Siemens SIMATIC S7-1500 Manual page 37

PROFINET interface X1 with 2-port switch (X1 P1 R and X1 P2 R)
The assignment corresponds to the Ethernet standard for an RJ45 plug.
● When autonegotiation is deactivated, the RJ45 socket is allocated as a switch (MDI-X).
● When autonegotiation is activated, autocrossing is in effect and the RJ45 socket is
allocated either as data terminal equipment (MDI) or a switch (MDI-X).
CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
Manual, 12/2017, A5E40882737-AA
Connecting up
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