There is provided a multipurpose semiconductor integrated circuit device that can connect a variety of appliances to a network at low cost. The multipurpose semiconductor integrated circuit device includes: a plurality of types of input/output interfaces; a memory including a file storage region for a storing script file where processes relating to data inputted and/or outputted though the plurality of types of input/output interfaces are defined using a script language; an interpreter capable of executing the script files; and a file management system that admits accessing the file storage region of the memory thought at least one of the plurality of types of input/output interfaces. By defining user logic relating to input/output data using a script file, it is possible to clearly distinguish between firmware and user logic and user logic can be installed easily.