Display system for an array of video displays

A display system for connecting a computer to a display having EDID information. The display system includes a graphics card and an adapter. The graphics card is in communication with the computer and includes: a graphics processor; a graphics card controller coupled to the graphics processor; and a memory coupled to the graphics card controller and the graphics processor. The adapter has an adapter controller, the adapter coupled to the display and coupled to the graphics card, wherein the graphics card controller is configured to query the EDID information from the display and store the EDID information as emulated EDID information in the memory and further wherein the graphics processor reads the emulated EDID information from the memory rather than from the display.

BACKGROUND

Display systems comprising multiple displays in a display array are becoming more popular. These arrays typically comprise displays in displays of n by m displays, for example, 2×4, 3×3, 4×3, and 3×4 or in a single row such as 1×4 or 1×6. Large displays of 5×10 displays are not uncommon. These displays are typically driven by a computer with one or more graphic cards. Each display transmits EDID (“Extended Display Identification Data”) information to the computer, so that the operating system of the computer knows the capabilities of the display. The operating system will arrange the displays in order to display one or more “desktops” of information, for example portions of video feeds. So long as all displays remain connected and functioning, the system will generally operate as planned.

Unfortunately, when a display is disconnected or fails, the operating system will reorder the displays and the once coherent video displayed across the displays may become scrambled. When the display is replaced or cabling fixed, the operating system does not necessarily return to the same display arrangement. Thus, it is common for so called “video walls” to have scrambled video both during and after display or cable failure.

In addition, existing systems take a great deal of processing power to drive these video walls. Often, this puts limitations on the number of displays that can be driven, the resolution that can be driven of each display, and/or large minimal processing power of the computers driving the systems.

DETAILED DESCRIPTION

This disclosure provides a display system and a method for EDID emulation. Extended display identification data (EDID) is a data structure provided by a digital display to describe its capabilities to a video source (e.g. graphics card or set-top box). It is what enables a modern personal computer to know what kinds of displays are connected to it and the capabilities of such displays. EDID is defined by a standard published by the Video Electronics Standards Association (VESA). The EDID may include manufacturer name and serial number, product type, phosphor or filter type, timings supported by the display, display size, luminance data and pixel mapping data.

In the display system, from a controller of a display adapter, a controller of a graphics card receives and stores an EDID of a display as an emulated EDID in an EEPROM of the graphics card. In this detailed description, the term “adapter” refers to either an external display dongle, an internal dongle, a controller card in a display, or a daughter card mounted or connected to a controller card in a display. A graphics card reads the emulated EDID in the EEPROM of the graphics card as if reading from the display. The display system enables relative positioning of the screens on multiple displays to remain the same even if one display is disconnected from the graphics card.

The controller of the graphics card updates the emulated EDID in the EEPROM of the graphics card based on model information within the emulated EDID. The controller sends the model information to an application via an interface such as a USB (“Universal Serial Bus”) interface. Typically, the USB interface will emulate one or more serial ports to allow applications on the host to access one or more of the communication channels comprising the controller of the graphics card itself as well as the EDID within the display itself, the emulated EDID, a default manufacturing EDID and a collection of typical EDIDs stored within the controller of the graphics card. The application searches a native resolution corresponding to the desired display over the Internet or over a specific database based on the model information.

Moreover, the graphics card controller modifies the emulated EDID based on the native resolution corresponding to the display. If the application finds the native resolution of the display, the application sends it back to the graphics card controller. After retrieving the native resolution, the application further cooperates with online video conversion services such as Zencoder. Zencoder, as other similar cloud based services, receives through a link or through upload a “native” video of a particular frame-rate, bit-rate, resolution, compression method and format, and then converts, scales, re-formats or re-renders the video using high computing power, into a desired format, which in this case would be a “pixel perfect” video file exactly matching the native resolution of a single screen, or the combined resolution in terms of combined numbers of horizontal and vertical pixels across a multitude of screens. Zencoder then either streams the resulting file back to the computer for streaming display, by providing a link to a file on a storage service or allows the resulting file to be directly downloaded to the PC where the file later can be used by a combination of GPUs and CPUs to output the content through a graphic sub-system. Based on our experimental results, the loading of the GPU and CPU when playing a video stream or locally stored video file may decrease CPU/GPU utilization from 80% down to 20% or less for content before and after such an optimization process, a process we term “pixel nativization”.

In some embodiments, the memory can be an array of EEPROMs to store emulated EDIDs for multiple channels. In some embodiments, the memory of the graphic card for storing emulated EDID, if detected to be blank, is initialized with a default EDID by the graphics card controller at first power-up typically after the product manufacturing process in the factory. In some embodiments, in order to facilitate reset operation, a jumper or reset button may be configured or a software command may be issued to reset all of the EDIDs to reset the product to “factory default mode”.

FIG. 1is a block diagram of an exemplary display system in accordance with some embodiments. As shown inFIG. 1, a display system100is provided. The display system100includes a graphics card110, a plurality of displays160, and a plurality of display adapters140. In some embodiments, the display adapter140may be embedded in the display160. In one embodiment, the graphics card110provides six channels of video data respectively to, for example, six display adapters140. That is, the graphics card110drives, for example, six displays. The number of the displays and the display adapters may vary in different embodiments. The mechanism in all of the displays and display adapters is similar, soFIG. 1simply demonstrates one set of a display160and a display adapter140, and configurations of other sets of displays and display adapters are not repeated herein.

The system described below facilitates tremendous advantages over prior art systems. One feature that permits this is the use of memory, EDID (EEPROM)122, to store EDID information about each of the displays on the graphics card110. This is essentially emulated EDID information. Prior art systems rely solely on EDID information stored in the display160for reading by the graphics card and use by the computer. In contrast, embodiments described herein treat the EDID information stored in EDID (EEPROM)122as if it were the EDID information traditionally always read from the displays160. Thus, if a display is disconnected, malfunctioning, or missing, whereas prior art systems would act as if no display was present creating a host of problems, the embodiments described herein act as if the displays were all present and accounted for. Loss of one display, two displays, or all displays would not affect the operation and output of the computer and graphics card110.

In addition, the present system permits the computer to detect when a display is attached, detached, powered up or down, or various states of the display and to store or act upon that information. Additionally, prior art systems read only part of the EDID information from display160, but the present system permits reading all or some of the EDID information from the display160. Furthermore, the present system may have EDID information about the displays stored in EDID122and preconfigured from the factory or any place, even prior to any displays whatsoever being actually, physically connected to the system.

Also, the present system allows the emulated EDID information in EDID122to be modified from the actual EDID information that is actually read from the display160. For example, a display of native resolution of 1920×1080 may have EDID information noting that it may be set by the operating system at resolution that are non-native, such as 1280×720 or 800×600. The native resolution of the display is the exact number of pixels that matched the actual manufactured horizontal and vertical number of pixels in the actual LCD panel used in the display, which may be different than the reported resolution of the display according to its EDID. Such non-native resolutions will show scaling or stretching artifacts and look “fuzzy” or unclear when viewed on a display. Therefore, the present system, when storing EDID information from display160, may, by using a database to look up information about the native resolution of the display, only store as emulated EDID information on the native resolution. Thus, the ability to set non-native resolutions that look bad is eliminated. This is termed “EDID Nativization.” The use of emulated EDID stored in EDID122allows for any type of EDID information to be stored for any particular display160, regardless of the actual EDID information stored in the display160.

The graphics card110is plugged onto a motherboard (not shown) of a PC via, for example, a PCI Express Interface111. The graphics card110may include a Mobile PCI Express Module (MXM)112, a video converter114, an audio/video (“A/V”) transmitter116, a magnetic transformer118, an RJ45 connector120, a memory122, and a controller124. The Mobile PCI Express Module (MXM) is an interconnect standard for GPUs (MXM Graphics Modules) in laptops using PCI Express. Use of an MXM provides for flexibility in creating graphics cards with the appropriate level of graphics processing power. The MXM112is connected to the video converter114, for example, a Display Port to HDMI converter. The MXM112provides, for example, six channels of video data via DisplayPort interface to the video converter114. DisplayPort is a digital display interface developed by the Video Electronics Standards Association (VESA), and is primarily used to connect a video source to a computer display, though it can also be used to carry audio, USB, and other forms of data.

The output of the video converter114is connected to the audio/video transmitter116and to an EDID (EEPROM)122. The video converter114receives and outputs video data to audio/video transmitter116via HDMI interface. The audio/video transmitter116is further connected to the magnetic transformer118and transmits audio/video signal. Existing technology examples of an audio/video transmitters and receivers are: Valens chipsets utilizing HDBaseT standard and Aptovision BlueRiver chipsets using standard IP based systems. Those skilled in the art after reading this disclosure would appreciate that other chip sets with other standards could be used as the audio video transmitter116. The audio/video signal may be HDBaseT. HDBaseT is a consumer electronic and commercial connectivity standard for transmission of uncompressed high-definition video, audio, power, home networking, Ethernet, USB, and some control signals, over a common category (ordinary Cat5 may be used, but Cat6e or above provides for longer reach) cable with a standard connector (RJ45). HDBaseT can be transmitted over category 6a cables or above up to 100 meter long, with 8P8C modular connectors of the type commonly used for local area network connections. The magnetic transformer118is designed and manufactured to comply with the appropriate standard, such as HDBaseT standards.

The video data from the audio/video transmitter116is sent to a local area network130, such as Ethernet, by using the RJ45 connector120. For example, HDBaseT supports the 100 Mbit/s version of Ethernet over twisted pair known as 100BASE-T. This can provide Internet access, or enable televisions, stereos, computers and other devices to communicate with each other and access multimedia content, including video, pictures and music stored on the local network. In some embodiments, the local area network130for carrying the video data can be replaced by the Internet with proper security guidance.

The controller124is connected to the EDID (EEPROM)122and both sides of the magnetics118. The controller124may be a digital signal processor, a processor, a microprocessor, or a microcomputer on a chip. From the local area network130, the controller124receives and stores an EDID of a display160as an emulated EDID in the memory122(such as EEPROM) of the graphics card110. More details of such EDID's being transmitted to the controller124will be shown later. The MXM112reads the emulated EDID in the memory122of the graphics card110as if reading from the display160. In some embodiments, the memory122can be an array of EEPROMs to store emulated EDIDs for multiple channels. In some embodiments, the EDID122of the graphics card110for storing emulated EDID is initialized with default EDID during manufacture. In some embodiments, in order to facilitate reset operation, a jumper or switch may be configured to reset all of the EDIDs one at a time.

In the embodiment, the graphics card110sends, for example, six channels of video data and drives six display adapters, respectively. Accordingly, the controller124is configured to receive EDIDs for six channels and store them in an array of EEPROMs. In the embodiment, control signals from the controller124and video data from audio/video transmitter116are superimposed on the input of the magnetic transformer118and then sent to the display adapter140.

The display adapter140includes an RJ45 connector142, a magnetic transformer144, audio/video receiver146, and a controller148. The magnetic transformer144is designed and manufactured to comply with the appropriate standard, such as the HDBaseT standards. The audio/video receiver146receives video data from the audio/video transmitter116, by using the RJ45 connector142and the local area network130. Existing technology examples of an audio/video transmitters and receivers are: Valens chipsets utilizing HDBaseT standard and Aptovision BlueRiver chipsets using standard IP based systems. Those skilled in the art after reading this disclosure would appreciate that other chip sets with other standards could be used as the audio video receiver146.

The display160is connected to the display adapter140via HDMI interface. A memory162(such as EEPROM) storing an EDID of the display160is powered by HDMI interface even if the display is turned off. The controller148of the display adapter140may read and store the EDID of the display160in a memory149(such as EEPROM), but some embodiments do not have local storage of the EDID in a memory149. The controller148may be a digital signal processor, a processor, a microprocessor, or a microcomputer on a chip. The controller148of the display adapter140communicates with controller124of graphics card110to facilitate the transfer of EDID information between the display162and the graphics card110. In alternative embodiments, the EDID of the display is read directly by the graphics card without the need for a controller148.

Operation of the system is described in the description ofFIG. 5below. In summary, the graphics card110operates in conjunction with the adapter140to retrieve EDID information from the display160, store the EDID information in EEPROM122, and use this emulated EDID information in operation of the display. The emulated EDID information in EEPROM122may be altered such that non-native resolutions of the display160are removed. Furthermore, upon initial power-up of a system containing graphics card110, dummy EDID information will be stored in emulated EDID EEPROM122, even with no display connected to the system. Upon a Hot Plug Detect (HPD) high signal, the actual display information is fetched and replaces the dummy EDID information in EEPROM122. If the display160becomes disconnected from the graphics card110, the system continues to operate as if the display160was connected, because the system uses the emulated EDID information in EEPROM122, rather than the actual EDID information in a display. This system facilitates consistent placement of displays relative to each other, as will be described in the following paragraphs.

FIGS. 2A-2Care block diagrams of a conventional display system without emulation mechanism in accordance with some embodiments. As shown inFIG. 2A, a display array200with six displays211-216are all connected to one graphics card (not shown). The display211-216are configured to show characters “A”, “B”, “C”, “D”, “E”, and “F”.

If the display215is disconnected from the graphics card (not shown), as shownFIG. 2B, the displays211-214and216no longer show the same characters, but shows “B”, “D”, “C”, “A”, and “F”. It is because the graphics card scans the displays211-214and216if the configurations between at least one of the displays and the graphics card changes. And the graphics card may not scan all the displays211-216in the same order, resulting in the video data to be demonstrated on the displays'211-214and216being re-arranged. After that, if the display215is reconnected to the graphics card, then the graphics card scans all of the displays211-216again. As shown inFIG. 2C, the displays211-216shows “D”, “B”, “F”, “C”, “A”, and “E”. The scan of the graphics card results in the video data being demonstrated on the displays'211-216to be re-arranged in another manner. One can appreciate the misalignment this will cause a single video image spread across displays211-216.

FIGS. 3A-3Dare block diagrams of an exemplary display system with emulation mechanism in accordance with some embodiments. As shown inFIG. 3AandFIG. 1, a display array300with six displays311-316are all connected to one graphics card110and display adapters (not shown) respectively.

The controller124of the graphics card100reads and stores EDID information for each display311-316in EDID EEPROM122. The MXM112reads the emulated EDIDs in the memory122of the graphics card110as if reading from the displays311-316. As such, the displays311-316are configured to show characters “A”, “B”, “C”, “D”, “E”, and “F” as shown inFIG. 3A.

In the example, if the display315is disconnected from the graphics card110, the MXM112continues to read the emulated EDID of display315and continues to still see a display there (even though it is not there). Therefore, even though the display315is disconnected, all of the emulated EDIDs in the EEPROM122of the graphics card110to be read by the MXM112still remain the same. The MXM112reads the emulated EDIDs in the EEPROM122as if from the display315and outputs video data as if the display315is still connected. As such, the displays311-316are configured to show characters “A”, “B”, “C”, “D”, blank, and “F” as shown inFIG. 3B.

After that, if the display315is reconnected to the graphics card110, the graphics card110detects an HPD high event, triggering a comparison of the EDID of the display315and the emulated EDID in the EEPROM122. If they are the same, nothing happens. The MXM112reads the emulated EDIDs in the EEPROM122as if from the display315and outputs video data as that inFIG. 3A. As such, the displays311-316are configured to show characters “A”, “B”, “C”, “D”, “E”, and “F” as shown inFIG. 3C.

In some embodiments, as shown inFIG. 3D, if a new display315′ replaces the display315, then the controller124detects a new EDID other than the emulated EDID (of the display315) in the EEPROM122. At this time, the controller124stores the new EDID of the new display315′ in the EEPROM122. While the emulated EDIDs in the EEPROMs122of the graphics card110, except for that corresponding to the new display315′, remains the same. The controller124of the graphics card110updates the emulated EDID in the EEPROM122of the graphics card110with the new EDID corresponding to the new display315′. The displays311-314,315′, and316are configured to show characters “A”, “B”, “C”, “D”, “E”, and “F” as shown inFIG. 3D. Relative positioning of the characters on the displays311-314,315′, and316is the same because the MXM112reads the EEPROM addresses that stores the emulated EDID in the same manner as that inFIG. 3A.

FIG. 4is a block diagram of further details ofFIG. 1in accordance with some embodiments. As shown inFIG. 4, a graphics card110is provided. The graphics card110includes a Mobile PCI Express Module (MXM)112, a switch430, EEPROMs431-436, a communications interface435, and a controller124. The MXM112includes a GPU413providing video data to, for example, six channels.

As shown inFIG. 1, the controller110receives and stores an EDID of a display160as an emulated EDID in the memory122of the graphics card110.FIG. 4shows more details about how the controller works. Please refer toFIGS. 1 and 4. The controller124stores the EDID of the display160by using the switch430to access the EEPROMs122. The switch430communicates with the controller124via I2C Bus. I2C uses two bidirectional open-drain lines, Serial Data Line (SDA) and Serial Clock Line (SCL), pulled up with resistors. The controller has a Write Protect line in communication with EEPROMs122. The controller124further updates the emulated EDID in the EEPROMs122over SDA and SCL (441-446) based on model information (such as DELL U2415) in the emulated EDID. The controller124sends the model information (such as DELL U2415) to an application via a serial interface, such as USB interface435. The application searches for a native resolution (such as 1920×1200) corresponding to the display160over the Internet or a specific database based on the model information (example, DELL U2415). The native resolution of a LCD, LCoS or other display refers to its single fixed resolution of actual number of pixels. As an LCD display consists of a fixed raster, it cannot change physical resolution to match the signal being displayed, meaning that optimal display quality can be reached only when the signal input matches the native resolution. Moreover, the controller124modifies the emulated EDID based on the native resolution (such as 1920×1200) corresponding to the display160.

For example, if the application finds the native resolution of the display160, the application sends it back to the controller124. The controller124adds the native resolution corresponding to the display160to the emulated EDID in the EEPROM431of the graphics card110, and may remove the remaining resolutions except for the native resolution within the emulated EDID in the EEPROM431of the graphics card110.

After retrieving the native resolution, the application further cooperates with a video player (for example, online video conversion service, such as Zencoder). Zencoder takes care of video scaling which requires high computing power, and sends “pixel perfect” video stream back to the system. Pixel perfect refers to: that the number of pixels in the video source perfectly align to a native resolution of a display. Based on our experimental results, the loading of the GPU413and CPU (not shown) when playing video stream may decrease from 80% to 20% due to the pixels perfectly matching the actual resolution of the displays.

Communications interface435may be any type of communications port. For example, it may be a serial port, such as a USB port. Those skilled in the art will appreciate that any type of communications port of any protocol could be used and interfaced with graphics card controller124. Communications interface435may be in communication with, for example, the host computer in which adapter110is mounted. Thus, the host computer can communicate via communications interface435directly with the graphics card controller124. For example, applications or web browsers may open a port to communicate directly with a graphics card controller124to issue commands or requests of the graphics card controller124.

As the graphics card controller124is in communication with the adapter controller148, the host computer can effectively issue commands or requests to the display160. For example, the controllers124and148may cooperate to issue commands to the display160using the Consumer Electronics Control (“CEC”) protocol. Using CEC, the host computer can issues commands to, for example, turn displays on or off; adjust contrast or brightness; or adjust color. CEC can also be used to query information from the displays, such as the model, serial number, and manufacturing date of the display.

Those skilled in the art after reading this disclosure can understand the broad range of use that this unique ability allows. For example, a database can be established, either locally at the host computer or in the cloud, that could store information about the displays that comprise a video wall—essentially an inventory of the displays that make up a video wall along with information about each of the displays. An application or web browser would open a port to the communications interface435of the graphics card110. The application or web browser would then query each, or only a select number, of displays attached to the system; retrieve information about each of the displays; and store this information in the database. Thus, a near instant inventory of a display wall could be accomplished.

FIG. 5is a flow chart of a method for EDID emulation in accordance with some embodiments. Upon initial power-up of a system, the method may determine whether emulated EDID, typically stored in EEPROM, is blank (stage505). If not blank, the method continues at stage530described below. If the emulated EDID is blank, denoting that the system has not previously been powered-up, the method will program the EEPROM's emulated EDID with generic EDID information (stage510). This generic information may be preselected and may be, for example, EDID information for a display having a 1024×768 display. Those skilled in the art after reading this disclosure will appreciate that other values could be chosen. After writing the generic EDID information to the EEPROM, the method will check if the programming of the EEPROM was successful (stage515). If not successful and the number of attempted writes (denoted as “Count” in the figure) is less than a preset number n, for example, three, (stage520) then the system will increment Count and again attempt to program the EEPROM (stage510). If not successful and the number of attempted writes is equal to or greater than n (stage520), then the method will let a user know that a write attempt to the emulated EDID EEPROM has failed, typically by, for example, lighting or flashing an LED (stage525).

If the write of the emulated EDID was verified as correct (stage515), the method will wait to detect whether a display has been plugged in (Hot Plug Detect, HPD, going high) (stage530). If a display has been detected by HPD going high (stage530), EDID information is read from the display that has been attached (stage540). Next, a check is made to see if the header of the read EDID information matches the header of the emulated EDID stored in the EEPROM (stage540). The header of the EDID contains the model number and serial number of the attached display, thus the method can determine whether a new or different display has been attached. If the information matches, the method continues at stage585described below.

If the header information read from the display does not match the header information in the emulated EDID, a new or different display has been attached and the read EDID information is stored in the EEPROM as emulated EDID (stage550). After writing the EDID information to the EEPROM, the method will check if the programming of the EEPROM was successful (stage555). If not successful and the number of attempted writes (denoted as “Count” in the figure) is less than a preset number n, for example, three, (stage560) then the system will increment Count and again attempt to program the EEPROM (stage550). If not successful and the number of attempted writes is equal to or greater than n (stage560), then the method will let a user know that a write attempt to the emulated EDID EEPROM has failed, typically by, for example, lighting or flashing an LED (stage525).

Following a successful write of the actual EDID information from the display to the emulated EDID EEPROM, the method will determine whether a Nativization option has been activated. If not, the method continues at stage585. If Nativization has been activated (stage565), the method will look up the native resolution of the display (stage570). Native resolution of the display may be stored in a lookup table at the local system, may be located on a remote server, or may be stored in the cloud. Those skilled in the art will appreciate after reading this disclosure how databases can be created and accessed to hold, maintain, and update native display resolutions for various models of displays. Typically using the model number of the display, the native resolution of the display is retrieved from the database or lookup table (stage570).

At this point, the emulated EDID is rewritten to the EEPROM to remove non-native resolutions from the list of resolutions supported by the display (stage572). Thus, the display will be operated by the system at its native resolution, providing picture perfect quality. After writing the EDID information to the EEPROM, the method will check if the programming of the EEPROM was successful (stage575). If not successful and the number of attempted writes (denoted as “Count” in the figure) is less than a preset number n, for example, three, (stage580) then the system will increment Count and again attempt to program the EEPROM (stage572). If not successful and the number of attempted writes is equal to or greater than n (stage580), then the method will let a user know that a write attempt to the emulated EDID EEPROM has failed, typically by, for example, lighting or flashing an LED (stage525).

Following a successful write to the EEPROM, the method will wait to see if the display becomes disconnected (stage585). If not, the method waits (stage585). If it does become disconnected, the method returns to stage530to wait for a display to become plugged in.

One additional embodiment is disclosed inFIG. 6.FIG. 6is a block diagram of an exemplary display system in accordance with some embodiments. As shown inFIG. 6, a display system600is provided. The display system600includes a graphics card610, a display660, and a display adapters640. In some embodiments, the display adapter640may be embedded in the display660. In one embodiment, the graphics card610provides a single channel of video data to the display adapter640. Graphics card610may be mounted in an enclosure external to a computer system.

The system described below facilitates tremendous advantages over prior art systems. One feature that permits this is the use of memory, EDID (EEPROM)622, to store EDID information about the display660on the graphics card610. This is essentially emulated EDID information. Prior art systems rely solely on EDID information stored in the display160for reading by the graphics card and use by the computer. In contrast, embodiments described herein treat the EDID information stored in EDID (EEPROM)622as if it were the EDID information traditionally always read from the displays660. Thus, if a display is disconnected, malfunctioning, or missing, whereas prior art systems would act as if no display was present creating a host of problems, the embodiments described herein act as if the display was. Loss of the display would not affect the operation and output of the computer and graphics card110.

In addition, the present system permits the system600to detect when a display is attached, detached, powered up or down, or various states of the display and to store or act upon that information. Additionally, prior art systems read only part of the EDID information from display660, but the present system permits reading all or some of the EDID information from the display660. Furthermore, the present system may have EDID information about the displays stored in EDID122and preconfigured from the factory or any place, even prior to any display being actually, physically connected to the system600.

Also, the present system allows the emulated EDID information in EDID622to be modified from the actual EDID information that is actually read from the display660. For example, a display of native resolution of 1920×1080 may have EDID information noting that it may be set by the operating system at resolution that are non-native, such as 1280×720 or 800×600. Therefore, the present system, when storing EDID information from display660, may, by a computer in conjunction with serial port626and using a database look up information about the native resolution of the display and only store as emulated EDID information on the native resolution. Thus, the ability to set non-native resolutions that look bad is eliminated. The use of emulated EDID stored in EDID622allows for any type of EDID information to be stored for any particular display660, regardless of the actual EDID information stored in the display660.

The graphics card610is external to a computer and interfaces to a computer via a graphics connector, such as a Display Port connector612or an HDMI connector615. DisplayPort is a digital display interface developed by the Video Electronics Standards Association (VESA), and is primarily used to connect a video source to a computer display, though it can also be used to carry audio, USB, and other forms of data. The graphics card610may include a video converter614, an audio/video (“A/V”) transmitter616, a magnetic transformer618, an RJ45 connector620, a memory622, and a controller624. The Display Port connector612is connected to the video converter614, for example, a Display Port to HDMI converter.

The output of the video converter614is connected to the audio/video transmitter616and to an EDID (EEPROM)622. The video converter614outputs video data to audio/video transmitter616via HDMI interface. Furthermore, the HDMI connector is connected to audio/video transmitter616. Thus, either Display Port video from Display Port connector612or HDMI video from HDMI connector615may be transmitted. The audio/video transmitter616is further connected to the magnetic transformer618and transmits audio/video signal. Existing technology examples of an audio/video transmitters and receivers are: Valens chipsets utilizing HDBaseT standard and Aptovision BlueRiver chipsets using standard IP based systems. Those skilled in the art after reading this disclosure would appreciate that other chip sets with other standards could be used as the audio video transmitter616. The audio/video signal may be HDBaseT. HDBaseT is a consumer electronic and commercial connectivity standard for transmission of uncompressed high-definition video, audio, power, home networking, Ethernet, USB, and some control signals, over a common category (ordinary Cat5 may be used, but Cat6e or above provides for longer reach) cable with a standard connector (RJ45). HDBaseT can be transmitted over category 6a cables or above up to 100 meter long, with 8P8C modular connectors of the type commonly used for local area network connections. The magnetic transformer118is designed and manufactured to comply with the appropriate standard, such as HDBaseT standards.

The video data from the audio/video transmitter616is sent to a local area network630, such as Ethernet, by using the RJ45 connector620. For example, HDBaseT supports the 100 Mbit/s version of Ethernet over twisted pair known as 100BASE-T. This can provide Internet access, or enable televisions, stereos, computers and other devices to communicate with each other and access multimedia content, including video, pictures and music stored on the local network. In some embodiments, the local area network630for carrying the video data can be replaced by the Internet with proper security guidance.

The controller624is connected to the EDID (EEPROM)622and both sides of the magnetics618. It is also connected to serial port626. The controller624may be a digital signal processor, a processor, a microprocessor, or a microcomputer on a chip. From the local area network630, the controller624receives and stores an EDID of a display660as an emulated EDID in the memory622(such as EEPROM) of the graphics card610. A PC connected to the Display Port interface612or the HDMI interface615reads the emulated EDID in the memory622of the graphics card610as if reading from the display660. In some embodiments, the EDID622of the graphics card610for storing emulated EDID is initialized with default EDID during manufacture. In some embodiments, in order to facilitate reset operation, a jumper or switch may be configured to reset the emulated EDID.

The controller624is configured to receive EDIDs for six channels and store them in an array of EEPROMs. In the embodiment, control signals from the controller624and video data from audio/video transmitter616are superimposed on the input of the magnetic transformer618and then sent to the display adapter640.

The display adapter640includes an RJ45 connector642, a magnetic transformer644, audio/video receiver646, and a controller648. The magnetic transformer644is designed and manufactured to comply with the appropriate standard, such as the HDBaseT standards. The audio/video receiver646receives video data from the audio/video transmitter616, by using the RJ45 connector642and the local area network630. Existing technology examples of an audio/video transmitters and receivers are: Valens chipsets utilizing HDBaseT standard and Aptovision BlueRiver chipsets using standard IP based systems. Those skilled in the art after reading this disclosure would appreciate that other chip sets with other standards could be used as the audio video receiver646.

The display660is connected to the display adapter640via HDMI interface. A memory662(such as EEPROM) storing an EDID of the display160is powered by HDMI interface even if the display is turned off. The controller648of the display adapter640may read and store the EDID of the display660. The controller648may be a digital signal processor, a processor, a microprocessor, or a microcomputer on a chip. The controller648of the display adapter640communicates with controller624of graphics card610to facilitate the transfer of EDID information between the display662and the graphics card610. In alternative embodiments, the EDID of the display is read directly by the graphics card without the need for a controller648.

Operation of the system is described briefly below. In summary, the graphics card610operates in conjunction with the adapter640to retrieve EDID information from the display660, store the EDID information in EEPROM622, and use this emulated EDID information in operation of the display. The emulated EDID information in EEPROM622may be altered such that non-native resolutions of the display660are removed. Furthermore, upon initial power-up of a system containing graphics card610, dummy EDID information may be stored in emulated EDID EEPROM622, even with no display connected to the system. Upon a Hot Plug Detect (HPD) high signal, the actual display information is fetched and replaces the dummy EDID information in EEPROM622. If the display660becomes disconnected from the graphics card610, the system continues to operate as if the display660was connected, because the system uses the emulated EDID information in EEPROM622, rather than the actual EDID information in a display.