Isochronous Mode - Siemens SIMATIC S7-1500/ET 200МР Manual

Configuring/address space
4.2 Position input for "Motion Control" technology object
4.2.5

Isochronous mode

The technology module supports the "Isochronous mode" system function. Counter values
can be acquired in a fixed system cycle with this system function.
In isochronous mode, the cycle of the user program, the transmission of the input signals and
processing in the technology module are synchronized. A change in the state of a digital
input immediately affects the planned reaction of the technology module.
For clock synchronization in this operating mode, use an OB of type "MC-Servo". Isochronous
mode is needed when using the output cam and cam track technology objects. When the
measuring input technology is used in combination with hardware digital input DI1,
isochronous mode is not needed.
Data processing
The data that was transmitted to the technology module in the current bus cycle via the
control interface takes effect when it is processed in the internal technology module cycle. At
the time the input data is read in (T
made available in the feedback interface for retrieval in the current bus cycle.
Isochronous mode parameters
In isochronous mode, the "Filter frequency" parameter can affect the isochronous mode
parameters of the sync domain.
Because the isochronous parameters are not checked in RUN, changing the parameter in RUN
can result in the technology module no longer processing the control and feedback interface
correctly. You prevent this by selecting the option with the greatest time demand as early as
during the offline parameter assignment.
Additional information
You can find a detailed description of isochronous mode in the following:
• In the Isochronous mode function manual as a download from the Internet
(https://support.industry.siemens.com/cs/ww/en/view/109755401).
• Function manual PROFINET with STEP 7 available for download on the Internet
(https://support.industry.siemens.com/cs/ww/en/view/49948856)
36
), the counter value and the status bits are acquired and
i
Technology module TM Count 2x24V (6ES7550-1AA01-0AB0)
Equipment Manual, 12/2020, A5E31870371-AC