Deployment; Basics - Wieland ricos FLEX BC MODBUS User Manual

DEPLOYMENT

6
6.1

Basics

General data
Typical field bus systems are divided into master and slave systems. Master systems are CPs, cou-
pled to a CPU, allowing remote programming res. visualization of the according CPU as well as the
data transfer between several TCP/IP participants. Slave systems on the other hand are 'data collec-
tors' that deliver the I/O data of the connected modules to the requesting master. The Ethernet cou-
pler described in this chapter is a slave system. For the communication happens via TCP/IP, the
slave system is referred to as server and a master as client. The Wieland Ethernet coupler allows you
to connect up to 64 modules of your ricos FLEX system via Ethernet. Up to 8 clients may communi-
cate simultaneously with the Ethernet coupler.
Automatic address mapping
After startup of the Ethernet coupler the modules connected to the backplane bus are determined
and mapped to his address area. With address mapping there is an area for input and an area for
output data. Using the integrated Web server, you have access to the current mapping. Here you can
also parameterize your modules.
Communication
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 com-
munication happens via TCP/IP with leading Modbus/TCP protocol. Vice versa, the Ethernet coupler
receives the data, addressed to it by IP address and port, and transfers it to its output periphery.
Protocols
Protocols define rules or standards for communication. The so-called ISO/OSI layer model is gener-
ally 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
Layer 7
Layer 6
Layer 5
Layer 4
Layer 3
Layer 2
Layer 1
Telegram structure
Wieland Electric GmbH | BA001269 | 09/2021 (Rev. A)
Function
Application Layer (application)
Presentation Layer (presentation)
Session Layer (session)
Transport Layer (transport)
Network Layer (network)
Data Link Layer (security)
Physical Layer (bit transfer)
Deployment
Protocols
MODBUS / TCP
TCP
IP
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