Hardware Reference
In-Depth Information
inonlytoreceptacleswithanalogsupport.Thisdesignfeatureensuresthatananalog-only
devicecannotbeconnectedtoadigital-onlyreceptacle, andviceversa.
Figure12.6
shows
the DVI-D connector. The pinout is the same as the DVI-I connector, except for the miss-
ing analog signals. The DVI-D connector is widely used on laptop port replicators and
docking stations that provide DVI support.
Figure 12.6
The DVI-D connector.
TheDVI-Iconnector shownin
Figure12.5
canbeconverted intoaVGAportforusewith
CRTs or with analog LCD panels via a simple adapter. Often new graphics cards pur-
chased at retail that support only DVI come with just such an adapter that allows you to
connect a traditional VGA connector from the display to the adapter.
Unfortunately, the Digital Display Working Group (DDWG) that created DVI has disban-
ded, leaving DVI frozen in time at the DVI 1.0 specification level. This means that DVI
will not be updated in the future. Although it has enjoyed tremendous popularity as the
first widely used digital display interface, the PC industry as a whole is slowly moving to
DisplayPort as the replacement for DVI. Many cards feature both DVI and DisplayPort
ports, or HDMI and DisplayPort ports.
HDMI
HDMI was designed by a group of multimedia companies (Hitachi, Panasonic, Philips,
Silicon Image, Sony, Thomson, and Toshiba) as a way to provide a single-cable connec-
tion for transporting digital video and audio signals between consumer electronics hard-
ware such as big-screen TVs, video games, DVD players, and home theater systems.
HDMI was introduced in December 2002, version 1.3a was introduced in November
2006, version 1.4 was introduced in June 2009, and version 1.4a was introduced in March
2010.
HDMI is basically a superset of DVI and uses the same TMDS (Transition Minimized
DifferentialSignaling)asdoesDVI.UnlikeDVI,however,eachcolorchannelalsocarries
multiplexed audio data. HDMI 1.2a and earlier supports a maximum data clock rate of
165MHz,sending10bitspercycle,or1.65Gbpsperchannel.Therearethreechannelsper
link, resulting in a maximum raw bandwidth of 4.95Gbps. Because the data is sent using
