The Digium X100P is a single port FXO (foreign exchange office) card whose job it is to interface an analog line from the phone company to your linux box. There are two variations of this card. The first consists of a Motorola chip and two small chips from Silicon Laboratories. The second card, also known as the x101p, consists of a Tiger Jet 320 chip and an updated Silicon Labs chip or chipset.
Wildcard disconnect issues
On non-US phone systems and where the Wildcard X100P is connected to a PBX or ISDN TA, it may not detect the end of a call. A frequent reason for this is that the Wildcard X100P expects a line voltage reversal – or at least a disconnect of line battery power – from the exchange in order to recognise call termination. This is not necessarily sent on lines other than standard PSTN lines. You can measure the line voltage with a voltmeter to see if you are getting the required pulse at the end of a call.
Options to look at include rebuilding the zaptel wcfxo.c driver defining the options for JAPAN or ZERO_BATT_RING (helps with some ISDN TAs). Alternatively you can enable software call progress detection although this itself may not work in every country.
April 7, 2023
Phone System 