Siemens SIMATIC Distributed I/O ET 200eco PN Operating Instructions Manual page 270

Process image (I/O)
The CPU transfers the values from the input and output modules to this memory area. At the
beginning of the cyclic program, the signal states of the input modules are transferred to the
process input image. At the end of the cyclic program the process image of the outputs is
transferred as a signal state to the output modules.
PROFIBUS
PROcess FIeld BUS, process- and fieldbus standard, which is defined in the standard
IEC 61158 Type 3. It specifies functional, electrical and mechanical properties for a bit-serial
fieldbus system.
PROFIBUS is available with the protocols DP (= Distributed Peripherals), FMS (= Fieldbus
Message Specification), PA (= Process Automation), or TF (= Technological Functions).
PROFIBUS International
Technical committee dedicated to the definition and development of the PROFIBUS and
PROFINET standard.
Also known as the PROFIBUS Trade Organization (PTO).
Homepage: www.profibus.com
PROFINET
Within the framework of Totally Integrated Automation (TIA), PROFINET represents a
consequent enhancement of:
• PROFIBUS DP, the established field bus, and
• Industrial Ethernet, the communication bus for the cell level.
Experience gained from both systems was and is being integrated into PROFINET.
PROFINET is an Ethernet-based automation standard of PROFIBUS International (previously
PROFIBUS Trade Organization) and defines a multi-vendor communication, automation and
engineering model. Since 2003, PROFINET has been part of IEC 61158.
See PROFIBUS International
PROFINET component
A PROFINET component encompasses the entire data of the hardware configuration, the
parameters of the modules, and the corresponding user program. The PROFINET component
is composed of:
• Technological function
The (optional) technological (software) function includes the interface to other PROFINET
components in the form of interconnectable inputs and outputs.
• Device
The device is the representation of the physical automation device or field device
including the IO devices, sensors, actuators, mechanics, and device firmware.
PROFINET Device
All PROFINET devices are equipped with at least one Industrial Ethernet port. A PROFINET
device can also have a PROFIBUS connection (master with proxy functionality).
ET 200eco PN
Operating Instructions, 06/2022, A5E01250250-AN
Glossary
271