Siemens SIMATIC PG 720 P Manual page 119

R
RAM
RAM (Random Access Memory) is a read/write memory in which every
memory location can be addressed individually and its contents changed.
RAM is used to store data and programs.
ROM ROM (Read Only Memory) is a memory in which every memory location
can be addressed individually. The stored programs and data are permanently
programmed at the factory before delivery and are not lost in the event of a
power failure.
RS-232 Interface
The RS-232 interface is a standardized interface for data transmission.
Printers, modems and other hardware modules can be connected to a RS-232
interface.
S
SCSI Interface
Small Computer System Interface. Interface for connecting SCSI devices
(hard disk drives, CD-ROM drives).
Serial Interface
Data is transmitted one bit at a time via a serial interface (port); serial
interfaces are therefore slower than parallel interfaces.
SETUP A program in which information about the device configuration (that is, the
configuration of the hardware on the programming device) is defined. The
device configuration of the programming device is preset with defaults.
Changes must therefore be entered in the SETUP if a memory extension, new
modules, or a new drive are added to the hardware configuration.
SIMATIC S5 Memory submodules for SIMATIC S5 which are programmed with the
Memory PG 720 and can be plugged into an S5 programmable logic controller.
Submodules
SIMATIC Memory
Memory submodules in credit-card format for SIMATIC S5 and SIMATIC S7
Cards
which are programmed with the PG 720 and can be plugged into an S5 or S7
programmable logic controller.
Software
The collective term for all programs which are used on a computer. The
operating system and the user programs are part of the concept "software".
STN Display Super Twist Nematic passive display
PG 720 P Programming Device
C79000-G7076-C721-02
Glossary
Glossary-9