Siemens SIMATIC S7-1200

Communication
11.4 AS-i
S7-1200 Programmable controller
System Manual, V4.2, 09/2016, A5E02486680-AK
975
11.4
AS-i
The S7-1200 AS-i master CM 1243-2 allows the attachment of an AS-i network to an S7-
1200 CPU.
The actuator/sensor interface, or AS-i, is a single master network connection system for the
lowest level in automation systems. The CM 1243-2 serves as the AS-i master for the
network. Using a single AS-i cable, sensors and actuators (AS-i slave devices) can be
connected to the CPU through the CM 1243-2. The CM 1243-2 handles all AS-i network
coordination and relays data and status information from the actuators and sensors to the
CPU through the I/O addresses assigned to the CM 1243-2. You can access binary or
analog values depending on the slave type. The AS-i slaves are the input and output
channels of the AS-i system and are only active when called by the CM 1243-2.
In the figure below, the S7-1200 is an AS-i master controlling AS-i I/O module digital/analog
slave devices.
To use AS-i with S7-1200 V4.0 CPUs, you must upgrade the AS-i Master CM firmware to
V1.1.
You can make this upgrade using the webserver or a SIMATIC memory card.
Note
For V4.0 S7
-1200 CPUs, if using the web server or a SIMATIC memory card to upgrade
from V1.0 to V1.1 AS
-i firmware, you must update the AS-i firmware in the AS-i Master CM
1243
-2 according to the following procedure:
1.
Download the firmware upgrade to the AS-i Master CM 1243-2.
2.
When the download is complete, power cycle the S7-1200 CPU to complete the firmware
upgrade process in the AS-i Master CM 1243-2.
3.
Repeat steps 1 and 2 for each additional AS-i Master CM 1243-2. The S7-1200 PLC
allows a maximum of three AS-i Master CM 1243-2.
Note
It is recommended that you alw
ays update the AS-i CM firmware to the latest version
available (
http://support.automation.siemens.com/WW/view/en/43416171)at the Siemens
Service and Support web site.