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3.3.4. FXS Setting
Dialing rules: see the dialing rules
Hotline: dial number when pull the phone
Key Hold: in the state of "Enable call", you can stop talking by pressing "*42"
Key Transfer: Enable and press *41, then input telephone number, you can achieve
Call transfer.
Call Hold: Enable it.
FXS+FXO Gateway Series
HTM-112
HTM-222
HTM-442
45