Improvements in or relating to a private automatic branch exchange (pabx) telephone system
Номер патента: IE62326B1
Опубликовано: 25-01-1995
Автор(ы): Declan Gibbons, Stephen Augustine Mcmahon
Принадлежит: ORANSAY Ltd
Опубликовано: 25-01-1995
Автор(ы): Declan Gibbons, Stephen Augustine Mcmahon
Принадлежит: ORANSAY Ltd
Реферат: A private automatic branch exchange (PABX) telephone system comprises: a power supply, an extension feed, an exchange circuit, a crosspoint switching matrix, a relay switch matrix, a ringing generator circuit, a dual tone multi-frequency (DTMF) receiver circuit, a call progress decoder (CPD), a microcomputer and a microcomputer control circuit. The ringing generator circuit includes a triac shunted across said circuit, the triac being operable to clamp any high inductive loads produced by a ringing bell when disconnected, thereby preventing high voltages being applied to the microcomputer. The DTMF receiver circuit includes means for polling "X" DTMF receivers between "X + Y" extensions. The polling means includes means for determining if a DTMF receiver is being utilised for manual dialling, and means, which on determination of the use of manual dialling, multiplex two extensions with said DTMF receiver. Also the polling means include means for interrogating the DTMF receivers in use for determining if an automatic dialling sequence is approaching a conclusion and means for reserving such a receiver for a particular extension.
Improvements in or relating to a private automatic branch exchange (pabx) telephone system
Номер патента: IE892970A1. Автор: Stephen Augustine Mcmahon,Declan Gibbons. Владелец: ORANSAY Ltd. Дата публикации: 1991-03-27.