Siemens CA 343 Series User manual

SIMATIC
S7 - OPEN MODBUS / TCP
Communication via CP343-1 and CP443-1
Manual
Preface, Table of Contents
Product Description
1
Getting Started
2
Commissioning
3
Licensing
4
FB MODBUSCP
5
Diagnostics
6
Application Samples
7
SIMATIC S7
OPEN MODBUS / TCP
Communication via
CP343-1 and 443-1
Manual
Appendices
Literature
Glossary
Edition 4.3
Safety Precautions and
Warnings
This manual contains warnings, which you should note for your own safety as well as for
the prevention of damage to property. These warnings are indicated by means of a triangle
and displayed as follows in accordance with the level of danger:
__________________________________________________________________
Danger
indicates that loss of life, severe personal injury or substantial damage
will result if proper precautions are not taken.
__________________________________________________________________
__________________________________________________________________
Warning
indicates that loss of life, severe personal injury or substantial damage can result if proper
precautions are not taken.
__________________________________________________________________
__________________________________________________________________
Caution
indicates that minor personal injury or property damage can result if proper precautions are
not taken.
__________________________________________________________________
__________________________________________________________________
Note
call attention to information that is especially significant to the product, handling of the
product or a specific part of this documentation.
__________________________________________________________________
Qualified
Personnel
The equipment may be commissioned and put into operation by qualified personnel only.
For the purpose of safety relevant warnings of this manual a qualified person is one who is
authorized to commission, ground and tag devices, systems and circuits.
Use as prescribed
Please note the following:
___________________________________________________________________
Warning
This equipment must only be used in applications as prescribed in the catalogue and the
technical description and in conjunction with equipment and components recommended and
authorized by Siemens.
Successful and safe operation of this equipment is dependent upon proper transport, and
storage, erection and installation as well as careful operation and maintenance.
®
®
SIMATIC and SIMATIC NET are registered trademarks of SIEMENS AG.
Trademarks
The other brand names in this manual may be trademarks use of which by third parties for
their purposes may infringe the proprietors’ rights.
Copyright © Siemens AG 2004-2009 All Rights Reserved
The reproduction, transmission or use of this document or its contents
is not permitted without express written authority. Offenders will be
liable for damages. All rights, including rights created by patent grant
or registration of a utility model or design, are reserved.
Siemens AG
Industry Sector
Engineering and Construction
I IS IN E&C
P.O. Box 3240, D- 91050 Erlangen
IT4.Industry@siemens.com
Exclusion from Liability
We have checked the contents of this document with regard to
conformity to the described hardware and software. Deviations,
however, cannot be excluded; therefore we cannot accept prejudice
for its complete conformity. The information in this document is
checked regularly and necessary corrections are contained in
subsequent issues. Any suggestions for improvement are gratefully
received.
We reserve the right to make technical changes.
Preface
Preface
Purpose of the
Manual
The information in this manual allows you to set up and put in operation the
connection between the CP 343-1/CP 443-1 and a device that supports the
Open MODBUS/TCP protocol.
Contents of the
Manual
This manual describes the function of the function block MODBUSCP and
its integration into the hardware and software of the communication
processors CP 343-1/CP 443-1.
The manual contains the following topics:
• Production description / Mounting
• Getting Started
• Commissioning
• Parameterization
• Licensing
• Function block MODBUSCP
• Diagnostics
• Application samples
Scope of this
Manual
This manual is valid for the following software:
Product
Identification number
From version
OPEN MODBUS / TCP
2XV9 450-1MB00
4.3
FB 108 “MODBUSCP”
1.3 / 2.2
FB 106 “MB_CPCLI”
1.2 / 2.2
FB 107 “MB_CPSRV”
1.2 / 2.1
Note
This manual contains the FB description, as it is valid at the time of
publication.
How to Access the
Information in this
Manual
To enable you a quick access to selected information, the manual provides
the following access aids:
•
The next pages contain a complete table of contents.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
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1
Preface
Additional
Sources of
Information
All additional information concerning CP 343/CP 443 (mounting,
commissioning etc.) can be found in the manual
SIEMENS
SIMATIC NET
S7-CPs for Industrial Ethernet
device manual C79000-G8900-C155
SIEMENS
SIMATIC NET
S7-CPs for Industrial Ethernet
device manual part B1
CP 343-1 / CP 343-1EX20
C79000-G8900-C158
SIEMENS
SIMATIC NET
S7-CPs for Industrial Ethernet
device manual part B4
CP 443-1
C79000-G8900-C152
SIEMENS
SIMATIC NET
NCM S7 for Industrial Ethernet
manual C79000-G8900-C129
Additional information concerning STEP7 can be found in the following
manuals:
SIEMENS
SIMATIC Software
Base software for S7 and M7
STEP7 user manual
C79000-G7000-C502-..
SIEMENS
SIMATIC Software
System software for S7-300/400
System and standard functions
Reference manual C79000-G7000-C503-02
Additional
Questions
If you have further questions regarding the use of the FBs described in this
manual, which are not answered in this document, please contact your
Siemens partner who supplied you with this function block.
Terminology
This document uses the term CP or CP 343/CP 443. The descriptions only
apply to communications processor CP 343-1/CP 443-1.
Scope of
Application
The function block described in this manual establishes a connection
between the CP 343-1/CP 443-1 and third party MODBUS devices.
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Table of contents
Table of Contents
1 ...... Product Description....................................................................................................... 1-1
1.1 ........ Field of Applications.......................................................................................... 1-1
1.2 ........ Hardware and Software Prerequisites.............................................................. 1-2
2 ...... Getting Started ............................................................................................................... 2-1
3 ...... Commissioning .............................................................................................................. 3-1
3.1 ........ Installing the Library on the STEP7 PG/-PC .................................................... 3-1
3.2 ........ Parameterization of the CP .............................................................................. 3-2
3.3 ........ Network Configuration ...................................................................................... 3-4
3.4 ........ How to Select the Appropriate Modbus Block .................................................. 3-9
3.5 ........ Insertion of the Function Blocks into the Program.......................................... 3-10
3.6 ........ Multiple Connections via Port 502 .................................................................. 3-12
3.7 ........ Start_up Characteristics of CP343 / CP443 ................................................... 3-13
3.8 ........ Changeover of a Previous Version to V4.x .................................................... 3-14
4 ...... Licensing ........................................................................................................................ 4-1
5 ...... Function Block MODBUSCP ......................................................................................... 5-1
5.1 ........ Functionality of the FB ...................................................................................... 5-1
5.2 ........ Parameters of the Function Block MODBUSCP .............................................. 5-4
5.3 ........ Address Mapping............................................................................................ 5-12
5.4 ........ Data and Standard Functions used by the FB ............................................... 5-15
5.5 ........ Renaming of Standard Functions ................................................................... 5-17
6 ...... Diagnostics..................................................................................................................... 6-1
6.1 ........ Diagnostics via the Display Elements of the CP .............................................. 6-1
6.2 ........ Diagnostic Messages of the FB MODBUSCP.................................................. 6-2
6.3 ........ Diagnostic Messages of FC5/FC6 and FC50/FC60......................................... 6-8
6.4 ........ Diagnostic Messages of included FCs/SFCs ................................................... 6-8
6.5 ........ Diagnostic Messages of SFC24 ....................................................................... 6-8
7 ...... Application Samples...................................................................................................... 7-1
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7.1 ........ Sample project STL .......................................................................................... 7-2
7.2 ........ Sample project CFC ......................................................................................... 7-3
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Product description
1
1.1
Product Description
Field of Applications
Placement in the
System Environment
The driver described here is a software product for the Communications
Processor CP343-1/CP443-1.
The CP343-1 can be used in the SIMATIC S7-300 automation system and
can establish communication links to partner systems.
CP443-1 can be used in the SIMATIC S7-400 automation systems and can
establish communication links to partner systems.
Function of the
FBs
These function blocks enable a communication link between CP343-1 /
CP443-1 and a device that supports the Open MODBUS/TCP protocol. The
function codes 1, 2, 3, 4, 5, 6, 15 and 16 are provided.
Data transmission is carried out following the Client-Server principle.
The SIMATIC S7 can act as both client and server during the data
transmission.
TCP/IP with
CP343-1 / CP443-1
TCP/IP with CP343-1 and CP434-1 uses static connections. The TCP
connection is not disconnected during errror-free operation.
Network configuration of STEP7 enables only a unique use of a specific
port number, when using TCP native stack of the CP.
However, with specific CP modules it is possible to use multiple connection
via port 502 to different clients simultaneously.
In section 3.6 “Mulitple connections via port 502” you can find technical details
regarding this matter.
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Product description
1.2
Hardware and Software Prerequisites
Usable Modules
You can find the latest hardware prerequisites on the internet:
www.siemens.com/s7modbus.
Software Versions
The usage of the modbus blocks is possible with STEP7 Version 5.4 or
higher. Withal the use of the blocks AG_LSEND/AG_LRECV V3.1 of the
update of SIMATIC NET library
(http://support.automation.siemens.com/WW/view/en/22172239) is required.
Memory
requirements
The FB MODBUSCP requires ca. 6k byte work and load memory.
The FB MB_CPCLI requires ca.10k byte work and memory.
The FB MB_CPSRV requires ca. 10 k byte work and load memory.
The particular length of the blocks can be determined in the properties of the
block in the Simatic Manager.
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Getting started
2
Getting Started
Procedure
1. Install “OpenModbusTCP CP“.
=> Section 3.1
2. Parameterize the connection parameters regarding your requirements
(IP-address, port number, etc.).
=> Section 3.2 to 3.4
3. Insert the Modbus function blocks into your SIMATIC project.
=> Section 3.6
4. Call the Modbus block FB108 in the required OBs.
=> Section 5.1
5. Parameterize the Modbus block for initialization (client/server, DB areas,
Modbus addresses) and runtime.
=> Section 5.2
6. Load the user program into the PLC and license the Modbus block for this
CPU.
=> Section 4
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Commissioning
3
Commissioning
General
Information
The configuration of the CP443-1/CP343-1 is possible via MPI or
LAN/Industrial Ethernet.
STEP7 is required with NCM S7 for Industrial Ethernet (shortly named
”NCM IE”).
The information below about STEP7 and the communication link configuration
refers to STEP7 Version 5.1 and NCM S7 Industrial Ethernet Version 5.1.
In later versions, the sequences, names and directories might be different.
Requirements
3.1
Knowledge of AWL and basic knowledge of STEP7 and PLC.
Installing the Library on the STEP7 PG/-PC
What We Provide
You
The attached CD contains a setup, which installs the library
“Modbus_TCP_CP”, 2 example projects and the manuals in English and
German in the corresponding STEP7 directories.
The manuals are available outside the setup additionally, to give you the
opportunity to get all information regarding the software without installation.
Requirements
To install, STEP7 must be installed. With older STEP7 versions the option
NCM S7 for Industrial Ethernet is necessary additionally.
Installation
Insert your Modbus CD into the CD-ROM drive and follow step-by-step the
instructions that are automatically displayed by the installation program. If the
installation program fails to automatically run, perform these steps:
1. Using Windows Explorer, navigate to the CD-ROM drive and go to the
directory setup and double-click Setup.exe file to start the installation
procedure.
2. Follow step-by-step the instructions that are displayed by the installation
program.
Now you can find
• the library in
\Program Files\Siemens\Step7\S7libs,
• 2 example projects in \Program Files\Siemens\Step7\Examples,
• the manual in
\Program Files\Siemens\Step7\S7manual\S7Comm,
• the software registration form in
\Program Files\Siemens\Step7\S7libs\Modbus_TCP_CP.
To access the Modbus library the first time, use the browse function of the
open dialog for libraries.
The manual can be accessed via short cut in \Program Files \Siemens
\Documentation as well.
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3.2
Parameterization of the CP
Parameterization
of the CP
If you have your stations connected with each other without a router, then
they have to be within the same subnet.
In the field Subnet connect the CP with the Industrial Ethernet. In order to do
that, select the entry with the name of your network. For newly created
networks this is normally “Ethernet(1)“.
Save and Compile the parameterization.
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Parameterization
of the
Communication
Partner
In the mode “CP is client” an “other station” is required for network
configuration.
After you have inserted the communication partner’s station into your STEP7
project (as described in “Project components: Insert ¾ Other station“) you
have to specify the object properties of the external station.
1) Properties – Other Station ¾ Interfaces
On the tab “Interfaces“ click on “New“. In the upcoming selection, select
“Industrial Ethernet” and click on “OK”.
This opens a dialog box “Properties – Ethernet Interface“. Enter an IP
Address that is in the same subnet as the communication partner’s station.
The subnet mask should be the same as the one of the partner’s station.
Select the associated subnet that connects the CP interface with the
communication partner’s interface.
Click on the “OK“ button. This will bring you back to the tab “Interfaces“.
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2) Properties – Other Station¾General
In tab “General” you do not have to make any settings.
3.3
Network Configuration
Communications
Connection
The CP is the link for the Industrial Ethernet connection between the S7-CPU
and the communication partner / bus. A connection configuration must be
made for the connection of the interfaces to the communication partner / bus.
Configure Network
in mode “CP is
Client”
In the STEP7 project, select the CPU in your S7 300/S7 400-Station and open
“Network configuration“ by double clicking “Connections”. This opens the
program “NetPro“ with which your connections can be configured.
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After selecting Insert¾ New Connection... the dialog box ”Insert new
connection“ will come up.
Select the connection partner (Other Station) for the new connection and use
“TCP Connection” for the connection. Put a check mark on “Show properties
dialog“
Click “OK“. This will take you back to the dialog box “Properties TCP
connection“.
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Object Properties
of the Connection
• An ID is provided. You can change the ID if needed.
• Click on the button “Routing” and the configured connection will be shown.
• The MODBUS client must execute “Active connection establishment”.
• In the register “Addresses” the port numbers are defined.
Click on “OK“ and the inputs are accepted.
Save the network configuration and close the program “NetPro“.
Please note that the connection ID (Local ID) has to be used when the FB is
called in the user program.
Selection of the
Port Number
In a MODBUS communication a MODBUS server are normally addressed via
port 502, whereas a MODBUS client uses a port from 2000.
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Unspecified
Connection with
“CP is server”
If you have got a communication with CP as MODBUS server, the
communication is set up as “unspecified connection”. The client must carry
out active connection establishment.
After selecting Insert¾ New Connection... the dialog box ”Insert new
connection“ will come up.
Select here “unspecified” instead of the communication partner and use
“TCP Connection” for the connection. Put a check mark on “Show properties
dialog“
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Click “OK“. This will take you back to the dialog box “Properties TCP
connection“.
The check box “active connection establishment” must not be activated.
In the register “addresses” all information regarding the partner, “IP” and
“PORT” are left blank.
Click on “OK“ and the inputs are accepted.
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3.4
How to Select the Appropriate Modbus Block
General
Information
The block FC10 AG_CNTRL of the SIMATIC_NET library permits to terminate
and reestablish an established connection. This block was also implemented
in the Modbus blocks for a more effective use of the resources of CPU and
CP. However, previous CPs or previous firmware releases do not support the
use of AG_CNTRL.
Therefore the library contains directories for both alternatives, each for
S7-300 CPs and S7-400 CPs:
•
Current CP 300
CPs of S7-300 which support AG_CNTRL
(not for CPU315 and 317 HW release V1)
•
Current CP 400
CPs of S7-400 which support AG_CNTRL
•
Previous CP 300
CPs of S7-300 which do not support
AG_CNTRL
•
Previous CP 400
CPs of S7-400 which do not support
AG_CNTRL
Pay attention to the count of local data of the used CPU! The required
local data for both alternatives are written in chapter 5.4.
Which CPs
support
AG_CNTRL?
Here you can find up-to-date information which CPs and which firmware
releases support AG_CNTRL:
Ethernet CPs and AG_CNTRL
If the used CP is not mentioned here, the Modbus blocks without AG_CNTRL
must be used.
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3.5
Insertion of the Function Blocks into the Program
Content of
MODBUS library
Insertion of the
MODBUS FBs
The following blocks are required for the Modbus communication:
•
MODBUSCP
•
MB_CPCLI
•
MB_CPSRV
In order to exchange data with MODBUS devices, you need the function
blocks MODBUSCP, MB_CPCLI, MB_CPSRV and AG_CNTRL if applicable.
To be able to insert this into your project you have to copy the function block
from the library. For that, open the library “Modbus_TCP_CP“ by selecting
the menu item File ¾ Open.
In the dialog box “Open Project“ select the tab ”Libraries“. Select the library
“Modbus_TCP_CP” using the Browse-Button and click “OK”.
This opens the library. Open the folder “CP 300” or “CP 400” according to
your Configuration by double clicking it. Select the function blocks and copy it
via “Edit ¾ Copy”. Then change back to your project .
In the Step7 project, in your opened S7 300/S7 400-Station, select the CPU.
Double click “S7-program”, and then “Blocks”.
This will open the “Blocks” folder.
Select “Edit ¾ Paste”. This will insert the block into your program.
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Insertion of the
Communication
Blocks
The Modbus function blocks use the function blocks AG_SEND and
AG_RECV in S7-300 or AG_LSEND and AG_LRECV in S7-400.
You can find these communication function blocks in the library
“SIMATIC_NET_CP“ which are included in the software package NCM S7
for Industrial Ethernet.
CP 300
Copy the functions FC5 (AG_SEND) and FC6 (AG_RECV) from the folder
“CP 300“ and insert in your project.
CP 400
Copy the functions FC50 (AG_LSEND) and FC60 (AG_LRECV) from the
folder “CP 400“ and insert in your project.
Please note, that the following versions of the FCs are a prerequisite for the
faultless function of the FB MODBUSCP:
S7-400:
AG_LSEND
AG_LRECV
V3.1 or higher
V3.1 or higher
S7-300:
AG_SEND
AG_RECV
V4.2 or higher
V4.7 or higher
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3.6
Multiple Connections via Port 502
General
Some CP modules are able to multiplex TCP connections. In doing so several
Modbus clients can establish a connection via port 502. The CP acts as
Modbus server.
Here you can find information which CP and which firmware release support
multiple connections via port 502:
www.siemens.com/s7modbus
Pre-requisits
To use the functionality, the parameterization must be carried out as follows:
•
CP is server
•
port 502 as local port
•
unspezified TCP connection in NETPRO
•
passive connection establishment
Please note that only 1 connection is parameterized in NETPRO irrespective
of the number of clients which address the CP as server.
Number of
Connections
The CP is capable to keep up to 8 connections to different clients. A ninth
attempt for connection establishment will be rejected.
Displaying the
Status of the
Connection
The status of the connection is displayed even in NETPRO online as well as
in special diagnosis of the CP.
As only 1 connection is parameterized in NETPRO, the display shows the
status of all TCP connections to the several clients.
As long as no client has established a connection “Passive connection
establishment in progress“ is displayed.
As soon as one client has established a connection “established” is displayed.
It is not possible to check how many clients have actually established a
connection to the CP.
Characteristics of
the Error Handling
The FB MODBUSPN and the CP respectively must terminate and reestablish
the connection in certain error situations. This action is carried out by the FB
MODBUSPN. Thereby all existing connections via port 502 are terminated.
Tip for your User
Program
When several connections are established via port 502, it is not possible to
identify the client which has sent the recent request.
If the clients use different UNIT numbers, the verification of the same in the
user program allows a determination.
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3.7
Start_up Characteristics of CP343 / CP443
Introduction
The start up of the CP is divided into the following phases:
• Initialization (Power on of the CP)
• Parameterization
Initialization
As soon as the CP is connected to power, the hardware self test runs. The
firmware of the CP is set up for operation.
Parameterization
During parameterization the CP receives the device parameters that are
assigned to its slot.
The CP is now ready for operation.
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3.8
Changeover of a Previous Version to V4.x
General
Information for
Changeover to
V4.0
If a previous version of "ModbusTCP CP" is already used, some changes
must be carried out in the S7 program. An update with the menu “file” ->
"check and update access" is not possible because the interface of the block
has changed.
Procedure for
Changeover to
V4.0
1. Copy the new Modbus blocks FB106, FB107, FB108 and DB3 into your
project.,You can rename the modbus blocks, if these block numbers are
already used.
2. Open the blocks, in which the modbus blocks have been called so far
(OB100 and cyclical OB).
3. Call the new block FB108 MODBUSCP directly after the prior MODBUS
or MODB4 call with a new instance DB.
4. Transcribe the following parameters of MODBUS or MODB4 to
MODBUSCP depending on the calling OB.
id, laddr, MONITOR, db_0 to db_8, ENQ_ENR, server_client,
START_ADDRESS, LENGTH, WRITE_READ, INPUT_HOLDING, TI,
UNIT, DONE_NDR, ERROR and STATUS.
Capital letters represent runtime parameters, small letters initialisation
parameters.
5. Add suitable values to the new parameters:
REG_KEY, single_write, data_type_x, LICENSED, BUSY and
STATUS_FUNC. It is not necessary to allocate the parameter
IDENT_CODE.
You can find the description of the new parameters in the parameter list in
section 5.2.
6. The output parameters are displayed dynamically, i.e. they are only
available for one PLC cycle. They have to be copied to an additional
memory area if you need to process them or to display the values in a
VAT (STEP7 variable table).
Adapt your program correspondingly.
7. Insert the programming fault block OB121 in your program if this has not
been included yet. This block is necessary for the licensing, see section
"licensing" for further information.
8. Delete the previous Modbus call or comment it out. Load the program into
the CPU and execute a restart of the CPU.
Notes to V4.3
Here you find information to V4.3: www.siemens.com/s7modbus, tab
“Downloads”.
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Licensing
4
Licensing
General
The block MODBUSCP must be licensed for each CPU individually. The
licensing takes place in two steps: reading the IDENT_CODE and declaring
the registration key REG_KEY. The OB121 must be available in the CPU.
Read the
IDENT_CODE
To read the IDENT_CODE please proceed as follows:
1. Parameterize the block MODBUSCP in the cyclic OB (OB1 or cyclic
interrupt OB) and in OB100 according to your requirements. Transfer
the program to the PLC and turn it to RUN mode.
2. Open the instance DB of the block MODBUSCP. „Data block“ ->
„Open Online“ to open the DB.
Monitoring the block via the button
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4-1
Licensing
3. The output IDENT_CODE shows an 18 character string
Copy this string per copy/paste from the DB und and insert it in the
form IT4Industry SOFTWARE REGISTRATION FORM. This form is
stored in the library path
..\Program Files\Siemens\Step7\S7LIBS\Modbus_TCP_CP
during installation and is also available on the installation CD.
Insert the License-No. of the product package into the form.
4. Please send the form per e-mail to IT4Industry
it4.industry@siemens.com.
Hereupon you will receive the registration key for your PLC.
Please note: No ident code can be displayed as long as an initialisation error
exists. Evaluate the output STATUS and correct the parameterization.
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Declaration of the
Registration Key
REG_KEY
The registration key REG_KEY must be declared for each call of the block
MODBUSCP.
The registration key REG_KEY should be stored in a global DB. Via this
global DB all MODBUSCP blocks can receive the registration key (See also
the following example).
Please proceed as follows to declare the registration key REG_KEY:
1. Copy the prepared license block DB3 of the library
“Modbus_TCP_CP“ into your project. If the DB number is already
used in your project, rename the license DB.
2. Open the license DB and copy the 17 digit registration key you
received from IT4industry to the column “Initial value”.
3. Declare the registration key in the data block as “initial value” to avoid
a repeated insertion after reloading the PLC. Open the data block in
the SIMATIC manager with the editor in the declaration view. Change
over to the data view via the menu “View” -> “Data View”. Choose in
the menu “Edit > Initialize Data Block” – all values of the column
“initial value” are copied to “actual values”.
4. Assign the value “DB3.REG_KEY” to the parameter REG_KEY of the
block MODBUSCP.
5. Transfer the changed blocks to the PLC. The registration key can be
set at run time. A STOP -> RUN transition is not necessary.
The block is now licensed for this CPU.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
4-3
Licensing
Missing or Wrong
Licensing
When the registration key is missing or a wrong one is detected, the SF LED
(S7-300) or the INTF LED (S7-400) of the CPU is flashing. A cyclic error
message regarding the missing license is displayed in the diagnostic buffer
too. The error number of the missing license is W#16#A090.
_____________________________________________________________
Warning
!
The CPU will turn to STOP mode, if the OB121 is not available.
_____________________________________________________________
Modbus communication is carried out even with a missing or wrong
registration key, but the output STATUS is set to W#16#A090 “no valid
license”.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
4-4
Function Block MODBUSCP
5
5.1
Function Block MODBUSCP
Functionality of the FB
General
Information
The function block MODBUSCP allows a communication between a CP443-1
and CP 343-1 and a partner, which supports Open MODBUS/TCP protocol.
The function codes 1, 2, 3, 4, 5, 6, 15 and 16 are supported.
Depending on the parameterization the FB can be operated both in client and
in server mode. It is also possible to operate a CP as a client and as a server
at the same time. In this case two NetPro connections and 2 FB calls are
necessary. In the operating mode server the functionality multitasking,
according to the MODBUS reference, is not implemented.
There is no limitation of the maximum number of parallel called modbus
blocks on the part of the library. Though it depends on the CPU and CP how
many AG functions can run simultaneously. The maximum number of AG
calls can be taken from the manual of the CPU: "Technical Data" >
"Communication". In the manual of the CP it’s detailed, how many
AG_SEND/AG_RECV or AG_LSEND/AG_LRECV can be processed by this
CP simultaneously.
The block MODBUSCP calls the blocks MB_CPCLI (FB106) and MB_CPSRV
(FB107) internally. The block MB_CPCLI comprises the function of Modbus
client, the block MB_CPSRV executes the function of Modbus server.
The function block performs the following functions:
•
Calls the standard functions for the data transfer between the CPU
and the CP
•
Generates MODBUS specific telegram header before send
•
Verification of the MODBUS specific telegram header after receive
•
Verification if the memory areas exist which are requested by the
client
•
Generate exception telegrams when failures occur (only when CP is
in server mode)
Exception
code
Meaning
1
The requested function code is not supported.
2
An access to a not existing or not permitted address
was carried out.
3
An invalid length was indicated for this function code.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
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5-1
Function Block MODBUSCP
•
Data transfer to and from the parameterized DB
•
Monitoring the data reception with a time-out
•
Verification of the registration key
Online-Help
In Simatic Manager an online help for function block MODBUSCP is provided.
Mark the FB and press the key “F1”. The online help is displayed; it contains
the main information regarding the FB.
Call of the FB
The function block MODBUSCP has to be called in two OBs:
• in the start up OB100 and
• in a cyclic OB (OB1 or cyclic interrupt OB, e.g. OB35)
In doing so the same instance DB has to be used.
The subordinate blocks of the Modbus library MB_CPCLI and MB_CPSRV
must not be called additionally in an organization block.
A coexistent call of FB MODBUSCP in OB1 and a cyclic interrupt OB, e.g.
OB35 is not permissible.
The OB121 must be available in the CPU. You will find more information
regarding this matter in section “Licensing“.
Start Up of the FB
Cyclical Operation
of the FB
OB121
“Programming
Error”
The function block MODBUSCP should unconditionally be called once in
OB100.
•
The initialization parameters must be set according to the station
configuration.
•
The initialization parameters will be evaluated and copied into the
instance DB.
•
The runtime parameters are not evaluated during start up.
In cyclical operation the FB MODBUSCP is called in OB1 or a cyclic interrupt
OB.
•
According to the runtime parameters, the functions of the function
block are activated.
•
While a request is running changes to the runtime parameters are
ignored.
•
In the cyclical operation initialization parameters are ignored.
If the block has not been licensed yet, the OB121 is called.
Warning
!
The CPU will turn to STOP mode, if the OB121 is not available.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
5-2
Function Block MODBUSCP
Initiate Request
CP is Client
A rising edge at the trigger input ENQ_ENR initiates a request. Depending on
the input parameters UNIT, DATA_TYPE, START_ADDRESS LENGTH and
WRITE_READ a MODBUS request telegram is generated and sent to the
partner station via the TCP/IP connection. The client waits for the
parameterized monitoring time MONITOR for a response from the server.
When the monitoring time elapses (no response from the server) the
activated request is terminated with an error. A new request can be initiated
again.
After the receipt of the response telegram a validity check is carried out. If the
result is positive, necessary actions will be taken and the request will be
terminated without error. The output DONE_NDR is set. When an error is
recognized during verification, the request is terminated with an error, the
ERROR bit is set and an error number is returned in STATUS.
Activation of the
Function Block
CP is Server
With TRUE signal at the trigger input ENQ_ENR the FB is ready for receiving
a request telegram from the client. The server remains passive.
The received telegram is verified. If the telegram is verified positive, the
response telegram is sent. The completed transmission is reported to the
user by setting the DONE_NDR bit.
At this point the completed function is indicated at the outputs UNIT,
DATA_TYPE, START_ADDRESS, LENGTH and WRITE_READ.
A faulty request telegram causes an error message and the ERROR bit is
set. The error number is returned in STATUS. The request of the client is not
answered.
Data Transfer
CPU – CP
The data transfer between CP and CPU are done with the standard function
blocks AG_SEND and AG_RECV respectively AG_LSEND and AG_LRECV.
At the activation of a MODBUS request by the user (CP is client) or at the
receipt of a telegram from the client (CP is server) the standard blocks
necessary for the CP are called by the FB in the right order and number.
At the receipt of a telegram, the first 6 Bytes are read with the function
AG_RECV. This header contains the length of the rest of the telegram. A
second call of the AG_RECV function follows with the rest of the telegram
length. The verification of the received user data takes place after the
complete receipt of the data.
TCP/IP with
CP343-1 / CP443-1
TCP/IP with CP 343-1 and CP443-1 uses static connections. The TCP
connection cannot be disconnected while in run mode.
Given this system characteristic, telegrams might be lost under unfavorable
conditions when the synchronization had been lost after an error.
Termination of the
TCP connection by
the Communication Partner
If the CP acts as server and the communication partner terminates the TCP
connection, the next receive can be started not until an idle time of 1 second
has elapsed.
If the CP acts as Client, the next send can be started not until an idle time of
150 milliseconds has elapsed. This delay, due to system characteristics, is
executed by the function block.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
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5-3
Function Block MODBUSCP
5.2
Parameters of the Function Block MODBUSCP
Parameter
Decl.
Type
Description
id
IN
WORD
Connection-ID as per configuration in NetPro
laddr
IN
WORD
Input-Address of the CP in HW Config
MONITOR
IN
TIME
Monitoring Time: Wait for data from
communication partner
Shortest adjustable time is 20 ms
REG_KEY
IN
STRING Registration key to activate the license
[17]
server_client
IN
BOOL
CP/FB operates in server mode
or client mode (server = slave; client =
master)
single_write
IN
BOOL
Write 1 Coil/Register:
Function code 5 and 6 are used respectively
Function code 15 and 16 are used
respectively
data_type_1
db _1
IN
IN
BYTE
WORD
1st data area: data type
Coils
Inputs
Holding Register
Input Register
1st data area: data block number
Value range
Init
1 to 64
yes
CPU
dependent
yes
T#20ms to
T#+24d20h31
m23s647ms
no
Character
no
TRUE
FALSE
yes
yes
TRUE
FALSE
yes
1
2
3
4
1 to 65535
yes
W#16#1 to
W#16#FFFF
start _1
IN
WORD
1st data area: first Modbus address in this DB
0 to 65535
yes
W#16#0000 to
W#16#FFFF
end _1
IN
WORD
1st data area: last Modbus address in this DB
0 to 65535
yes
W#16#0000 to
W#16#FFFF
data_type_2
IN
BYTE
2nd data area: data type (Coils, Inputs,
Holding Register, Input Register),
NULL if not used
db _2
IN
WORD
2nd data area: data block number
0 to 4
yes
1 to 65535
yes
W#16#1 to
W#16#FFFF
start _2
end _2
IN
IN
WORD
WORD
2nd data area: first Modbus address in this
DB
2nd data area: last Modbus address in this
DB
data_type_3
IN
BYTE
3rd data area: data type (Coils, Inputs,
Holding Register, Input Register),
NULL if not used
db _3
IN
WORD
3rd data area: data block number
0 to 65535
yes
W#16#0000 to
W#16#FFFF
0 to 65535
yes
W#16#0000 to
W#16#FFFF
0 to 4
yes
1 to 65535
yes
W#16#1 to
W#16#FFFF
OPEN MODBUS / TCP communication via CP343-1 and 443-1
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5-4
Function Block MODBUSCP
Parameter
Decl.
Type
Description
start _3
IN
WORD
3rd data area: first Modbus address in this DB
Value range
Init
0 to 65535
yes
W#16#0000 to
W#16#FFFF
end _3
IN
WORD
3rd data area: last Modbus address in this DB
0 to 65535
yes
W#16#0000 to
W#16#FFFF
data_type_4
IN
BYTE
4th data area: data type (Coils, Inputs,
Holding Register, Input Register),
NULL if not used
db _4
IN
WORD
4th data area: data block number
0 to 4
yes
1 to 65535
yes
W#16#1 to
W#16#FFFF
start _4
IN
WORD
4th data area: first Modbus address in this DB
0 to 65535
yes
W#16#0000 to
W#16#FFFF
end _4
IN
WORD
4th data area: last Modbus address in this DB
0 to 65535
yes
W#16#0000 to
W#16#FFFF
data_type_5
IN
BYTE
5th data area: data type (Coils, Inputs,
Holding Register, Input Register),
NULL if not used
db _5
IN
WORD
5th data area: data block number
0 to 4
yes
1 to 65535
yes
W#16#1 to
W#16#FFFF
start _5
IN
WORD
5th data area: first Modbus address in this DB
0 to 65535
yes
W#16#0000 to
W#16#FFFF
end _5
IN
WORD
5th data area: last Modbus address in this DB
0 to 65535
yes
W#16#0000 to
W#16#FFFF
data_type_6
IN
BYTE
6th data area: data type (Coils, Inputs,
Holding Register, Input Register),
NULL if not used
db _6
IN
WORD
6th data area: data block number
0 to 4
yes
1 to 65535
yes
W#16#1 to
W#16#FFFF
start _6
IN
WORD
6th data area: first Modbus address in this DB
0 to 65535
yes
W#16#0000 to
W#16#FFFF
end _6
IN
WORD
6th data area: last Modbus address in this DB
0 to 65535
yes
W#16#0000 to
W#16#FFFF
data_type_7
IN
BYTE
7th data area: data type (Coils, Inputs,
Holding Register, Input Register),
NULL if not used
db _7
IN
WORD
7th data area: data block number
0 to 4
yes
1 to 65535
yes
W#16#1 to
W#16#FFFF
start _7
IN
WORD
7th data area: first Modbus address in this DB
0 to 65535
yes
W#16#0000 to
W#16#FFFF
OPEN MODBUS / TCP communication via CP343-1 and 443-1
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5-5
Function Block MODBUSCP
Parameter
Decl.
Type
Description
end _7
IN
WORD
7th data area: last Modbus address in this DB
Value range
Init
0 to 65535
yes
W#16#0000 to
W#16#FFFF
data_type_8
IN
BYTE
8th data area: data type (Coils, Inputs,
Holding Register, Input Register),
NULL if not used
db _8
IN
WORD
8th data area: data block number
0 to 4
yes
1 to 65535
yes
W#16#1 to
W#16#FFFF
start _8
IN
WORD
8th data area: first Modbus address in this DB
0 to 65535
yes
W#16#0000 to
W#16#FFFF
end _8
IN
WORD
8th data area: last Modbus address in this DB
0 to 65535
yes
W#16#0000 to
W#16#FFFF
ENQ_ENR
IN
BOOL
CP is client: Initiate request at TRUE signal
CP is server: Ready to receive at TRUE signal
TRUE
FALSE
LICENSED
OUT
BOOL
License state of the function block:
Block is licensed
Block is not licensed
TRUE
FALSE
BUSY
OUT
BOOL
Operating state of the functions AG_SEND
and AG_RECV
Job processing
No job processing active
DONE_NDR
OUT
BOOL
CP is client: Active request finished without
errors
CP is server: Request from the client was
executed and answered
ERROR
OUT
BOOL
An error has occurred
No error has occurred
STATUS
OUT
WORD
Error number
STATUS_
FUNC
OUT
no
no
no
TRUE
FALSE
TRUE/FALSE
no
TRUE
FALSE
no
0 to FFFF
no
STRING[ Name of the function, which causes the error
8]
at STATUS
Character
no
IDENT_CODE OUT
STRING[ Identification for licensing
18]
Please order your license with this
identification string.
Character
no
UNIT
IN/
OUT
BYTE
Unit identification (INPUT if in CLIENT mode,
OUTPUT if in SERVER mode)
0 to 255
no
DATA_TYPE
IN/
OUT
BYTE
Data type to be accessed: (INPUT if in
CLIENT mode, OUTPUT if in SERVER mode)
Coils
Inputs
Holding registers
Input registers
START_
ADDRESS
IN/
OUT
WORD
MODBUS start address (INPUT if in CLIENT
mode, OUTPUT if in SERVER mode)
OPEN MODBUS / TCP communication via CP343-1 and 443-1
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no
1
2
3
4
0 to 65535
no
5-6
Function Block MODBUSCP
Parameter
Decl.
Type
Description
LENGTH
IN/
OUT
WORD
Number of registers to be processed
(INPUT if in CLIENT mode, OUTPUT if in
SERVER mode)
Coils: reading function
writing function
Inputs: reading function
Holding Register: reading function
writing function
Input Register: reading function
WRITE_
READ
IN/
OUT
General
Information
BOOL
INPUT if in CLIENT mode, OUTPUT if in
SERVER mode:
Write access
Read access
Value range
Init
no
1 to 2000
1 to 1968
1 to 2000
1 to 125
1 to 123
1 to 125
no
TRUE
FALSE
The parameters of the FB MODBUSCP can be divided into two groups:
•
Initialization parameters
•
Runtime parameters
Initialization parameters are evaluated only during the initial execution of the
function block MODBUSCP and taken over into the instance DB. They are
marked in the above table in the column “INIT“ with “yes“.
A modification of the initialization parameters during run mode has no impact.
After a modification of these parameters (e. g. during the test phase), the
instance DB must be initialized again via a STOP Æ RUN transition of the
CPU.
Runtime parameters can by modified during the cyclical operation. In the
mode “CP is client”, it is not advisable to modify the input parameters while
a request is active. Wait with the next request and the change of the
parameters until the previous request ends with DONE_NDR or ERROR.
In the operation mode “CP is server”, the output parameters may only be
evaluated when DONE_NDR is TRUE.
The output parameters are displayed dynamically, i.e. they are only
available for one PLC cycle. They have to be copied to an additional memory
area if you need to process them or to display the values in a VAT (STEP7
variable table).
Range of Values
For the range of values of the different parameters, CPU specific restrictions
must be taken into consideration.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
5-7
Function Block MODBUSCP
id
For each configured connection in STEP7 (NetPro) a connection ID is
assigned. The connection ID identifies unambiguously the connection from
the CPU via the CP to the communication partner.
The number from the connection configuration has to be entered here.
The range of values for this parameter is 1 to 64.
laddr
The parameter LADDR is the base address of the CP from HW Config (input
address). The configured value has to be entered here.
The range of values for this parameter depends on the CPU.
The parameters ID and LADDR can also be taken from the dialog box
“Properties of TCP Connection”.
MONITOR
The monitoring time MONITOR observes the data input from the
communication partner. The monitoring time can be set in the format T#.... A
monitoring time of approximately 1,5 second is recommended.
In the operating mode “CP is client“ MONITOR specifies the timeout for the
receipt of the complete response telegram from the server. When the
monitoring time elapses, the active request is cancelled with an error. The
timer is started after the completed send of the request telegram and is
stopped after the receipt of the complete data.
In the operating mode “CP is server“ the receipt of the second part of the
telegram is monitored with the MONITOR time. When the time elapses an
error is reported. The timer is started after the receipt of the MODBUS specific
telegram header and is stopped after the receipt of the complete request
telegram.
REG_KEY
The block MODBUSCP must be licensed for each CPU individually to permit
a correct program sequence. With the registration key REG_KEY the block
MODBUSCP is licensed and the Modbus communication runs without any
restraint. You can find further information in section “Licensing”.
server_client
This parameter differentiates the client from the server mode. If the input is
TRUE, then the operating mode is “CP is server“.
If the input is FALSE, then the operating mode is “CP is Client“.
single_write
In operating mode “CP is client” and single_write = TRUE write requests with
length 1 are carried out with the function codes 5 and 6.
With single_write = FALSE all write requests use the function codes 15 and
16.
data_type_x
The parameter data_type_x defines the MODBUS data type which is to be
mapped with this definition.
If data_type_x set to 0, this data area is not used.
Identifier
Data type
Size
0
Area not used
1
Coils
Bit
2
Inputs
Bit
3
Holding Register
Word
4
Input Register
Word
OPEN MODBUS / TCP communication via CP343-1 and 443-1
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5-8
Function Block MODBUSCP
db_x
The parameter db_x defines the number of the data block in which the
consecutively defined MODBUS registers or bits are mapped.
0 cannot be used as DB number since it is reserved for system functions.
db_x
DB-Number
start_x
end_x
1 - 65535 (W#16#0001 to W#16#FFFF)
Start_x specifies the first register or bit address, which is stored in the data
element 0 of the DB. End_x defines the last MODBUS address.
When accessing registers, the number of the data element of the S7 DB in
which the last register is mapped, can be calculated with the following
formula:
DBW number = (end_x – start_x) ∗ 2
When accessing coils or inputs, the number of the data element of the S7 DB
in which the last bit is mapped, can be calculated with the following formula:
DBB number = (end_x – start_x + 7) / 8
The defined memory areas must not overlap. The parameter end_x must not
be smaller than start_x. In case of an error occurring, the initialization of the
FB is stopped with an error. When start_x is equal to end_x, one Modbus
address (1 register or 1 bit) is allocated.
In section 5.3 you can find an example of the mapping of the MODBUS
addresses to S7 memory areas.
ENQ_ENR
Operating mode “CP is client“:
The data transfer is initiated with a TRUE signal at the input. The request
telegram is generated with the values of the input parameters UNIT,
DATA_TYPE, START_ADDRESS, LENGTH and WRITE_READ. A new
request may only be initiated, when the previous one is ended with DONE or
ERROR.
Operating mode “CP is server“:
The FB is activated with a TRUE signal at the input. Telegrams from the client
can be received. With a FALSE signal at the input data is received from the
CP and discarded.
LICENSED
If this output is TRUE, then the Modbus block is licensed on this CPU. If the
output is FALSE, none or a faulty license string was typed in. You can find
further information in section “Licensing”.
BUSY
If this output is TRUE, one of the functions AG_SEND or AG_RECV is
running.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
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5-9
Function Block MODBUSCP
DONE_NDR
In the operating mode “CP is client“ the activated request was executed
without error. For a read function the response data from the server has
already been entered into the DB. For a write function the response to the
request telegram has been received from the server.
In the operating mode “CP is server“ this output indicates a telegram
exchange without errors. In the parameters UNIT, DATA_TYPE,
START_ADDRESS, LENGTH and WRITE_READ the request parameters of
the client are displayed. These outputs are only available and valid as long as
DONE_NDR is TRUE.
ERROR
When this output is set, an error was recognized.
In the operating mode “CP is client“ the activated request was ended with an
error. The error number is displayed in the STATUS output.
In the operating mode “CP is server“ an error is detected at a request
telegram of the client or at sending a response telegram. The error number is
displayed in the STATUS output.
STATUS
The STATUS output displays the error number when ERROR is TRUE. The
error numbers are described in chapter 6.
STATUS_FUNC
This parameter shows the name of the function, which caused the error
occurred.
IDENT_CODE
After start-up of the PLC this parameter displays the identification code, an 18
character string. With this IDENT_CODE you can order the registration key at
IT4industry.
You can find further information in section “Licensing”.
UNIT
In mode “CP is client“ the parameter UNIT is an input parameter. This input
has to be set according to the requirements. The FB copies this value to the
request telegram and verifies when the respond telegram is received.
In mode “CP is server“ the parameter UNIT is an output parameter. The FB
copies this value from the request telegram to the respond telegram. The
output is set with the received value when the job is finished without error.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
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5-10
Function Block MODBUSCP
DATA_TYPE
The parameter DATA_TYPE defines which Modbus data type is to be
accessed with the current job. The following data types are available:
Coils
Inputs
Holding Register
Input Register
B#16#1
B#16#2
B#16#3
B#16#4
In the operating mode “CP is client”, DATA_TYPE is an input parameter. In
the operating mode “CP is server”, DATA_TYPE is an output parameter.
The different data types are related directly to the used function codes.
Data type
START_ADDRESS
DATA_
TYPE
Function
Length
single_
write
Function
code
Coils
1
read
any
irrelevant
1
Coils
1
write
1
TRUE
5
Coils
1
write
1
FALSE
15
Coils
1
write
>1
irrelevant
15
Inputs
2
read
any
irrelevant
2
Holding Register
3
read
any
irrelevant
3
Holding Register
3
write
1
TRUE
6
Holding Register
3
write
1
FALSE
16
Holding Register
3
write
>1
irrelevant
16
Input Register
4
read
any
irrelevant
4
The parameter START_ADDRESS specifies the first MODBUS address that
is read or written.
In the operating mode “CP is client“ it is an input parameter, in the operating
mode “CP is server“ it is an output parameter.
LENGTH
The parameter LENGTH specifies the number of MODBUS registers or bits
that are read or written.
In the operating mode “CP is client“ it is an input parameter. In the operating
mode “CP is server“ it is an output parameter.
For read functions, a maximum of 125 registers or 2000 bits is possible per
telegram. For write functions a maximum of 123 registers or 1968 bits is
possible.
All registers or bits have to be in the same DB per telegram.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
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Function Block MODBUSCP
WRITE_READ
This parameter defines if a read or write function should be carried out. If the
value of the input/output is FALSE, it specifies the read mode. The value
TRUE specifies the write mode.
Only Holding Registers and Coils can be written. Input Registers and Inputs
can be read merely.
In the operating mode “CP is client“ it is an input parameter. In the operating
mode “CP is server“ it is an output parameter.
5.3
Address Mapping
Interpretation of
Modbus
Addresses
MODBUS bases its data model on a series of tables, which have
distinguishing characteristics. The distinction between these memory areas is
done via the register address by some systems, e.g. MODICON PLCs. So a
MODBUS message requesting the read of a holding register at offset 0 would
return the value known to the application programmer as found in register
40001 (memory type 4xxxx, reference 0001).
One potential source of confusion is the varying interpretation of the register
address in different manuals. Sometimes the register address means the
address of the application layer, sometimes the address transferred.
The FB MODBUS uses the Modbus address transferred at its parameters
start_x und START_ADDRESS. So it is possible to use register addresses
from von 0000H to FFFFH with each function code.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
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5-12
Function Block MODBUSCP
Example:
Parameterization
of the Memory
Areas
Address Mapping
data_type_1
db_1
start_1
end_1
data_type_2
db _2
start _2
end _2
data_type_3
db _3
start _3
end _3
data_type_4
db _4
start _4
end _4
data_type_5
db _5
start _5
end _5
data_type_6
db _6
start _6
end _6
data_type_7
db _7
start _7
end _7
data_type_8
db _8
start _8
end _8
B#16#3
W#16#B
W#16#1
W#16#1F4
B#16#3
W#16#C
W#16#2D0
W#16#384
B#16#4
W#16#D
W#16#2D0
W#16#3E8
B#16#0
0
0
0
B#16#1
W#16#E
W#16#280
W#16#4E2
B#16#2
W#16#F
W#16#6A4
W#16#8FC
B#16#1
W#16#10
W#16#6A4
W#16#8FC
B#16#0
0
0
0
Holding Register
DB 11
Start address: 1
End address: 500
Holding Register
DB 12
Start address: 720
End address: 900
Input Register
DB 13
Start address: 720
End address: 1000
Not used
0
0
0
Coils
DB 14
Start address: 640
End address: 1250
Inputs
DB 15
Start address:1700
End address: 2300
Coils
DB 16
Start address: 1700
End address: 2300
Not used
0
0
0
The following diagram shows the comparison of the SIMATIC memory area
and the Modbus typical register oriented storage arrangement. The diagram
is based on the above parameterization.
The Modbus addresses printed in black refer to the Data Link Layer, the ones
printed in grey refer to the Application Layer.
The SIMATIC addresses printed in black are the offset in the DB. You can
find additionally the Modbus register numbers printed in grey.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
5-13
Function Block MODBUSCP
SIMATIC
Modbus device
DB 14
Coils (from 00001)
+ 0.0
640
+ 0.1
641
0
...
...
+76.2
00001
1250
640
00641
641
00642
DB 16
...
+ 0.0
1700
+ 0.1
1701
1250
...
...
1700
+74.7
2299
+75.0
2300
DB 15
+ 0.0
1700
+ 0.1
1701
...
+74.7
2299
+75.0
2300
DB 13
+ 0.0
720
+ 2.0
721
0
1700
11701
1701
11702
...
2300
12301
2301
12302
+ 2.0
2
...
+996.0
499
+998.0
500
DB 12
+ 0.0
720
+ 2.0
721
2301
02302
Input Register
(from 30001)
0
30001
1
30002
...
720
30721
721
30722
...
Holding Register
(from 40001)
1
02301
...
1000
+ 0.0
2300
10001
...
DB 11
01701
...
Inputs (from 10001)
+560.0
01251
0
40001
1
40002
1000
31001
1001
31002
...
499
40500
500
40501
501
40502
...
720
...
40721
...
+358.0
899
900
40901
+360.0
900
901
40902
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
5-14
Function Block MODBUSCP
5.4
Data and Standard Functions used by the FB
Instance DB
The function block MODBUSCP stores its data in an instance DB. This
instance DB is created by STEP7 at the first call of the FB.
The instance data block contains parameters of type Input, Output,
Input/Output as well as static variables that it needs for its execution. These
variables are non-volatile and keep its validity between FB calls. The
variables control the internal process flow of the FB.
Required memory of the instance-DBs:
Instance-DB
work memory
load memory
MODBUSCP
ca. 1kByte
ca. 2kByte
Local Variables
The FB requires 80 Bytes of local variables. Additionally the subordinate FBs
require local variables: FBs MB_CPCLI (30 byte) or MB_CPSRV (30 byte).
V1.x: AG_SEND/AG_RECV or AG_LSEND/AG_LRECV require, up to 58
bytes, depending on the used function block. That gives a maximum of 168
bytes of local data for a FB MODBUSCP V1.x-call.
V2.x: The function AG_CNTRL requires 178 bytes local data. That gives a
maximum of 288 bytes of local data for a FB MODBUSCP V2.x-call.
Timers
The function block does not use any timer.
Flags
The function block does not use any flag.
Standard FCs for
Data Transfer
The function blocks MB_CPCLI and MB_CPSRV respectively called by FB
MODBUSCP use the blocks AG_SEND/AG_RECV (S7-300) and
AG_LSEND/AG_LRECV (S7-400) from the SIMATIC_NET library for the data
transfer between CPU and CP.
The blocks MODCLI and MODSRV version 2.x use the block AG_CNTRL
additionally to reset and reestablish the connection in case of error.
The following versions of the FCs are tested with FB MODBUSCP and
released for the communication:
S7-300:
FC5 “AG_SEND“ version 4.2
FC6 “AG_RECV“ version 4.7
FC10 “AG_CNTRL” version1.0
S7-400
FC50 “AG_LSEND“ version 3.1
FC60 “AG_LRECV“ version 3.1
FC10 “AG_CNTRL” version 1.0
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
5-15
Function Block MODBUSCP
MODBUSCP:
SFCs for
Miscellaneous
Functions
MB_CPCLI and
MB_CPSRV:
SFCs for
Miscellaneous
Functions
The FB MODBUSCP uses the following SFBs/SFCs from the standard library:
•
SFB4 „TON“
•
SFC6 „RD_SINFO“
•
SFC20 „BLKMOV“
•
SFC51 „RDSYST”
•
SFC52 „WR_USMSG
The FBs MB_CPCLI and MB_CPSRV use the following SFCs from the
standard library:
•
SFC20 „BLKMOV“
•
SFC24 „TEST_DB”
•
SFB4 „TON“
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
5-16
Function Block MODBUSCP
5.5
Renaming of Standard Functions
Inducement
Whether you have already used the numbers of standard functions in your
project or the block number is reserved for a different application, you may
rename the internal called functions FC5/FC50 or FC6/FC60, FC10 or the
blocks MODBUSCP, MB_CPCLI and MB_CPSRV.
It is not possible to rename the system functions SFC6, SFC20, SFC24,
SFC51 and SFC52 as well as the system function block SFB4.
Behavior
A set of rules concerning the function block numbering have to be considered
when rewiring function blocks in SIMATIC STEP 7 Manager.
If you want to rewire the blocks of the Modbus library, the following sequence
is required:
1. FC50 AG_LSEND
FC60 AG_LRECV
2. FB106 MB_CPCLI
FB107 MB_CPSRV
3. FB108 MODBUSCP
It is not necessary to rewire all blocks. Even if you want to rewire only some of
the blocks, you must follow the mentioned sequence.
Renaming
To rename the blocks proceed as described subsequently:
1. Get the information about the used operand by clicking "Extras >
Reference data > Display".
2. Set the operand priority in the object properties of the block folder to
"Absolute value".
3. Call the function "Extras > Re-wire" in the SIMATIC Manager, in order
to re-wire the operands into free areas.
4. To be able to keep on using the symbolism diagnostics tools, add the
modifications in the symbolism table supplementary.
The modifications can be verified by clicking "Extras > Reference data >
Display".
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
5-17
Diagnostics
6
Diagnostics
Diagnostic
Function
The diagnostic functions of the CP 343/ CP 443 allow you fast failure
localization. The following diagnostic features are available:
• Diagnostics via the display elements of the CP
• Diagnostics via the STATUS output of the function block MODBUSCP.
Display Elements
(LED)
The display elements inform you about the operating mode or about the
failure conditions of the CP. The display elements give you an overview of
internal failures, external failures and interface specific failures.
STATUS Output of
the FB
MODBUSCP
For error diagnostics, the function block MODBUSCP has got a STATUS
output. By reading the STATUS output you get a general indication of failures
that have occurred during the communication. The STATUS parameter can
be evaluated in the user program.
The output STATUS_FUNC shows the name of the function, which has
caused the error.
6.1
Diagnostics via the Display Elements of the CP
Display Functions
The display elements of the CP give you information on the module status.
There are two types of display functions:
•
Group Error Displays
- INTF Internal failure
- EXTF External failure
•
Special Displays
CP 343-1:
- RX/TX
A telegram is being transmitted via the interface.
CP 443-1:
- TXD
A telegram is being sent via the interface.
- RXD
A telegram is being received via the interface.
A detailed description of the display elements can be found in the device
manual of the CP.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
6-1
Diagnostics
6.2
Diagnostic Messages of the FB MODBUSCP
Messages at the
STATUS Output of
the FB
The block MOBUSCP has got 2 status outputs: STATUS and
STATUS_FUNC. STATUS displays all error numbers. STATUS_FUNC shows
the name of the function, which caused the error. STATUS is valid when
ERROR is TRUE. Below you can find a list of FB-specific error messages.
Error Messages of
the called SFCs
and FCs
The FB MODBUSCP, MB_CPCLI and MB_CPSRV use the standard
functions SFC6, SFC20, SFC24, SFC51, SFC52, FC5 and FC6, or FC50 and
FC60. The error messages of these blocks are passed on to STATUS without
any changes.
In the diagnostics buffer or in the online help of SIMATIC Manager you will
find further details on these error messages, as well as in the SIMATIC
STEP7 NCM S7 Industrial Ethernet Manual.
Error messages of FB MODBUSCP
STATUS Event text
Remedy
(Hex)
A002
The parameter end_x is less than start_x.
Correct the parameterization of
start_x and end_x
A003
The DB, to which MODBUS addresses shall be
mapped, is too short.
Minimum length:
registers: ( end_x – start_x + 1 ) ∗ 2
bits: ( end_x - start_x ) / 8 + 1
Extend the DB.
CP is Client: Correct the
parameters START_ADDRESS
or LENGTH
Other possible reasons:
CP is Server:
Modify the request of the client.
•
Wrong initialization parameter (CP is client).
•
Wrong address area in the request telegram of
the client (CP is server). The CP sends an
exception telegram.
A004
Applies only with CP is client:
An invalid combination of DATA_TYPE and
WRITE_READ is given.
Correct the parameters. Only
data type 1 or 3 can be written.
A005
CP is client:
An invalid value for the parameter LENGTH is given.
CP is Client:
Correct the parameter LENGTH.
CP is Server:
The number of registers/bits in the request telegram is
invalid. The CP sends an exception telegram.
CP is Server:
Modify the number of
registers/bits in the request
telegram.
Range of values:
Read coils/inputs: 1 to 2000
Write coils: 1 to 1968
Read registers: 1 to 125
Write holding registers: 1 to 123
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
6-2
Diagnostics
Error messages FB MODBUSCP
STATUS Event text
Remedy
(Hex)
A006
The given range of data defined with DATA_TYPE,
START_ADDRESS and LENGTH does not exist in
data_type_1 to data_type_8.
CP is server:
The CP sends an exception telegram.
CP is Client:
Correct the parameter’s
combination DATA_TYPE,
START_ADDRESS and
LENGTH.
CP is Server:
Modify the request of the client
or correct the parameterization
of data_type_x.
A007
CP is client:
An invalid monitoring time MONITOR is parameterized.
A value > 20ms is required.
Correct the parameterization.
A008
Monitoring time MONITOR elapsed when AG_RECV
waits for receipt. E.g. Partner is not ready.
Verify error messages at the
communication partner.
MODBUSCP V2.x:
Check if the communication
All connections via Port 502 are terminated and
partner needs a special unit
reestablished.
identifier.
MODBUSCP V1.x:
As an after effect the loss of synchronization can occur,
which leads to a loss of telegrams.
A009
CP is client: The received transaction identifier TI is not
equal to the sent one.
MODBUSCP V2.x:
All connections via Port 502 are terminated and
reestablished.
A00A
CP is client: The received UNIT is not equal to the sent
one.
MODBUSCP V2.x:
All connections via Port 502 are terminated and
reestablished.
A00B
CP is client:
Received function code is not equal to the sent one.
CP is server:
An invalid function code was received. The CP sends
an exception telegram.
MODBUSCP V2.x:
All connections via Port 502 are terminated and
reestablished.
MODBUSCP V1.x:
As an after effect the loss of synchronization can occur,
which leads to a loss of telegrams.
A00C
The received byte count does not match the number of
registers/bits.
CP is server: The CP sends an exception telegram.
MODBUSCP V2.x:
All connections via Port 502 are terminated and
reestablished.
A00D
Only when CP is client: The register/bit address or the
number of registers/bits in the response telegram is not
equal to the one in the request telegram.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
Verify the data of the
communication partner with the
help of a telegram trace.
CP is client:
Verify the data of the
communication partner with the
help of a telegram trace.
CP is server:
The FB MODBUSCP supports
the function codes 1, 2, 3, 4, 5,
6, 15 and 16.
Verify the data of the
communication partner with the
help of a telegram trace.
6-3
Diagnostics
Error messages the FB MODBUSCP
STATUS Event text
Remedy
(Hex)
A00E
The length indicated in the MODBUS specific telegram Verify the data of the
communication partner with the
header does not match the number of registers/bits or
the byte count in the telegram. The FB receives all data help of a telegram trace.
and ignores them.
MODBUSCP V2.x:
All connections via Port 502 are terminated and
reestablished.
MODBUSCP V1.x:
As an after effect a loss of synchronization might occur.
A00F
A protocol identifier <> 0 was received.
MODBUSCP V2.x:
All connections via Port 502 are terminated and
reestablished.
MODBUSCP V1.x:
As an after effect a loss of synchronization might occur.
A010
In the parameterized area db_1 to db_8 a DB number is Correct the parameterization of
used twice.
db_x.
A011
An invalid value for DATA_TYPE is given (Value range: Correct the parameters.
1 to 4).
A012
The parameterized areas data_type_1 and data_type_2 Correct the parameterization.
overlap.
The data areas must not contain
The parameterized areas data_type_1 and data_type_3 any overlapping register areas.
overlap.
A013
A014
The parameterized areas data_type_1 and data_type_4
overlap.
A015
The parameterized areas data_type_1 and data_type_5
overlap.
A016
The parameterized areas data_type_1 and data_type_6
overlap.
A017
The parameterized areas data_type_1 and data_type_7
overlap.
A018
The parameterized areas data_type_1 and data_type_8
overlap.
A019
0 is assigned to one of the parameters db_x while the
according data_type_x is <> 0.
DB 0 can’t be used; it is reserved for system functions.
Correct the parameterization of
db_x to > 0.
A01A
Wrong length in header:
Range of values: 3 to 253 bytes.
Verify the data of the
communication partner with the
help of a telegram trace.
MODBUSCP V2.x:
All connections via Port 502 are terminated and
reestablished.
A01B
CP is server and function code 5:
An invalid value for coils was received.
The CP sends an exception telegram.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
6-4
Diagnostics
Error messages of FB MODBUSCP
STATUS Event text
Remedy
(Hex)
A01E
The CP has received invalid data which could not be
assigned.
MODBUSCP V2.x:
All connections via Port 502 are terminated and
reestablished.
MODBUSCP V1.x
The CP has lost synchronization and needs data from
the communication partner to finish the active
AG_RECV.
Check the error message of the
communication partner and verify
the data with a telegram trace if
needed.
A01F
The FB MODBUSCP has turned to an invalid state.
Please contact the product
support.
A023
The parameterized areas data_type_2 and
data_type_3 overlap.
Correct the parameterization.
A024
The parameterized areas data_type_2 and
data_type_4 overlap.
A025
The parameterized areas data_type_2 and
data_type_5 overlap.
A026
The parameterized areas data_type_2 and
data_type_6 overlap.
A027
The parameterized areas data_type_2 and
data_type_7 overlap.
A028
The parameterized areas data_type_2 and
data_type_8 overlap.
A034
The parameterized areas data_type_3 and
data_type_4 overlap.
A035
The parameterized areas data_type_3 and
data_type_5 overlap.
A036
The parameterized areas data_type_3 and
data_type_6 overlap.
A037
The parameterized areas data_type_3 and
data_type_7 overlap.
A038
The parameterized areas data_type_3 and
data_type_8 overlap.
A045
The parameterized areas data_type_4 and
data_type_5 overlap.
A046
The parameterized areas data_type_4 and
data_type_6 overlap.
A047
The parameterized areas data_type_4 and
data_type_7 overlap.
A048
The parameterized areas data_type_4 and
data_type_8 overlap.
A056
The parameterized areas data_type_5 and
data_type_6 overlap.
A057
The parameterized areas data_type_5 and
data_type_7 overlap.
A058
The parameterized areas data_type_5 and
data_type_8 overlap.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
The data areas must not contain
any overlapping register areas.
6-5
Diagnostics
Error messages of FB MODBUSCP
STATUS Event text
Remedy
(Hex)
A067
The parameterized areas data_type_6 and
data_type_7 overlap.
A068
The parameterized areas data_type_6 and
data_type_8 overlap.
A078
The parameterized areas data_type_7 and
data_type_8 overlap.
A07A
An invalid value id is parameterized. Range of values is Correct the parameterization of
1 to 64.
the input id.
A07C
An invalid value data_type_x was given. The value
range is 0 to 4.
Correct the parameterization of
data_type_x.
A07D
Parameter data_type_1 is not defined. The parameter
area _1 is the default area and must be defined.
Correct the parameterization of
data_type_1.
A07E
The DB number of db_x is identical to the number of
the instance DB.
Correct the parameterization of
db_x.
A080
Different instance DBs were used for the call of
MODBUSCP in OB100 and the cyclic OB.
MODBUSCP must be called with
the identical instance DB in
OB100 and the cyclic OB.
A081
Only if CP is client and function code 5:
The received coil status is not equal to the sent one.
Verify the data of the
communication partner with the
help of a telegram trace.
A082
Only if CP is client and function code 6:
Verify the data of the
The received register value is not equal to the sent one. communication partner with the
help of a telegram trace.
A083
Only if CP is client:
A request was initiated prior to the completion of the
previous one. The request is not executed.
A085
An error occurred during the license handling due to an Verify the project if there is any
invalid write access.
invalid write access to the license
DB. The structure of REG_KEY
must not be changed. Please
contact the Product Support if
necessary.
A090
The block MODBUSCP is not licensed for this CPU.
This is a status information. The bit ERROR is not set.
The Modbus communication runs without a license as
well.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
Correct the parameterization.
The data areas must not contain
any overlapping register areas.
Wait with the initiation of a new
request until the previous one
was finished either with
DONE/NDR = TRUE or ERROR
= TRUE.
Read the identification string
IDENT_CODE for this CPU and
order the registration key at
IT4industry.
See also section “Licensing”.
6-6
Diagnostics
Error messages of FB MODBUSCP
STATUS Event text
Remedy
(Hex)
A091
An exception telegram with exception code 1 was
received (only if CP is client)
The communication partner does
not support the requested
function.
A092
An exception telegram with exception code 2 was
received (only if CP is client)
Correct LENGTH or
START_ADDRESS at the call of
the FB.
An attempt to an invalid or non existing address at the
communication partner was made.
A093
An exception telegram with exception code 3 was
received (only if CP is client)
The communication partner can’t
process the received request
(e.g. doesn’t support the
requested length).
A094
An exception telegram with exception code 4 was
received (only if CP is client)
The communication partner is in
a state, in which the received
request can’t be processed.
A095
An exception telegram with an unknown exception
code was received (only if CP is client).
Check the error message of the
communication partner and verify
the data with a telegram trace if
needed.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
6-7
Diagnostics
6.3
Diagnostic Messages of FC5/FC6 and FC50/FC60
Diagnostic messages of the included blocks AG_SEND/AG_RECV (FC5/FC6) and
AG_LSEND/AG_LRECV (FC50/FC60) at the output STATUS
STATUS Event text
Remedy
(Hex)
6.4
7xxx
For detailed information please refer to the online help
of SIMATIC Manager.
See online help (SIMATIC
manager -> mark block -> key F1
–> Ethernet -> see also -> code
evaluation )
8xxx
For detailed information please refer to the online help
of SIMATIC Manager.
See online help (SIMATIC
manager -> mark block -> key F1
–> Ethernet -> see also -> code
evaluation )
Diagnostic Messages of included FCs/SFCs
Diagnostic messages of the included blocks RD_SINFO (SFC6), BLKMOV (SFC20) , SFC51
(RDSYSST), SFC52 (WR_USMSG) and AG_CNTRL at the output STATUS
STATUS Event text
Remedy
(Hex)
6.5
7xxx
For detailed information please refer to the online help
of SIMATIC Manager.
See online help (SIMATIC
manager -> mark block -> key F1)
8xxx
For detailed information please refer to the online help
of SIMATIC Manager.
See online help (SIMATIC
manager -> mark block -> key F1)
Diagnostic Messages of SFC24
Error messages of SFC24
STATUS Event text
Remedy
(Hex)
80A1
DB Number = 0 or too large for the CPU
Choose a valid DB number.
80B1
The DB does not exist in the CPU.
All data blocks that are specified
in db_x must be created and
copied into the CPU.
80B2
DB UNLINKED
DB must not be created as
UNLINKED.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
6-8
Application Sample
7
Application Samples
General
Information
With the installation 2 sample projects are installed in \Program
Files\Siemens\Step7\Examples.
•
sample project “MB_TCP_CP” written in STL and
•
sample project “MB_TCP_CP_CFC” written in CFC
The S7 programs are for information purposes only and are not to be
understood as a solution for a customer specific installation configuration.
Programming
Example
The programming examples consist of the blocks:
• Start-Up OB100
• Programming error OB121
• Cyclic program processing OB1 and OB35 respectively with call of FB 108
• Global DB for job trigger (e.g. via a variable table) and for licensing
• Data blocks for register values
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
7-1
Application Sample
7.1
Sample project STL
General
Information
Used Blocks
The sample project written in STL includes serveral Simatic stations for the
different applications.
•
Simatic Station is S7-300 or S7-400
•
Simatic Station is client or server
•
Simatic Station supports or doesn’t support AG_CNTRL
The subsequent listed blocks are used in the provided example project for S7
stations with FB MODBUSCP.
Block
Symbol
Comment
OB 1
CYCL_EXC
Cyclic program processing
OB 100
COMPLETE
RESTART
Start-Up OB for Re-Start
OB 121
PROG_ERR
Programming error OB
FB 108
MODBUSCP
User block FB MODBUSCP
FB 106
MB_CPCLI
Internally called FB MB_CPCLI
FB 107
MB_CPSRV
Internally called FB MB_CPSRV
DB 1
CONTROL_DAT
Work-DB CONTROL DAT for FB MODBUSCP
DB 3
LICENSE_DB
License DB for FB MODBUSCP
DB 11
DATA_AREA_1
Value DB for area 1
DB 12
DATA_AREA_2
Value DB for area 2
DB 13
DATA_AREA_3
Value DB for area 3
DB 14
DATA_AREA_5
Value DB for area 5
DB 15
DATA_AREA_6
Value DB for area 6
DB 16
DATA_AREA_7
Value DB for area 7
DB 108
IDB_MODBUS
Instance DB for FB MODBUSCP
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
7-2
Application Sample
7.2
Sample project CFC
General
Information
The sample project written in CFC includes two Simatic S7-400 stations, one
is parameterized as client, the other one as server.
Used Blocks
The subsequent listed blocks are used in the provided example project with
FB MODBUSCP. The system functions, system function blocks and the
blocks which are generated by CFC are not listed in the following table.
Block
Symbol
Comment
OB 35
CYC_INT5
Cyclic program processing
OB 100
COMPLETE
RESTART
Start-Up OB for Re-Start
OB 121
PROG_ERR
Programming error OB
FB 8
R_TRIG
Recognition of positive edge
FB 24
CTU
Upwards counter
FB 99
Save_STATUS
FB to save the error number and the name of the
according function
FB 106
MB_CPCLI
Internally called FB MB_CPCLI
FB 107
MB_CPSRV
Internally called FB MB_CPSRV
FB 108
MODBUSCP
User block FB MODBUSCP
FC 500
AG_LSEND
FC to send data
FC 600
AG_LRECV
FC to receive data
DB1
MEMORY_DB
Help DB in server mode
DB 3
LICENSE_DB
License DB for FB MODBUSCP
DB 11
DATA_AREA_1
Value DB for area 1
DB 12
DATA_AREA_2
Value DB for area 2
DB 13
DATA_AREA_3
Value DB for area 3
DB 14
DATA_AREA_5
Value DB for area 5
DB 15
DATA_AREA_6
Value DB for area 6
DB 16
DATA_AREA_7
Value DB for area 7
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
7-3
A Literature
MODBUS IDA
MODBUS APPLICATION PROTOCOL SPECIFICATION
V1.1b, December 28, 2006
http://www.modbus-IDA.org
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
Appendix - 1
Customer Support
Siemens AG
Industry Sector
I IS IN OC
Werner-von-Siemens-Str. 60
91052 Erlangen
Tel: ++49 9131 7-46111
Fax: ++49 9131 7-44757
Mail: it4.industry@siemens.com
http://www.siemens.com/s7modbus
Siemens Aktiengesellschaft
Subject to change without prior notice.
OPEN MODBUS / TCP communication via CP343-1 and 443-1
2XV9450-1MB00; Manual edition 4.3
Stand: 06/2011