AlphaCom Audio Switching Hardware

This article contains a brief overview of the hardware involved in audio switching in an AICE Exchange Module. The first figure below shows the core elements of the infrasructure involved in audio switching.* All audio switching is controlled from the software on the Master Controller. It accesses the Audio Switching Control Registers in the SBI through the MBI and the Backplane Data Bus. Each board may have from one to eight SBI’s and each SBI has eight identical “Digital Audio Channels” or “Channels” for short. Audio travels through the system as 1Mbit/s line-switched digital signals. The backplane has 16 bus lines, each with 16 timeslots, giving a total switching capacity of 256 one-way audio signals per Exchange Module. The default modulation is Stentofon-modified 1Msample/s Σ∆-modulation.†