User`s manual

Glossary
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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.