Properties and functions
1.2 Further functions
Timeofday synchronization over Industrial Ethernet using the NTP mode (NTP: Network Time
The CM sends timeofday queries at regular intervals to an NTP server and synchronizes its
local time of day.
The time is also be forwarded automatically to the CPU modules in the S7 station allowing
the time to be synchronized in the entire S7 station.
Media redundancy (MRP)
Within an Ethernet network with a ring topology, the CM supports the media redundancy
protocol MRP. You can assign the role of "Client" or "Manager (Auto)" to the CM.
Addressable with the factoryset MAC address
To assign the IP address to a new CM (direct from the factory), it can be accessed using the
preset MAC address on the interface being used. Online address assignment is made in
The CM supports data queries using SNMP in version V1 (Simple Network Management
For details, see section SNMP (Page 37).
IP configuration - IPv4
The essential features of IP configuration for the CM:
● The CM supports the use of IP addresses according to IPv4.
● You can configure how and with which method the CM is assigned the IP address, the
subnet mask and the address of a gateway.
● The IP configuration and the connection configuration (IPv4) can also be assigned to the
CM by the user program (for program blocks refer to the section Programming
Note: Does not apply to S7 connections.
The CM supports static IP routing (IPv4) to other CM 1542-1 V2.0 / CP 1543-1 V2.0 in an
For details, see section IP routing (Page 31).
Operating Instructions, 07/2019, C79000-G8976-C355-04