Siemens SIMATIC ET 200AL, System Manual

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Programming
4.3 Time-based IO
High-precision input/output with Time-based IO
Function Manual, 11/2019, A5E33454822-AC
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4.3 Time-based IO
4.3.1 TIO_SYNC: Synchronizing TIO modules
Description
TIO_SYNC is the basis for all other TIO instructions. TIO_SYNC synchronizes TIO modules
to a shared time basis TIO_Time.
You can synchronize up to 8 TIO modules with TIO_SYNC. All TIO modules must be
assigned to the same process image partition (PIP). If you select "0" for the input parameter
PIP_Mode, you assign the number of the process image partition at the PIP_PART input
parameter.
Additional information on configuration of Time-based IO is available in the Configuration
and parameter assignment section.
Startup characteristics
At the startup of the CPU, the TIO_SYNC instruction receives and checks the input
parameters once and initializes the TIO_Time.
You have several options for handling the optional parameters SendClock, AppCycleFactor
and ToTimes:
● SendClock, AppCycleFactor and ToTimes can be read in automatically each time the
system is started. This results in a time delay during startup, but the values are always
consistent.
● Automatically read in SendClock, AppCycleFactor and ToTimes at each startup and apply
the read-in values as set values during commissioning. This results in fast subsequent
startups, but is inconsistent after changes in the hardware configuration (repeat
commissioning necessary).
● Manually define SendClock, AppCycleFactor and ToTimes before the first call of the
instruction, for example, in OB100:
This results in a fast startup, but you need to manually update the values after changes to
the hardware configuration.
You will find information about the parameters in the table below.
If startup takes place without errors, the instruction changes to normal operation. In the event
of an error, the instruction does not change to normal operation and generates an error
message.