
Overview
Page 53 of 906
Circuit Card
Description and Installation
Incoming Calls
Incoming calls to terminal equipment that is connected to the lineside T1 card
can originate either from stations that are local (served by the PBX), or
remote (served through the public switched telephone network). To provide
the ringing signal to the terminal equipment the lineside T1 card simulates the
90V ring signal on the ring lead by alternating the transmit B bit between 0
and 1 (0 during ring on, 1 during ring off), and ground on the tip lead by
setting the transmit A bit to 0. When an incoming call is answered (by the
terminal equipment going off-hook), the terminal equipment simulates
tripping the ringing and shutting off ringing by causing the lineside T1’s
receive A bit to change from 0 to 1. The lineside T1 card responds to this
message by simulating loop closure by holding the transmit B bit constant
at 1.
Outgoing Calls
During outgoing calls from the terminal equipment, a channel is seized when
the terminal equipment goes off-hook, simulating a ground to the ring lead
toward the lineside T1 card by causing the lineside T1’s receive B bit to
change from 1 to 0. In turn, the lineside T1 card simulates grounding its tip
lead by changing the transmit A bit to 0. The terminal equipment responds to
this message by removing the ring ground (lineside T1’s receive B bit is
changed to 1) and simulating open loop at the terminal equipment (lineside
T1’s receive A bit is changed to 0).
Call disconnect from far end (PSTN, private network or local
station
While a call is in process, the far end might disconnect the call. If the lineside
T1 port has been configured with the Supervised Analog Line (SAL) feature,
the lineside T1 will respond to the distant end disconnect message by opening
tip ground. This causes the lineside T1 card to change the transmit A bit to 1.
When the terminal equipment sees the transmit A bit go to 1, it responds by
simulating open loop causing the lineside T1’s receive A bit to change to 0.
The call is terminated and the interface is once again in the idle condition.
For the lineside T1 card to support distant end disconnect in ground start
mode, the following configuration parameters must exist:
•
The Supervised Analog Line (SAL) feature must be configured for each
lineside T1 port.
Содержание Circuit Card
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Страница 4: ...Page 4 of 906 Revision history 553 3001 211 Standard 3 00 August 2005...
Страница 18: ...Page 18 of 906 Contents 553 3001 211 Standard 3 00 August 2005...
Страница 78: ...Page 78 of 906 Overview 553 3001 211 Standard 3 00 August 2005...
Страница 100: ...Page 100 of 906 Acceptance tests 553 3001 211 Standard 3 00 August 2005...
Страница 156: ...Page 156 of 906 Option settings 553 3001 211 Standard 3 00 August 2005...
Страница 192: ...Page 192 of 906 NT4N39AA CP Pentium IV Card 553 3001 211 Standard 3 00 August 2005...
Страница 248: ...Page 248 of 906 NT5D11 and NT5D14 Lineside T1 Interface cards 553 3001 211 Standard 3 00 August 2005...
Страница 378: ...Page 378 of 906 NT5K21 XMFC MFE card 553 3001 211 Standard 3 00 August 2005...
Страница 384: ...Page 384 of 906 NT6D70 SILC Line card 553 3001 211 Standard 3 00 August 2005...
Страница 388: ...Page 388 of 906 NT6D71 UILC Line card 553 3001 211 Standard 3 00 August 2005...
Страница 533: ...NT8D02 and NTDK16 Digital Line cards Page 533 of 906 Circuit Card Description and Installation Figure 106 NTDK16 DLC...
Страница 544: ...Page 544 of 906 NT8D02 and NTDK16 Digital Line cards 553 3001 211 Standard 3 00 August 2005...
Страница 546: ...Page 546 of 906 NT8D03 Analog Line card 553 3001 211 Standard 3 00 August 2005...
Страница 564: ...Page 564 of 906 NT8D09 Analog Message Waiting Line card 553 3001 211 Standard 3 00 August 2005...
Страница 626: ...Page 626 of 906 NT8D14 Universal Trunk card 553 3001 211 Standard 3 00 August 2005...
Страница 680: ...Page 680 of 906 NT8D41AA Serial Data Interface Paddle Board 553 3001 211 Standard 3 00 August 2005...
Страница 694: ...Page 694 of 906 NT8D41BA Quad Serial Data Interface Paddle Board 553 3001 211 Standard 3 00 August 2005...
Страница 720: ...Page 720 of 906 NTAK09 1 5 Mb DTI PRI card 553 3001 211 Standard 3 00 August 2005...
Страница 734: ...Page 734 of 906 NTAK10 2 0 Mb DTI card 553 3001 211 Standard 3 00 August 2005...
Страница 744: ...Page 744 of 906 NTAK20 Clock Controller daughterboard 553 3001 211 Standard 3 00 August 2005...
Страница 762: ...Page 762 of 906 NTAK79 2 0 Mb PRI card 553 3001 211 Standard 3 00 August 2005...
Страница 768: ...Page 768 of 906 NTAK93 D channel Handler Interface daughterboard 553 3001 211 Standard 3 00 August 2005...
Страница 772: ...Page 772 of 906 NTBK22 MISP card 553 3001 211 Standard 3 00 August 2005...
Страница 844: ...Page 844 of 906 NTVQ01xx Media Card 553 3001 211 Standard 3 00 August 2005...
Страница 850: ...Page 850 of 906 NTVQ55AA ITG Pentium card 553 3001 211 Standard 3 00 August 2005...
Страница 884: ...Page 884 of 906 QPC841 Quad Serial Data Interface card 553 3001 211 Standard 3 00 August 2005...
Страница 906: ...Page 906 of 906 Appendix A LAPB Data Link Control protocol 553 3001 211 Standard 3 00 August 2005...
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