Communication with the S7-300
5.3 Communication services on the MPI/DP interface (X1)
5.3.4 S7 basic communication
Properties
S7 basic communication is used to exchange data between S7 CPUs and the
communication-capable SIMATIC modules within an S7 station (acknowledged data
exchange). Data are exchanged across non-configured S7 connections. The service is
available via MPI subnet, or within the station to function modules (FM).
S7-based communication provides the functions you require for data exchange. These
functions are integrated into the CPU operating system.
You can utilize this service by means of "System function" (SFC) user interface.
Reference
Further information
• on SFCs can be found in the
Instruction list
, for more details refer to the
STEP 7 online
help
or to the
System and Standard Functions
reference manual.
• on communication can be found in the
Communication with SIMATIC
manual.
5.3.5 S7 communication
Properties
The CPUs act as servers in the S7 communication system. In this case, the connection is
always established by the communication partner. This service is available for MPI,
PROFIBUS and Industrial Ethernet subnets.
Services are performed by the operating system without an explicit user interface.
Note
S7 communication as a client can be implemented by means of CPs and loadable FBs.
Reference
Further information
• on SFCs can be found in the
Instruction list
, for more details refer to the
STEP 7 online
help
or to the
System and Standard Functions
reference manual.
• on communication can be found in the
Communication with SIMATIC
manual.
S7-300 CPU Data: CPU 315T-2 DP
Manual, 12/2005, A5E00427933-02
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