ADTRAN 1202300L1, User Manual

Page: 46 / 54

Appendix B. Signalling States
B-4 FXS+ Quad Voice Option Module User Manual 61202300L1-1
The A and B signal bit states on the DS-1 signal are as fol-
lows:
Table B-4. FXS+ Mode (Ground Start)
FXS+2W
Input
RX A RX B TX A TX B FXS+2W Output
(Outgoing call from FXS+1)
No Ring Gnd
or Loop Open 1 1 0 1 Idle
Ring Gnd 1 1 0 0 No Tip Gnd
Ring Gnd or
Loop Closed
0 1 1 1 Tip Gnd
Loop Closed 0 1/0 0 1 Reverse Battery
Loop Open 0 1 0 1 Tip Gnd
Loop Open 1 1 0 1 Idle
(Incoming call to FXS+)
(Idle) 1 X - - No Tip Gnd & No Ringing
0 1 - - Tip Gnd & No Ringing
Loop Open 0 1 0 1 Tip Gnd & Ringing
Loop Closed 0 0 1 1 Tip Gnd & No Ringing
Signal Means
0 logic 0 is the DS-1 stream
1 logic 1 is the DS-1 stream
1/0 logic 1 followed by logic 0 in each
successive signalling frame
X value is not significant
Loop Open phone on-hook
Loop Closed phone off-hook