Code:
exten => 9999,hint,Custom:example
exten => 19111,1,Set(DEVICE_STATE(Custom:example)=UNKNOWN)
exten => 19112,1,Set(DEVICE_STATE(Custom:example)=NOT_INUSE)
exten => 19113,1,Set(DEVICE_STATE(Custom:example)=INUSE)
exten => 19114,1,Set(DEVICE_STATE(Custom:example)=BUSY)
exten => 19115,1,Set(DEVICE_STATE(Custom:example)=INVALID)
exten => 19116,1,Set(DEVICE_STATE(Custom:example)=UNAVAILABLE)
exten => 19117,1,Set(DEVICE_STATE(Custom:example)=RINGING)
exten => 19118,1,Set(DEVICE_STATE(Custom:example)=RINGINUSE)
exten => 19119,1,Set(DEVICE_STATE(Custom:example)=ONHOLD)
exten => 19111,2,Goto(app-blackhole,hangup,1)
exten => 19112,2,Goto(app-blackhole,hangup,1)
exten => 19113,2,Goto(app-blackhole,hangup,1)
exten => 19114,2,Goto(app-blackhole,hangup,1)
exten => 19115,2,Goto(app-blackhole,hangup,1)
exten => 19116,2,Goto(app-blackhole,hangup,1)
exten => 19117,2,Goto(app-blackhole,hangup,1)
exten => 19118,2,Goto(app-blackhole,hangup,1)
exten => 19119,2,Goto(app-blackhole,hangup,1)