Communication Services; Overview Of Communication Services; Table 3-2 Communication Services Of The Cpus - Siemens Simatic S7-300 Technical Data Manual

Communication

3.2 Communication services

3.2 Communication services
3.2.1

Overview of communication services

Selecting the communication service
You need to decide on a communication service, based on functionality requirements. Your
choice of communication service will have no effect on:
• the functionality available,
• whether an S7 connection is required or not, and
• the time of connecting.
The user interface can vary considerably (SFC, SFB, ...), and is also determined by the
hardware used (SIMATIC CPU, PC, ...).
Overview of communication services
The table below provides an overview of communication services offered by the CPUs.
Table 3-2 Communication services of the CPUs
Communication service
PG communication
OP communication
S7 basic communication
S7 communication
Global data
communication
Routing PG functions
(only for CPUs with
DP or PN interface)
PtP communication
SNMP
(Simple Network
Management Protocol)
open communication by
means of TCP/IP
3-6
Functionality
Commissioning, test,
diagnostics
Monitor and modify
Data exchange
Data exchange in server
and client mode:
Configuration of
communication required.
Cyclic data exchange (for
example, flag bits)
for example testing,
diagnostics on other
networks also
Data exchange via serial
interface
Standard protocol for
network diagnostics and
configuration
Data exchange via
Industrial Ethernet with
TCP/IP protocol (by means
of loadable FBs)
Time at which the S7
connection is established ...
From the PG, starting when
the service is being used
via OP at POWER ON
is programmed at the blocks
(SFC parameters)
via active partner at POWER
ON.
does not require an S7
connection
from the PG, starting when the
service is being used
does not require an S7
connection
does not require an S7
connection
Does not require an S7
connection, is handled in the
user program by means of
loadable FBs
via MPI via DP via
PtP
X X –
X X –
X – –
Only in Only in –
server server
mode mode
X – –
X X –
– – X
– – –
– – –
CPU 31xC and CPU 31x, Technical data
Manual, Edition 08/2004, A5E00105475-05
via
PN
X
X
–
X
–
X
–
X
X