Modbus II

An industrial networking system that uses token*passing peer*to*peer communications at data transfer rates of five megabits per second￿ The network medium is coaxial cable￿

modem

Modulator/demodulator￿ A device that conditions digital data for transmission along an analog signal path, or conditions input signals received from the path for use as digital data￿

network

The interconnection of devices sharing a common data path and protocol for communication￿ On Modbus Plus, the devices share in the passing of a common token frame to gain sequential access for sending messages￿

Network Option Module

A hardware module that is mounted into a common backplane together with a Programmable Controller, communicating with the controller over the backplane￿ The module connects to the Modbus Plus network and provides the central point for communication between the controller's application program and the node devices on the network￿

node

A device that has a direct point of access to a communications network￿ On Modbus Plus, any device that is physically connected to the network￿

OSI Model

Open Systems Interconnection Model￿ A reference standard describing the required performance of devices for data communication￿ Produced by the International Standards Organization￿

Peer Cop

A method of peer*to*peer communication between networked devices in which data is transferred as part of the passing of tokens between nodes￿ Each node passes the token in the network's address sequence, and can be configured to transmit data in addition to the token￿ All nodes monitor the token passes, and can be configured to extract data from them￿ Nodes are setup for Peer Cop transfers as part of their initial configuration, and continue using Peer Cop as long as they are active on the network￿ Four kinds of Peer Cop communication can be transacted during each token pass: see Glo￿￿l Input￿ Glo￿￿l Output￿ Specific Input￿ and Specific Output￿

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Glossary

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Schneider Electric BM85 manual Modem, Network Option Module, Node, OSI Model, Peer Cop