Patent ID: 8477328

Claim:
A function-providing system comprising: an information device, an added function-providing device and a controller, wherein the added function-providing device is connected to the information device and providing an added function to the information device, and wherein the controller controls operation of the information device and of the added function-providing device, wherein the information device comprises: a first module memory that stores at least one program module for executing a prescribed function, wherein at least one program module includes a first program module; and a first module executor that executes the program module stored in the first module memory; the added function-providing device comprises: a second module memory that stores at least one program module for executing the prescribed function, wherein at least one program module includes a second program module, wherein the second program module is identical to the first program module; and a second module executor that executes the program module stored in the second module memory; and the controller comprises: a selecting module that selects, from among program modules stored in the first module memory and the second module memory, at least one program module for executing the prescribed function, the selecting module selects either the first program module or the second program module when the prescribed function includes a function executed by the first program module and the second program module; and control module that makes the first module executor or/and the second module executor execute a program module selected by the selecting module, wherein the first module memory additionally stores first level information representing a selection hierarchy of program modules stored in the first module memory; the second module memory additionally stores second level information representing a selection hierarchy of program modules stored in the second module memory; and the selecting module selects, from the first program module and the second program module, the program module highest in the selection hierarchy, according to the first level information and the second level information.