NEC POWERMATE ES Series, Инструкция по обслуживанию и справочник

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12 Glossary
R
RAM
Random Access Memory. A storage device into which data is entered and from which data
is retrieved in a nonsequential manner. On the system board, RAM is semiconductor-based
memory that can be read and written to by the microprocessor or other hardware devices. In
RAM, data can be directly and randomly read or written (with any choice for the address).
It’s the storage location for data that needs to be immediately available for every application
in use on your computer.
read
To extract data from a storage device such as a diskette.
ROM
Read-Only Memory. Memory in which stored data cannot be modified by the user except
under special conditions.
reset
The process of returning a device to zero or to an initial or arbitrarily selected condition.
resolution
The degree of screen image clarity. Video display resolution is determined by the number of
pixels on the screen. Resolution is usually specified in pixels by scan lines, for example,
640 by 480. See pixels.
RS-232C
Standard interface for serial devices.
S
SEC
Single-Edge Contact. The SEC cartridge containing the Pentium processor. See Slot 1.
serial interface
An interface that communicates information one bit at a time.
serial printer
A printer with a serial interface.
SGRAM
Synchronous Graphic Random Access Memory. A type of DRAM used increasingly on
video adapters and graphics accelerators. Like SDRAM, SGRAM can synchronize itself
with the CPU bus clock at speeds of up to 100 MHz. In addition, SGRAM uses several
other techniques, such as masked writes and block writes, to increase bandwidth for
graphics-intensive functions. Unlike VRAM and WRAM, SGRAM is single-ported (it can
only be accessed by one device at a time). However, it can open two memory pages at once,
which simulates the dual-port nature of other video RAM technologies (access by two
different devices simultaneously). See VRAM and WRAM.