Data driven interaction for networked control of a DDI target device over a home entertainment network

Abstract

A method and system for providing a user interface for a networked target device within a home audio/visual network. The DDI allows any DDI target to describe its physical appearance including controls and displays, etc., to a DDI controller. The controller can be a remote physical device or can be a software program resident on the same or separate device as the target. The controller interfaces with the target to obtain the DDI data and generates a user interface for the target including: 1) interactive controls; and 2) user display information pertinent to the target. The DDI allows the controller to trigger actions on the target as if a user had physically manipulated the controls of the target. The controller and the target are connected to the same communication network. A particular embodiment operates within the HAVi architecture. The controller communicates with the user by using the input and output devices of (typically) the device upon which the controller is executing. This communication can be done in a controller-implementation-dependent manner. The target can be a DCM that controls its device in a implementation-dependent manner. The controller may be written in a generic manner that does not need to be implemented with knowledge of a particular target in mind; all target-dependencies are represented in the DDI data provided by the target to the controller.

Claims

What is claimed is:

1. In a network of electronic devices including a target and a plurality of controllers, a method of controlling said target comprising the steps of:

a) a controller requesting information from said target regarding controlling said target;

b) said target sending elements of a user interface to said controller, said target maintaining in memory a structured description of said user interface including organizational and non-organizational elements;

c) said controller generating said user interface based on said control elements and based on the display capabilities of said controller, said controller also allowing a user to interact with said user interface and sending user event messages to said target in response thereto;

d) said target interpreting said user event messages, and in response, altering an operational state of said target and generating a state change message for said plurality of controllers; and

e) said plurality of controllers updating their respective user interface based on said state change message from said target, said target thereby maintaining consistency among all of said plurality of controllers.

2. A method as described in claim 1 wherein said organizational elements define logically grouped functionality of said target and comprise panel elements and group elements.

3. A method as described in claim 1 wherein said non-organizational elements comprise a text element for representing a text string, a button element for representing a button and a choice element for representing a discrete set of possible input values.

4. A method as described in claim 3 wherein said non-organizational elements further comprise an entry element for allowing a user to enter a value and a range element for representing a predefined range.

5. A method as described in claim 1 wherein said step a) comprises the step of generating a message to said target requesting a root element identification.

6. A method as described in claim 1 wherein said controller includes a user input device and a display device for generating said user interface and wherein said method further comprises the steps of:

said target updating its operational state based on input that is not directly related to said user event messages; and

said target communication its updated operational state to said controller.

7. A method as described in claim 1 wherein said user event messages of said step c) each comprise an element identification and an action code and wherein said state change message of said step d) comprises an element identification and a state code.

8. A method as described in claim 1 further comprising the step of said controller subscribing to said target device for control thereof.

9. A method as described in claim 1 wherein said controller is a software program resident on a first electronic device.

10. A method as described in claim 9 wherein said target is a software program resident on a second electronic device.

11. In an audio/visual network of consumer electronic devices including a target means and a plurality of controller means, a system for providing networked control of said target means, said system comprising:

a) a controller means for requesting information from said target means regarding controlling said target means;

b) said target means for sending elements of a user interface to said controller means, said target means for maintaining in memory a structured description of said user interface including organizational and non-organizational elements;

c) said controller means also for generating said user interface based on said control elements and based on the display capabilities of said controller means, said controller means also for allowing a user to interact with said user interface and for sending user event messages to said target means in response thereto;

d) said target means also for interpreting said user event messages, and in response, altering an operational state of said target means and for generating a state change message for said plurality of controller means; and

e) said plurality of controller means also for updating their respective user interface based on said state change message from said target means, said target means thereby maintaining consistency of among all of said plurality of controller means.

12. A system as described in claim 11 wherein said organizational elements define logically grouped functionality of said target means and comprise panel elements and group elements.

13. A system as described in claim 11 wherein said non-organizational elements comprise a text element for representing a text string, a button element for representing a button and a choice element for representing a discrete set of possible input values.

14. A system as described in claim 13 wherein said non-organizational elements further comprise an entry element for allowing a user to enter a value and a range element for representing a predefined range.

15. A system as described in claim 11 wherein said step a) comprises the step of generating a message to said target means requesting a root element identification.

16. A system as described in claim 11 wherein said controller means includes a user input device and a display device for generating said user interface.

17. A system as described in claim 11 wherein said user event messages of said step c) each comprise an element identification and an action code and wherein said state change message of said step e) comprises an element identification and a state code.

18. A system as described in claim 11 wherein said controller means is a set-top-box unit.

19. A system as described in claim 11 wherein said audio/visual network is compliant with the HAVi architecture.

20. A system as described in claim 19 wherein said target means is a Device Control Module (DCM) software program resident on an electronic device.

21. A system as described in claim 19 wherein said target means is a software program resident on an electronic device.

22. A network of electronic devices comprising:

a common network bus;

a target coupled to said network bus; and

a plurality of controllers coupled to said network bus, wherein:

a controller generates a request to said target for information to control said target;

responsive to said request, said target operable to send said controller elements of a user interface, said target maintaining in memory a structured description of said user interface including organizational and non-organizational elements;

responsive to said elements and based on the display capabilities of said controller, said controller generating said user interface and allowing a user to interact therewith, said controller sending user event messages to said target;

said target interpreting said user event messages and based thereon altering an operational state of said target and for generating a state change message to said plurality of controllers in response thereto; and

said plurality of controllers operable to update their respective user interface based on said state change message from said target, said target thereby maintaining consistency among all of said plurality of controllers.

23. A network as described in claim 22 wherein said organizational elements define logically grouped functionality of said target and comprise panel elements and group elements and wherein said non-organizational elements comprise a text element for representing a text string, a button element for representing a button and a choice element for representing a discrete set of possible values.

24. A network as described in claim 22 wherein said user event messages each comprise an element identification and an action code and wherein said state change message comprises an element identification and a state code.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of consumer electronic devices. More specifically, the present invention relates to methods and systems for providing user interfaces for networked electronic devices including remote devices.

2. Related Art

The typical home entertainment system today consists of a variety of different consumer electronic devices which present and record audio/visual media in different ways. In the field of media devices, there is a spectrum of features for products of a given class (VCRs, video camera, etc.). Most of the features are represented by physical controls or elements on a control panel on the device which can be manipulated by a human user.

For instance, typical home audio-visual (AV) equipment includes a number of components such as a radio receiver or "tuner," a compact disk (CD) player and/or a digital video disc player (DVD), a number of speakers, a television, a video cassette recorder (VCR), a tape deck, and the like. Each of these components is connected to the others via a set of wires. One component is usually the central component of the home AV system; for example, the tuner. The tuner has a number of specific inputs for coupling the other components. Tuner-based control is often limited to connecting/disconnecting another component's AV input or output. The tuner has a corresponding number of control buttons or control switches which provide a limited degree of controllability and interoperability for the components. However, only rarely does a tuner control the component's operation (e.g., rewind, play, etc.). The control buttons and control switches are usually located on the front of the tuner providing the user with a so-called hard front panel interface. In many cases, some, or all, of these buttons and switches are duplicated on a hand-held remote control unit, another type of hard front panel interface. A user controls the home AV system by manipulating the buttons and switches on the front of the tuner or, alternatively, by manipulating buttons on the hand-held remote control unit. This conventional home AV system paradigm has become quite popular.

As consumer electronic devices become more capable and more complex, the demand for the latest and most capable devices has increased. As new devices emerge and become popular, the devices are purchased by consumers and "plugged" into their home AV systems. As a consumer purchases new devices (e.g., digital audio tape recorders, digital video disk players, digital camcorders, and the like), most often the new device is simply plugged into the system alongside the pre-existing, older devices (e.g., cassette tape deck, CD player, and the like). The new device is plugged into an open input on the back of the tuner or into some other device coupled to the tuner. The consumer (e.g., the user) controls the new device via the control buttons on the tuner, via the control buttons and control switches on the front of the new device itself, or via an entirely new and separate remote control unit for the new device.

As the number of new consumer electronic devices for the home AV 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 AV system. Consumer electronic devices from one manufacturer often couple to an AV system in a different manner than similar devices from another manufacturer. For example, a tuner made by one manufacturer may not properly couple with a television made by another manufacturer.

In addition, where one device is much newer than another device, additional incompatibilities may exist. For example, a new device might a incorporate hardware (e.g., specific inputs and outputs) which enables more sophisticated remote control functions. This hardware may be unusable with older devices within the AV system. Also, for example, older tuners may lack suitable inputs for some newer devices (e.g., mini-disc players, VCRs, etc.), or may lack enough inputs for all devices of the system. Another problem is the lack of functional support for differing devices within an AV system. For example even though a television may support advanced sound formats (e.g., surround sound, stereo, etc.), if an older and less capable tuner does not support such functionality, the benefits of the advanced sound formats can be lost.

Another problem is the proliferation of controls for the new and differing devices within the home AV system. For example, similar devices from different manufacturers can each have different control buttons and control switch formats for accomplishing similar tasks (e.g., setting the clock on a VCR, programming a VCR record a later program, and the like). In addition, each new device coupled to the AV system often leads to another dedicated remote control unit for the user to keep track of and learn to operate.

To address the problems above, a home AV network has been proposed for consumer electronic devices, including computing devices (e.g., personal computers and peripheral devices such as printers). The home AV network would provide a set of services which facilitate device interoperability and allow the devices to cooperate to perform application tasks. By connecting consumer electronic devices in a home AV network, it is also possible to share processing and storage resources. In addition, a home AV network allows consumer electronic devices to be coordinated and simultaneously controlled by a user, thereby simplifying that aspect of operation from the user's perspective. The underlying structure of a home AV network consists of a set of interconnected clusters of devices. Typically, there may be more than one cluster in a home, perhaps one per floor or one per room. Each cluster functions as a set of interconnected devices to provide services to a single user or to multiple simultaneous users.

Recently, a class of consumer electronic media devices has been proposed that can be networked together using a particular type of network using a standard communication protocol layer, e.g., IEEE 1394 communication standard. The IEEE 1394 standard is an international standard for implementing an inexpensive high-speed serial bus architecture which supports both asynchronous and isochronous format data transfers. The IEEE 1394 standard provides a high-speed serial bus for interconnecting digital devices thereby providing universal input/output connection. The IEEE 1394 standard defines a digital interface for applications thereby eliminating the need for an application to covert digital data to an analog form before it is transmitted across the bus. Correspondingly, a receiving application will receive digital data from the bus, not analog data and will therefore not be required to convert analog data to digital form. The IEEE 1394 is ideal for consumer electronics communication in part because devices can be added to or removed from the serial bus while the bus is active. If a device is so added or removed, the bus automatically reconfigures itself for transmitting data between the then existing devices. Each device on the bus is a "node" that has its own address on the bus and contains its own address space. Each node connected to the bus is capable of communicating with any other node also on the bus.

The provision of the IEEE 1394 serial communication bus for networking consumer electronic devices has introduced a powerful new platform on which device functionality and inter-operability can be built. For instance, in such a system, complex operations involving media transfers, media recordings and media presentation can be performed that involve two or more devices acting in concert. However, interaction between these devices can be complex, error prone and laborious if it is required that each device be directly touched in order to properly configure the desired operation. The problems associated with properly configuring the media operation can be exacerbated if one or more of the devices are remotely located and/or need constant attention and or adjustment. What is needed is an effective mechanism for interfacing with networked consumer electronic devices to facilitate media operations between two or more devices.

The physical separation between devices in a home AV network introduces a problem regarding control of a particular device. A user may be trying to remotely control a device that is physically separated from the user and thus is not able to be seen. For example, a VCR on the home AV network may be in one room, while the user is in another room containing the television. Therefore, the user is not sure whether he/she entered in the proper commands and that the device is correctly performing the desired function.

Another problem is introduced when there are multiple users simultaneously on the home AV network, each user working from a separate location. Thus, continuing the example above, more than one user may be attempting to control the VCR. Each user, not aware of the fact that there is another user also trying to use the VCR, will be entering commands that are perhaps conflicting and that are not being carried out properly. In addition, each user will not have information regarding the status of the VCR (e.g., whether the VCR is recording or playing), and thus will not be aware of whether they successfully entered the proper commands and whether the device is performing the desired function.

In addition, it is often desired to provide remote control access to the features performed by a consumer electronic device so that these devices can be accessed from a central location within a home or office. However, not all consumer electronic devices are able to provide a sophisticated display system for remote interaction, e.g., some devices offer only a small liquid crystal display (LCD) or a small collection of light emitting diodes (LEDs) as display devices. What is needed is a mechanism for interfacing remotely with devices that provides a sophisticated level of user interaction for devices of differing local display capability. Also, in many consumer electronic systems, each device can have its own remote control unit. In systems having even a modest amount of devices, the user discovers that three or more different and bulky remote control devices are required to perform media operations. What is needed is a mechanism for interfacing with electronic devices that reduces the problems of having different remote control units for different devices. What is needed further is a mechanism for interfacing with electronic devices that is flexible and can adapt to new devices and device types within the consumer electronics market.

SUMMARY OF THE INVENTION

Accordingly, the present invention provides an effective mechanism for interfacing with networked consumer electronic devices to facilitate media operations between two or more devices. The present invention also provides a mechanism for interfacing remotely with devices and that provides a sophisticated level of user interaction for many devices that themselves may have limited display capability. The present invention also provides a mechanism for interfacing with electronic devices that operates using a remote controller and a central display for instructing different electronic devices and for receiving status information regarding the different electronic devices. The present invention provides an interface mechanism for interfacing with electronic devices that is additionally flexible and can adapt to new devices and device types within the consumer electronics market. The present invention provides the above advantageous features within one embodiment that is compliant with the Home Audio/Visual Interoperability (HAVi) architecture. These and other advantages of the present invention not specifically mentioned above will become clear within discussions of the present invention presented herein.

A method and system are described herein for providing a user interface for a networked electronic device using a data driven interface (DDI) including a data structure of information maintained between a DDI target device and a DDI controller. The present invention utilizes the DDI to allow any compliant device (e.g., a DDI target device) to have the physical appearance of its controls and displays (e.g., elements) represented by a data structure used by another device (e.g., a DDI controller) and allows the DDI controller to thereby trigger actions on the DDI target device as if a user had directly physically manipulated the controls on the DDI target device. The present invention operates within a network of consumer electronic devices, e.g., television (TV), set-top-box, video cassette recorder (VCR), compact disk (CD) device, personal computer system (PC), etc., that are coupled together using a standard communication protocol layer, e.g., the IEEE 1394 serial communication standard. A DDI controller (e.g., a TV or set-top-box or computer system or other intelligent electronic device) monitors the network to discover the units coupled thereto and is programmed to locate DDIs that are defined for a DDI target device. The DDI target device may be remotely located. In one embodiment, the network is compliant with the HAVi architecture.

In general, the DDI provides the DDI controller with information for rendering a depiction of the controls and displays of the DDI target device and this depiction can be interacted with by a user for remotely triggering actions by the DDI target device. The DDI is defined such that command interpretations and image alterations are controlled by the DDI target device thereby reducing the responsibility of the DDI controller in managing the user interface with generic user events. This approach allows increased flexibility to expand the user interface and adjust to future control types and display information protocols.

The DDI uses graphical user interface (GUI) "elements" stored in a data structure to define the physical controls of the DDI target device. The GUI elements include standard types of controls and displays (e.g., push buttons, toggles, sliders, dials, LCD screens, alphanumeric inputs, etc.) that are commonly found on consumer electronic devices. The control types have well defined behaviors (e.g., buttons are pushed, dials are moved, values are input, etc.). In addition, the DDI defines a set of "user events" which can be applied to any of these controls by the user. The user events are defined to be sufficiently generic so that they apply to most types of controls. The purpose of these generic user events is to encapsulate the typical user manipulated action for the GUI elements and to let the DDI target device decide the manner in which to interpret the user actions on its own thereby relieving the DDI controller of these responsibilities. Related elements of a DDI target device can be organized together into logical groups which the DDI allows to be displayed or processed together in special ways. The DDI controller is responsible for the exact visual appearance of the GUI elements and their exact layout on its display.

The internal state of the DDI target is maintained by the DDI target which keeps the DDI controller informed of its status. The DDI target forwards status update messages (upon changes of state) to the DDI controller to update its graphical display for the user. A status notification commands also allows the DDI controller to poll the DDI target for changes in state.

A particular embodiment of the present invention operates within the HAVi architecture. Using the DDI mechanism, a HAVi software element can provide a user with the ability to control another software element. Within this interaction, the first software element is termed the DDI controller and the second software element the DDI target. The DDI controller uses a description of the User Interface (UI) to be presented to the user and is obtained from the DDI target. The means by which this control is accomplished is described herein.

In this particular embodiment, the DDI controller and its DDI target are both HAVi components each executing on an IAV or FAV device. The components may be on the same or different devices, implemented using native code or Java bytecode; in all cases, though, they interact by sending HAVi messages to each other. The DDI controller communicates with the user by using the input and output devices of (typically) the device upon which the controller is executing. This input/output communication can be done in a controller-implementation-dependent manner. The DDI target can be a DCM that controls its device in a implementation-dependent manner. The HAVi DDI protocol described herein is structured so that a DDI controller may be written in a generic manner. That is, a DDI controller does not have to be implemented with knowledge of a particular DDI target in mind; all target-dependencies are represented in the DDI data provided by the target to the controller.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an exemplary networked system of electronic devices including a video camera, a video cassette recorder, a computer, a set-top-box, a television and a compact disk changer.

FIG. 2 illustrates exemplary components of a DDI controller device in accordance with the present invention.

FIG. 3 is a logical diagram of a networked system in accordance with the present invention including one or more DDI controllers and a DDI target device.

FIG. 4A is a perspective view of a DDI target device having a physical panel display elements and panel control elements.

FIG. 4B is a perspective view of the DDI target device of FIG. 4A having a front panel in the flipped-open state to expose more physical control and display elements.

FIG. 5 illustrates a logical block diagram of the logical partitions or "subunits" located within a DDI target device (a VCR) including the DDI of the present invention.

FIG. 6 is an illustration of the communication interface between a DDI target and a DDI controller in accordance with the present invention.

FIG. 7 is a diagram illustrating an exemplary GUI displayed on a DDI controller in response to a target's DDI defined in accordance with the present invention.

FIG. 8A illustrates an exemplary generic DDI hierarchy, including panels, objects and non-organizational GUI elements, defined in accordance with the present invention.

FIG. 8B illustrates an exemplary specific DDI hierarchy, including panels, objects and specific non-organizational GUI elements, defined in accordance with the present invention.

FIG. 9A is a flow diagram illustrating a process used by a DDI controller and a DDI target for rending a GUI on the DDI controller in response to the target's DDI.

FIG. 9B is a flow diagram illustrating the steps performed by the DDI controller of FIG. 9A in response to a user interaction with the controller's GUI and in response to the DDI target's state change messages.

FIG. 9C is a flow diagram illustrating the steps performed by the DDI target of FIG. 9A in response to user event messages from the DDI controller and in response to interaction with the target's own physical input device (if present).

FIG. 10 is a flow diagram illustrating the steps performed by the present invention for displaying and presenting a representation of a panel as defined by the DDI of the present invention.

FIG. 11 is a flow diagram of the panel and group representation in accordance with the present invention.

FIG. 12 is a flow diagram of the element representation in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description of the present invention, a data driven interface (DDI) for allowing a DDI controller device to remotely interface with a DDI target device within a network of consumer electronic devices, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be recognized by one skilled in the art that the present invention may be practiced without these specific details or with equivalents thereof. 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 is drawn to a DDI that allows any compliant device (e.g., "DDI target device") to describe its physical appearance including controls and displays, etc., to a DDI controller. The DDI controller can be a remote physical device or can be a software program resident on the same or separate device as the DDI target. The DDI controller interfaces with the DDI target to obtain the DDI data and generates a user interface for the DDI target device including: 1) interactive controls; and 2) user display information pertinent to the DDI target device. The DDI allows the DDI controller to trigger actions on the DDI target device as if a user had physically manipulated the controls of the DDI target device. The DDI controller and the DDI target device are connected to the same communication network (e.g., using the IEEE 1394 serial standard). The present invention can also be used in one embodiment to promote high levels of inter-operability between any of the devices.

Generally, the present invention allows the DDI controller to communicate with the DDI of the DDI target device and inquire about the various types of controls which it has, e.g., buttons, dials, sliders, etc., which are represented as graphical user interface (GUI) elements within the DDI. The DDI controller then generates, on its display, a user interface based on these control object descriptions, and when the user manipulates this user interface, the controller sends special user events to the DDI target device. The information that is capable of being displayed by the DDI controller can be made scaleable by the DDI target device so that the human interface displayed can adapt to the particular display capabilities of the DDI controller device. The DDI controller monitors the DDI target device to maintain the most current status presented to the user.

The DDI controller does not need to have advance knowledge of any specific features in the DDI target device or how they are used or invoked because this functionality is the responsibility of the DDI target device. All issues such as state transitions and inter-control dependencies are handled automatically the by DDI target device independently of the DDI controller. The present invention removes all requirements for items such as state transition tables and their execution environment, because it takes advantage of the functionality that is already built into a media device and used to handle the physical buttons as they are manipulated by the user. For instance, when the DDI controller asks the target to "simulate the press of button 5," the DDI controller does not need to have any knowledge at all about what is happening within the DDI target device upon being notified of the user action. The state transition logic for what happens when "button 5" is pressed is all contained within the DDI target device. This is advantageous because it enhances the inter-operability between the DDI controller and the DDI target device while at the same time greatly reduces the responsibilities of each.

In addition to describing physical controls and appearances, the present invention can be used to describe logical controls and appearances of elements of a logical control panel. For instance, a logical control panel can be used to control a "black box" not having any physical controls but having only a 1394 connector with the black box being located in a closet or other remote location. In this case, the black box is manipulated with on screen controls via its DDI thereby having no physical control panel itself.

NETWORK ENVIRONMENT OF THE PRESENT INVENTION

FIG. 1 illustrates an exemplary network system 5 that can support the embodiments of the DDI of the present invention. Exemplary system 5 includes consumer electronic devices (including computer systems) as nodes but could be extended equally well to cover other electronic devices. In one embodiment, system 5 is compliant with the HAVi architecture. System 5 includes a video camera 10, a video cassette recorder (VCR) 12, a computer system 14, a set-top-box (STB) 13, a television set (TV) 11 and a compact disk (CD) changer 20 connected together with the network by IEEE 1394-1995 (IEEE 1394) cables 15, 16, 18 and 19. It is appreciated that the DDI embodiments of the present invention are equally well suited for application with any bus structure and the IEEE 1394 bus structure is shown and described herein as an example bus architecture only. The STB 13 can be coupled to receive media from a cable TV system. The IEEE 1394 cable 16 couples the video camera 10 to the VCR 12 allowing the video camera 10 to send data, commands and parameters to the VCR 12 for recording (or to any other device of the network 5). The IEEE 1394 cable 18 couples the VCR 12 to the computer system 14 allowing the VCR 12 to send data, commands and parameters to the computer system 14 for display (or to any other device of the network 5).

The IEEE 1394 cable 15 couples the STB 13 to the computer system 14. The STB 13 is also coupled to the TV 11 by the cable 17. The CD changer 20 is coupled to the TV 11 by the IEEE 1394 cable 19. The configuration 5 illustrated in FIG. 1 is exemplary only and it should be apparent that an audio/video network in accordance with the present invention could include many different combinations of components. The devices within an IEEE 1394 network 5 are autonomous devices, meaning that in an IEEE 1394 network, in which a computer is one of the devices, there is no true master-slave relationship between the computer system 14 and the other devices. In fact, as described below in an exemplary embodiment of the DDI of the present invention, the DDI controller is the STB 13. In many IEEE 1394 network configurations, a computer system 14 may not be present. Even in such configurations, the devices within the network are fully capable of interacting with each other on a peer-to-peer basis. It should be recognized that data, commands and parameters can be sent between all of the devices within the IEEE 1394 network 5.

The IEEE 1394 serial bus used by system 5 of FIG. 1 is a high-speed bus architecture for interconnecting digital devices thereby providing a universal input/output connection. The IEEE 1394 standard defines a digital interface for the applications thereby eliminating the need for an application to covert digital data to analog data before it is transmitted across the bus. Correspondingly, a receiving application receives digital data from the bus, not analog data, and therefore is not required to covert analog data to digital data. The cable required by the IEEE 1394 standard is very thin in size compared to other bulkier cables used to connect such devices. Devices can be added and removed from an IEEE 1394 bus while the bus is active. If a device is so added or removed, the bus automatically reconfigures itself for transmitting data between the then existing nodes. A node is considered a logical entity having a unique address on the bus structure. Each node provides an identification ROM, a standardized set of control registers and its own address space.

The IEEE 1394 communication standard within system 5 of FIG. 1 supports isochronous data transfers of digital encoded information. Isochronous data transfers are real-time transfers which take place such that the time intervals between significant instances have the same duration at both the transmitting and receiving applications. Each packet of data transferred isochronously is transferred in its own time period. An example of an application for the transfer of data isochronously is from a VCR 12 to TV 11 of FIG. 1. The VCR 12 records images and sounds and saves the data in discrete packets. The VCR 12 then transfers each packet, representing the images and sounds recorded over a limited time period, during that time period, for display by the TV 11. The IEEE 1394 standard bus architecture provides multiple channels for isochronous data transfers between applications. Specifically, a six bit channel number is broadcast with the data to ensure reception by the appropriate application. This allows multiple applications to simultaneously transmit isochronous data across the bus structure. Asynchronous transfers are traditional data transfer operations which take place as soon as possible (however, unlike isochronous transfers, with no restrictions on time in transit) and transfer an amount of data from a source to a destination.

DDI CONTROLLER

As described below, the DDI controller is shown as a hardware element. However, it is appreciated that the DDI controller (as well as the DDI target device), within the scope of the present invention, can also be a software element that operates within the hardware platform as described below.

User interface aspects of the DDI of the present invention are implemented within a DDI controller device. The DDI controller can be any device coupled within a networked system (e.g., system 5 of FIG. 1) designated by the user and having certain basic input functionality and basic display capability. In one embodiment of the present invention, the STB 13 and the TV 11 act as the DDI controller. In other embodiments, the computer system 14 can act as the DDI controller or the TV 11 can act alone as a DDI controller. Any device having "display" and input capability can act as the DDI controller, e.g., a personal digital assistant (PDA), a hand-held electronic device, a cell phone, etc.). Within the context of the present invention, the DDI controller is the device that provides a user interface for controlling events on another, remote, DDI target device within the network 5. To this extent, the DDI controller communicates with a display device and an information input device. The display and input capabilities of the DDI controller device define the type of user interface that the DDI controller can provide to a user and the DDI of the present invention allows the definition of scaleable user interface capabilities.

FIG. 2 illustrates the components of the DDI controller, and in this example it is the STB 13. STB 13 includes an address/data bus 100 for communicating information, a central processor 101 coupled with the bus 100 for processing information and instructions, a volatile memory 102 (e.g., random access memory RAM) coupled with the bus 100 for storing information and instructions for the central processor 101 and a non-volatile memory 103 (e.g., read only memory ROM) coupled with the bus 100 for storing static information and instructions for the processor 101. STB 13 can also optionally include a data storage device 104 ("disk subsystem") such as a magnetic or optical disk and disk drive coupled with the bus 100 for storing information and instructions. In one embodiment, the display device 105 can be part of the DDI controller. As shown in FIG. 2, the display device (e.g.,. TV 11) is external to the STB 13. When incorporated into the DDI controller, the display device 105 can be a display screen (e.g., flat panel or CRT, etc.) or it can be a liquid crystal display (LCD) panel or other suitable display device for the display of alphanumeric and/or graphic information.

The DDI controller 13 also interfaces with or includes one or more user input devices. In one embodiment, the input device can be a button or dial (or toggle or rocker switch) input device 106 which can include alphanumeric and function keys coupled to the bus 100 for communicating information and command selections to the central processor 101. Alternatively, or in addition, the DDI controller 13 can interface with or include a cursor control or cursor directing device 107 coupled to the bus for communicating user input information and command selections to the central processor 101. The cursor directing device 107 can be implemented using a number of well known devices such as a mouse, a track ball, a track pad, an electronic pad and stylus, an optical tracking device, a touch screen etc. In addition, the user input device 107 can also be a remote control device, e.g., a universal remote control device having a number of buttons, dials, etc., with an infra-red signal communication capability. STB 13 can also include a signal generating device 108 ("bus interface") coupled to the bus 100 for interfacing with other networked devices over the IEEE 1394 bus, e.g., line 15 and/or line 17.

The DDI target device of the present invention can exist as a hardware device and in this manner can also include one or more components as described with respect to FIG. 2. Particularly, the DDI target device in accordance with the present invention includes computer readable memory units which can include one or more ROM and/or RAM units for storing DDI information of the present invention which are described below. The DDI target can also be realized as a software element.

DDI SYSTEM OF THE PRESENT INVENTION

FIG. 3 illustrates a logical diagram of a DDI target device 210 being controlled by and communicating with one or more DDI controllers 220. Also shown in FIG. 3 is the DDI target device's own physical control panel 204 (optional) which can also provide control for the DDI target device 210 as well as other third party elements 202. A HAVi software element can provide a user with the ability to control another software element using the HAVi DDI mechanism. Within this interaction, the first software element is termed the DDI controller 220 ("controller") and the second software element the DDI target 210 ("target"). The DDI controller 220 uses a description of the user interface (UI) to be presented to the user. This is called the DDI data and is obtained from the DDI target 210. The means by which this control is accomplished is described herein. More than one logical subunit can exist within a target device 210 (see FIG. 5). Each subunit can be controlled by its own DDI controller 220 therefore multiple DDI controllers 220 can be linked to the same target device 210 as shown in FIG. 3.

Within one embodiment of the present invention, the DDI controller 220 and its DDI target 210 are both HAVi components each executing on an IAV or FAV device. The components may be on the same or different devices, implemented using native code or Java bytecode; in most cases, they interact by sending HAVi messages to each other. The DDI controller 220 communicates with the user by using the input (e.g., 106 and 107) and output devices (e.g., 105) of the platform upon which the DDI controller 220 is executing, e.g., when the DDI controller 220 is a software element. This input/output (I/O) communication can be done in a controller-implementation-dependent manner. The DDI target 210 can be a DCM that controls its device in an implementation-dependent manner. The HAVi DDI protocol is structured so that a DDI controller 220 can be written in a generic manner. That is, a DDI controller 220 does not have to be implemented with knowledge of a particular DDI target 210 in mind; all target-dependencies are represented in the DDI data provided by the target device 210 to the DDI controller 220.

The HAVi DCM, IAV and the FAV elements are described in the following copending patent applications which are all assigned to the assignee of the present invention and hereby incorporated by reference: application Ser. No. 09/003,119, now U.S. Pat. No. 6,032,202, filed on Jan. 6, 1998, entitled "A Home Audio/Video Network with Two-Level Device Control Modules," by Lea and Ludtke; application Ser. No. 09/003,097, now U.S. Pat. No. 6,349,352, filed on Jan. 6, 1998, entitled "Home Audio/Video Network with Both Generic and Parameterized Device Control," by Lea; application Ser. No. 09/003,112, now U.S. Pat. No. 6,052,750, filed on Jan. 6, 1998, entitled "A Home Audio/Video Network with Updatable Device Control Modules," by Lea; and application Ser. No. 09/003,111, now U.S. Pat. No. 6,038,625, filed on Jan. 6, 1998, entitled "Method and System for Providing A Device Identification Mechanism within a Consumer Audio/Video Network," by Ogino and Zou.

The DDI is defined for a DDI target device and outlines characteristics for generating a user interface on the DDI controller 220. The DDI can be defined for multiple DDI target devices and therefore many DDIs can be included within a network system 5. For a particular DDI target device, its DDI can be stored as a data structure within computer readable memory units of the particular DDI target device 210.

FIG. 4A illustrates a perspective view of the VCR of FIG. 1 as an exemplary DDI target device 210. Although, generally, any electronic device can have its own DDI and thereby be a "DDI target device," the following discussion illustrates an exemplary case where the VCR is the DDI target device 210. The VCR contains a video tape slot 212 for insertion and removal of video tape media. The VCR also contains one or more liquid crystal displays (LCDs) 214.

FIG. 4B illustrates the VCR target device 210 with a control panel 220 flipped-down exposing certain controls and further displays (e.g., "elements"). The control panel 222 contains another LCD display 240 and includes a scrubber control 230 or "dial." The control panel 222 also contains certain tape transport controls 250 (including play, pause, stop, rewind, fast-forward, buttons etc.). When the control panel 222 is flipped down, it exposes tuner preset buttons 225. In the present invention, devices can have more than one logical control panel. In this configuration, the VCR has two logical subpanels. The first subpanel includes the controls and display of the flip-down control panel 222 and the second subpanel includes the tape slot 212 and the tuner preset buttons 225. Another subpanel could define the LCD panel 214.

FIG. 5 illustrates a logical block diagram of some of the subunits that can be associated with the VCR target device 210 in accordance with the present invention. Within the well known AV/C protocol, subunits are logical, not physical, groupings of functionality that can be individually addressed and controlled within a device. For example, a VCR device can have two subunits, one subunit 312 for the actual VCR tape transport mechanism, and another subunit 320 for the tuning functionality. The DDI 314 of the present invention adds a novel logical subunit that can be associated with the VCR device. As described further below, the DDI 314 of the present invention is realized, in one embodiment, as one or more data structures stored in computer readable memory units of the DDI target device e.g., the VCR. It is possible for a DDI for a first device (e.g., of limited memory capacity) to exist on a second device (having more memory), whereby the second device acts as a proxy for the first device's DDI.

The DDI 314 is a collection of data structures that describe the physical controls on the DDI target device (e.g., the control panel) 210. In operation, the DDI controller (e.g., STB 13) 220 accesses the DDI 314 of the DDI target device 210, and based thereon, implements a user interface for controlling the DDI target device 210 (e.g., the VCR 12). The user interface involves the display (e.g., TV 11) and user input devices associated with the DDI controller 220. The specification for the DDI 314 defines several standard types of controls and displays that are commonly found on consumer electronic devices, such as push buttons, sliders, dials, LCD screens, etc. As an example, the descriptions within the DDI 314 for VCR 12 could represent the buttons, dial and LCD screens of FIG. 4A and FIG. 4B.

The element types defined by the DDI 314 have well defined behaviors. For instance, buttons are pushed and released and typically have two values, sliders may have several discrete values or a continuous range of values. Further, some standard control types may be combined within the descriptors to form hybrid or custom controls. One example of this is a dial with a push button in the middle or a button with an LED in the middle. Such composite control mechanisms are supported by the DDI of the present invention. Finally, vendor specific custom controls may also be defined.

In addition to standard control types, the DDI 314 of the present invention also defines a set of commands which may be applied to any of these controls. The commands are defined to be sufficiently generic so that they apply to most types of controls. For example, issuing the command SET CONTROL VALUE (control 1, 6) by the DDI controller 220 may cause a volume slider to be set to the value 6, representing a change in volume. Likewise, the same command type with different operands can be issued as SET CONTROL VALUE (control 5, "please enter the track name"), and it would cause that text to show upon the LCD display of a MiniDisc recorder 20, prompting the user to enter a name for a track on the disc. Further, within the DDI, some commands can be specific to certain kinds of controls.

The DDI 314 also defines "user events" which can be applied to the controls of the user interface. The purpose of these generic user events is to encapsulate the typical user manipulation actions for controls, and to let the DDI target device interpret what it means when these user events occur thereby freeing the DDI controller 220 of this responsibility. For example, many CD players 20 have multiple semantic meanings for the fast forward button on the device and these meanings are affected by the current state of the device. Consider the following:

    TABLE I
    Current Device Setting Action            Result
    Device Is Not Playing FF Button Pressed Advance to the Next
                                         Track and Hold
    Device Is Playing  FF Button Pressed Advance to the Next Track
                                         and Continue Playing from
                                         that Point
    Device Is Playing  FF Button Pressed Play in "Fast Forward"
                       and Held Down     Mode

                             TABLE II
                        Services Provided
                                  Comm
    Service                       Type   Locality Access
    DDITarget::SubscribeGui         M    global  DDI controller
    DDITarget::UnsubscibeGui        M    global  DDI controller
    DDITarget::GetGuiElement        M    global  all
    DDITarget::GetGuiPanelList      M    global  all
    DDITarget::GetGuiGroupList      M    global  all
    DDITarget::GetGuiElementList    M    global  all
    DDITarget::UserAction           M    global  DDI controller
    DDIController::NotifyGuiChange    N    global  DDI target
                                                 (DDI controller)

                  //GuiElementId Representation
            //Syntax             Nb of bits      Identifier
            GuiElementId() {
            GuiElemType              8           uimsbf
            GUIElementHdl            16          uimsbf
            }

    typedef ushort GuiElementId;
    typedef sequence<GuiElementId> GuiElementIdList;
    typedef sequence<GuiElement> GuiElementList;
    typedef ushort GuiContentId;
    typedef octet Color[3];     // R,G,B true color
    typedef octet Color[COLORLENGTH];   // length to be defined
    typedef sequence<octet> Bitmap;  // variable size
    typedef sequence<octet> Sound;   // variable size
    typedef sequence<char> Label;
    typedef ushort Relation;
    typedef short Font;
    typedef Channel AudioVideo;
       // stream manager iso channel media
       // channel definition is in Stream
       // Manager section
    enum Selectable {SET, UNSET};
    struct Pattern {
      ushort height;
      ushort width;
      GuiContentId Bitmap pattern_bitmap;
    }

        struct FocusNavigation {
          GuiElementId up;       GuiElementId down;
          GuiElementId left;     GuiElementId right;
        }
        typedef GuiContentId Title; // smaller than 10% of safety area
        sizetypedef Bitmap Title; // size to be defined
         struct Date {
         unsigned short Year;    // e.g. 1998
         unsigned short Month;   // 1 to 12
         unsigned short Day;     // 1 to 31
         unsigned short Hour;    // 0 to 23
         unsigned short Minute;  // 0 to 59
         unsigned short Second;  // 0 to 59
        }
        struct Time {
         unsigned short Hour;    // 0 to 23
         unsigned short Minute;  // 0 to 59
         unsigned short Second;  // 0 to 59
        }

            (decimal)              137 72 65 86 105 13 10 26
            (hexadecimal)          89 48 41 56 69 0d 0a 1a
            (ASCII C notation)     .dagger.21 1 H A V i .dagger.r .dagger.n
     .dagger.032

    Width:               4 bytes
    Height:              4 bytes
    Bit depth:           1 byte (value: 8)
    Color type:          1 byte (value: 3, index color, max 256 color)
    Compression method:  1 byte (value: 255, no compression)
    Filter method:       1 byte (value: 255, no information)
    Interlace method:    1 byte (using PNG method)