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Siemens SIMATIC PANEL PC 877 User Manual

Page 276

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Glossary

SIMATIC Panel PC 877

Glossary-6

Operating instructions, Release 07/2006, A5E00877780-01

Operating system

Summarizing term describing all functions for program execution, allocation of system

resources to the various user programs, and for controlling and monitoring consistency of the

operating mode in cooperation with the hardware (e.g. Windows XP Professional).

Packet writing

The CD-RW is used as a diskette medium. The CD can then be read only by packet–writing

compatible software or has to be finalized. Finalization of a CD closes the CD within an

ISO9660 shell. You can still write to the CD-RW several times in spite of finalization. Not all

CD drives can read packet-written CDs . There are restrictions to using this method in

general data transfer.

PATA

An interface for hard disk drives and optical drives with parallel data transfer of up to 100

Mbps.

PC card

Trademark of the Personal Computer Memory Card International Association (PCMCIA).

Designation for auxiliary cards that conform with PCMCIA specifications. A PC card that has

roughly the size of a credit card can be plugged into a PCMCIA slot. Version 1 specifies

cards of Type I with a thickness of 3.3 millimeters, which is conceived mainly for use as

external memory. Version 2 of the PCMCIA specification also defines a card Type II with a

thickness of 5 mm and a card of the Type III with a thickness of 10.5 mm. Type II cards can

realize devices such as modems, fax and network interface cards. Type III cards are

equipped with devices that require more space, for example wireless communication

modules or rotary storage media (hard disks, for example).

PC/104 / PC/104-Plus

Two bus architectures are especially fashionable today in the industrial world. PC/104 and

PC/104-

Plus. Both are standard in single-board computers of the PC class. The electrical

and logical layout of the two bus systems is identical with ISA (PC/104) and PCI (PC/104-

Plus). Software cannot usually detect a difference between them and normal desktop bus

systems. Their advantage is the compact design and the resulting space they save.

PCMCIA

Association consisting of approx. 450 member companies of the computer industry. Their

focus is set on providing worldwide standards for miniaturization and flexible use of PC

expansion cards, and thus to provide a basic technology to the market.

Pentium M

Intel processor type: The architecture of the processor is designed for mobile computing; the

processor features superior performance characteristics for computer applications and

enhanced power-saving functions