Basics
3.20 Operational sequence
S7-1500 Motion Control V13 Update 3
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Function Manual, 07/2014, A5E03879256-AC
3.20.2
Process image partition "OB Servo PIP"
The process image partition "OB Servo PIP" is made available in isochronous mode for
Motion Control. All drives and encoders used by Motion Control are assigned to this process
image partition.
Additionally, you should assign all I/O modules used by Motion Control to this process image
partition (e.g. hardware limit switches). The assignment results in chronologically
synchronous processing with the technology object.
The input process image partition is also updated in STOP mode.
Process image partition in the user program
As of CPU version V1.5, you can access the process image partition "TPA OB Servo" in your
user program. This makes it possible to evaluate the process image partition using the trace
and logic analyzer function.
3.20.3
Operational Sequence and Timeouts
When processing the motion control functionality, the organization blocks MC-Servo [OB91]
and MC-Interpolator [OB92] are called and processed in each application cycle. The
remaining cycle time is available for the processing of your user program.
For error-free program execution, keep to the following rules:
●
In each application cycle, MC-Servo [OB91] must be started and executed completely.
●
In every application cycle, the relevant MC-Interpolator [OB92] must at least be started.
The following figure shows an example of the error-free operational sequence for the
processing of organization block OB1: