Abstract:
Various appliances linked up by a bus that can transmit video data form the system, and functionality modules themselves connected to the bus form certain appliances. A command enables to select functionality modules in various appliances at a time, to command the switch-on of these modules and to establish exchanges of data between these modules. A substantially virtual appliance may thus be formed by the combination of functionality modules that are found in separate appliances.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to an audiovisual system formed by various appliances of which certain appliances are formed by various functionality modules and are linked up by a bus, at least one of these appliances having a processor and receiving means for receiving commands from a user. 
     The invention also relates to an appliance intended to be part of an audiovisual system formed by various appliances of which certain appliances are formed by various functionality modules, the appliance including means for sending/receiving data over a bus, a processor and receiving means for receiving commands from a user. 
     The system as defined in the opening paragraph above is known from the document EP-A-0 580 211. According to this document, a domestic system comprises a plurality of separate appliances interconnected by a control network, and one of the appliances called hub appliance has actuators such as buttons which enable to activate whichever of the appliances from the hub appliance. 
     It is an object of the invention to augment the possibilities of such a system. 
     For this purpose, with the bus being capable of transmitting video data, the processor includes means for interpreting a command to combine modules and to select, in response to such a command, functionality modules in various appliances at a time, to command the switch-on of these modules and to establish data exchanges between these modules. 
     SUMMARY OF THE INVENTION 
     The invention is thus based on the idea of forming a substantially virtual appliance by the association of functionality modules that are found in separate appliances. 
     Particular embodiments will appear in the dependent claims  2  to  8 . 
     In an appliance for which the bus is of a model that can transmit video data, the processor includes means for receiving a command from a user requesting the processor to execute a particular function that implies the association of various functionality modules in separate appliances and means for sending over the bus, in response to such a command, selection commands of said modules, commands to switch-on these modules and commands to establish data exchanges between these modules. 
     These and other aspects of the invention are apparent from and will be elucidated, by way of non-limitative example, with reference to the embodiments described hereinafter. 
    
    
     
       In the drawings: 
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  diagrammatically represents an audiovisual system according to the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The audiovisual system of  FIG. 1  is formed by various appliances indicated by the term &lt;&lt;application&gt;&gt;. The appliance &lt;&lt;application 1&gt;&gt; comprises various functionality modules M1.1 to M1.n; the appliance &lt;&lt;application 2&gt;&gt; comprises various functionality modules M2.1 to M2.n, and so on. A bus SER.BUS capable of transmitting command data or information data and also video data interconnects these appliances. One or various functionality modules are linked up direct to the bus inside the appliances. This bus is, for example, a serial bus of the standardized type &lt;&lt;IEEE 1394&gt;&gt; whose rate can reach 400 Mbps. 
     The appliance &lt;&lt;application 1&gt;&gt; is, for example, a digital television receiver that has a processor μC 1  and means for receiving commands from a user, here a system known per se as a remote control formed by a remote-control emitter RCE which emits infrared light signals, and a receiver CR itself connected to the processor μC 1 . The functionality module M 1 . 1  is a graphics display; the functionality module M 1 . 2  is a tuner that receives digital television signals via a terrestrial antenna A. 
     The appliance &lt;&lt;application 2&gt;&gt; is, for example, a satellite television receiver/decoder also having a processor μC 2  and whose module M2.2 is a tuner that receives television signals via a satellite antenna S, the functionality module M2.5 is a decoder/descrambler and the functionality module M2.3 is a modem connected by a telephone line to a server (not shown) for managing payments of the user, for example, for watching a film. 
     The appliance &lt;&lt;application 3&gt;&gt; is, for example, a digital videorecorder having a processor μC 3  and of which a functionality module M 3 . 5  is a cassette read/write unit and another functionality module M3.2 is an analog tuner having an analog/digital converter. 
     The appliance &lt;&lt;application 2&gt;&gt; could also be, for example, a videoconference apparatus of which the functionality module M 2 . 3  is a modem and the functionality module M 2 . 4  is a television camera with microphone. 
     In the appliance &lt;&lt;application 3&gt;&gt;, the functionality module M3.5 could also be a DVD RAM or DVD RW reader/writer. 
     The appliance &lt;&lt;application 4&gt;&gt; is an area monitoring camera. 
     An appliance that has a processor can also be a personal computer connected to the audiovisual system as indicated under reference &lt;&lt;PC&gt;&gt;. It has a port for connection to the IEEE 1394 bus that links up the appliances of the system. 
     Each physical unit present on the bus may thus be subdivided into various sub-units or autonomous functionality modules. The moment a functionality module is linked to the digital bus, it becomes available to the other modules, even if the latter are located in different appliances. 
     In the appliance &lt;&lt;application 1&gt;&gt;, the processor μCl includes means, that is to say, software, for interpreting a command received from the user via the elements RCE and CR, and requesting a combination of the modules. In response to such a command, the processor selects functionality modules in various appliances at a time, it controls the switch-on of these modules and the establishing of data exchanges between these modules so as to realize the requested virtual appliance. Such a combination would not be possible without the bus. 
     Such a request may be of a variety of types, for example:
     combine the printer PR of the computer PC with a modem M 2 . 3  of the appliance &lt;&lt;application 2&gt;&gt; to form a facsimile machine, without the computer,   combine the graphics display M 1 . 1  of the appliance &lt;&lt;application 1&gt;&gt; with the modem M 2 . 3  of the appliance &lt;&lt;application 2&gt;&gt;to form a &lt;&lt;Minitel&gt;&gt;, or an Internet Surfer,   combine the modem M 2 . 3  with the recorder M 3 . 5  to purchase CD-ROMs on the &lt;&lt;Internet&gt;&gt; and record them locally,   combine the modules M 2 . 2 , M 2 . 5  and M 3 . 5  to receive and descramble transmissions and record them,   combine the analog tuner module M 3 . 2  having an analog/digital converter with the recorder M 3 . 5  to write analog transmissions on the DVD,   combine various cameras such as M 4 . 4  and the camera M 2 . 4  and the modem M 2 . 3  for a remote surveillance.   

     Although the product formed by these combinations is virtual, it is nevertheless necessary to execute its application somewhere. Various solutions are possible:
     the main display unit M1.1 having the processor μC 1  can behave as a computer and execute the application locally,   any other unit can behave like a master and control the other sub-units useful for the formation of the virtual product. In this case the television is only used for the interface with the user.   

     Such a virtual product may be introduced in an existing appliance:
     by remote-loading software via the satellite receiver, as an application of an electronic program guide,   by remote-loading software via &lt;&lt;Internet&gt;&gt;,   by means of a &lt;&lt;PC&gt;&gt; with its habitual means for loading programs,   by means of a digital videorecorder &lt;&lt;application 3&gt;&gt;, in which a suitable cassette or a DVD-ROM is loaded.   

     It is evident that other possibilities than those described above are also open, for example, the module M 3 . 2  may be a digital tuner, the appliance &lt;&lt;application 1&gt;&gt;an analog receiver in which the module M 1 . 2  is an analog tuner combined with an analog/digital converter, the modem may be a &lt;&lt;DECT&gt;&gt; or &lt;&lt;GSM&gt;&gt; radio transmission model, it may be located in the computer, and so on.