Review Board 1.7.16

Dahdi FXS line polarity reversal when remote party Answers and/or Hangups

Review Request #797 - Created July 22, 2010 and submitted

Alec Davis
Quoting armeniki:
"FXS lines normally connect to a telephone. However, when FXS lines are routed to an external PBX or Key System to act as "external" or "CO" lines, it is extremely difficult, if not impossible for the external PBX to know when the call has been disconnected without receiving a polarity reversal on the line."

Implementation was to use existing keywords as used for FXO modules 'answeronpolityswitch' and 'hanguponpolarityswitch', with a similar function for the FXS module but from the Legacy PBX's point of view.
Using TDM800P FXS modules:

Inbound and outbound calls, using answeronpolarityswitch and hanguponpolarityswitch 
Review request changed
Updated (July 22, 2010, 1:05 p.m.)
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