Network Control Method and Human-Machine Interface Design for ISDN Terminal

A human-machine interface is created for an Integrated Services Digital Network (ISDN) network control unit (I-NCU). I-NCU is a sophisticated terminal device that allows a voice communication channel and two data channels to he connected through an ISDN I-series interface. ISDN communication functions and network control opera- tions are analyzed to determine the required characteristics of I-NCU. I-NCU features the minimum number of control buttons and a liquid crystal display. Visual and audible information are used to keep the operator fully informed about the states of communication channels.