IBM G41/G50 manual Glossary, Ddc

Glossary

Addressability	The number of horizontal and vertical
	picture elements (pels) in the image.
	The higher the addressability, the
	more detailed the image that can be
	displayed on the screen.
	(Addressability is sometimes referred
	to as resolution).
DDC	Display Data Channel. A VESA
	Standard enabling ‘Plug and Play’.
Display Mode	The way in which the image generated
	by the computer is displayed on the
	screen. It is defined primarily by refresh
	rate and addressability.
DPMS	Display Power Management Signalling.
	A VESA Standard.
EPA	US Environmental Protection Agency,
	responsible for the ‘Energy Star’ power
	conservation program.
Horizontal	The number of horizontal lines drawn
Frequency	across the screen by an electron beam
	in one second. Measured in kHz.
Interlaced	An interlaced display mode causes the
	electron beam to refresh the screen
	image in two passes. One pass scans
	the even lines, the next pass scans the
	odd lines.
ISO	International Organisation for
	Standardisation, responsible for the
	ISO 9241 (part 3) Standard for
	Computer Systems.

Non-Interlaced	A non-interlaced display mode causes
	the electron beam to refresh the screen
	image in one pass.
NUTEK	Swedish National Board for Industrial
	and Technical Development, involved
	in producing power consumption
	guidelines.
Refresh Rate	The number of times per second the
	Frequency screen image is “repainted”.
	Measured in Hz. The higher the (non-
	interlaced) vertical frequency, the less
	the flicker.
Resolution	See Addressability.
SVGA	Super Video Graphics Array. Video
	Modes with 800 x 600 or higher
	addressability.
VESA	Video Electronics Standards
	Association, responsible for defining
	display mode, DPMS and DDC
	standards.
VGA	Video Graphics Array. Video standard
	with 640 x 480 addressability.
XGA	Extended Graphics Array. Video
	standard with 1024 x 768
	addressability.

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