Siemens SIMATIC Rack PC 840 Manual page 47

Connecting
Via the MPI/DP port, you can connect your PC to
S MPI networks (S7-200, S7-300, and S7-400) or
S PROFIBUS DP networks (DP components).
PROFIBUS/MPI Network
Up to 32 devices (PC, programming device, or programmable controller) can be
connected to the PROFIBUS/MPI port to form a network segment. The physical
connection to the network is via a floating RS485 port which is a component of the
PC motherboard.
Several network segments can be connected via repeaters. The complete network
can comprise up to 127 stations. Data transmission rates from 9.6 Kbps to 12
Mbps are possible.
SIMATIC Rack PC 840 Manual
A5E00104826-03
Setting Up and Operating the SIMATIC Rack PC 840
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