beautypg.com

Motorola MVME2400 User Manual

Page 166

background image

Glossary

GL-12

Computer Group Literature Center Web Site

G

L

O

S
S

A
R

Y

UV

UltraViolet

UVGA

Ultra Video Graphics Array. An improved VGA monitor standard
that provides at least 256 simultaneous colors and a screen
resolution of 1024 x 768 pixels.

Vertical Blanking Interval (VBI)

The time it takes the beam to fly back to the top of the screen in order
to retrace the opposite field (odd or even). VBI is in the order of 20
TV lines. Teletext information is transmitted over 4 of these lines
(lines 14-17).

VESA (bus)

Video Electronics Standards Association (or VL bus). An internal
interconnect standard for transferring video information to a
computer display system.

VGA

Video Graphics Array (IBM). The third and most common monitor
standard used today. It provides up to 256 simultaneous colors and
a screen resolution of 640 x 480 pixels.

virtual address

A binary address issued by a CPU that indirectly refers to the
location of information in primary memory, such as main memory.
When data is copied from disk to main memory, the physical address
is changed to the virtual address.

VL bus

See VESA Local bus (VL bus).

VMEchip2

MCG second generation VMEbus interface ASIC (Motorola)

VME2PCI

MCG ASIC that interfaces between the PCI bus and the VMEchip2
device.

volatile memory

A memory in which the data content is lost when the power supply
is disconnected.

VRAM

Video (Dynamic) Random Access Memory. Memory chips with
two ports, one used for random accesses and the other capable of
serial accesses. Once the serial port has been initialized (with a
transfer cycle), it can operate independently of the random port. This
frees the random port for CPU accesses. The result of adding the
serial port is a significantly reduced amount of interference from
screen refresh. VRAMs cost more per bit than DRAMs.

Windows NT™

The trademark representing Windows New Technology, a
computer operating system developed by the Microsoft Corporation.