Avaya 03-300430 User Manual

The Maintenance/Test circuit pack (TN771D) supports packet-bus fault detection and bus 
reconfiguration for the port network where it is installed. The circuit pack also provides Analog 
Trunk testing, and data loop-back testing of DCP Mode 2 endpoints and Digital (ISDN) Trunk 
facilities via the TDM bus.
Port 1 of the Maintenance/Test board is the Analog Test port which provides the Analog Trunk 
testing function for Automatic Transmission Measurement System (ATMS). ATMS is a feature in 
which calls are made from a device called an Originating Test Line (OTL) over a specific trunk to 
a device called a Terminating Test Line (TTL). The OTL and TTL can then send tones over the 
trunk under test and determine the quality of the connection. Ports 2 and 3 are the digital ports 
which provide the digital (ISDN) trunk-testing functions. Port 4 is the packet port which provides 
the packet-bus maintenance function.
See 

on page 2539 for circuit pack-level 

errors. See also, related maintenance/test information for analog, digital, and packet-bus ports:

●

M/T-ANA (Maintenance/Test analog port)

●

M/T-DIG (Maintenance/Test digital port)

●

M/T-PKT (Maintenance/Test packet-bus port)

Every port except the analog port (Port 1) of the Maintenance/Test board is automatically 
administered when the circuit pack is inserted into the system and automatically removed when 
the circuit pack is unplugged from the system. The Analog port however, is administered using 
the station screen with the type “105TL” for an OTL or a TTL. This port remains administered 
even after the circuit pack is physically removed from the system. Care should be taken to 
remove the OTL or the TTL before unplugging the circuit pack.

M/T-BD

MIN

test board location l

Maintenance/Test circuit pack

M/T-BD

WRN

Maintenance/Test circuit pack