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24-562: The EDID data structure includes manufacturer name and serial number, product type, phosphor or filter type (as chromaticity data), timings supported by the display, display size, luminance data and (for digital displays only) pixel mapping data. DisplayID is a VESA standard targeted to replace EDID and E-EDID extensions with a uniform format suited for both PC monitor and consumer electronics devices. EDID structure (base block) versions range from v1.0 to v1.4; all these define upwards-compatible 128- byte structures. Version 2.0 defined

48-443: A l   p i x e l s = ⌊ V e r t i c a l   l i n e s ∗ A s p e c t   r a t i o / 8 ⌋ ∗ 8 {\displaystyle {\mathsf {Horizontal\ pixels}}=\lfloor {\mathsf {Vertical\ lines}}*{\mathsf {Aspect\ ratio}}/8\rfloor *8} The CTA EDID Extension

72-470: A new 256-byte structure but it has been deprecated and replaced by E-EDID which supports multiple extension blocks. HDMI versions 1.0–1.3c use E-EDID v1.3. Before Display Data Channel (DDC) and EDID were defined, there was no standard way for a graphics card to know what kind of display device it was connected to. Some VGA connectors in personal computers provided a basic form of identification by connecting one, two or three pins to ground, but this coding

96-634: A new Product ID Data Block, to replace the Manufacturer PNP ID in the first block of the EDID, since the UEFI is phasing out assigning new PNP IDs. Version 1 of the extension block (as defined in CEA−861) allowed the specification of video timings only through the use of 18-byte Detailed Timing Descriptors (DTD) (as detailed in EDID 1.3 data format above). DTD timings are listed in order of preference in

120-514: A new formula to calculate Video Timing Formats, OVT. Other changes include a new annex to elaborate on the audio speaker room configuration system that was introduced with the 861.2 amendment, and some general clarifications and formatting cleanup. An amendment to CTA-861-I, CTA-861.7, was published in June 2024. It contains updates to CTA 3D Audio, and clarifications on Content Type Indication, and on 4:2:0 support for VTDBs and VFDBs. It also introduces

144-792: Is "don't care"; 01 0 = field sequential, right during stereo sync; 10 0 = field sequential, left during stereo sync; 01 1 = 2-way interleaved, right image on even lines; 10 1 = 2-way interleaved, left image on even lines; 11 0 = 4-way interleaved; 11 1 = side-by-side interleaved. 0 = analog composite; 1 = bipolar analog composite. 0 = without serrations; 1 = with serrations (H-sync during V-sync). 0 = sync on green signal only; 1 = sync on all three (RGB) video signals. 0 = without serration; 1 = with serration (H-sync during V-sync). 0 = negative; 1 = positive. 0 = negative; 1 = positive. 0 = negative; 1 = positive. When used for another descriptor,

168-708: Is set), parameters as follows. 000 = 4∶3 001 = 16∶9 010 = 16∶10 011 = 5∶4 100 = 15∶9 00 = 4∶3 01 = 16∶9 10 = 16∶10 11 = 15∶9 00 : 50 Hz 01 : 60 Hz 10 : 75 Hz 11 : 85 Hz V e r t i c a l   l i n e s = ( A d d r e s s a b l e   l i n e s   p e r   f i e l d + 1 ) ∗ 2 {\displaystyle {\mathsf {Vertical\ lines}}=({\mathsf {Addressable\ lines\ per\ field}}+1)*2} H o r i z o n t

192-609: The CEA EDID Timing Extension. Version 2 (as defined in 861-A) added the capability to designate a number of DTDs as "native" (i.e., matching the resolution of the display) and also included some "basic discovery" functionality for whether the display device contains support for "basic audio", YC B C R pixel formats, and underscan. Version 3 (from the 861-B spec onward) allows two different ways to specify digital video timing formats: As in Version 1 & 2 by

216-473: The DTDs were read, the drivers are/were still often limited by the standard timing descriptor limitation that the horizontal/vertical resolutions must be evenly divisible by 8. This means that many graphics cards cannot express the native resolutions of the most common widescreen flat-panel displays and liquid-crystal display TVs . The number of vertical pixels is calculated from the horizontal resolution and

240-574: The Dual GTF curve concept and partially changed the encoding of aspect ratio within the standard timings. With the use of extensions, E-EDID structure can be extended up to 32 KiB, because the E-DDC added the capability to address multiple (up to 128) 256 byte segments. Some graphics card drivers have historically coped poorly with the EDID, using only its standard timing descriptors rather than its Detailed Timing Descriptors (DTDs). Even in cases where

264-689: The EDID information, such as read-edid for Linux and DOS, PowerStrip for Microsoft Windows and the X.Org Server for Linux and BSD unix . Mac OS X natively reads EDID information and programs such as SwitchResX or DisplayConfigX can display the information as well as use it to define custom resolutions. E-EDID was introduced at the same time as E-DDC , which supports multiple extensions blocks and deprecated EDID version 2.0 structure (it can be incorporated in E-EDID as an optional extension block). Data fields for preferred timing, range limits, and monitor name are required in E-EDID. E-EDID also adds support for

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288-480: The Tag code is 7, an Extended Tag Code is present in the first payload byte of the data block, and the second payload byte represents the first payload byte of the extended data block. Once one data block has ended, the next byte is assumed to be the beginning of the next data block. This is the case until the byte (designated in byte 2, above) where the DTDs are known to begin. As noted, several data blocks are defined by

312-754: The audio segments), 861-E in March 2008, 861-F, which was published on June 4, 2013, 861-H in December 2020, and, most recently, 861-I, which was published in February 2023. Coinciding with the publication of CEA-861-F in 2013, Brian Markwalter, senior vice president, research and standards, stated: "The new edition includes a number of noteworthy enhancements, including support for several new Ultra HD and widescreen video formats and additional colorimetry schemes.” Version CTA-861-G, originally published in November 2016,

336-473: The display and the graphics card; VGA , DVI , DisplayPort and HDMI are supported. The EDID is often stored in the monitor in the firmware chip called serial EEPROM (electrically erasable programmable read-only memory) and is accessible via the I²C-bus at address 0x50 . The EDID PROM can often be read by the host PC even if the display itself is turned off. Many software packages can read and display

360-571: The extension. The Video Data Blocks will contain one or more 1-byte Short Video Descriptors (SVDs). Phosphor Too Many Requests If you report this error to the Wikimedia System Administrators, please include the details below. Request from 172.68.168.236 via cp1112 cp1112, Varnish XID 944792075 Upstream caches: cp1112 int Error: 429, Too Many Requests at Thu, 28 Nov 2024 08:36:11 GMT Pixel perfect Too Many Requests If you report this error to

384-529: The pixel clock and some other bytes are set to 0: Currently defined descriptor types are: 00 = none; 10 = +255 kHz for max. rate; 11 = +255 kHz for max. and min. rates. 00 = none; 10 = +255 Hz for max. rate; 11 = +255 Hz for max. and min. rates. 00 = Default GTF (when basic display parameters byte 24, bit 0 is set). 01 = No timing information. 02 = Secondary GTF supported, parameters as follows. 04 = CVT (when basic display parameters byte 24, bit 0

408-478: The selected aspect ratio . To be fully expressible, the size of widescreen display must thus be a multiple of 16×9 pixels. For 1366×768 pixel Wide XGA panels the nearest resolution expressible in the EDID standard timing descriptor syntax is 1360×765 pixels, typically leading to 3-pixel-thin black bars. Specifying 1368 pixels as the screen width would yield an unnatural screen height of 769.5 pixels. Many Wide XGA panels do not advertise their native resolution in

432-462: The speaker configuration of the display device, and Vendor Specific Data Blocks which can contain information specific to a given vendor's use. Subsequent versions of CTA-861 defined additional data blocks. The Data Block Collection contains one or more data blocks detailing video, audio, and speaker placement information about the display. The blocks can be placed in any order, and the initial byte of each block defines both its type and its length: If

456-1077: The standard timing descriptors from EDID data. Even this is not always possible, as some vendors' graphics drivers (notably those of Intel ) require specific registry hacks to implement custom resolutions, which can make it very difficult to use the screen's native resolution. 000 = undefined 001 = 6 010 = 8 011 = 10 100 = 12 101 = 14 110 = 16 bits per color 111 = reserved 0000 = undefined 0001 = DVI 0010 = HDMIa 0011 = HDMIb 0100 = MDDI 0101 = DisplayPort 00 = +0.7/−0.3 V 01 = +0.714/−0.286 V 10 = +1.0/−0.4 V 11 = +0.7/0 V (EVC) 00 = RGB 4:4:4 01 = RGB 4:4:4 + YCrCb 4:4:4 10 = RGB 4:4:4 + YCrCb 4:2:2 11 = RGB 4:4:4 + YCrCb 4:4:4 + YCrCb 4:2:2 00 = monochrome or grayscale 01 = RGB color 10 = non-RGB color 11 = undefined 00 = 16:10 01 = 4:3 10 = 5:4 11 = 16:9 (Versions prior to 1.3 defined 00 as 1:1.) 0 = non-interlaced; 1 = interlaced. 00 x = none, bit 0

480-493: The standard timing descriptors, instead offering only a resolution of 1280×768. Some panels advertise a resolution only slightly smaller than the native, such as 1360×765. For these panels to be able to show a pixel perfect image, the EDID data must be ignored by the display driver or the driver must correctly interpret the DTD and be able to resolve resolutions whose size is not divisible by 8. Special programs are available to override

504-602: The use of 18-byte DTDs, or by the use of the Short Video Descriptor (SVD) (see below). HDMI 1.0–1.3c uses this version. Version 3 also defines a format for a collection of data blocks, which in turn can contain a number of individual descriptors. This Data Block Collection (DBC) initially had four types of Data Blocks (DBs): Video Data Blocks containing the aforementioned Short Video Descriptor (SVD), Audio Data Blocks containing Short Audio Descriptors (SAD), Speaker Allocation Data Blocks containing information about

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528-572: Was first introduced in EIA / CEA -861. The ANSI/CTA-861 industry standard, which according to CTA is now their "Most Popular Standard", has since been updated several times, most notably with the 861-B revision (published in May 2002, which added version 3 of the extension, adding Short Video Descriptors and advanced audio capability/configuration information), 861-D (published in July 2006 and containing updates to

552-445: Was made available for free in November 2017, along with updated versions -E and -F, after some necessary changes due to a trademark complaint. All CTA standards are free to everyone since May 2018. The most recent full version is CTA-861-I, published in February 2023, available for free after registration. It combines the previous version, CTA-861-H, from January 2021 with an amendment, CTA-861.6, published in February 2022 and includes

576-474: Was not standardized. This problem is solved by EDID and DDC, as it enables the display to send information to the graphics card it is connected to. The transmission of EDID information usually uses the Display Data Channel protocol, specifically DDC2B, which is based on I²C -bus (DDC1 used a different serial format which never gained popularity). The data is transmitted via the cable connecting

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