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Description
553-3001-105
Standard 5.00
June 1999
Table 4
Loop Start Call Processing A/B Bit Settings
State
Transmit
Receive
A
B
A
B
Idle
0
1
0
1
Incoming Calls:
—
Idle
0
1
0
1
—
Ringing is applied from line-side T1 card
0
1/0
0
1
—
Terminal equipment goes off-hook
0
1/0
1
1
—
Line-side T1 card stops ringing
0
1
1
1
Outgoing Calls:
—
Idle
0
1
0
1
—
Terminal equipment goes off-hook
0
1
1
1
Call Disconnect from far end:
—
Steady state (call in progress)
0
1
1
1
—
Far end disconnects by dropping loop current and line-side
T1 card changes Transmit A bit to 1 momentarily.
1
1
1
1
—
Terminal equipment responds causing Receive A bit to
change to 0.
1
1
0
1
—
Line-side T1 responds by changing its Transmit A bit to 0.
Call is terminated and set to idle state.
0
1
0
1
Call disconnect from terminal equipment:
—
Steady state (call in progress)
0
1
1
1
—
Terminal equipment goes on-hook causing the Receive A bit
to change to 0. Call is terminated and set to idle state.
0
1
0
1
Summary of Contents for NT1R20
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Page 4: ...iv 553 3001 105 Standard 5 00 June 1999 iv ...
Page 12: ...xii Contents 553 3001 105 Standard 5 00 June 1999 ...
Page 76: ...Page 52 of 290 Description 553 3001 105 Standard 5 00 June 1999 ...
Page 154: ...Page 130 of 290 NT5D11 Line side T1 Interface Card 553 3001 105 Standard 5 00 June 1999 ...
Page 276: ...Page 252 of 290 QPC452 Basic 500 2500 Analog Line Card 553 3001 105 Standard 5 00 June 1999 ...
Page 306: ...Page 282 of 290 List of terms 553 3001 105 Standard 5 00 June 1999 ...
Page 314: ...Page 290 of 290 553 3001 105 Standard 5 00 June 1999 ...
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