6 modbus/tcp, 1 system requirements, 2 modbus/tcp - basics – Pilz PNOZ m B0 User Manual
Page 45: Section 6, Modbus/tcp, System requirements, Modbus/tcp basics, The communication module pnoz m es eth supports, 6modbus/tcp, 2 modbus/tcp basics
Modbus/TCP
Operating Manual PNOZmulti 2 Communication Interfaces
1002971EN02
45
6
Modbus/TCP
6.1
System requirements
}
PNOZmulti Configurator: from Version 9.0.0
}
PNOZ m B0 + PNOZ m ES ETH
Please contact Pilz if you have an older version.
6.2
Modbus/TCP Basics
Modbus/TCP is an open fieldbus standard published by the User Group MODBUSIDA (see
www.ModbusIDA.org).
Application Layer
Protocol
Modbus/TCP
TCP
(RFC 793)
IP
(RFC 791)
Industrial Ethernet
Physical Layer
Ethernet
Modbus/TCP is a protocol based on Industrial Ethernet (TCP/IP over Ethernet). It is one of
the protocols with Client/Server communication. Data is transferred via a request/response
mechanism using function codes (FC).
Modbus/TCP is connectionoriented, i.e. before usable data is transferred via Modbus/TCP,
a connection must first be established between two Modbus/TCP interfaces. The initiator of
the connection is called the Client. The communications partner with which the Client es
tablishes the connection is called the Server. Whether a connection on a device assumes
the role of Client or Server is defined when a connection is configured. As a result, the
Server/Client role only applies for that specific connection.