Model and command set for an AV/C-based disc media player recorder

#The field of the present invention pertains to audio-video systems. More particularly, the present invention pertains to interfacing audio visual media devices via an IEEE 1394 bus using industry standard AV/C protocols.

#A typical home audiovisual equipment set up includes a number of components. For example, a radio receiver, a CD player, a pair of speakers, a television, a VCR, a tape deck, and alike. Each of these components are connected to each other via a set of wires. One component is usually the central component of the home audiovisual system. This is usually the radio receiver, or the tuner. The tuner has a number of specific inputs for coupling the other components. The tuner has a corresponding number of control buttons or control switches which provide a limited degree of controllability and interoperability for the components. The control buttons and control switches are usually located on the front of the tuner. In many cases, some, or all, of these buttons and switches are duplicated on a hand held remote control unit. A user controls the home audiovisual system by manipulating the buttons and switches on the front of the tuner, or alternatively, manipulating buttons on the hand held remote control unit.

#This conventional home audiovisual system paradigm has become quite popular. As the number of new consumer electronics devices for the home audiovisual system have grown and as the sophistication and capabilities of these devices have increased, a number of problems with the conventional paradigm have emerged. One such problem is incompatibility between devices in the home audiovisual system. Consumer electronic devices from one manufacturer often couple to an audiovisual system in a different manner than similar devices from another manufacturer.

#The present invention is illustrated by way of example and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:

#FIG. 1A shows a computer system environment of the present invention.

#FIG. 1B shows a home audio visual network in accordance with one embodiment of the present invention.

#Reference will now be made in detail to the embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of the present invention, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be obvious to one of ordinary skill in the art that the present invention may be practiced without these specific details. In other instances, well known methods, procedures, components, and circuits have not been described in detail as not to unnecessarily obscure aspects of the present invention.

#The present invention provides a device model which is disc media type independent and thereby supports any type of disc media (CD's, MiniDiscs, etc.). The present invention provides a model which supports enhancements to the AV/C protocol for content navigation and selection, providing both a detailed and a general abstraction of content discovery and description, and allowing for a range of controllers (from very simple to very complex) to make use of its features. The model of the present invention supports status reporting and notification mechanisms so that controllers are aware of what is occurring within the device, and thus keep the user informed. This capability is especially important in a distributed IEEE-1394 network environment where the device may be located away from the controller/user. In addition, the present invention provides a software based model and command set for a Disc player/recorder mechanism for multi-disc-type players capable of storing vast amounts of media content, thereby allowing any interested entity to navigate the contents of the media in the drive, to access the contents (such as the selection of a track on the disc), and to monitor the status of the drive. The present invention and its benefits are further described below.

#Some portions of the detailed descriptions which follow are presented in terms of procedures, steps, logic blocks, processing, and other symbolic representations of operations on data bits within a computer memory. These descriptions and representations are the means used by those skilled in the data processing arts to convey most effectively the substance of their work to others skilled in the art. A procedure, computer executed step, logic block, process, etc., are here, and generally, conceived to be self-consistent sequences of steps or instructions leading to a desired result. The steps are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated in a computer system. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like.