IP packet ready PBX expansion circuit for a conventional personal computer with expandable, distributed DSP architecture

摘要

A personal computer includes a PBX control program and one or more switch cards located in expansion board slots. The one or more switch cards are coupled to one or more port expansion units (PEU), which are coupled to telecommunication lines out to the various extension phones at the customer premises. Each PEU contains its own digital signal processor (DSP) so that distributed digital signal processing may be implemented to avoid any bottlenecks. One master PEU is coupled to a switch card by a time division multiplexed (TDMA) bus as well as a packet switched control bus, and all the other PEUs, if any, are coupled to the master PEU by extensions of the TDMA and packet switched buses. The TDMA bus carries PBX real time conversations while the packet switched bus carries control information, voicemail outbound message data packets, and inbound voicemail data packets.