5)
IR ALTERNATE QUERY LPBK
Alternate Query
loopback
1101(D)0101(5)1110(E)1010(A)
TIME-OUT OVERRIDE
Loopback Time-
out Override
1101(D)0101(5)1101(D)0110(6)
FAR END NI ACTIVATE
Unblock AIS &
pass 2 in 5
1101(C)0101(5)0101(5)0100(4)
IOR POWER DOWN (HLU)
Removes HDSL
line power
0110(6)0111(7)0110(6)0111(7)
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. This is the HEX number for the 4-bit group.
6
After testing is complete, send the universal IR loop-down [IR (Intelligent Repeater) 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-231 List 6D with the
MODE and SEL push-buttons (Section C Paragraph 3.10).
