Abbreviations
SIMATIC Rack PC 840 V2
19-4
Operating Instructions, Edition 05/2006, A5E00248055-04
Abbreviation
Term
Meaning
PI
Protective Earth
Protective conductor
PG
Programming device
PIC
Programmable Interrupt Controller
Programmable interrupt controller
POST
Power On Self Test
PXE
Preboot Execution Environment
Software for running new PCs without hard disk
data via the network
RAID
Redundant Array of Independent Disks
Redundant hard disk array
RAM
Random Access Memory
RI
Ring Input
Incoming call
ROM
Read-Only Memory
RS 485
Reconciliation Sublayer 485
Bi-directional bus system designed for up to
32 nodes
RTC
Real Time Clock
Real-time clock
RTS
Reliable Transfer Service
Request to send
RxD
Receive Data
Data transfer signal
SATA
Serial ATA
SCSI
Small Computer System Interface
SDRAM
Synchronous DRAM
SELV
Safety Extra Low Voltage
Safety extra low voltage
SMART
Self Monitoring Analysis and Reporting
Technology
Hard disk error diagnostics program
SMS
Short Message Service
Short message via telecommunication network
SNMP
Simple Network Management Protocol
Network protocol
SO-DIMM
Small Outline Dual Inline Memory Module
SOM
SafeCard on Motherboard (SOM)
SPP
Standard Parallel Port
Synonym for parallel port
SVGA
Super Video Graphics Array
Enhanced VGA standard with at least 256 colors
SVP
Serial number of the device
SW
Software
TCO
Total Cost of Ownership
TFT
Thin-Film-Transistor
Type of LCD flat-screen
TTY
Tele Type
Asynchronous data transfer
TxD
Transmit Data
Data transfer signal
TWD
Watchdog Time
Watchdog monitoring time
UL
Underwriters Laboratories Inc.
US organisation for tests and certifications
according to own or binational standards
(with CSA / Canada) standards
UMA
Unified Memory Architecture
URL
Uniform Resource Locator
Designation of the full address of an Internet
page
USB
Universal Serial Bus
UXGA
Ultra Extended Graphics Array
Graphic standard, maximum resolution
1.600 x 1.200 pixels