Simatic comunicaciones e

Configurations for Communication
Communication with Automation Systems
Planning - Configuring - Referencing

Rev. A - Endgültig 12.04.2004 2/185
Copyright©SiemensAG2005Allrightsreserved
20982954_SIMATIC_Comm_DOKU_v10_e
Preamble
Introduction
Nowadays, the communication possibilities between automation systems
are a core demand and necessity, even in the case of systems of the lower
performance class. Due to the large variety of communication processors,
protocols and user interfaces in the SIMATIC homogenous system world
(i.e. only SIMATIC systems communicate with each other) and particularly
in the heterogeneous system world (i.e. SIMATIC systems communicate
with “third party” automation systems) this topic is extremely complex.
Basic knowledge of the principles behind protocol mechanisms, protocols
utilizable with the bus systems, as well as their properties, are just as im-
portant as the concrete implementation of a solution approach on the basis
of proven application samples.
Specific problems with the communication tasks
From the user’s or planner’s viewpoint, the following questions may often
arise when planning the communication solutions:
1. Which Bus System is available as platform for the planned automation
solutions?
2. Which Protocol can be efficiently employed for the planned task on this
bus system and will be supported by the systems to be connected?
3. How will these Protocols be used to achieve effectively the desired
automation solution?
4. Which further mechanisms are required to solve the given task effi-
ciently?
Objective of this document
The reader is enabled to face the concrete problems within the planning
and configuration phase in two steps:
1. The main document which
prepares and clearly displays the basic information about possible bus
systems and protocols being essential for the user.
2. A collection of the applications, which are complete within themselves,
which takes up typical communication problems and offers praxis-
oriented solutions by using chosen protocols and further communication
mechanisms.
The applications are prepared in a way that, on the one hand, the problem-
oriented utilization and the embedding of the used protocols in the own
user program are shown concretely and, on the other hand, further neces-
sary program mechanisms required for solving the problems are explained.

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Addressed group of persons
This document and the attached applications as a whole provides both ba-
sic knowledge as well as example solutions. This teaching material is cre-
ated e.g. for users …
• Who want to familiarize themselves with the complex topic
“Communication for Automation Systems“ more intensely.
• Who need a bus- and protocol oriented overview of all possible
constellations within the SIMATIC
• Who need a glossary for the topic “Communication with SIMATIC“
User with these demands may be, e.g.:
• Starters of the SIMATIC communication
• Technically oriented marketing advisors who want to use this teaching
material for their presale or planning phase
• Project planners / developers, who are looking for testes modules as
basis for their own advancement.
Structure of this document
This document is divided into the 4 following parts:
Table 1-1
Part Title with brief description
1 Communication structures in the SIMATIC S7
This chapter gives you an overview of the structural design and the mechanisms of the
communication within the SIMATIC.
2 Bus-orientated selection aid of applicable protocols
This chapter is intended as selection aid and jump distributor in the protocol summary.
3 Description of the available protocols
This chapter comprises a collection of summaries trying to explain in a short and com-
parable form the individual protocols.
4 A glossary on term explanation
As a conclusion, the terms used in the main document are explained more detailed.
Using the hyperlinks
This document has been structured by means of hyperlinks to keep the
structure of the main document as linear as possible. Each subchapter
includes a return jump point to return the next higher level of the hierarchy.
The highest level will be reached as soon as chapter 2 Bus-oriented Se-
lection Aid of Usable Protocols has been reached. A hyperlink is marked
by means of a blue written and underlined text:
Back to the bus-oriented selection aid of usable protocols

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Working with this Document
There are two ways to use this document
• The pragmatic start
The user can read the document as of the first chapter and obtain
an overview of the available interfaces and the applicable protocols.
• The problem-oriented start
By means of a concrete problem, a solution for a communication
task is sought here.
The following steps are performed:
Table 1-2
Step Description
1 The start into the document is the “Bus-oriented Selection Aid
of Usable Protocols”. Here you can find an overview of the
viewed bus systems and their case constellations which can be
opened via hyperlinks.
2 On the side opened via the selected hyperlink branch, the
available detail constellation is to be carried out or the detail
constellation has already been reached.
3 Each detail constellation is represented by an overview of
approx. 4 pages. It contains:
○ An overview of the connection case on hand
○ An overview of the possible hardware constellations and
the protocol used therein
○ An overview of the properties of the usable protocols as
well as
○ An estimate of the performance of the used protocol, if
available, as well as an overview of the application
samples available for this bus or for the protocol.
4 In the protocol overview, each of the stated protocols can be
branched via hyperlinks. This opens a protocol summary outlin-
ing the protocol on a further approx. 4 pages.

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Warranty, Liability and Support
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Any claims against us - based on whatever legal reason - resulting from
the use of the examples, information, programs, engineering and perform-
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gross negligence, or injury of life, body or health, guarantee for the quality
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product, fraudulent concealment of a deficiency or breach of a condition
However, claims arising from a breach of a condition which goes to the root
of the contract shall be limited to the foreseeable damage which is intrinsic
to the contract, unless caused by intent or gross negligence or based on
mandatory liability for injury of life, body or health. The above provisions do
not imply a change in the burden of proof to your detriment.
The Configurations are not binding and do not claim to be complete regard-
ing the circuits shown, equipping and any eventuality. They do not repre-
sent customer-specific solutions. They are only intended to provide support
for typical applications. You are responsible in ensuring that the described
products are correctly used.
These Configurations do not relieve you of the responsibility in safely and
professionally using, installing, operating and servicing equipment. When
using these Configurations you recognize that Siemens cannot be made li-
able for any damage/claims beyond the liability clause described above.
We reserve the right to make changes to these Configurations at any time
without prior notice. If there are any deviations between the recommenda-
tions provided in these Configurations and other Siemens publications -
e.g. Catalogs - then the contents of the other documents has priority.
Copyright© 2004 Siemens A&D. It is not permissible to transfer or
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prior authorization from Siemens A&D in writing.
For questions about this document please use the following
e-mail-address:
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Table of Contents
1 Communication Structures in the SIMATIC............................................. 8
1.1 Internal communication structures (paths)................................................... 8
1.2 External communication structures (paths).................................................. 9
1.3 Bus systems............................................................................................... 10
1.3.1 Two-point connection................................................................................. 11
1.3.2 Multipoint connection ................................................................................. 11
1.3.3 Overview of the bus systems available in SIMATIC................................... 12
1.4 Communication display in the SIMATIC family .......................................... 13
1.4.1 The S7-200 family...................................................................................... 13
1.4.2 The S7-300/400 family............................................................................... 15
1.4.3 WinAC-Basis/RTX...................................................................................... 17
1.4.4 WinAC-Slot................................................................................................. 18
2 Bus-oriented Selection Aid of Usable Protocols .................................. 20
2.1 MPI bus...................................................................................................... 21
2.1.1 CPU connection external ........................................................................... 22
2.1.2 CPU connection internal ............................................................................ 26
2.2 PROFIBUS................................................................................................. 29
2.2.1 PB CPU – CP connection .......................................................................... 30
2.2.2 PB CP-CP connection................................................................................ 36
2.2.3 PB CPU – CPU connection........................................................................ 42
2.2.4 PC Broadcast / Multicast............................................................................ 47
2.3 Industrial Ethernet...................................................................................... 51
2.3.1 IE CPU – CP connection............................................................................ 52
2.3.2 IE CP – CP connection .............................................................................. 56
2.3.3 IE CPU – CPU connection ......................................................................... 61
2.3.4 IE Broadcast / Multicast ............................................................................. 64
2.4 Serial Interface........................................................................................... 67
2.4.1 PtP- connection.......................................................................................... 69
2.4.2 PtP Multicast / Broadcast........................................................................... 73
2.5 SIMATIC backplane bus ............................................................................ 76
2.5.1 Backplane connection................................................................................ 77
3 Protocol Description................................................................................ 81
3.1 Protocols within SIMATIC S7..................................................................... 82
3.1.1 Global data................................................................................................. 84
3.1.2 S7 basic communication (MPI, PB_DP)..................................................... 88
3.1.3 S7 communication (IE, PB, MPI)................................................................ 98
3.2 Industrial Ethernet.................................................................................... 110
3.2.1 ISO Transport protocol............................................................................. 112
3.2.2 TCP protocol ............................................................................................ 116
3.2.3 ISO on TCP protocol................................................................................ 120
3.2.4 UDP Protocol ........................................................................................... 125
3.3 PROFIBUS............................................................................................... 130

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3.3.1 FDL protocol............................................................................................. 132
3.3.2 DP protocol .............................................................................................. 140
3.3.3 FMS protocol............................................................................................ 148
3.4 Serial Protocols........................................................................................ 153
3.4.1 Protocol RK512........................................................................................ 155
3.4.2 Procedure 3964(R)................................................................................... 158
3.4.3 Free ASCII protocol.................................................................................. 160
3.4.4 Modbus protocol....................................................................................... 162
3.4.5 Data highway protocol.............................................................................. 172
4 Compendium / Glossary........................................................................ 178

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1 Communication Structures in the SIMATIC
Introduction
The following chapter deals with the basic principles and concepts of the
communication within the SIMATIC environment required for the data ex-
change within or between the automation devices.
1.1 Internal communication structures (paths)
Introduction
The automation system SIMATIC is based on a modular system of modules
of different functionalities.
To use this system in its modularity, a control mechanism is required via
which all parts of the system can communicate with each other.
Within the SIMATIC, this task is realized by means of a backplane bus.
General display of the backplane bus systems
Figure 1-1
The backplane bus system is structured as follows:

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Table 1-1
Bus system Task
Communication
bus (K-bus)
The communication bus (also K-bus) has the task to manage the acyclic
data exchange to:
• CPs
• IP / FMs and
• Other CPUs
A bus system is available here which also allows for connections
between the stations without using the CPU.
P-bus (I/O bus) The P-bus (I/O-bus) is responsible for the data exchange between CPU
and the centralized I/O.
Here, it is possible to access data or to transfer data which are stored in
the I/O area of the CPs or IP / FMs.
1.2 External communication structures (paths)
Introduction
One of the core functionalities in today’s automation world is to coordinate
different automation systems with each other. This coordination is made
via an up-to-date exchange of data between the individual systems.
To connect the systems with each other, communication paths are required
enabling even the overcoming of larger distances. These communication
paths present themselves in the form of standardized interfaces offering
services for data transfer.
General presentation of the external communication structure
Figure 1-2
The external communication structure can be divided as follows:

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Table 1-2
Interface Description
CPU-internal
interface
CPU-internal interfaces are directly at the CPU. There
they are either directly connected to the associated
internal bus (e.g. MPI) or directly connected to a proc-
essor of the CPU.
A direct connection has the advantage that:
• Restrictions by the backplane bus will be avoided
• thus providing a certain performance advance.
External
interfaces
The external communication interfaces are usually
within the station racks or in an expansion rack as a
communication module.
Some of the communication modules can also be
used in the distributed, not intelligent units.
A connection of these modules to each other or to a
CPU is either made:
• Via the communication bus
• or the I/O bus. (Decentralized I/O is also as-
signed to the I/O)
1.3 Bus systems
Introduction
The interfaces offered in the SIMATIC family are divided in their physical
types of connection into the following groups:
• Two-point connections or
• Multipoint connections.
To provide a simple distinctive possibility the main differences of both types
of connection are shown here:
Table 1-3
Two-point connection Multipoint connection
1 connection partner for each inter-
face
n connection partner for each inter-
face
Small distances bridgeable (approx.
10 – 1000 m)
Larger distances bridgeable (much
longer than 100 km)
Small protocol effort with comparable
data transmission security
High protocol effort with comparable
data transmission security
High deterministics High deterministics only via high
protocol effort

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1.3.1 Two-point connection
Two-point connection or peer-to-peer connections are direct connections be-
tween 2 end points.
Figure 1-3
Peer-to-peer connections are often designed as serial connections.
In case of serial connections, standardized interfaces like RS 232, TTY
(20mA) or RS 422/RS485 are usually used. The protocols used here are,
for example, ASCII, RK512 or the 3964 R protocol.
1.3.2 Multipoint connection
In case of multipoint connections, several stations are connected with each
other via a joint transmission medium in order to exchange data.
Figure 1-4
The multipoint connection is the classic case of a bus system. Two or more
stations use the same transmission medium. For example twisted two-wire
circuits, tri-axial cables or duplex fiber-optic cables can be used as a
transmission medium.
Bus systems can be set up as
• Bus / line structures
• Tree structures
• Star structures or
• Ring structures.

Main document e-Infoshop Communication using automation systems
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Copyright © Siemens AG 2005 All rights reserved
1.3.3 Overview of the bus systems available in SIMATIC
In the following table some of the main properties of protocols available in SIMATIC are compared with each other.
Table 1-4
Bus system Transmission Rates Number
of stations
Maximum network
size
Redundancy ability Connection technol-
ogy
Bus medium
MPI 187.5 kBit/s –
12 MBit/s
32 (126) 50 m/el. segment
otherwise see
PROFIBUS
No (with OLM: Yes) RS 485, optical fiber Shielded TP, optical
fiber
PROFIBUS 9.6 kBit/s –
12 MBit/s
126 9.6 km elect.
>90 km optical
Yes RS 485, optical fiber Shielded TP, optical
fiber
Industrial
Ethernet
10 MBit/s –
1 Gbit/s
Over 1000 2.5 km elect.
about 200 km optical
Yes AUI, 9 pin Sub D,
RJ45
Tri-axial cable,
shielded TP, optical
fiber, WiFi
ASI-Bus 167 kBits/sec 1 Master
31 / 62 Slaves
500 m with Repeater
and Extender
No ASI interface line with
penetration technique
ASI interface line
Serial PtP 300 Bit/s –
115.2 kBit/sec
Without special driver
2
V 24 : 10m
TTY : 1.000m
X 27 : 1.200m
No RS 232 C (V.24),
20 mA (TTY),
RS 422/485 (X 27)
V 24 cable, shielded
TP, TTY cable
Master/Slave 300 Bit/sec – 76.8
kBit/sec TTY up to
19.2 kBit/sec
247
max. 32 per RS 485
segment
V 24 : 10m
TTY : 1.000m
X 27 : 1.200m
No RS 232 C (V.24),
20 mA (TTY),
RS 422/485 (X 27)
TP, TTY cable
Data highway 300 Bit/sec – 76.8
kBit/sec TTY up to
19.2 kBit/sec
32 V 24 : 10m
TTY : 1.000m
X 27 : 1.200m
No RS 232 C (V.24),
20 mA (TTY),
RS 422 (X 27)
TP, TTY cable
SIMATIC
backplane
bus
187.5 kBit/s or 10.5
MBit/sec
Rack-dependent Rack size No SIMATIC backplane
bus connector
SIMATIC backplane
bus

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1.4 Communication display in the SIMATIC family
Introduction
The following chapter shows the communication possibilities of the individ-
ual controller families. In this connection, the individual system families are
described together with their communication module families.
1.4.1 The S7-200 family
The following communication possibilities are available for the S7-200 fam-
ily:
Figure 1-5

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Table 1-5
Module Description
CPU interface The following three operating modes are possible with the CPU-
owned interfaces:
• As a PPI interface with PPI protocol fo
• As an MPI interface with MPI slave functions for CPU
/ CPU communication and HMI applications
• As a freely programmable, serial interface supporting
the ASCII protocol.
The desired operating mode can be set for the CPU. Up to
two interfaces can be available for each PU.
Serial interface
(EM 241)
The only serial expansion module of the S7-200 being available
so far is the EM241. It offers a modem interface.
The application range of this module is remote diagnostics and
the PC communication or the message transmission via SMS /
pager. The module offers the PPI protocol or a Modbus slave
support.
Industrial Ethernet inter-
faces
(CP 243-1 /
CP 243-1 IT)
The Ethernet CPs 243-1 or 243-1 IT are designed for connecting
the S7-200 to the Ethernet. These allow for a direct connection of
controllers of the S7-300 / S7-400 family as well as of PCs for
programming or HMI functions.
Moreover, the IT version is able to allow for direct access to the
controller via a built-in HTTP-Server functionality or FTP func-
tions. In addition, a limited E-Mail client function enables sending
messages.
ASI master interface
(CP 243-2)
The CP 243-2 is an AS-I master of the specification 2.1. It can be
used for connecting up to 62 AS-I slaves. A direct processing of
analog values is possible
PROFIBUS interface
(EM 277)
The expansion module EM277 is used as a valuable DP slave
interface for the PROFIBUS. Programming as well as S7 Server
functions can be operated simultaneously via this module.

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1.4.2 The S7-300/400 family
The following communication possibilities are available for the S7-300 / S7-
400:
Figure 1-6
Table 1-6
Module Description
CPU interfaces Depending on the type, the CPU offers 3 different internal inter-
faces:
• MPI interface for programming functions or for HMI functions
or for a simple connection between controllers.
• PROFIBUS DP (also MPI/DP) interface for connecting de-
central field devices, HMI systems or usable as program-
ming interface.
• Industrial Ethernet / PROFInet interface for connecting PRO-
FInet networks, suitable as programming interface or as
connection of HMI systems
Serial interface
(e.g. CP 440,
CP 340 / CP 441-1,
CP 341 / CP 441-2)
There are various different serial interfaces available for the S7-300
/ S7-400. Available interfaces are:
• RS 232C,
• TTY or
• RS 422/485
These interfaces can be applied either individually or as a combina-
tion (in case of CP 441-2). For transferring user data the following
protocols are used:
• 3964 (R),
• ASCII
• RK 512 protocol
• Loadable protocol driver like Modbus or Data
Highway DF1.
Not all of the protocols are supported by modules.

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Module Description
PROFIBUS interfaces
(e.g. CP 342-5 /
CP 443-5 Extended,
IM467, CP 343-5 /
CP 443-5 Basic)
The following protocols can be used with the PROFIBUS interface:
• FDL protocol
• S7 protocol
• DP protocol
• FMS protocol
Here, only combinations with the DP or FMS protocol are offered by
the individual CPs. The interface module has exclusively been de-
signed for the DP protocol.
Industrial Ethernet
(z.B. CP 343-1/
CP 443-1,
CP 343-1 IT /
CP 443-1 IT,
CP 444, CP 343-1 PN)
The interfaces of the Industrial Ethernet offer the highest transmis-
sion rate of the interfaces introduced here. They can also be used
for cost-effective connections of third-party systems or old systems.
The supported protocols are:
• ISO transport (restricted)
• ISO on TCP (RFC 1006)
• TCP
• UDP
• PROFInet
• FTP
• HTTP
• SMTP (only sending)
• MAP
Not all of the protocols are supported by modules.
ASI Master
(z.B. CP 343-2)
Via the AS-I bus it is possible to connect directly simple actuators or
sensors of specification 2.1. This version can be used for connect-
ing up to 62 AS-I slaves.

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1.4.3 WinAC-Basis/RTX
The following communication possibilities are available for the WinAC-
Basis/RTX:
Figure 1-7
Table 1-7
Module Description
MPI interfaces
(e.g. CP 5611)
The MPI interface represents primarily a programming interface.
Furthermore, it is designed as a dynamic data interface for the ex-
change with S7 micro-controllers as well as for the data communica-
tion to an HMI application.
PROFIBUS interfaces
(e.g. CP 5611,
CP 5613)
The PROFIBUS interface of the WinAC is used as PROFIBUS DP
master or as communication interface with other S7 systems via the
S7 protocol. HMI function is additionally possible. There are no
other PROFIBUS standard protocols available in the system.
faces
(e.g. CP 1611,
CP 1613)
The Industrial Ethernet interface of the WinAC is suitable for ex-
changing larger data amounts with other S7 systems. It can also be
used to program the controller or operate via HM systems.
Special features of the WinAC-Basis/RTX
With its position as a mere Soft PLC, the WinAC Basis takes a special
status among the S7 controllers. Via the additional software package ”In-
dustrial Data Bridge” it is also able to use indirectly other communication
protocols by means of the OPC server. However, out of all the standard
functions the WinAC-Basis/RTX is only fixed to the DP and S7 communica-
tion.

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It is necessary to install the Simatic Net Software for using the communica-
tion services.
1.4.4 WinAC-Slot
The following communication possibilities are available for the WinAC-Slot:
Figure 1-8
Table 1-8
Module Description
CPU-internal
interface
The WinAC-Slot offers (CPU 412 or CPU 416) two internal inter-
faces in both versions:
• An MPI / DP interface and
• A DP interface
Both interfaces can be used as DP master interface. The MPI / DP
interface can be used either as MPI or DP interface for remote pro-
gramming, or for connecting to other S7 controllers or for HMI appli-
cations, without having to use another CP.
MPI interfaces
(e.g. CP 5611)
The MPI interface represents primarily a programming interface.
Furthermore, it can be used as a dynamic data interface for the
exchange with S7 micro-controllers as well as for the application as
data interface for micro-HMI applications.
PROFIBUS interfaces
(e.g. CP 5611,
CP 5613)
The PROFIBUS interface of the WinAC is used as PROFIBUS DP
master or as communication interface with other S7 systems via the
S7 protocol. HMI function is additionally possible. There are no
other PROFIBUS standard protocols available in the system.

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Module Description
faces
(e.g. CP 1611,
CP 1613)
The Industrial Ethernet interface of the WinAC is suitable for ex-
changing larger data amounts with other S7 systems. It can also be
used to program the controller or operate via HM systems.
Special features of the WinAC-Slot
The WinAC-Slot is a mixture of a mere HW controller and a Soft-PLC. By
using the Slot CPU as hardware plug-in card (PCI or ISA format) it works
out the PLC program independently from the PC CPU. By means of the
software package “T-Kit“, an additional software data interface is available
enabling a direct data exchange with PC applications.

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2 Bus-oriented Selection Aid of Usable Protocols
Introduction
In the following chapter the communication protocols available for this case
are shown by means of communication constellations. In addition all possi-
ble protocols are differentiated by using defined core criteria which can be
protocol-specific or bus-specific and programming-specific.
Contents of the selection aid
Table 2-1
Bus system Constellation Description
CPU connection
external
CPU connection between two stationsMPI Bus
CPU connection
internal
CPU connection within a rack without
using the backplane bus
PB CPU – CP
connection
PROFIBUS communication between the
central processing unit and communication
processor
PB CP – CP
connection
PROFIBUS communication between
communication processors
PB CPU – CPU
connection
PROFIBUS communication between cen-
tral processing units
PROFIBUS
PB Broadcast / Multi-
cast
PROFIBUS communication with multicast /
broadcast functionality
IE CPU – CP connec-
tion
Industrial Ethernet communication be-
tween the central processing unit and
communication processor
IE CP – CP connection Industrial Ethernet communication be-
tween communication processors
IE CPU – CPU
connection
Industrial Ethernet communication be-
tween central processing units
Industrial
Ethernet
IE Broadcast /
Multicast
Industrial Ethernet communication with
multicast / broadcast functionality
PtP- connection PtP connection between two stationsSerial
interface PtP Multicast / Broad-
cast
PtP communication with multicast / broad-
cast functionality
SIMATIC
backplane
bus
Backplane bus con-
nection
Backplane bus communication between
two stations

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2.1 MPI bus
Introduction
The following chapter shows successively all possible hardware constella-
tions enabling a data transfer via the MPI bus.
Detailed bus description
You will find a detailed bus description of the bus system discussed here in
the document “Selection criteria for networks and services”.
http://support.automation.siemens.com/WW/view/en/21045102
Structure of the chapter
The chapter MPI bus deals with the following 2 hardware constellations:
Table 2-2
Constellation Description
CPU connection
external
The CPU connection between two individual control-
lers.
CPU connection
internal
CPU connection within a rack without using the back-
plane bus
Overview of the constellations
Each constellation is described by means of the following 4 information
units:
• Description of the connection case
• The matrix of the hardware constellations
• The core information of the available protocols
• An overview of the available sample applications for this constellation
Advantages of this consideration
This consideration enables the purposive selection of the hardware constel-
lation and out of this the selection of the applicable protocol.
All possible hardware constellations within the SIMATIC S7 family will be
viewed in each constellation. The following overview of protocols enables a
direct selection by comparing the functionalities of the applicable protocols.

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2.1.1 CPU connection external
Connection case
The task is to exchange data between two stations assigned to the same
MPI bus.
Hardware scheme
This hardware constellation is made up as follows:
Bild 2-1
Both stations, station 1 and station 2, consist of one CPU respectively.
They are built up physically separated from each other. And both stations
are coupled via the joint MPI bus. The data are to be transferred via this
connection.

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Which protocols can I use with this constellation?
The following table shows all applicable protocols for the respective hardware constellations. The following page provides further details of
the possible protocols.
Table 2-3
Station 1
Station 2
S7-200 S7-300 S7-400 WinAC-Slot WinAC-Basis/RTX
(as of V 4.0)
S7-200 X
(only PPI connection pos-
sible)
S7 basis communication
(partner 2 as server via
XPUT / XGET)
S7 communication
(partner 2 as server)
XPUT / XGET)
S7 communication
(partner 2 as server)
XPUT / XGET)
S7 communication
S7-300 X S7 basis communication
global data
S7 communication
(partner 1 as client
partner 2 as server)
global data
S7 communication
(partner 1 as client
partner 2 as server)
global data
S7 communication
S7-400 X S7 basis communication
global data
S7 communication
global data
S7 communication
global data
S7 communication
WinAC-Slot X S7 basis communication
global data
S7 communication
global data
S7 communication
global data
S7 communication
WinAC
Basis/RTX
(ab V 4.0)
X X S7 communication S7 communication S7 communication
= not applicable

Rev. A - Endgültig 12.04.2004 24/185
Overview of the properties of the MPI bus protocols
With the following overview you can evaluate the properties of the applicable protocols by means of chosen core properties.
Table 2-4
S7 basic communication S7 communicationProtocol
Service
Criterion
XPUT / XGET XSEND / XRECV BSEND / BRCV USEND / URCV PUT / GET
Global data
Data range 1 - 84 bytes 1 -76 bytes 1 – 32768 (S7-300) /
65535 (S7-400) bytes
1 – 165 bytes 1 – 165 bytes 1 - 22 bytes (S7-300) /
1 - 64 bytes (S7-400)
Consistency Only guaranteed when
sending
Yes Throughout the whole length 8 bytes throughout
the whole length
Yes
Acknowledgement
mechanism
Operating system of the controller Level 7
implemented
Operating system of the controller Operating system of the
controller
Connected stations 1 – 1 unidirectional 1 – 1
bidirectional
1 – 1
bidirectional
1 – 1 unidirectional 1-1 / 1-n bidirectional
Configuration type Non-configured connection Bilaterally configured Unilaterally config-
ured
Bilaterally configured
Connection type Dyn. / stat connection
Client / Server
Dyn. / stat connection
Client / Client
Stat connection Client / Client Stat. connection
Client / Server
Stat connection Client /
Client
Data connec-
tion suitable
for:
Small data amounts Medium to large data
amounts
Small data amounts Smallest data amounts
Performance
Evaluation In case of static connections
In case of dynamic connections
Configuration effort None Low Medium
Pogramming effort Medium Medium Medium
Connection of
old systems (S5 ) /
third party systems
No No No

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Evaluating the performance of the used protocols
The evaluation of the performance statement of the above table is partly
made on the basis of the available measurements resulting from the com-
munication examples in the Application Portal and partly on the basis of
previous experiences when using protocols.
Application samples
For this constellation, “CPU connection external via MPI”, there are several
pre-coded examples which are available in the Application Portal.
Table 2-5
Application title/ Entry-ID Description
S7 Communication via Profibus CPs with
BSEND / BRECEIVE and several Job Refer-
ences (R_IDs)
Entry-ID: 20987358
This application is an automatic test program to
exchange data between two stations on up to 4
R_Ids, respectively via an S7 connection, when
operated under stress i.e. continuous data ex-
change between the stations. The application can
recognize occurring mistakes and can react pur-
posively (predetermined).
Client server communication between WinAC
Basis and S7.200 station via S7 communication
(PUT/GET)
Entry-ID: 20987586
This Application describes the synchronization of
substations via a server station. When requested,
the server station transfers up to 3 different data
records to the substations.
N to 1 synchronization of data in the MPI net-
work via S7 basic communication (X_SEND/
X_RCV)
Entry-ID: 19017849
a system of four S7 300 stations. Triggered by
means of a digital input, three S7 station send
data via a dynamic connection to a defined mas-
ter.
Back to the bus-oriented selection aid

Rev. A - Endgültig 12.04.2004 26/185
2.1.2 CPU connection internal
Connection case
The task is to exchange data between two stations which are arranged in
the same rack and assigned to the same MPI bus.
Hardware scheme
Figure 2-2
The stations consist of two CPUs with the respective I/O modules. They are
both set up in the same rack. Both stations are additionally coupled via the
joint MPI bus, apart from the mutually used communication bus. The data
are to be transferred via the MPI bus connection.
Note
The configuration on hand is a special case. The described configuration is usu-
ally carried out via the backplane bus connection which can be used, too.

Rev. A - Endgültig 12.04.2004 27/185
Table 2-6
Station 1
Station 2
S7-200 S7-300 S7-400 WinAC-Slot WinAC-Basis/RTX
(ab V 4.0)
S7-200
S7-300
S7-400 S7 basis communication
S7 communication
global data
WinAC-Slot
WinAC Basis/RTX
(ab V 4.0)
= not applicable

Rev. A - Endgültig 12.04.2004 28/185
Overview of the properties of the MPI bus protocols
Table 2-7
Service
Criterion
XPUT / XGET XSEND / XRECV BSEND / BRCV USEND / URCV PUT / GET
Global data
Data range 1 - 84 bytes 1 -76 bytes 1 – 32768 (S7-300) /
65535 (S7-400) bytes
1 – 165 bytes 1 – 165 bytes 1 - 22 bytes (S7-300) /
1 - 64 bytes (S7-400)
Consistency Only guaranteed when
sending
Yes Throughout the whole length 8 bytes throughout
the whole length
Yes
Acknowledgement
mechanism
Implemented
Operating system of the controller Operating system of the
controller
Connected stations 1 – 1 unidirectional 1 – 1
bidirectional
1 – 1
bidirectional
1 – 1 unidirectional 1-1 / 1-n bidirectional
Configuration type Non-configured connection Bilaterally configured Unilaterally config-
ured
Bilaterally configured
Connection type Dyn. / stat connection
Client / Server
Dyn. / stat connection
Client / Client
Stat connection Client / Client Stat. connection
Client / Server
Stat connection Client /
Client
Data connec-
tion suitable
for:
amounts
Small data amounts Smallest data amounts
Performance
Evaluation In case of static connection
In case of dynamic connection
Connection of
old systems ( S5 ) /
third party systems
No No No

Rev. A - Endgültig 12.04.2004 29/185
The evaluation of the performance statement of the above table is partly
made on the basis of the available measurements resulting from the com-
munication examples in the Application Portal and partly on the basis of
previous experiences when using protocols.
Application samples
For this constellation, “CPU connection external via MPI”, there are several
pre-coded examples which are available in the Application Portal.
Table 2-8
N to 1 synchronization of data in the MPI net-
work via S7 basic communication (X_SEND/
X_RCV)
Entry-ID: 20989875
a system of four S7 300 stations. Triggered by
means of a digital input, three S7 station send
data via a dynamic connection to a defined mas-
ter.
2.2 PROFIBUS
Introduction
tions enabling a data transfer via the PROFIBUS.
The chapter PROFIBUS deals with the following 4 hardware constellations:

Rev. A - Endgültig 12.04.2004 30/185
Table 2-9
PB CPU – CP connection PROFIBUS communication between the central
processing unit and communication processor
PB CP – CP connection PROFIBUS communication between communica-
tion processors
PB CPU – CPU connection PROFIBUS communication between central proc-
essing units
PB Broadcast / Multicast PROFIBUS communication with multicast / broad-
cast functionality
units:
2.2.1 PB CPU – CP connection
Connection case
PROFIBUS.
Hardware scheme

Rev. A - Endgültig 12.04.2004 31/185
Figure 2-3
Both stations, station 1 and station 2, consist of one CPU respectively. Sta-
tion 2 uses a communication processor for the connection to PROFIBUS.
The data are to be transferred via this PROFIBUS connection.

Rev. A - Endgültig 12.04.2004 32/185
Table 2-10
Station 1
Station 2
S7-200 S7-300 S7-400 WinAC-Slot WinAC Basis/RTX
(ab V 4.0)
(station 1 DP master,
station 2 DP slave)
DP communication
station 2 DP slave)
S7 communication
DP communication
station 2 DP slave)
S7 communication
DP communication
S7 communication / DP
communication
S7-300 DP communication S7 communication / DP
communication
communication
communication
S7-400 S7 communication S7 communication S7 communication
WinAC-Slot S7 communication S7 communication S7 communication
WinAC Basis/RTX
(ab V 4.0)
S7 communication S7 communication S7 communication
= nicht anwendbar

Rev. A - Endgültig 12.04.2004 33/185
Overview of the properties of the PROFIBUS protocols
Table 2-11
Sevice
Criterion
IPUT / IGET BSEND / BRCV USEND / URCV PUT / GET
DP communication
Data range 1 - 84 bytes / 1 - 94 bytes 1 – 32768 (S7-300) /
65535 (S7-400) bytes
1 – 165 bytes 1 – 165 bytes 1 – 244 bytes inputs /
1 – 244 bytes outputs
Consistency Only guaranteed when sending Throughout the whole length 8 bytes throughout the
whole length
Between 122 bytes and
whole length
Acknowledgement
mechanism
implemented
Operating system of the controller In the PROFIBUS ASIC implemented
mechanism + level 7 implementation
via the user program
Connected stations 1 – 1
bidirectional
1 – 1
bidirectional
1 – 1 unidirectional 1-1 bidirectional
Configuration type Non-configured connection Bilaterally configured Unilaterally configured Bilaterally configured
Connection type Dyn. / stat connection Client / Server Stat connection Client / Client Stat. connection Client
/ Server
Stat. connection Client / Server
Data connec-
tion suitable
for:
amounts
Small data amounts Small data amounts
Performance
Evaluation In case of static connection
In case of dynamic connection
Connection of
third party systems
No No Yes

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The evaluation of the performance statement of the above table is made on
the basis of the available measurements resulting from the communication
examples in the Application Portal and of previous experiences when using
protocols. Some representative comparison values as an illustration:
Table 2-12
Protocol
Data
S7 communication
BSEND / BRECEIVE
DP communication
Approx. 200
bytes
Approx. 95 ms Approx. 79 ms from master to slave*
Approx. 39 ms from slave to master*
* The measured value for the DP protocol is based on a measurement with implemented level 7 acknowl-
edgement via the user program of 2 stations. The typical DP cycle time is 3 ms.
These measurements are based on the following general requirements:
• Baudrate 1.5 MBit/s
• Busprofil standard
• Two stations at the bus.
Application samples
For this constellation, CPU – CP connection via PROFIBUS, the following
pre-coded examples have been created which are available in the Applica-
tion Portal.
Table 2-13
ences (R_IDs)
Entry-ID: 20987358
Routing of data records reaching over the sub-
network via a gateway CPU with S7 communi-
cation (BSEND/BRECEIVE)
Entry-ID: 20983154
By means of a fully programmed example, this
application shows an implementation of a func-
tioning routing of data records. Via a gateway
station, configurable data are sent from one sta-
tion to the other predefined station which is on
another network.
Client / server communication with (I) Slaves via
S7 basic communication (I_PUT/ I_GET)
Entry-ID: 20987910
The Application on hand offers a simple, quick
and practical learning startup into the cli-
ent/server specifications of the I_PUT/ I_GET S7
basic communication service and shows how to
deal with the configuration and user interfaces in
the SIMATIC.

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Data connection between separate DP systems
via DP communication
This application deals with a cost-effective trans-
fer of data between two DP masters by using a
DP slave CP 342-5. The DP additionally receives
a data acknowledgement, which will be evaluated
via the application.

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2.2.2 PB CP-CP connection
Connection case
PROFIBUS.
Hardware scheme
Figure 2-4
Both stations, station 1 and station 2, respectively consist of a CPU with a
connected PROFIBUS communication processor. The data are to be trans-
ferred via this PROFIBUS connection.

Rev. A - Endgültig 12.04.2004 37/185
Table 2-14
Station 1
Station 2
(ab V 4.0)
S7-200
(Here only server or slave)
S7 communication
(loadable PBK functions)
DP communication
station 2 DP slave)
S7 communication
DP communication
station 2 DP slave)
S7 communication
DP communication
communication
S7-300 S7 communication
FMS communication
FDL communication
DP communication
S7 communication
(per client/server)
FMS communication
FDL communication
DP communication
communication
communication
FMS communication
FDL communication
DP communication
S7 communication
(per client/server)
FMS communication
FDL communication
DP communication
communication
communication
WinAC-Slot S7 communication
WinAC
Basis/RTX
(ab V 4.0)
S7 communication
= not applicable

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On the following pages you will find an overview stating the properties of the applicable protocols. You can evaluate these protocols by
means of the selected core properties.
Table 2-15
Sevice
Criterion
DP communication
65535 (S7-400) bytes
whole length
whole length
Acknowledgement
mechanism
implemented
bidirectional
1 – 1
bidirectional
/ Server
Data connec-
tion suitable
for:
Smallest data amounts Medium to large data
amounts
Performance
In case of dynamic connections
Connection of
third party systems
No No Yes

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Part 2 of the table
Table 2-16
FDL FMSProtocol
Service
Criterion
SDA SDN READ WRITE REPORT
Data range 1 -240 bytes 1 – 236 bytes 1 – 237 bytes PDU
size*
1 – 233 bytes PDU
size*
1 – 233 bytes PDU
size*
Consistency Throughout the whole length Throughout the whole length 8 bytes throughout the
whole length
Acknowledgement
mechanism
Level 4 is
implemented
--- Level 7
Implemented
---
bidirectional
1 – 1 bidirectional
1 – n unidirectional
1 – 1
bidirectional
1 – n unidirectional
Configuration type Configured connection Bilaterally configured
Connection type Stat connection Client / Client Stat connection Client / Client Stat connection
Client / Client
Server / Client
Data connec-
tion suitable
for:
Small data amounts Medium data amounts Small data amounts
Perfor-
mance
Evaluation
Configuration effort Low Medium High
Pogramming effort Medium High
Connection of
third party systems
Yes Yes
*= In case of FMS, it is important to consider the usable variable description rather than the one of the usable PDU size.
By using structures, up to 76 structure elements can be packed up to a package and this package needs only a small amount of variable descriptions.
(In this connection see manual: SIMATIC NET NCM S7 for PROFIBUS / FMS)
In case of S7 and depending on the used CP, the amount of the variable description is built up as follows:

Rev. A - Endgültig 12.04.2004 40/185
Table 2-17
Variable descriptions in the S7 S7-300 S7-400
Server variable descriptions 256 512
Partner variable descriptions 256 2640
Table 2-18
Protocol
Data
S7 communication
BSEND / BRECEIVE
FDL
Service SDA
DP communication
Approx. 200
bytes
Approx. 95 ms Approx. 32 ms Approx. 79 ms from master to
slave*
Approx. 39 ms from slave to
master*
• Baudrate 1,5 MBit/s
• Bus profile standard
• Two stations at the bus
Application samples
For this constellation, PROFIBUBS CP to CP connection, the following pre-
coded examples have been created which are available in the Application
Portal.
Table 2-19
ences (R_IDs)
Entry-ID: 20987358
Data transfer via an FDL connection with SDA
via AG_SEND / AG_RECV
Entry-ID: 20987711
This application shows as to how a data transfer,
which can transfer any data amount up to a
maximum DB size, can be realized via a
PROFIBUS and by using the FDL protocol.
This transfer is made on acknowledged basis on
level 2 and additionally on level 7 which has been
realized within the application.

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Entry-ID: 20983154
By means of an fully programmed example, this
tion to other, predefined stations being on an-
other network.
Entry-ID: 20987910
the SIMATIC.
Entry-ID: 20987807
Basis and S7 200 station via S7 communication
(PUT/GET)
Entry-ID: 20987586

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2.2.3 PB CPU – CPU connection
Connection case
PROFIBUS.
Hardware scheme
Figure 2-5
Both stations, station 1 and station 2, consist of one CPU respectively. The
PROFIBUS is respectively connected to the integrated PROFIBUS inter-
face of the stations. The data are to be transferred via this connection.

Rev. A - Endgültig 12.04.2004 43/185
the protocols possible here.
Table 2-20
Station 1
Station 2
(ab V 4.0)
S7-200
(Here only server or slave)
DP communication
S7 communication
(Client/Server)
DP communication
S7 communication
(DP communication
communication
DP communication
DP communication
S7 communication
(Client/Server)
S7 communication /
DP communication
S7 communication /
DP communication
DP communication
S7 communication
(DP communication
S7 communication /
DP communication
S7 communication /
DP communication
WinAC-Slot S7 communication /
DP communication
S7 communication S7 communication
WinAC
Basis/RTX
(ab V 4.0)
= not applicable

Rev. A - Endgültig 12.04.2004 44/185
Table 2-21
Sevice
Criterion
DP communication
65535 (S7-400) bytes
whole length
whole length
Acknowledgement
mechanism
implemented
bidirectional
1 – 1
bidirectional
/ Server
Data connec-
tion suitable
for:
Smallest data amounts Medium to large data
amounts
Performance
In case of static connections
Connection of
third party systems
No No Yes

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Table 2-22 Text
Protocol
Data
S7 communication
BSEND / BRECEIVE
DP communication
Approx. 200
bytes
Approx. 95 ms Approx. 79 ms from master to slave*
Approx. 39 ms from slave to master*
• Baudrate 1.5 MBit/s
• Bus profile standard
• Two stations at the bus.
Application samples
For this constellation, CPU – CP connection via PROFIBUS, the following
pre-coded examples have been created which are available in the Applica-
tion Portal.
Table 2-23
ences (R_IDs)
Entry-ID: 20983154
Entry-ID: 20983154
By means of a fully programmed example, this
tion to the other predefined station which is on
another network.
Entry-ID: 20987910
the SIMATIC.

Rev. A - Endgültig 12.04.2004 46/185
Entry-ID: 20987807
Basis and S7 200 station via S7 communication
(PUT/GET)
Entry-ID: 20987586

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2.2.4 PC Broadcast / Multicast
Connection case
The task is to exchange data between any amounts of stations assigned to
the same PROFIBUS.
Hardware scheme
Figure 2-6
All stations, Station 1, Station 2 up to Station n, consist of respectively one
CPU as well as a corresponding PROFIBUS communication processor.
The PROFIBUS is connected to the respective PROFIBUS interface of the
communication processor. Via this connection the data are to be trans-
ferred from one station to all communication partners which can be ac-
cessed.

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Table 2-24
Station 1
Station 2
(ab V 4.0)
S7-200
S7-300 FDL communication
(service FDL SDN Multi or
Broadcast)
FMS communication
(FMS Broadcast)
FDL communication
Broadcast)
FMS communication
(FMS Broadcast)
S7-400 FDL communication
Broadcast)
FMS communication
(FMS Broadcast)
FDL communication
Broadcast)
FMS communication
(FMS Broadcast)
WinAC-Slot
WinAC
Basis/RTX
(as of V 4.0)
= not applicable

Rev. A - Endgültig 12.04.2004 49/185
Table 2-25
FDL FMSProtocol
Service
Criterion
SDN REPORT
Data range 1 – 236 bytes 1 – 233 bytes PDU size*
Consistency Throughout the whole length 8 bytes throughout the whole
length
Acknowledgement
mechanism
--- ---
Connected stations 1 – n unidirectional 1 – n unidirectional
Configuration type Configured connection Bilaterally configured
Connection type Stat connection Client / Client Stat connection
Client / Client
Server / Client
Data connec-
tion suitable
for:
Perfor-
mance
Evaluation
Configuration effort Medium High
Pogramming effort Medium High
Connection of
third party systems
Yes Yes
*= In case of FMS, it is important to consider the usable variable description rather than the one of the usable PDU size.
By using structures, up to 76 structure elements can be packed up to a package and this package needs only a small amount of variable descriptions.
(In this connection see manual: SIMATIC NET NCM S7 for PROFIBUS / FMS)

Rev. A - Endgültig 12.04.2004 50/185
protocols.

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2.3 Industrial Ethernet
Introduction
tions enabling a data transfer via the Industrial Ethernet.
The chapter Industrial Ethernet deals with the following 4 hardware con-
stellations:
Table 2-26
IE CPU-CP connection Industrial Ethernet communication between a central
processing unit and a communication processor
IE CP-CP connection Industrial Ethernet communication between two
communication processors
IE CPU-CPU connection Industrial Ethernet communication between two cen-
tral processing units
IE Broadcast / Multicast Industrial Ethernet communication with multicast /
broadcast functionalities
units:

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2.3.1 IE CPU – CP connection
Connection case
The task is to exchange data between two stations connected via the
Ethernet.
Hardware scheme
Figure 2-7
Station 1 consists of a CPU which is directly connected to the Ethernet via
an Ethernet Interface. Station 2 consists of CPU with the corresponding
Ethernet communication processor. The data are to be transferred via this
connection.

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Table 2-27
Station 1
Station 2
(ab V 4.0)
WinAC-Slot S7 communication
WinAC Ba-
sis/RTX (ab V
4.0)
S7 communication
= not applicable

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Overview of the properties of the Industrial Ethernet protocols
With the following overview you can evaluate the properties of the applicable pro-
tocols by means of chosen core properties.
Table 2-28
S7 communicationProtocol
Service
Criterion
BSEND / BRCV USEND / URCV PUT / GET
Data range 1 – 32768 / 65535
bytes
1
1 – 440 bytes 1 – 400 bytes
Dyn. data length Yes
Consistency Throughout the whole length 8 bytes throughout
the whole length
Acknowledgement
mechanism
Level 7
implemented
Operating system of the controller
bidirectional
1 – 1 unidirectional
Configuration type Bilaterally
configured
Unilaterally config-
ured
Connection type Stat connection
Client / Client
Stat. connection
Client / Server
Data connection
suitable for:
Medium to large
data amounts
Small data amounts
Perfor-
mance
Evaluation
Suitable for routing Yes
Configuration effort Low
Pogramming effort Medium
Connection of
old systems ( S5 ) / third
party systems
No / No
Table 2-29
Protocol
Data
S7 communication
BSEND / BRECEIVE
Approx. 200
bytes
Approx. 95 ms
• Baudrate 100 MBit/s, full duplex
• Crossover cabling

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Application samples
For this constellation, CPU – CP connection via Industrial Ethernet, the fol-
lowing pre-coded examples have been created which are available in the
Application Portal.
Table 2-30
ences (R_IDs)
Entry-ID: 20987358
This application is an automatic test program to ex-
change data between two stations on up to 4 R_Ids,
respectively via an S7 connection, when operated
under stress i.e. continuous data exchange between
the stations. The application can recognize occurring
mistakes and can react purposively (predetermined).
Routing of data records reaching over the
subnetwork via a gateway CPU with S7
communication (BSEND/BRECEIVE)
Entry-ID: 20983154
By means of a fully programmed example, this appli-
cation shows an implementation of a functioning
routing of data records. Via a gateway station, con-
figurable data are sent from one station to the other
predefined station which is on another network.
Basis and S7 200 station via S7 communica-
tion (PUT/GET)
Entry-ID: 20987586
substations via a server station. When requested, the
server station transfers up to 3 different data records
to the substations.

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2.3.2 IE CP – CP connection
Connection case
The task is to exchange data between two stations containing an Ethernet
CP.
Hardware scheme
CPU-1 CPU-2
Station1 Station2
IE
DBWxy DBWxy
CP IExCP IEx
Figure 2-8
Both systems, Station 1 and station 2, respectively consist of a CPU with
the corresponding Ethernet communication processor. The data are to be
transferred between both systems via this connection.

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The following table shows all applicable protocols for the respective hardware constellations. Further information on possible protocols is
available on the next page.
Table 2-31
Station1
Station2
(as of V 4.0)
S7-200 S7 communication S7 communication
ISO transport protocol
TCP protocol
ISO on TCP protocol
UDP protocol
S7 communication
TCP protocol
ISO on TCP protocol
UDP protocol
TCP protocol
ISO on TCP protocol
UDP protocol
S7 communication
TCP protocol
ISO on TCP protocol
UDP protocol
WinAC-Slot S7 communication S7 communication
WinAC
Basis/RTX
(ab V 4.0)

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Table 2-32
S7 CommunicationProtocol
Service
Criterion
ISO Transport
Protocol
ISO on TCP
Protocol
TCP Protocol UDP Protocol
BSEND/
BRCV
USEND / URCV PUT / GET
Data range 1 – 8192 bytes 1 – 8192 bytes 1 – 8192 bytes 1 – 2048 bytes 1 – 32768 / 65535
bytes
1
1 – 440 bytes 1 – 400 bytes
Dyn. data length Yes Yes No Yes Yes
Consistency Throughout the whole
length
Throughout the whole
length
length
length
Throughout the whole length 8 bytes throughout
the whole length
Acknowledgement
mechanism
Level 4
implemented
Level 4
implemented
Level 4
implemented
--- Level 7
implemented
bidirectional
1 – 1
bidirectional
1 – x broadcast only
sending
1 – 1 unidirectional/
bidirectional
1 – n multicast bidirec-
tional
1 – x broadcast only
sending
1 – 1
bidirectional
Configuration type Unilaterally / bilaterally
configured
Unilaterally / bilaterally
configured
configured
configured
Bilaterally
configured
ured
Client / Client
Stat connection
Client / Client
Stat connection
Client / Client
Stat connection
Client / Client
Stat connection
Client / Client
Stat. connection
Client / Server
Data connection
suitable for:
Small – medium
data amounts
Small – medium
data amounts
Small – medium
data amounts
Small data amounts Medium to large
data amounts
Small data amounts
Perfor-
mance
Evaluation
Suitable for routing No Yes Yes Yes Yes
Configuration effort Low Low Low Medium Low
Pogramming effort Medium Medium High Medium, when acknowl-
edging high
Medium
Connection of
party systems
Yes / No Yes (conditional)
2
/
Yes (conditional)
Yes (conditional)
2
/ Yes Yes (conditional)
2
/ Yes No / No
1
: Depending on the used controller ;
2
: When using the CP 1430 TCP

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Evaluation of the performance by means of the available applications
The evaluation of the performance statement of the above table is made on the basis of the available measurements resulting from the
communication examples in the Application Portal and of previous experiences when using protocols. A representative comparison value
as an illustration:
Table 2-33
Protocol
Data
ISO on TCP protocol UDP protocol S7 communication with the
service “BSEND / BRECV“
2048 bytes Approx. 90 ms Approx. 105 ms Approx. 700 ms
* The measured value for the UDP is based on a measurement with implemented level 7 acknowledgement via the user program of 2 stations.
• Used bus profile: 100 MBit full duplex
• Connection via a connection, except the UDP result, as a partially defined connection is used as an acknowledgement mechanism of
both partner stations.
• The acknowledgement mechanisms of level 4 or 7 are used; in this case, a simple acknowledgement mechanism has been
subsequently implemented into the program for the UDP protocol.

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Application samples
For this constellation, CPU – CP connection via Industrial Ethernet, the fol-
lowing pre-coded examples have been created which are available in the
Application Portal.
Table 2-34
ences (R_IDs)
Entry-ID: 20987358
This application is an automatic test program to ex-
change data between two stations on up to 4 R_Ids,
respectively via an S7 connection, when operated
under stress i.e. continuous data exchange between
the stations. The application can recognize occurring
mistakes and can react purposively (predetermined).
Comparison of data transfer via one and via
four parallel ISO-on-TCP connections on
Industrial Ethernet
Entry-ID: 20987359
This Application deals with a comparison between
the sending of a variable data record via one or four
Ethernet connections.
Master-slave communication via Ethernet
with UDP using multicast and unspecified
connections
Entry-ID: 20983558
This application shows how to realize an acknowl-
edged data transfer to a number of bus stations
(stations) which are variable and dynamically
changeable during runtime via Industrial Ethernet
and UDP without having to modify the configuration /
programming for each station. The master generates
multicast messages; the reception of these mes-
sages is acknowledged by the slaves by means of
unspecified connections.
Routing of data records reaching over the
subnetwork via a gateway CPU with S7
communication (BSEND/BRECEIVE)
Entry-ID: 20983154
By means of a fully programmed example, this appli-
cation shows an implementation of a functioning
routing of data records. Via a gateway station, con-
figurable data are sent from one station to the other
predefined stationwhich is on another network.
Basis and S7 200 station via S7 communica-
tion (PUT/GET)
Entry-ID: 20987586
substations via a server station. When requested, the
server station transfers up to 3 different data records
to the substations.

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2.3.3 IE CPU – CPU connection
Connection case
The task is to exchange data between two stations respectively containing
an on-board Ethernet interface.
Hardware scheme
Figure 2-9
Both systems, Station 1 and station 2, respectively consist of a CPU with
integrated Ethernet communication interface. The data are to be transferred
between both systems via this connection.

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Table 2-35
Station 1
Station 2
(ab V 4.0)
S7-200
S7-400
WinAC-Slot
WinAC
Basis/RTX (as of
V 4.0)
= not applicable

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Table 2-36
S7 communicationProtocol
Service
Criterion
BSEND / BRCV USEND / URCV PUT / GET
Data range 1 – 32768 / 65535
bytes
1
1 – 440 bytes 1 – 400 bytes
Consistency Throughout the whole length 8 bytes throughout
the whole length
Acknowledgement
mechanism
Level 7
implemented
bidirectional
Configuration type Bilaterally
configured
ured
Client / Client
Stat. connection
Client / Server
Data connection
suitable for:
Medium to large
data amounts
Small data amounts
Perfor-
mance
Evaluation
Configuration effort Low
Pogramming effort Medium
Connection of
party systems
No / No
Evaluating the performance of the evaluated protocols
Table 2-37
Protocol
Data
S7 communication
BSEND / BRECEIVE
Approx. 200
bytes
Approx. 95 ms
• Baudrate 100 MBit/s, full duplex
• Crossover cabling

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2.3.4 IE Broadcast / Multicast
Connection case
The task is to exchange data between two or several stations respectively
containing an Ethernet interface.
Hardware scheme
Figure 2-10
Each of these systems, Station 1, Station 2 up to Station n, respectively
consists of a CPU as well as an Ethernet communication processor. Via
these connections between the different systems, a transmitter should
transfer data to all other systems.

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Table 2-38
Station 1
Station 2
(ab V 4.0)
S7-200
S7-300 UDP protocol
(UDP multicast)
UDP protocol
(UDP multicast)
S7-400 UDP protocol
(UDP multicast)
UDP protocol
(UDP multicast)
WinAC-Slot
WinAC
Basis/RTX (as of
V 4.0)
= not applicable

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Table 2-39
Protocol
Criterion
UDP Protocol
Data range 1 – 2048 bytes
Consistency Throughout the whole length
Acknowledgement
mechanism
---
Connected stations 1 – n multicast bidirectional
1 – x broadcast only sending
Configuration type Unilaterally / bilaterally
configured
Client / Client
Data connection
suitable for:
Small data amounts
Perfor-
mance
Evaluation
Configuration effort Medium
Pogramming effort Medium, when acknowledg-
ing high
Connection of
party systems
Yes (conditional)
2
/ Yes
Evaluation of the performance by means of the available applications
examples in the Application Portal. A representative comparison value as
an illustration:
Table 2-40
Protocol
Data
UDP protocol
2048 bytes Approx. 105 ms
* The measured value for the UDP is based on a measurement with implemented level 7
acknowledgement via the user program of 2 stations.
• Used bus profile: 100 MBit full duplex

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Application samples
For this constellation, multicast/broadcast communication via Industrial
Ethernet, the following pre-coded examples have been created which are
available in the Application Portal.
Table 2-41
Master-slave communication via Ethernet
with UDP using multicast and unspecified
connections
Entry-ID: 20983558
This application shows how to realize an acknowl-
edged data transfer to a number of bus stations
(stations) which are variable and dynamically
changeable during runtime via Industrial Ethernet
and UDP without having to modify the configuration /
programming for each station. The master generates
multicast messages; the reception of these mes-
sages is acknowledged by the slaves by means of
unspecified connections.
2.4 Serial Interface
Introduction
tions enabling a data transfer via the serial interfaces.

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The chapter Serial Interfaces deals with the following two hardware constel-
lations:
Table 2-42
PtP connection PtP connection between two stations
PtP multicast / broadcast PtP communication with multicast / broadcast func-
tionality
units:

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2.4.1 PtP- connection
Connection case
The task is to exchange data between two stations connected via a serial
interface.
Hardware scheme
Figure 2-11
Both stations, station 1 and station 2, respectively consist of a CPU and
communication processor with serial interface. Both stations are physically
connected with each other by means of the same type of serial interface of
the respective DP via an adequate connection cable. The data are trans-
ferred via the available interface variants and the protocol driver available
for it.

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Table 2-43
Station 1
Station 2
S7-200
RS 485(RS 232), modem
S7-300
RS 232, TTY, RS 422/485
S7-400
RS 232, TTY, RS 422/485
S7-200 Free ASCII protocol Free ASCII protocol
Modbus (via modem)
Free ASCII protocol
Modbus (via modem)
S7-300 Free ASCII protocol ASCII
3964(R)
RK512
loadable driver (e.g.: Mod-
bus, Data Highway)
ASCII
3964(R)
RK512
loadable driver (e.g.:
Modbus, Data Highway)
S7-400 Free ASCII protocol ASCII
3964(R)
RK512
bus, Data Highway)
ASCII
3964(R)
RK512
bus, Data Highway)

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Overview of the properties of the serial protocols
Table 2-44
ModbusProtocol
Criterion
ASCII RK 512 3964(R)
Master Slave
Data Highway
Data range 1 – 1024 bytes 1 – 1024 bytes 1 – 1024 bytes 1 – 255 bytes 4 – 1024 / 4096 bytes (300/400)
Connected stations 1 – 1bidirectional 1 – 1bidirectional 1 – 1bidirectional 1 – 1bidirectional 1 – 1bidirectional
S7-200 1.2 kBit/s – 38.4 kBit/s
1
No No No Yes (via
modem)
No
S7-300 300 Bit/s – 76.8 kBit/s 300 Bit/s – 76.8 kBit/s 300 Bit/s – 76.8 kBit/s 300 Bit/s – 76.8 kBit/s 300 Bit/s – 76.8 kBit/s
RS232
Bridgeable distance 15 m 15 m 15 m 15 m 15 m
S7-200 No No No No No
20mATTY
Bridgeable distance 1000m 1000m 1000m 1000m 1000m
S7-200 300 Bit/s – 38.4 kBit/s No No No No
S7-300 300 Bit/s – 76.8 kBit/s 300 Bit/s – 76.8 kBit/s
2
300 Bit/s – 76.8 kBit/s
2
300 Bit/s – 76.8 kBit/s 300 Bit/s – 76.8 kBit/s
S7-400 300 Bit/s – 115.2 kBit/s 300 Bit/s – 115.2 kBit/s
2
300 Bit/s – 115.2 kBit/s
2
300 Bit/s – 76.8 kBit/s 300 Bit/s – 76.8 kBit/s
RS422/
RS485
Bridgeable distance 1200 m 1200 m 1200 m 1200 m 1200 m
Data connection
suitable for:
Small – medium data amounts Small – medium data amounts Small – medium data amounts Small data amounts Small – medium data amounts
Perfor
mance
Evaluation
Configuration effort Low Low Low High Medium
Pogramming effort Medium Medium Medium High Medium
Connection of
party systems
Yes / Yes Yes / Yes Yes / Yes Yes / Yes Yes / Yes

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1
) Can be achieved when using the PC/PPI cable.
2
) RS485 is not applicable here.
Evaluation of the performance
the basis of the experiences relating to these protocols.

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2.4.2 PtP Multicast / Broadcast
Connection case
The task is to exchange data from one station to several stations connected via a serial
interface.
Hardware scheme
Figure 2-12
The stations, Station 1, Station 2 up to Station n, respectively consist of one
CPU as well as a serial communication processor. All stations are physi-
cally connected with each other via the serial interface. The data are trans-
ferred via the respectively available interface variants and the available pro-
tocol driver.
Note: Possible interfaces
Only the interfaces of type RS 485 / 422 can be used for multi-point applications
without any further technical installation.

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Table 2-45
Station 1
Station 2 - n
S7-200
RS 485 SS
S7-300
RS 232, TTY, RS 422/485
S7-400
RS 232, TTY, RS 422/485
S7-200 via ´modem Loadable driver (e.g. Mod-
bus Master Broadcast)
Loadable driver (e.g. Mod-
S7-300 Loadable driver (e.g. Mod-
S7-400 Loadable driver (e.g. Mod-
= not applicable

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