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Entry type: Product note Entry ID: 72865595, Entry date: 08/25/2015

Delivery release: CM AS-i Master ST for ET 200SP

  • Entry
  • Associated product(s)
Innovation for AS-i in stock: The Modular AS-i Master for ET 200SP

Date for the Release for Delivery : 2013-04-30



Product description:

AS-Interface connects sensors and actuators to plant system controls via a simple two-wire line - the yellow AS-i cable. The required AS-i bus nodes are distributed almost anywhere in the system, just easy, flexible and efficient. You can now use the AS-i Master in the same easy, flexible and efficient way: 
With the CM AS-i Master ST, Siemens offers a communication module for the scalable distributed I/O system ET 200SP that is to be used in an extremely versatile manner.

Now, via a single module, an existing ET 200SP station can be extended with up to 496 inputs and 496 outputs on the AS-Interface bus.  



Using a PROFINET interface module (IM) of the ET 200SP, it is easy to set up a PROFINET/AS-i Link. As several CM AS-i Masters can be plugged into the ET 200SP, expanding such a link to a double or multiple master is no problem - up to 8 AS-i Masters can be operated behind one IM 155-6PN ST. Such an AS-i link can be additionally assigned local inputs and outputs directly in the ET 200SP rack thanks to the use of further I/O modules from the wide delivery spectrum of the ET 200SP.  With the PROFIBUS interface module, PROFIBUS/AS-i Link can also be set up in a completely flexible range of configurations.

These modular AS-i Links are configured and programmed in the TIA portal (V12 or higher), with every single AS-i Slave being displayed and diagnosed on the screen, or in STEP 7 (classic) V5.5 SP3 or higher.

In combination with an ET 200SP CPU 1510SP / 1512SP / 1515SP PC (as of firmware V1.8 or higher), the preprocessing of AS-i signals is possible directly in the ET 200SP station as well as the configuration of a stand-alone AS-i station without a higher-level CPU.

Safety-related applications can be realized by a combination with the module F-CM AS-i Safety ST, see 90880044

An overview about the possible combinations of the modules CM AS-i Master ST and F-CM AS-i Safety ST together with the ET 200SP Interface Modules and ET 200SP CPU Controllers, see   103624653



Performance characteristics CM AS-i Master ST:

  • Up to 62 AS-Interface slaves can be connected

  • Supports all AS-Interface master functions according to the AS-Interface specification V3.0

  • User-friendly configuration in TIA Portal (with graphical display of the AS-i line), in STEP 7 classic 
    or via GSD in other systems

  • Supplied by the AS-Interface cable

  • Suitable for AS-i Power24V and for AS-Interface with 30 V voltage

  • Integrated ground-fault monitoring for the AS-Interface cable

  • Thanks to connection to AS-Interface, the available number of digital inputs and outputs for the controller is drastically increased in combination with the ET 200SP (max. 496 DI/496 DQ on the AS-Interface for each CM)

  • Integrated analog value processing (all analog profiles)

Additional functions as of firmware V1.1 (or higher):

● Option handling at the level of the AS-i slaves
● Bus configuration can be expanded and modified during operation (proxy slaves)
● Comprehensive configuring of the AS-i slaves in STEP 7 possible
● Length of process image can be expanded up to 288 bytes (with PROFINET IM155-6PN HF)or up to 256 bytes (with PROFINET IM155-6PN ST).Length of process image up to 32 bytes with PROFIBUS IM155-6DP HF.
● Length of process image can be reduced to less than 32 bytes
● Analog data transfer in the cyclic process image
● Free positioning of the slave input/output data in the process image
● Basic diagnostics in the cyclic process image (status bits)
● Detailed diagnostics via data set
● Simplified reading of the error counters
● ID1 code assignment with automatical adaption from the configuration possible
● ID1 code assignment to any address manually possible
● Detection of multiple addresses optimized


You will find informations on further product characteristics and notes on how to download latest firmware versions and Hardware Support Package (HSP), see 108742051

In addition, relevant GSD files for the ET 200SP are available for use in Step7  or in other systems.

Download of PROFINET GSD ET 200SP: 57138621

Download of PROFIBUS GSD ET 200SP: 73016883


Further information:

Manual “CM AS-i Master ST for SIMATIC ET 200SP“: 71756485

Manual "F-CM AS-i Safety ST for SIMATIC ET 200SP": 90265988 

System Manual "SIMATIC ET 200SP ET 200SP distributed I/O system": 58649293

Manual "SIMATIC ET 200SP BaseUnits": 59753521

AS-interface on the Internet:

ET 200SP on the Internet (including AS-interface connection):

Click on "Discover more" -> "stronger" -> "AS-Interface"


Ordering data:

Product name


Order No.

CM AS-i Master ST

AS-Interface communication module for ET 200SP




BaseUnit type C0
for connection of the
CM AS-i Master ST
in the ET 200SP


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