Page 36 of 290
Description
553-3001-105
Standard 5.00
June 1999
Figure 13
Call connection sequence—near-end originating call
553-6146
High-
resistance
loop
Line card unit idle
(2-way voice
connection)
Remarks
Ground on tip/
battery on ring
Signal/direction
State
Meridian 1
Ground on tip/
battery on ring
High-resistance loop
Ground on tip/
battery on ring
Far-end station
on hook
Near-end station
on hook
If near-end station hangs up first, the following
occurs: Line card detects drop in loop current.
CPU removes timeslot assignments.
If far-end station hangs up first, the following
occurs: Meridian 1 detects disconnect signaling
from trunk. CPU removes timeslot assignments.
Person at near-end station recognizes end of
call and hangs up.
No battery current drawn.
Near-end station goes off hook. Battery current
is drawn causing detection of off-hook state.
CPU determines unit terminal number (TN) and
assigns message timeslots.
Low-resistance loop
Dial tone is applied to the near-end station from
the Meridian 1.
Call request
Dial tone
Addressing signals
Outpulsing
Near-end station dials number (loop pulsing or
DTMF tones).
Near-end
station
Dial tone
Meridian 1 detects start of dialing and
removes dial tone.
Ringback (or busy)
Meridian 1 decodes addressing, routes call, and
supplies ringback tone to near-end station if far-
end station is on hook. (Busy tone supplied if
far-end station is busy.)
When call is answered, ringback tone is
removed , and call is cut through to far-end
station.
Line card unit is ready for the next call.
High-
resistance
loop
Line card unit is ready for the next call.
High-resistance loop
Line card unit idle
Line card unit idle
High-
resistance
loop
Far-end
station
through
PSTN
Содержание NT1R20
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Страница 76: ...Page 52 of 290 Description 553 3001 105 Standard 5 00 June 1999 ...
Страница 98: ...Page 74 of 290 NT1R20 Off Premise Station Analog Line Card 553 3001 105 Standard 5 00 June 1999 ...
Страница 154: ...Page 130 of 290 NT5D11 Line side T1 Interface Card 553 3001 105 Standard 5 00 June 1999 ...
Страница 216: ...Page 192 of 290 NT5D33 and NTRB34 Line side E1 Interface Cards 553 3001 105 Standard 5 00 June 1999 ...
Страница 264: ...Page 240 of 290 QPC192 Off Premise Extension OPX Analog Line Card 553 3001 105 Standard 5 00 June 1999 ...
Страница 276: ...Page 252 of 290 QPC452 Basic 500 2500 Analog Line Card 553 3001 105 Standard 5 00 June 1999 ...
Страница 302: ...Page 278 of 290 QPC789 16 port Message Waiting Analog Line Card 553 3001 105 Standard 5 00 June 1999 ...
Страница 306: ...Page 282 of 290 List of terms 553 3001 105 Standard 5 00 June 1999 ...
Страница 314: ...Page 290 of 290 553 3001 105 Standard 5 00 June 1999 ...
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