VIPA System 200V IM Series, Руководство пользователя

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Chapter 8 Ethernet coupler
Manual VIPA System 200V
8-4 HB97E - IM - Rev. 06/29
Ethernet supports the principle of random bus access: every station on the
network accesses the bus independently as and when required. These
accesses are coordinated by a CSMA/CD (Carrier Sense Multiple
Access/Collision Detection) scheme: every station "listens" on the bus
cable and receives communication messages that are addressed to it.
Stations only initiate a transmission when the line is unoccupied. In the
event that two participants should start transmitting simultaneously, they
will detect this and stop transmitting to restart after a random delay time
has expired.
The Ethernet coupler is connected with the modules via the backplane bus.
It collects their data and places this as "server" (slave) at the disposal of
the superordinated "client" (master system).
The communication happens via TCP/IP with leading ModbusTCP or
Siemens S5 header protocol.
Vice versa, the Ethernet coupler receives the data, addressed to it by IP
address and port, and transfers it to its output periphery. For project
engineering, VIPA offers the configuration tool WinNCS that allows you to
configure the Ethernet coupler online.
For test and diagnostic purposes the Ethernet slave provides a web server
that allows the read and write access to the I/O periphery as well as the
parameterization of the modules.
Protocols define rules or standards that enables different computers to
establish communication connections and exchange data as error free as
possible.
The so called ISO/OSI layer model is generally accepted for the
standardization of computer communication. The layer model is based
upon seven layers with guidelines for the deployment of hard- and
software.
Layer Function Protocol
Layer 7 Application Layer (Application) Siemens S5 Header,
ModbusTCP
Layer 6 Presentation Layer (Presentation)
Layer 5 Session Layer (Session)
Layer 4 Transport Layer (Transport) TCP
Layer 3 Network Layer (Network) IP
Layer 2 Data Link Layer (Security)
Layer 1 Physical Layer (Bit transfer)
Access control
Communication
Overview
Protocols