Siemens SIMATIC NET S7-1500 User manual

SIMATIC CM 1542-1
SIMATIC NET
S7-1500 - PROFINET
SIMATIC CM 1542
-1
Operating Instructions
CM 1542-1, firmware V3.0 (6GK7542-1AX00-0XE0)
CM 1542
-1, firmware V4.0 (6GK7542-1AX10-0XE0)
04/2023
C79000
-G8976-C355-05
Preface
Properties and functions
1
LEDs
2
Installation, connecting up,
commissioning, operation
3
Configuration, program
blocks
4
Diagnostics and upkeep
5
Technical specifications
6
Approvals
7
Dimension drawings
8
Documentation references
A

Siemens AG
Digital Industries
Postfach 48 48
90026 NÜRNBERG
GERMANY
C79000-G8976-C355-05
Ⓟ
03/2023 Subject to change
Copyright © Siemens AG 2014 - 2023.
All rights reserved
Legal information
Warning notice system
This manual contains notices you have to observe in order to ensure your personal safety, as well as to prevent
damage to property. The notices referring to your personal safety are highlighted in the manual by a safety alert
symbol, notices referring only to property damage have no safety alert symbol. These notices shown below are
graded according to the degree of danger.
DANGER
indicates that death or severe personal injury will result if proper precautions are not taken.
WARNING
indicates that death or severe personal injury may result if proper precautions are not taken.
CAUTION
indicates that minor personal injury can result if proper precautions are not taken.
NOTICE
indicates that property damage can result if proper precautions are not taken.
If more than one degree of danger is present, the warning notice representing the highest degree of danger will
be used. A notice warning of injury to persons with a safety alert symbol may also include a warning relating to
property damage.
Qualified Personnel
The product/system described in this documentation may be operated only by personnel qualified for the specific
task in accordance with the relevant documentation, in particular its warning notices and safety instructions.
Qualified personnel are those who, based on their training and experience, are capable of identifying risks and
avoiding potential hazards when working with these products/systems.
Proper use of Siemens products
Note the following:
WARNING
Siemens products may only be used for the applications described in the catalog and in the relevant technical
documentation. If products and components from other manufacturers are used, these must be recommended
or approved by Siemens. Proper transport, storage, installation, assembly, commissioning, operation and
maintenance are required to ensure that the products operate safely and without any problems. The permissible
ambient conditions must be complied with. The information in the relevant documentation must be observed.
Trademarks
All names identified by ® are registered trademarks of Siemens AG. The remaining trademarks in this publication
may be trademarks whose use by third parties for their own purposes could violate the rights of the owner.
Disclaimer of Liability
We have reviewed the contents of this publication to ensure consistency with the hardware and software
described. Since variance cannot be precluded entirely, we cannot guarantee full consistency. However, the
information in this publication is reviewed regularly and any necessary corrections are included in subsequent
editions.

SIMATIC CM 1542-1
Operating Instructions, 04/2023, C79000-G8976-C355-05 3
Preface
Validity of this manual
This document contains information on the following products:
•Communications module CM 1542-1
Article number 6GK7 542-1AX00-0XE0
Hardware product version 1
Firmware version V3.0
•Communications module CM 1542-1
Article number 6GK7 542-1AX10-0XE0
Hardware product version 1
Firmware version V4.0
Communications modules for connecting S7-1500 to PROFINET
View of the CM
①
LEDs for status and error displays
②
LED display of the Ethernet ports X1 P1 and X1 P2
③
Type plate
④
PROFINET interface: 2 x 8-pin RJ45 jack
⑤
Label with MAC address
Figure 1 View of the CM 1542-1 with closed (left) and open (right) front cover

Preface
SIMATIC CM 1542-1
4Operating Instructions, 04/2023, C79000-G8976-C355-05
Abbreviations and reference to the module version
•CM / module / device
These terms are used in the following instead of the complete product designation. In this
case, the information applies equally to both firmware versions or hardware product
versions of the module.
If the data of the two devices differs, the firmware version or the hardware version of the
respective device is explicitly stated.
•STEP 7
The name STEP 7 is used to mean the STEP 7 Professional configuration tool.
Address label: Unique MAC address preset for the CM
When supplied, the CM has a total of 3 default MAC addresses with the following assignment:
•PROFINET interface
The MAC address of the PROFINET interface is printed on the enclosure.
(Visible in STEP 7 for "Accessible devices")
•One MAC address for each of the 2 Ethernet ports of the PROFINET interface
The MAC addresses of the Ethernet ports are required only for detection and evaluation of
neighborhood and topology relations (LLDP).
Purpose of the manual
This manual supplements the S7-1500 system manual.
With the information in this manual and the system manual, you will be able to commission
the CM.
New in this edition
•New module with new article number, see above.
•New firmware versions, with the following functions among others:
–Safety-related product improvements, see section Security information (Page 13).
–CM 1542-1 (6GK7 542-1AX10-0XE0, firmware version V4.0):
Enabling/disabling SNMP via data record; see section Disabling SNMP via data record
(Page 42).
•New approvals: CCC / UKEX
•Editorial revision
Replaced edition
Edition 07/2019

Preface
SIMATIC CM 1542-1
Operating Instructions, 04/2023, C79000-G8976-C355-05 5
Manual on DVD
You will find the manual on the DVD supplied with the product. This DVD contains the
product manuals valid at the time it is created.
Current manual edition on the Internet
You will also find the current version of this manual on the Internet pages of Siemens
Automation Customer Support:
Link: (https://support.industry.siemens.com/cs/ww/en/ps/15341/man)
License conditions
Note
Open
source software
The product contains open source software. Read the license conditions for open source
software carefully before using the product.
You will find license conditions in the following document on the supplied data medium:
•OSS_CM15421_86.pdf
•OSS_CM15421_99.pdf
Security information
Siemens provides products and solutions with industrial security functions that support the
secure operation of plants, systems, machines and networks.
In order to protect plants, systems, machines and networks against cyber threats, it is
necessary to implement – and continuously maintain – a holistic, state-of-the-art industrial
security concept. Siemens’ products and solutions constitute one element of such a concept.
Customers are responsible for preventing unauthorized access to their plants, systems,
machines and networks. Such systems, machines and components should only be connected
to an enterprise network or the internet if and to the extent such a connection is necessary
and only when appropriate security measures (e.g. firewalls and/or network segmentation)
are in place.
For additional information on industrial security measures that may be implemented, please
visit
Link: (http://www.siemens.com/industrialsecurity)
Siemens’ products and solutions undergo continuous development to make them more
secure. Siemens strongly recommends that product updates are applied as soon as they are
available and that the latest product versions are used. Use of product versions that are no
longer supported, and failure to apply the latest updates may increase customers’ exposure to
cyber threats.
To stay informed about product updates, subscribe to the Siemens Industrial Security RSS
Feed under
Link: (https://www.siemens.com/cert)

Preface
SIMATIC CM 1542-1
6Operating Instructions, 04/2023, C79000-G8976-C355-05
Firmware
The firmware is signed and encrypted. This ensures that only firmware created by Siemens
can be downloaded to the device.
Note on firmware/software support
Check regularly for new firmware/software versions or security updates and apply them. After
the release of a new version, previous versions are no longer supported and are not
maintained.
Documentation guide
The documentation of the SIMATIC products has a modular structure and covers topics
relating to your automation system.
The complete documentation for the S7-1500 system consists of a system manual, function
manuals and device manuals.
The STEP 7 information system (online help) also supports you in configuring and
programming your automation system.
Overview of the documentation on communication with S7-1500
The following table lists additional documents, which supplement this description of the
CM 1542-1. The documents are available on the Internet.
Table 1 Documentation for the S7-1500 system
Topic
Documentation
Important contents
System
description
S7-1500 automation system
(https://support.industry.siemens.com/cs/ww/e
n/view/59191792) system manual
•Application planning
•Installation
•Connecting
•Commissioning
Module properties Power supplies
(https://support.industry.siemens.com/cs/ww/e
n/ps/13743/man) manual
•Connecting
•Parameter assignment,
addressing
•Interrupts, error messages,
diagnostics and system
alarms
•Technical specifications
•Dimension drawing
Signal modules
(https://support.industry.siemens.com/cs/ww/e
n/ps/13721/man) manual
System
diagnostics
System diagnostics
(https://support.industry.siemens.com/cs/ww/e
n/view/59192926) function manual
•Overview
•Diagnostics evaluation for
hardware/software
Communication
Communication
(https://support.industry.siemens.com/cs/ww/e
n/view/59192925) function manual
•Overview

Preface
SIMATIC CM 1542-1
Operating Instructions, 04/2023, C79000-G8976-C355-05 7
Topic
Documentation
Important contents
Function manual PROFINET with STEP 7
•PROFINET basics
•PROFINET functions
•PROFINET diagnostics
Web server
(https://support.industry.siemens.com/cs/ww/e
n/view/59193560) function manual
•Function
•Operation
Interference-free
installation of
control systems
Designing interference-free controllers
(https://support.industry.siemens.com/cs/ww/e
n/view/59193566) function manual
•Basics
•Electromagnetic
compatibility
•Lightning protection
•Housing selection
Memory concept Structure and Use of the CPU Memory
(https://support.industry.siemens.com/cs/ww/e
n/view/49948856) function manual
•Design
•Principle of operation
•Use
Cycle and
response times Function manual: Cycle and Response Times (https://support.industry.siemens.com/cs/ww/e
n/view/59193558)
•Basics
•Calculations
Analog value
processing
Function manual: Analog value processing
(https://support.industry.siemens.com/cs/ww/e
n/view/67989094)
•Wiring options
•Tables of measured values
Table 2 Documentation on Industrial Ethernet / PROFINET
Topic
Documentation
Important contents
Industrial Ethernet /
PROFINET
SIMATIC NET
Industrial Ethernet / PROFINET
System manual
•Industrial Ethernet
Link:
(https://support.industry.siemens.com/c
s/ww/de/view/27069465)
•Passive network components
Link:
(https://support.industry.siemens.com/c
s/ww/en/view/84922825)
•Ethernet/PROFINET
networks
•Network configuration
•Network components
You will find additional documents on the Siemens Industry Online Support pages in the
appendix Documentation references (Page 65).
FAQs on the Internet
You will find detailed information (FAQs) on using the CM described here on the Internet at
the following address (entry type "FAQ"):
Link: (https://support.industry.siemens.com/cs/ww/en/ps/15341/faq)

Preface
SIMATIC CM 1542-1
8Operating Instructions, 04/2023, C79000-G8976-C355-05
SIMATIC NET glossary
The SIMATIC NET glossary describes terms that may be used in this document.
You will find the SIMATIC NET glossary in the Siemens Industry Online Support at the
following address:
Link: (https://support.industry.siemens.com/cs/ww/en/view/50305045)
Device defective
If a fault develops, please send the device to your Siemens representative for repair. Repairs
on-site are not possible.
Decommissioning
Shut down the device properly to prevent unauthorized persons from accessing confidential
data in the device memory.
Recycling and disposal
The product is low in pollutants, can be recycled and meets the requirements of the WEEE
directive 2012/19/EU "Waste Electrical and Electronic Equipment".
Do not dispose of the product at public disposal sites. For environmentally friendly recycling
and the disposal of your old device contact a certified disposal company for electronic scrap
or your Siemens contact.
Keep to the local regulations.
You will find information on returning the product on the Internet pages of Siemens Industry
Online Support:
Link: (https://support.industry.siemens.com/cs/ww/en/view/109479891)

SIMATIC CM 1542-1
Operating Instructions, 04/2023, C79000-G8976-C355-05 9
Table of contents
Preface ................................................................................................................................................... 3
1 Properties and functions...................................................................................................................... 11
1.1 Communication services .................................................................................................... 11
1.2 Further functions............................................................................................................... 11
1.3 Security information .......................................................................................................... 13
1.4 Intended operating environment........................................................................................ 14
1.5 Configuration limits and performance data......................................................................... 15
1.5.1 Transmission and reaction times ........................................................................................ 15
1.5.2 Connection resources......................................................................................................... 15
1.5.3 Characteristic data Open User Communication incl. e-mail.................................................. 16
1.5.4 Characteristics of S7 communication.................................................................................. 18
1.5.5 PROFINET IO characteristic data.......................................................................................... 18
1.5.6 Rack components............................................................................................................... 19
1.6 Requirements for use......................................................................................................... 19
1.6.1 Usable CPUs....................................................................................................................... 19
1.6.2 Project engineering............................................................................................................ 20
1.6.3 Program blocks.................................................................................................................. 21
2 LEDs ..................................................................................................................................................... 23
3 Installation, connecting up, commissioning, operation...................................................................... 25
3.1 Important notes on using the device .................................................................................. 25
3.1.1 Notices on use in hazardous areas...................................................................................... 25
3.1.2 Notes on use in hazardous areas according to ATEX / UKEX / IECEx / CCC-Ex ........................ 25
3.1.3 Notes on use in hazardous areas according to UL HazLoc and FM........................................ 26
3.2 Installation, removal and repairs in hazardous areas ........................................................... 27
3.3 Installation......................................................................................................................... 28
3.4 Connecting........................................................................................................................ 32
3.5 Mode of the CPU - effect on the CM.................................................................................... 33
3.6 Disassembly....................................................................................................................... 33
4 Configuration, program blocks............................................................................................................ 35
4.1 Security recommendations................................................................................................. 35
4.2 Network settings................................................................................................................ 38
4.2.1 Fast Ethernet ..................................................................................................................... 38
4.3 IP configuration ................................................................................................................. 38
4.3.1 Restart after detection of a duplicate IP address in the network........................................... 38
4.3.2 Remove retentive storage of the IP address if there are duplicate addresses ........................ 38
4.3.3 IP routing........................................................................................................................... 39
4.3.4 CM in multiple use IO systems (standard machines)............................................................ 40

Table of contents
SIMATIC CM 1542-1
10 Operating Instructions, 04/2023, C79000-G8976-C355-05
4.4 Media redundancy............................................................................................................. 41
4.5 Time-of-day synchronization.............................................................................................. 41
4.6 Disabling SNMP via data record .......................................................................................... 42
4.7 Program blocks for OUC..................................................................................................... 43
5 Diagnostics and upkeep ...................................................................................................................... 47
5.1 Diagnostics........................................................................................................................ 47
5.1.1 Diagnostics options............................................................................................................ 47
5.1.2 SNMP ................................................................................................................................ 47
5.2 Maintenance ..................................................................................................................... 49
5.2.1 Update firmware................................................................................................................ 50
5.2.2 Module replacement.......................................................................................................... 52
6 Technical specifications....................................................................................................................... 53
6.1 Technical specifications of the CM (6GK7542-1AX00-0XE0)................................................ 53
6.2 Technical specifications of the CM (6GK7542-1AX10-0XE0)................................................ 54
6.3 Terminal assignment ......................................................................................................... 55
6.4 Permitted cable lengths - Ethernet ..................................................................................... 55
6.5 Ambient temperature ........................................................................................................ 56
7 Approvals............................................................................................................................................. 57
8 Dimension drawings............................................................................................................................ 63
A Documentation references.................................................................................................................. 65
Index.................................................................................................................................................... 69

SIMATIC CM 1542-1
Operating Instructions, 04/2023, C79000-G8976-C355-05 11
Properties and functions
1
1.1 Communication services
The CM supports the following communications services:
•PROFINET IO
PROFINET IO allows direct access to IO devices over Industrial Ethernet.
–Real-Time communication (RT)
–Isochronous Real-Time communication (IRT)
–Media redundancy MRP
–Device replacement without exchangeable storage medium
–IO controller
–IO device (iDevice, Shared Device, Prioritized startup)
–Isochronous real time
•Open User Communication
Open User Communication supports the following communications services via the CM
using programmed or configured communications connections:
–TCP (complying with RFC 793), ISO-on-TCP (complying with RFC 1006) and UDP
(complying with RFC 768)
With the interface via TCP connections, the CM supports the socket interface to TCP/IP
available on practically every end system.
–Multicast with UDP
The multicast mode is made possible by selecting a suitable IP address when
configuring connections. A maximum of six multicast groups are supported via UDP.
•S7 communication
–PG communication
–Operator control and monitoring functions (HMI communication)
–Data exchange over S7 connections
1.2 Further functions
Time synchronization with NTP (Network Time Protocol)
The CP can synchronize its local time of day via NTP.
For details, see section Time-of-day synchronization (Page 41).

Properties and functions
1.2 Further functions
SIMATIC CM 1542-1
12 Operating Instructions, 04/2023, C79000-G8976-C355-05
Media redundancy (MRP)
Within an Ethernet network with a ring topology, the CM supports the media redundancy
protocol MRP. You can assign the role of "Client" or "Manager (Auto)" to the CM.
Addressable with the factoryset MAC address
To assign the IP address to a new CM (direct from the factory), it can be accessed using the
preset MAC address on the interface being used. Online address assignment is made in
STEP 7.
SNMP agent
The CM supports data queries using SNMP in version V1 (Simple Network Management
Protocol).
For details, see section SNMP (Page 47).
IP configuration - IPv4
The essential features of IP configuration for the CM:
•The CM supports the use of IP addresses according to IPv4.
•You can configure how and with which method the CM is assigned the IP address, the
subnet mask and the address of a gateway.
•The IP configuration and the connection configuration (IPv4) can also be assigned to the
CM by the user program (for program blocks refer to the section Program blocks
(Page 21)).
Note: Does not apply to S7 connections.
IP routing
The CM supports static IP routing (IPv4) to other CMs/CPs.
For details, see section IP routing (Page 39).
Access to the Web server of the CPU
Via the LAN interface of the CM, you have access to the Web server of the CPU. With the aid
of the Web server of the CPU, you can read out module data from a station.
Note the special description of the Web server; refer to the section Documentation references
(Page 65)
Note
Web server access using the HTTPS protocol
The Web server of a SIMATIC S7
-1500 station is located in the CPU. For this reason, when
there is secure access (HTTPS) to the Web server of the station using the IP address of the CM
1542-1, the SSL certificate of the CPU is displayed.

Properties and functions
1.3 Security information
SIMATIC CM 1542-1
Operating Instructions, 04/2023, C79000-G8976-C355-05 13
1.3 Security information
Note
Security
•
Security recommendations
Refer to the information in the section Security recommendations (Page 35).
•
Configuration with implementation of security measures
You can find a sample network configuration with the CM and the relevant data flows can
be found in the section Intended operating environment (Page 14).
Security Advisories
If Siemens detects and resolves security incidents in the products, this is published in Security
Advisories.
You can find the documents for CM on the following Siemens AG web page:
Link: (https://new.siemens.com/global/en/products/services/cert.html?s=CM%201542-
1#SecurityPublications)
There, enter "CM 1542-1" in the "Search Security Advisories" search field.
Security Incidents and fixes
The following Security Incidents are open for the CM 1542-1 at the time of publication of this
manual:
•None
The following Security Incidents have been fixed with the listed firmware versions:
•V3.0
–SSA-462066
Vulnerability known as TCP SACK PANIC in Industrial Products
Affected versions: All versions < V3.0
Remediation: Update to V3.0 or later version
–SSA-599968
Denial-of-Service Vulnerability in Profinet Devices
Affected versions: All versions < V3.0
Remediation: Update to V3.0 or later version
–SSA-936080
Multiple Vulnerabilities in Third-Party Component libcurl
Affected versions: All versions < V3.0
Remediation: Update to V3.0 or later version

Properties and functions
1.4 Intended operating environment
SIMATIC CM 1542-1
14 Operating Instructions, 04/2023, C79000-G8976-C355-05
•V2.0
–SSA-293562
Denial of Service Vulnerabilities in PROFINET DCP Implementation of Industrial
Products
Affected versions: All versions < V2.0
Remediation: Update to V2.0 or later version
Further security-related information
You can configure the access to the CM or the station in the STEP 7 project.
For information about the ports used by the CM, refer to section Security recommendations
(Page 35).
1.4 Intended operating environment
The following figure shows a sample system configuration as intended operating
environment for the CM.
•The CM is located in the field level.
•Communication partners are also in the field or control level and in the input level.
Figure 1-1 Example of a system configuration for the intended operating environment of the CM 1542-1

Properties and functions
1.5 Configuration limits and performance data
SIMATIC CM 1542-1
Operating Instructions, 04/2023, C79000-G8976-C355-05 15
For protection of the company and plant network, the following security components are
recommended:
•External firewalls with Intrusion Detection System (IDS) protect the company network
against external attacks.
•DMZ firewalls in the backbone level protect the plant network.
•Security modules protect each individual automation cell.
Note
Security information
To protect your system, refer to the information in the section
Security recommendations
(Page 35).
1.5 Configuration limits and performance data
1.5.1 Transmission and reaction times
Measured values on the Internet
Note
Measured values of transmission and reaction times in PROFINET networks for a series of
configurations can be found on the Internet at the following address:
Link: (https://support.industry.siemens.com/cs/ww/en/view/25209605)
1.5.2 Connection resources
Characteristic
Explanation / values
Total number of freely usable
connections on Industrial Ethernet 64 configurable connections, 1 PG connection
The value applies to the total number of connections of the
following types:
•Connections for open communications services

Properties and functions
1.5 Configuration limits and performance data
SIMATIC CM 1542-1
16 Operating Instructions, 04/2023, C79000-G8976-C355-05
Note
Connection resources CPU dependent
Depending on the CPU type, different numbers of connection resources are available. The
number of connection resources is the decisive factor for the number of configurable
connections. This mea
ns that the values that can actually be achieved may be lower than
specified in this section "Properties and functions" describing the CM.
1.5.3 Characteristic data Open User Communication incl. e-mail
Open User Communication (OUC) provides access to communication over TCP, ISO-on-TCP
and UDP connections.
Characteristic
Explanation / values
Number of connections •Max. number of connections in total (configured and programmed):
(ISO-on-TCP + TCP + UDP + e-mail) ≤64
of which:
–TCP connections: 0 ... 64 1)
–ISO-on-TCP connections: 0 ... 64
–Total number of UDP connections (specified and free) that can be
configured: 0 ... 64
–Connection for e-mail: 0 to 1;
only one e-mail can be processed at any one time.
Notes:
•1) Avoid overload at receiving end
The flow control on TCP connections cannot control permanent
overload of the recipient. You should therefore make sure that the
processing capabilities of a receiving CM are not permanently
exceeded by the sender (approximately 150 200 messages per
second).
Number of multicast address ranges
Max. 6

Properties and functions
1.5 Configuration limits and performance data
SIMATIC CM 1542-1
Operating Instructions, 04/2023, C79000-G8976-C355-05 17
Characteristic
Explanation / values
Maximum data length for program blocks
Program blocks allow the transfer of user data in the following lengths:
1. ISO-on-TCP, TCP: 1 - 64 kbytes
2. UDP
–CM with article number 6GK7542-1AX00-0XE0:
1 - 1452 bytes
–CM with article number 6GK7542-1AX10-0XE0:
1 - 2048 bytes
3. E-mail (job header + user data): 1 - 256 bytes
e-mail attachment: ≤64 kbytes
LAN interface max. data field length generated
by the CM per protocol data unit (TPDU =
transport protocol data unit)
•For sending
–ISO-on-TCP, TCP: 1452 bytes / TPDU
•For receiving
–ISO-on-TCP: 512 bytes / TPDU
–TCP: 1452 bytes / TPDU
Note
Connection resources of the CPU
Depending on the CPU type, different numbers of connection resources are available. The
number of connection resources is the decisive factor for the number of configurable
connections. This means that the values that can actually be achieved may be lower
than
specified in this section describing the CM.
You will find detailed information on the topic of connection resources in the function
manual /4/ (Page 66).
Restrictions for UDP
•Restrictions UDP broadcast / multicast
To avoid overloading the CM due to high broadcast/multicast frame traffic, the receipt of
UDP broadcast/multicast on the CM is limited.
•UDP frame buffering
Length of the frame buffer: At least 7360 bytes
Following a buffer overflow, newly arriving frames that are not fetched by the user
program are discarded.

Properties and functions
1.5 Configuration limits and performance data
SIMATIC CM 1542-1
18 Operating Instructions, 04/2023, C79000-G8976-C355-05
1.5.4 Characteristics of S7 communication
S7 communication provides data transfer via the ISO-on-TCP protocol.
Characteristic
Explanation / values
Total number of freely usable S7 connections on
Industrial Ethernet
Max. 64
LAN interface - data field length generated by CM
per protocol data unit (PDU = protocol data unit) •for sending: 480 bytes / PDU
•for receiving: 480 bytes / PDU
Note
Maximum values for an S7
-1500 station
Depending on the CPU you are using, there are li
mit values for the S7-1500 station. Note the
information in the relevant documentation.
1.5.5 PROFINET IO characteristic data
Configuration limits of the CM as an IO controller
The CM supports the following maximum configuration as a PROFINET IO controller:
Characteristic
Explanation / values
Number of operable PROFINET IO devices
128, of which:
•Max. 64 IRT devices
Size of the input area over all PROFINET IO devices *)
Max. 8192 bytes
Size of the output area over all PROFINET IO devices
Max. 8192 bytes
Size of the IO data area per submodule of a module in an IO
device •Inputs: 256 bytes
•Outputs: 256 bytes
Size of the consistency area for a submodule
256 bytes
*) The diagnostics addresses of the PROFINET IO devices cannot be used as an input on the IO controller. The data area of
the inputs is reduced by the diagnostics addresses used.

Properties and functions
1.6 Requirements for use
SIMATIC CM 1542-1
Operating Instructions, 04/2023, C79000-G8976-C355-05 19
1.5.6 Rack components
When using the CM type described here, the following limits apply:
•The number of CMs that can be operated in a rack depends on the CPU type being used.
By operating several CMs, you can increase the configuration limits listed in the section
Properties and functions (Page 11) for the station as the whole. The CPU does, however,
have set limits for the entire configuration.
Note the information in the documentation of the CPU, refer to the section
Documentation references (Page 65)
Note
Power supply via the CPU adequate or additional power supply modules required
You can operate a certain number of modules in the S7
-1500 station without an
additional power supply. Make sure that you keep to the specified power feed to the
backplane bus for the particular CPU type. Depending on the configuration of the S7
-
1500
station you may need to provide additional power supply modules.
1.6 Requirements for use
1.6.1 Usable CPUs
The following CPUs can be used as local CPU of the communications module:
•Compatible CPUs
All CPUs that can be configured in STEP 7 as of firmware version V2.1 from the following
series:
–Standard CPUs (CPU 15xx)
–Compact CPUs (CPU 15xxC)
–Technology CPUs (CPU 15xxT / TF)
–Fail-safe CPUs (CPU 15xxF)
The following CPUs cannot be used:
•Non-compatible CPUs
–H-CPU (CPU 1517H / HF)
–R-CPUs (CPU 151xR)

Properties and functions
1.6 Requirements for use
SIMATIC CM 1542-1
20 Operating Instructions, 04/2023, C79000-G8976-C355-05
Note
Keep the firmware version of the CPUs and communications modules up to date
To avoid possible problems when using newer CPUs together with older commun
ications
modules, you should keep the firmware of both your communications modules and your
CPUs up to date.
Check regularly for security updates for the firmware and use them.
Information regarding product news and new firmware versions of the communicati
ons
module is available at the following address:
Link: (https://support.industry.siemens.com/cs/ww/en/ps/15341/dl)
1.6.2 Project engineering
Software for configuration and online functions
To configure the CM, the following configuration tool is required:
STEP 7 version
CM (6GK7542-1AX00-0XE0)
CM (6GK7542-1AX10-0XE0)
STEP 7 Professional V14 The functionality of the CM with
firmware version V2.0 can be
configured.
The CM is configurable, but with
the functionality of the CM
(6GK7542-1AX00-0XE0) with
firmware version V2.0.
STEP 7 Professional V17
The full functionality of the CM
with firmware version V3.0 can be
configured.
The CM is configurable, but with
the functionality of the CM
(6GK7542-1AX00-0XE0) with
firmware version V3.0.
STEP 7 Professional V18
The full functionality of the CM
with firmware version V3.0 can be
configured.
The full functionality of the CM
with firmware version V4.0 can be
configured.
Downloading the configuration data
When there is a download to the CPU, the CM is supplied with the relevant configuration
data. The configuration data can be downloaded to the CPU via a memory card or any
Ethernet/PROFINET interface of the S7-1500 station.