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Pipeline burst SRAM is a fast secondary cache. It is used as a secondary
cache because SRAM is slower than SDRAM, but usually larger. Data is
cached first to the faster primary cache, and then, when the primary cache is
full, to the slower secondary cache.
Pipelining improves system performance by allowing the CPU to begin
executing a second instruction before the first is completed. A pipeline can be
likened to an assembly line, with a given part of the pipeline repeatedly
executing a set part of an operation on a series of instructions.
PM timers (Power Management timers) are software timers that count
down the number of seconds or minutes until the system times out and enters
sleep, suspend, or doze mode.
PnP is an acronym for Plug and Play, a design standard that has become
ascendant in the industry. Plug and Play devices require little set-up to use.
Novice end users can simply plug them into a computer that is running on a
Plug and Play-aware operating system (such as Windows 95), and go to
work. Devices and operating systems that are not Plug and Play require you
to reconfigure your system each time you add or change any part of your
hardware.
The term RAM (Random Access Memory), while technically referring to a
type of memory where any byte can be accessed without touching the
adjacent data, is often used to refer to the systemî‚’s main memory. This
memory is available to any program running on the computer.
ROM (Read-Only Memory) is a storage chip which contains the BIOS
(Basic Input/Output System), the basic instructions required to boot the
computer and start up the operating system.
SDRAM (Synchronous Dynamic RAM) is so-called because it can keep
two sets of memory addresses open simultaneously. By transferring data
alternately from one set of addresses, and then the other, SDRAM cuts down
on the delays associated with non-synchronous RAM, which must close one
address bank before opening the next.
The serial port is so called because it transmits the eight bits of a byte of
data along one wire, and receives data on another single wire (that is, the data
GLOSSARY