Filter
Top Products
152-402-145-02, Issue 2 Loopback Operation
H2TU-R-402 June 16, 2000 29
4 Once armed, the H2TU-R-402 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:
a 2 seconds of AIS (all ones pattern)
b 2 seconds of returning data pattern
c Logic errors (including the frame bit) occurring in the returned pattern comprising:
– 231 errors, if IOR LPBK (H2TU-R-402) was sent
– 20 errors, if ILR-2 (H2TU-R) was sent
d Normal 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. 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-R-402 down is to do one of the following:
• Issue the IR loopdown (LPDN) code 1001-0011-1001-0011 (9393)
• Issue the NI LPDN and Disarm inband code 11100 or the ESF-DL code (FF24).
5 Once 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).
The Time-out Override function is only valid for the current active loopback. The automatic
time-out timer is restored during subsequent loopback sessions.
The Armed mode has an automatic time-out of 120 minutes, but this timer is reset to 120 for any
of the following events:
• Loopback terminates (manually or time-out)
• Query
• Alternate query
• Far End activate
• Another ARM command
This timer is inhibited while any of the valid command codes are being sent. Once the codes
are removed, the timer restarts at 120.