Siemens SIMATIC ET 200M Operating Instructions Manual page 255

Glossary
Automation system
An automation system is a → programmable logic controller that comprises at least one
→ CPU, several input and output modules, and operator control and monitoring devices.
Autonegotiation
Configuration protocol in the Fast Ethernet. Before the actual data transfer the devices on
the network agree a transfer mode that each participating device can master (100 Mbps or
10 Mbps, full-duplex or half-duplex).
Backplane bus
The backplane bus is a serial data bus that the modules use to communicate with each
other. It is also used to supply the modules with the necessary voltage. The modules are
connected through bus connectors.
Baud rate
The baud rate is the data transfer speed, indicating the number of transferred bits per
second (baud rate = bit rate).
ET 200 supports baud rates between 9.6 kBaud and 12 MBaud.
Bus
Shared data transmission path by which all nodes are connected. It has two defined ends.
With ET 200 the bus can either be a two-wire or a fiber-optic cable.
Bus node
This device can send, receive or amplify data via the bus. It can be a DP master, DP slave,
RS 485 repeater, active star coupler etc.
Bus segment
→ Segment
Changing IO devices during operation (changing partner ports)
Functionality of a PROFINET device. A PROFINET device that supports this function can
communicate during operation with changing communication partners at the same port.
ET 200M
Operating Instructions, 12/2008, EWA-4NEB780600602-08
253