Local communication bus system and apparatuses for use in such a system

Claim 1

A local communication system comprising first, second and third apparatuses coupled to a serial data channel for the exchange of messages therebetween, wherein said first apparatus comprises first control means and said second apparatus comprises user interface means, and wherein said first control means comprises: a) first initiating means for initiating a user dialogue session with said second apparatus; b) first sending means for sending to said second apparatus a user information item for presentation to a user of the system during said user dialogue session; c) first receiving means for receiving from said second apparatus, information which conveys user control signals responsive to said user information item during said user dialogue session; d) second control means for controlling at least part of the system in accordance with said information; and e) second initiating means for initiating a transfer of control of said session to said third apparatus during said user dialogue session, and wherein said user interface means comprises: f) second receiving means for receiving from said first apparatus said user information item and for presenting said user information item to said user; g) third receiving means for receiving a control signal from said user during the user dialogue session; h) identifying means for identifying an association between said control signal and said user information item; and i) second sending means for sending to said first apparatus, information which conveys said control signal by reference to said user information item; and and wherein said third apparatus comprises: j) fourth receiving means for receiving said transfer of control of said user dialogue session from said second initiating means; and k) further control means for continuing said user dialogue session without active participation by said first control means.