Isochronous Mode - Siemens SIMATIC ET 200S Operating Instructions Manual

5.2

Isochronous mode

Note
For basic information on isochronous mode, refer to the Isochronous mode
(http://support.automation.siemens.com/WW/view/en/15218045) function manual.
Hardware requirements
You will require the following for the 2PULSE in isochronous mode:
● A CPU that supports isochronous mode
● PROFIBUS master or PROFINET controller that supports the constant bus cycle time
● IM 151 that supports isochronous mode
Response of the 2PULSE
Depending on the system parameter assignment, the 2PULSE works in either non-
isochronous or isochronous mode.
In isochronous mode
● The output sequences are started at the moment T
● Data communication between the bus master and 2PULSE is isochronous to the cycle.
● All 8 bytes of the feedback interface are consistent.
In case of a parameter assignment error, the 2PULSE does not go into isochronous mode.
If isochronous mode fails due to faults or failure/delay of global control (GC), the 2PULSE
returns to isochronous mode during the next cycle without an error response.
If isochronous mode fails, the feedback interface is not updated.
Technological Functions
Operating Instructions, 06/2010, A5E00124867-07
5.2 Isochronous mode
when the software is enabled.
o
2PULSE
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