Configuring Hardware and Communication Connections STEP 7.pdf

Configuring the Distributed I/O (DP)
3.4.4 Configuration with Two DP Master Systems (Direct Data
Exchange: Slave > I Slave)
Several DP master systems on one physical PROFIBUS-DP subnet are also called
a multiple master system. In this configuration, input data from DP slaves can be
read very rapidly by intelligent DP slaves on the same physical PROFIBUS-DP
subnet. The intelligent DP slaves can be located on the same DP master system or
on another system.
In this manner, an intelligent DP slave such as a CPU 315-2DP can allow input
data from DP slaves to be transmitted directly to its input data area, even from
different DP master systems (that is, multiple master systems).
In principle, all DP slaves (as of a certain release) can provide selected input data
for direct data exchange (DX) between DP slaves. These input data can in turn be
used further only by intelligent DP slaves such as CPU 315-2DP.
Configuring Hardware and Communication Connections with STEP 7
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