Device Types - Omron PRT1-COM Operation Manual

Device types

1-3

Device types

Master devices
DPM1, DPM2
Slave devices
4
PROFIBUS-DP distinguishes between master devices and slave devices.
Master devices control the data communication on the bus. PROFIBUS-DP
allows more then one master in the network. A master can send messages
without an external request, as long as it holds the bus access right (the token).
Masters are also called active stations in the PROFIBUS-DP standard.
There are two types of master devices: DP master class 1 (DPM1) and DP
master class 2 (DPM2).
A DPM1 is a central controller, which exchanges information with the
decentralised stations (i.e. DP slaves) within a specified message cycle.
DPM2 devices are programmers, configuration devices or operator panels.
They are used during commissioning for configuration of the DP system or for
operation and monitoring purposes.
Slave devices are peripheral devices. Typical slave devices include input/output
devices, valves, drives and measuring transmitters. They do not have bus
access rights and they can only acknowledge received messages or send
messages to the master when requested to do so. Slaves are also called
passive stations.
The PRT1-COM is a modular slave device.
Section 1-3