Serial Digital Video Out (SDVO) is a proprietary
Intel
Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the developers of the x86 seri ...
technology introduced with their 9xx-series of
motherboard chipsets.
SDVO makes it possible to use a 16-lane
PCI express
PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe or PCI-e, is a high-speed serial computer expansion bus standard, designed to replace the older PCI, PCI-X and AGP bus standards. It is the common ...
slot to add additional video signalling interfaces such as
VGA
Video Graphics Array (VGA) is a video display controller and accompanying de facto graphics standard, first introduced with the IBM PS/2 line of computers in 1987, which became ubiquitous in the PC industry within three years. The term can no ...
and
DVI
Digital Visual Interface (DVI) is a video display interface developed by the Digital Display Working Group (DDWG). The digital interface is used to connect a video source, such as a video display controller, to a display device, such as a comp ...
monitor outputs,
SDTV
Standard-definition television (SDTV, SD, often shortened to standard definition) is a television system which uses a resolution that is not considered to be either high or enhanced definition. "Standard" refers to it being the prevailing sp ...
and
HDTV
High-definition television (HD or HDTV) describes a television system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since 1936; in more recent times, it refers to the g ...
television outputs, or TV tuner inputs to a system board containing an integrated Intel 9xx-series graphics processor.
SDVO adaptor cards are variously designated as ADD2 (advanced digital display, second generation) or the more
feature-rich
In software, the term feature has several definitions. The Institute of Electrical and Electronics Engineers defines the term ''feature'' in IEEE 829 as " distinguishing characteristic of a software item (e.g., performance, portability, or functio ...
MEC (media expansion card). MEC is sometimes designated as ADD2+ in Intel documents.
Intel often refers to SDVO as Serial DVO to distinguish it from other forms of
digital video out associated with prior product generations, such as the
AGP implementation of DVO and older AGP-style ADD expansion cards which are not SDVO compatible.
Proprietary status
Intel's non-standard extension of the PCI express interface is subject to a patent application ''Mapping SDVO functions from PCI express interface''
United States Application 20050172037 filed on 12 December 2003.
According to the Intel patent application, the PCI Express standard lacks a "mechanism to make use of a digital display codec using the PCI Express connector." This limitation is attributed to PCI Express defining only a fixed-frequency interface with significant packet encoding overheads, whereas "digital displays need to have variable clocking and transfer rates and need very little overhead for the transfer of video data".
The patent relates a "presence detect" mechanism to detect SDVO-type expansion cards and enable a pin-remapping of the PCI Express socket to convey SDVO signals.
As of January 2007, Intel has not publicly documented an intent to promote SDVO as an industry standard, despite its potential applicability to any PCI express platform with an
Integrated Graphics Processor
A graphics processing unit (GPU) is a specialized electronic circuit designed to manipulate and alter memory to accelerate the creation of images in a frame buffer intended for output to a display device. GPUs are used in embedded systems, mobil ...
(IGP), or the desirability from the consumer perspective that SDVO adaptor cards be compatible and freely interchangeable among all such systems.
Instead, Intel is actively promoting the development of SDVO drivers across the broad range of operating systems which run on the Intel 9xx platform. In particular, Intel has established the websit
intellinuxgraphics.orgto promote fully
open source
Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use the source code, design documents, or content of the product. The open-source model is a decentralized sof ...
d drivers supporting all video technologies embodied in their 9xx-series platform.
The upshot is that SDVO cards are compatible with a narrow range of Intel-only hardware platforms, but a broad range of software environments within that platform.
Applications
SDVO encoders can be integrated into the motherboard or placed on a
PCI express
PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe or PCI-e, is a high-speed serial computer expansion bus standard, designed to replace the older PCI, PCI-X and AGP bus standards. It is the common ...
card, allowing video connectors to be added or exchanged at low cost. SDVO adaptor cards can be designed for the following purposes (from Intel ADD2 quoted verbatim):
* Dual DVI: dual independent DVI displays
*
TV-out
The term TV-out is commonly used to label the connector of equipment providing an analog video signal acceptable for a television AV input. TV-out is different from AV-out in that it only provides video, no audio.
Types of signals and their re ...
(Composite): primary or secondary TV-out display (standard definition in PAL or NTSC formats)
* HDTV-Out: primary or secondary HDTV display
* VGA-Out: drive second RGB independent display
* DVI: primary or secondary DVI display
*
LVDS
Low-voltage differential signaling (LVDS), also known as TIA/EIA-644, is a technical standard that specifies electrical characteristics of a differential, serial signaling standard. LVDS operates at low power and can run at very high speeds ...
: LVDS interface for integrated flat panel
ADD and MEC form factors
SDVO adaptor cards are designated as ADD (advanced digital display) or MEC (media expansion card) or the equivalent ADD2+.
Older ADD cards were
AGP-based and did not provide a standard interface, posing difficulties for driver development. The second generation ADD2 cards are PCI express and employ a standard interface. There are, however, two distinct flavours of ADD2 cards: ADD2-N (normal) and ADD2-R (reverse). "Normal cards use the first channels on the PCI-E connector while Reverse cards use the last channels." The ADD2-N cards are reported to work without fuss under Linux with Intel chipsets ranging from the 915 through to the 965.
A different source claims that ADD2-N are for
ATX
ATX (Advanced Technology eXtended) is a motherboard and power supply configuration specification developed by Intel in 1995 to improve on previous de facto standards like the AT design. It was the first major change in desktop computer enclo ...
form-factor systems while ADD2-R is for
BTX form-factor systems. However, some BTX systems require ADD2-N (e.g
HPdc5700), so you will have to consult your system documentation.
According to Reseller Advocate (RAM magazine) a Media Expansion Card (MEC) is "an x16 PCIe card with an SDVO silicon module for VGA, DVI, S-Video, composite, or component output combined with an x1 PCIe analog TV tuner" introduced as a "945G platform add-on descended from the old ADD and ADD2 cards."
The application note for the 945G describes the SDVO card interface as requiring a full x16 PCI-E slot.
Intel chipsets supporting SDVO
Intel documents SDVO as existing within the chipsets integrating an
Intel Graphics Media Accelerator (GMA 900 through 3000 families).
GMA X3000
The Intel G965 series chipsets implement th
GMA X3000graphics controller, the consumer engine of the Intel Graphics Media Accelerator 3000 family. From the Intel Desktop board DG965RY Technical Product Specification, section 1.5.1.4 "Advanced Digital Display (ADD2/ADD2+) Card Support":
The GMCH routes two multiplexed SDVO ports that are each capable of driving up to a 200 MHz pixel clock to the PCI Express x16 connector. The SDVO ports can be paired for a dual channel configuration to support up to a 400 MHz pixel clock. When an ADD2/ADD2+ card is detected, the Intel GMA X3000 graphics controller is enabled and the PCI Express x16 connector is configured for SDVO mode. SDVO mode enables the SDVO ports to be accessed by the ADD2/ADD2+ card. An ADD2/ADD2+ card can either be configured to support simultaneous display with the primary VGA display or can be configured to support dual independent display as an extended desktop configuration with different color depths and resolutions.
This chipset allows the ADD2/MEC design to support TV-out (
composite video
Composite video is an analog video signal format that carries standard-definition video (typically at 525 lines or 625 lines) as a single channel. Video information is encoded on one channel, unlike the higher-quality S-Video (two channels) a ...
),
TMDS
Transition-minimized differential signaling (TMDS), a technology for transmitting high-speed serial data, is used by the DVI and HDMI video interfaces, as well as by other digital communication interfaces.
The transmitter incorporates an advan ...
for DVI 1.0,
LVDS
Low-voltage differential signaling (LVDS), also known as TIA/EIA-644, is a technical standard that specifies electrical characteristics of a differential, serial signaling standard. LVDS operates at low power and can run at very high speeds ...
, single device operating in dual-channel mode,
VGA
Video Graphics Array (VGA) is a video display controller and accompanying de facto graphics standard, first introduced with the IBM PS/2 line of computers in 1987, which became ubiquitous in the PC industry within three years. The term can no ...
output,
HDTV
High-definition television (HD or HDTV) describes a television system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since 1936; in more recent times, it refers to the g ...
output,
HDMI
High-Definition Multimedia Interface (HDMI) is a proprietary audio/video interface for transmitting uncompressed video data and compressed or uncompressed digital audio data from an HDMI-compliant source device, such as a display controller, ...
/
UDI Udi may refer to:
Places
* Udi, Enugu, a local government areas and city in Nigeria
* Udi, a place in the Etawah district of Uttar Pradesh, India
People
* Udi Gal (born 1979), Israeli Olympic sailor
* Udi Vaks (born 1979), Israeli Olympic judoka
...
support (when used with the HD Audio Link).
References
Intel Embedded Graphics Drivers FAQIntel Desktop Board DG965RY Technical Product Specificationadaptor card
€”documents devices supported
ADD2-N and ADD2-R explainedby Linux kernel developer
External links
* Inte
application notethat accompanied the Intel 945G chipset introduction
* Silicon Image offers a
SiI1364 / SiI1362chipset aimed at board designers who wish to implement SDVO products
* Chrontel also provides som
chip levelSDVO solutions
* Conexant provides chip level solutions fo
video encoding* IE
SDVO interface VGA/DVI graphics card
* x.org ADD2/ SDVO card note
{{DEFAULTSORT:Sdvo
Intel products