ADTRAN 1202300L1, User Manual

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Appendix B. Signalling States
B-2 FXS+ Quad Voice Option Module User Manual 61202300L1-1
Ground start signalling provides its own tip ground in re-
sponse to ring ground in the Tandem Mode.
See Table B-2.
The A and B signal bit states on the DS-1 signal are as fol-
lows:
Table B-2. Tandem Modes
FXS+2W Input RX A RX B TX A TX B FXS+2W
Output Switch to FXS+
Condition
(Outgoing call from FXS+1)
Loop Open 0 X 0 0 _ Idle
Loop Closed 0 X 1 1 _ Idle
Loop Closed 1 X 1 1 Dial Tone Wink
Loop Closed 0 X 1 1 _ Wink Done
Loop Closed 1 X 1 1 _ Answer Far End
(Incoming call to FXS+)
Loop Open 0 X 0 0 Idle
Loop Closed 1 X 0 0 Ringing Far end off hook
Loop Closed 1 X 1 1 Answers Far end off hook
Signal Means
0 logic 0 is the DS-1 stream
1 logic 1 is the DS-1 stream
X value is not significant
Loop Open phone on-hook
Loop Closed phone off-hook