ADC H2TU-C-388 A3LB and A4LB Test Procedures

152-388-100-02, Issue 2 Testing

A3LB and A4LB Test Procedures

The H2TU-C-388 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 H2TU-C-388 to enter the NLOC state. The Loopback Time-out setting (see “Setting the Loopback Time-out Option” on page 42) 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 way to loop the H2TU-C-388 down is to issue one of the three loopdown commands listed in Table 17. The automatic time-out mode is restored during subsequent loopback sessions.

Table 17 summarizes the codes required to execute Addressable 3 (A3LB) and Addressable 4 (A4LB) repeater loopback commands. All code sequences must be present for at least 5 seconds.

Table 17. Addressable Repeater Loopback Commands (A3LB and A4LB)

Name	Description	Binary Code (a) (Hexadecimal Equivalent)
NLOC	H2TU-C-388 loopup from NI	1111-1111-0001-1110 (FF1E)
CREM	H2TU-C-388 loopup from CI	0011-1111-0001-1110 (3F1E)
NREM	H2TU-R loopup from NI	1111-1111-0000-0010 (FF02)
CLOC	H2TU-R loopup from CI	0011-1111-0000-0010 (3F02)
SMJK	H2TU-R loopup from NI	11000-11000-11000 ...
SMJK	H2TU-R loopup from NI (b)	100000 100000 100000 ...
SMJK	H2TU-R loopup from NI (ESF-DL)	1111-1111-0100-1000 (FF48)
Loopdown	H2TU-C and H2TU-R loopdown from NI OR CI	11100-11100-11100 ...
Loopdown	H2TU-C and H2TU-R loopdown from NI OR CI	100-100-100 ...
Loopdown	H2TU-C and H2TU-R loopdown from NI OR CI (ESF-DL)	1111-1111-0010-0100 (FF24)

(a)The leftmost bit arrives first in all sequences. The detection algorithm functions reliably with a random 10-3BER on the facility. The entire arming and loopback sequence can also be initiated at the remote H2TU-R location.

(b)Not supported by A4LB.

H2TU-C-388 List 1 June 6, 2000 47