Testing | LTPH-UM-1109-01, Issue 1 |
| |
To perform the A1LB, A2LB, and the A5LB loopback test procedures:
1Send the inband Arming and NI LPBK code 11000 to the H2TU-C-231 for at least 5 seconds.
2Monitor the output of the H2TU-C-231 for the return of the pattern. Return of the pattern indicates one of the following:
•The H2TU-R has looped up (if the SMJK Loopback option is enabled).
•An external NID has looped up (if the SMJK Loopback option is disabled), and the H2TU-C and H2TU-R have been armed.
3Verify, if possible, that the H2TU-R Loopback LED is either flashing yellow at four times per second (indicating that the system is armed), or is a steady yellow (indicating that it is both armed and in SMJK loopback). The H2TU-C Status LED also flashes yellow when the system is armed.
If the Arming code is not returned after 5 seconds, the system may be armed, but there is no active loopback.
4Once armed, the H2TU-C-231 can be looped back by sending Intelligent Office Repeater (IOR) LPBK activation code 1101-0011-1101-0011 (D3D3) for at least 5 seconds. You should observe the following activation response pattern in the order presented:
a2 seconds of AIS (all ones pattern)
b2 seconds of returning data pattern
cLogic errors (including the frame bit) occurring in the returned pattern comprising:
–231 errors, if IOR LPBK (H2TU-C) was sent
–20 errors, if ILR-2 (H2TU-R) was sent
dNormal looped data
This error pattern repeats every 20 seconds as long as the IOR loopback pattern is being sent. This also applies to ILR, Time-Out Override, and Query commands.
The H2TU-C is now in logic loopback if the IOR NLOC loopback command was sent. The Time-Out Override command or a Loopdown command can override the selection made for the loopback time-out (see “Setting the Loopback Time-Out Option” on page 46). If the Time-Out Override code 1101-0101-1101-0110 (D5D6) is received after activating a loopback, then the automatic timed expiration of the loopback is inhibited. If this Time-Out Override is sent, then the only way to loop the H2TU-C-231 down is to do one of the following:
•Issue the Intelligent Repeater (IR) loopdown (LPDN) code 1001-0011-1001-0011 (9393).
•Issue the NI LPDN and Disarm inband code 11100 or the ESF-DL code (FF24).
The Time-Out Override function is only valid for the current active loopback. The automatic time-out timer is restored during subsequent loopback sessions.
5Once the test is complete, do one of the following:
•If the system is to loop down but remain Armed, send the IR LPDN code.
•If all the equipment is to be looped down, disarmed, and returned to normal operation, send the disarm inband code 11100 or the ESF-DL code (FF24).
