Avaya S8700 Maintenance Manual page 1434

Maintenance-Object Repair Procedures
DS1 Facilities Connectivity Test (#790)
This test is destructive.
The DS1 facilities connectivity test will check the correct connectivity of the DS1
facilities at opposite ends of the DS1 CONV complex. Every part of this test is
executed under firmware control and the result is sent back to the maintenance
software.
For TN574 DS1 Converter circuit packs, this test is executed by sending digital
data through each time slot of every DS1 facility channel. Two different test
patterns are used, these are hexadecimal values 55 and AA.
For TN1654 DS1 Converter circuit packs, this test has been enhanced to provide
error codes that point to the exact fault. Rather than simply reporting a failure of
the connectivity test, the TN1654 test specifically identifies the two DS1 facilities
that are cross-connected at the near and far ends of the DS1 converter complex.
In addition, a fault code will indicate the condition of not being able to loop-up the
far end, as required to run the test, due to the packet DS1 facility being down.
The TN1654 connectivity test sends digital data through only one time slot.
Instead of looping back the facility to itself, the TN1654 version of the test
loops-up the other three facilities. If the test pattern comes back, the firmware
fails the test due to an incorrect connection between DS1 facilities. It should be
noted that this test will pass and give no indication of problems if the non-packet
facilities are down.
For a duplex-, or high-reliability system (no PNC duplication), this test can only be
executed at the endpoint that is closer to the media server relative to the neighbor
DS1 CONV circuit pack because of its impacts on the system control links. In
addition, for TN574 DS1 CONV boards, the completion of the test will be delayed
in this configuration to wait for the recovery of the system control links. For a
critical-reliability system (PNC duplication), test can be executed at any DS1
CONV circuit pack.
8-712 Issue 1 May 2002 555-233-143