Siemens SIMATIC 6ES7158-3MU10-0XA0 Hardware Installation And Operating Manual page 14

Figure 2-2 Coupling of two PROFINET IO subnets with one PN/MF Coupler
Principle of operation
• Data exchange with I/O modules:
Through the configured inputs of a slot, the local CPU or EtherNet/IP scanner reads the
values that the CPU of the other subnet writes over the configured outputs of the coupling
partner.
Through the configured outputs of a slot, the local CPU or EtherNet/IP scanner writes
values that the CPU of the other subnet receives over the configured inputs of the
coupling partner.
See also
Assignment of the modules (Page 40)
PN/MF Coupler
Hardware Installation and Operating Manual, 07/2020, A5E50018670-AA
Product overview
2.1 Area of application and function
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