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LSI U80ALVD User Manual

Page 70

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Glossary of Terms and Abbreviations

Main Memory

The part of a computer’s memory which is directly accessible by the CPU
(usually synonymous with RAM).

Mbyte

Megabyte. A measure of computer storage equal to 1024 kilobytes.

Motherboard

See Mainboard. In some countries, the term Motherboard is not
appropriate.

Multitasking

The executing of more than one command at the same time. This allows
programs to operate in parallel.

Multithreading

The simultaneous accessing of data by more than one SCSI device. This
increases the data throughput.

NVRAM

NonVolatile Random Access Memory. Actually an EEPROM
(Electronically Erasable Read Only Memory chip) used to store
configuration information. See EEPROM.

Operating
System

A program that organizes the internal activities of the computer and its
peripheral devices. An operating system performs basic tasks such as
moving data to and from devices, and managing information in memory.
It also provides the user interface.

Parity Checking

A way to verify the accuracy of data transmitted over the SCSI bus. The
parity bit in the transfer is used to make the sum of all the 1 bits either
odd or even (for odd or even parity). If the sum is not correct, the
information may be retransmitted or an error message may appear.

Passive
Termination

The electrical connection required at each end of the SCSI bus,
composed of a set of resistors. It improves the integrity of bus signals.

PCI

Peripheral Component Interconnect. A local bus specification that allows
connection of peripherals directly to computer memory. It bypasses the
slower ISA and EISA buses.

Peripheral
Devices

A piece of hardware (such as a video monitor, disk drive, printer, or
CD-ROM) used with a computer and under the computer’s control. SCSI
peripherals are controlled through a SCSI host adapter.

Pin-1
Orientation

The alignment of pin 1 on a SCSI cable connector and the pin-1 position
on the SCSI connector into which it is inserted. External SCSI cables are
always keyed to insure proper alignment, but internal SCSI ribbon cables
sometimes are not keyed.