ATT System 25 Reference Manual

							FUNCTIONAL DESCRIPTION
Figure 3-21.System Software Partitioning
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							FUNCTIONAL DESCRIPTION
Memory
Administration and Feature Code Modules, which includes Station Call Processing, are
software tasks associated with memory.Each task controls the storage and movement of
data and messages between elements in the system.
l Administration
Provides for administration of station and system features. This software also
supports maintenance procedures related to error checking and diagnosing trouble.
l Feature Code Modules
Includes the software that receives and sends data to/from the Operating System, as
well as control of all voice and data features supported by the system. Station Call
Processing includes the processing of messages and data associated with voice
terminal on-hook/off-hook indications, associated port identifications, button and LED
operations, etc.The SMDR software generates SMDR records associated with a
particular call. The records are then sent to the System RAM for storage and then to
the SMDR output channel.
Call Processing
The following circuits support software tasks.
l System RAM provides for the storage of the following:
— Variables for the various software tasks
— System translations
— Error Records
— Feature Code Data
— Stack.
l Error Logger
Prioritizes and stores system errors; lights the Alarm LED on the Attendant Console
when a serious error is detected. The errors are stored in three error records in
System RAM:
— Permanent System Alarms
— Transient System Errors
— Most Recent System Errors.
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							FUNCTIONAL DESCRIPTION
l Operating System (OS)
Controls all message and data flow to/from memory, to the Arch Angel Driver
Interface, to the microprocessors on the port circuit packs, and to the RS-232 driver
interfaces. Messages destined for a particular task are queued until the associated
task can receive them. When a task has completed a particular process, the next
message is obtained from the message queue of the tasks. The OS provides an
interval timer that is used to time tasks.Processes that exceed the set interval
(about 60 seconds) are terminated by the OS.
l Arch Angel Driver Interface
Provides an interface between the OS and Network Control.
l RS-232 Driver Interface
Handles the flow of information between the CPU/MEM CP and the peripheral
equipment of the system (i.e., System Administration Terminal or Advanced
Administration PC, Digital Tape Unit, and SMDR Output Device.)
TDM Bus
Provides an electronic link between the system port circuits (including System Resources)
and between the CPU/MEM and port circuits.
Port Circuit Packs
Each port circuit pack has on-board software that provides for the sending/receiving of
Network Control messages and data.Circuit pack status messages are also sent to the
Network Control software.
Step-By-Step Call Description
The following is a description of a call originated between two multiline voice terminals.
1. A microprocessor on a station port circuit pack (port controller) continually monitors
associated port circuits for switchhook status/change and button presses.
2. When a user goes off-hook, the port controller detects the change.
3. The port controller sends an off-hook up-link message along with port identification
to the Call Processor Network Controller (CPNC) via the TDM bus.
4. The CPNC accepts the message and forwards it to the Operating System (OS) via
the Arch Angel Driver Interface.
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							FUNCTIONAL DESCRIPTION
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
The OS checks a message directory to determine which task (i.e., software module)
is to receive the message.
A function of the OS referred to as the “transformer”
determines it has a message for the Station Call Processing task and queues the
message in RAM.
The Station Call Processing task retrieves its message and interprets it as a call
origination. The task determines whether there is an idle call appearance button
(System Access button) on the called voice terminal. If so, two available time slots
are reserved for the connection.
The task sends downlink messages to the port circuit via the OS. The messages
instruct the port circuit to listen for dial tone on a specified time slot and to light the
call appearance status LED on the terminal.
When the user dials the first digit, the port circuit determines the digit dialed. It then
listens to appropriate time slots on the TDM bus for the two tones used to generate
an equivalent DTMF signal.It then removes dial tone and feeds the DTMF signal
back to the user until the user releases the button.
The port circuit sends an up-link message with each digit dialed to the OS that routes
them to the Dial Plan Manager (DPM).
The DPM collects the dialed digits and determines that the call is a station-to-station
call.
When the DPM collects enough digits to identify an extension number it stops
collecting digits.
Note:If the extension number dialed is invalid, the DPM sends a down-link
message to the port circuit instructing it to listen to time slot 07
(Reorder Tone) that is then heard by the user. Go to Step 18.
A down-link message is sent to the originating port instructing it to listen to time slot
06 (busy) or 08 (ringing), as appropriate.Go to Step 18 for Busy Tone or an
unanswered call.
Station Call Processing sends a down-link message to the station port circuit pack
associated with the called extension to turn on the ringer of the terminal, and to flash
the call appearance LED.
When the called party lifts the receiver, the associated port circuit pack controller
sends a off-hook message to the OS as before.
The Station Call Processing task, when it receives the message interprets the off-
hook message as an answer.
The task sends a down-link message to the called port circuit to turn off the ringer
and to change the flashing LED to steadily lighted.
Down-link messages are sent to the port circuits assigning talk and listen time slots
for the connection.
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							FUNCTIONAL DESCRIPTION
18. When either of the parties hangs up, the associated port circuit controller sends an
up-link message to the Station Call Processing task.
19. Station Call Processing interprets the on-hook message as the end of the call.
20. The task then sends a down-link message to the port circuit pack controllers to
disconnect the time slot connections and turn off the LEDs associated with the calls.
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							HARDWARE DESCRIPTION
System Cabinets (J58901A1 L4)
Cabinet 1 (Control and Port Circuits)
Cabinets 2 and 3 (Port Circuits)
Cabinet Address Plug4-1
4-4
4-4
4-6
Circuit Packs
Required Circuit Packs
Optional Circuit Packs
Station Port Circuit Packs
Trunk Port Circuit Packs
System Resource Circuit Packs
Circuit Pack Compatibility
Circuit Pack Features
4-7
4-8
4-9
4-9
4-11
4-12
4-13
4-13
Terminal Equipment
Voice Terminals
Single-Line Voice Terminals
500 Series
2500 Series
2526BMWG Voice Terminal
7101A Voice Terminal (MD) (PEC 3170-00M)
420 Speakerphone Voice Terminal (Not Orderable)
Single-Line Voice Terminal Connection Information
Single-Line Voice Terminal Feature Operations
Multiline Voice Terminals
7302H01D Voice Terminal (5-Button) (PEC 3160-111)
7303H01D Voice Terminal (10-Button) PEC 3161-172
7305H01D Voice Terminal (34-Button) (MD) (PEC 3162-412)
7305H02D Voice Terminal (34-Button Deluxe) (PEC 3162-417)
7305H03B Voice Terminal (BIS) (PEC 3162-BIS)
7305H04C Voice Terminal (BIS With Display) (PEC 3162-DIS)
7309H01B Voice Terminal (HFAI) (PEC 3161-161)4-14
4-14
4-16
4-16
4-16
4-19
4-20
4-21
4-22
4-22
4-23
4-24
4-26
4-28
4-30
4-32
4-34
4-36
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							7313H01A Voice Terminal (BIS-10) (PEC 3165-10B)                       4-38
7314H01A Voice Terminal (BIS-22) (PEC 3166-22B)                      4-40
7316H01A Voice Terminal (BIS-34) (PEC 3167-34B)                    4-42
7317H01A Voice Terminal (BIS-34D) (PEC 3167-DSB)                    4-44
10-Button MET Set (2991C/D05)                            4-46
10-Button MET Set With Built-In Speakerphone (2993C04)                        4-48
12-Button MET Set (7203M)                                        4-50
ATL Cordless Telephone (5-Button) (PEC 3168MLC)                                    4-52
Multiline Voice Terminal Connection Information                              4-54
Multiline Voice Terminal Feature Operations                                 4-54
Voice Terminal Adjuncts                                   4-55
Voice Terminal Adjunct Connection Information                         4-55
Voice Terminal Adjunct Power Supplies                              4-56
Attendant Consoles                                  4-56
Asynchronous Data Units (ADUs)                                    4-57
ADU Connection Information                                                  4-58
Peripheral Equipment                                                            4-60
Auxiliary Equipment                                                                4-60
Optional Power Equipment                                                                4-61
Uninterruptible Power Supply                                                          4-61
AC Power Line Surge Suppressor                                                4-61
346 Modular Bulk Power Supply                                                   4-61
Connectivity                                                        4-62
Trunk Access Equipment (TAE)                                                   4-62
Station Interconnect Panel (SIP)                                                       4-64
617A Panel                                  4-64
Adapters  4-64
Connectivity Figures                                                          4-67
Voice Terminal and Adjunct Connections                                                     4-67
Attendant Console Connections                                               4-67
Peripheral Equipment Connections                                                 4-67
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							ADU Connections                           4-68
Auxiliary Equipment Connections                                              4-68
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							Figures
Figure 4-1.
Figure 4-2.
Figure 4-3.
Figure 4-4.
Figure 4-5.
Figure 4-6.
Figure 4-7.
Figure 4-8.
Figure 4-9.
Figure 4-10.
Figure 4-11.
Figure 4-12.
Figure 4-13.
Figure 4-14.
Figure 4-15.
Figure 4-16.
Figure 4-17.
Figure 4-18.
Figure 4-19.
Figure 4-20.
Figure 4-21.
Figure 4-22.
Figure 4-23.
Figure 4-24.
Figure 4-25.
Figure 4-26.
Figure 4-27.
Figure 4-28.
Figure 4-29.
Figure 4-30.System 25 Cabinets (J58901A)—3-Cabinet System                   4-3
System Cabinet (J58901A)—Rear View                            4-4
System Circuit Pack Configurations                                   4-5
2500 Series Analog Voice Terminals                                    4-17
2526BMWG Voice Terminal                                    4-19
7101A Voice Terminal                                                   4-20
420 Speakerphone Voice Terminal                                           4-22
7302H01D Voice Terminal (5-Button)                                      4-25
7303H01D Voice Terminal (10-Button)                           4-27
7305H01D Voice Terminal (34-Button) (MD)                               4-29
7305H02D Voice Terminal (34-Button Deluxe)                             4-31
7305H03B Voice Terminal (BIS)                         4-33
7305H04C Voice Terminal (BIS With Display)                        4-35
7309H01B Voice Terminal (HFAI)                       4-37
7313H01A Voice Terminal (BIS-10)                       4-39
7314H01A Voice Terminal (BIS-22)                      4-41
7316H01A Voice Terminal (BIS-34)                        4-43
7317H01A Voice Terminal (BIS-34D)                              4-45
10-Button MET Set (2991C05)                                 4-47
10-Button MET With Built-In Speakerphone (2993C04)                       4-49
12-Button MET Set (7203M)                                4-51
ATL Cordless Telephone                                      4-53
Asynchronous Data Unit (ADU)                                           4-58
Trunk Access Equipment (TAE) Connections                                      4-63
617A Panel                                                  4-65
Typical SIP Connections                                    4-66
On-Premises Single-Line Voice Terminal Connections                     4-68
Out-of-Building Single-Line Voice Terminal Connections              4-69
Off-Premises Station Single-Line Voice Terminal Connections                 4-70
On-Premises 7300H Series Multiline Voice Terminal and ATL
Cordless Telephone Connections                                 4-71
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							Figure 4-31.Out-of-Building 7300H Series Multiline Voice Terminal Connections  -
4-72
Figure 4-32.MET Set Connections                                     4-73
Figure 4-33.
Stand-Alone Remotely Powered Multiline Voice Terminal and ATL
Cordless Telephone Connections                                  4-74
Figure 4-34.Typical ADU Connections—
Supporting Data Terminal and Single-
LineVoiceTerminal                                                 4-75
Figure 4-35.Typical ADU Connections—
Supporting Data Terminal and 7300H
Series Multiline Voice Terminal                            4-76
Figure 4-36.Typical MADU Connections                            4-77
Figure 4-37.
Z3A1/2/4 ADU Local Power Connections                       4-78
Tables
Table 4-A.Total Port Circuit Packs Per System                               4-6
Table 4-B.
System Circuit Packs                                   4-7
Table 4-C.Tone Detector Requirements                            4-12
Table 4-D.
Summary of Voice Terminals                                       4-15
Table 4-E.
2500 Series Voice Terminal Adjuncts                                 4-18
Table 4-F.
Supplemental Voice Terminal Power Supplies                                4-56
Table 4-G.Asynchronous Data Units                        4-59
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