3
SEQUENCE PROGRAM EXECUTION
3.3 Operation Processing
3.3.2 I/O refresh
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3.3.2 I/O refresh
I/O data between CC-Link Safety master module and network module are refreshed by I/O
refresh.
The I/O refresh is executed before the sequence program operation starts.
3.3.3 END processing
This is a post-processing to return the sequence program execution to step 0 after
completing the whole sequence program operation processing once.
The END processing includes the following.
• Self-diagnostic processing (
• Communication with external device such as GX Developer
• Processing of instructions dedicated to intelligent function modules
• Network refresh processing
• CC-Link Safety refresh processing
• Constant wait processing
• Watchdog timer reset processing (
• Setting values in the special relays/special registers in the set timing END processing.
(
POINT
When the constant scan function (
Section 6.9) is set, the result of END
processing is retained during the waiting time after the END processing or before
the next scan.
Summary of Contents for MELSEC QS Series
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