DEFINITY Enterprise Communications Server Release 5
Maintenance and Test for R5vs/si
555-230-123 Issue 1
April 1997
Maintenance Object Repair Procedures
Page10-513DIOD-TRK (DIOD Trunk) [G1.2SE]
10
DIOD-TRK (DIOD Trunk) [G1.2SE]
Direct Inward and Outward Dial (TN429 DIOD) trunks are 2-wire analog lines to
the CO which support the following services:
■both incoming and outgoing CO calls
■DID trunk
■DID Trunk and 1-way Outgoing DIOD
The DIOD Trunk circuit pack provides eight ports for loop-start CO. The circuit
pack is an interface between the 2-wire analog line from the CO and the system’s
(4-wire) TDM Bus.

LOOP START OPERATION

Idle State - Tip = ground, Ring = CO Battery
A. Outgoing Call
1. PBX Off-Hook (Seize Message): Closes the Tip-Ring Loop
a. CO Response: DC loop current + Dial tone
2. PBX On-Hook (Drop Message): Open Tip-Ring loop, no loop current
a. CO Response: CO g o e s to idle state (see No te)

B. Incoming Call

1. CO Applies Ringing Voltage
a. PBX Response: Detect ringing current
1. Where P is the port network number (1 for PPN, 2 for EPN, and 3 for the second EPN);
C is the carrier designation (for example, A, B, C, D, or E); and SS is the address of the
slot in the carrier where the circuit pack is located (for example, 01, 02, ...et c.).
2. A MAJOR alarm on a trunk indicates that alarms on these trunks are not downgraded
by the set options command and that at least 75 percent of the trunks in this trunk
group are alarmed.
MO Name As
It Appears in
Alarm Log Alarm
Level
Initial System
Technician
Command to Run1Full Name of MO
DIOD-TRK MAJOR2test port PCSSpp l DIOD Trunk
DIOD-TRK MINOR test port PCSSpp l DIOD Trunk
DIOD-TRK WARNING test port PCSSpp l DIOD Trunk