Siemens SIMATIC ET 200pro Operating Instructions Manual page 28

Pin assignment of the M12 connector
M12 circular sockets X1 P1 R and X1 P2 R:
● If autonegotiation is activated, then the M12 circular socket has the switch assignment
(MDI-X).
● If autonegotiation is activated, then autocrossing is active and the M12 circular socket has
either a device assignment (MDI) or switch assignment (MDI-X).
CPU 1516pro-2 PN (6ES7516-2PN00-0AB0)
Operating Instructions, 11/2019, A5E35873416-AC
4.3 Connecting the connection module CM CPU 2PN M12 7/8"
Mounting and connecting
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