Mitsubishi Electric MELSEC iQ-F FX5 User Manual page 87

Conditions of setting time
Set a value that meets the following relational equation for the setting time of the constant scan.
"WDT setting time" > "Constant scan setting time" > "Maximum scan time of the program"
When the maximum scan time of the program is longer than the setting time of the constant scan, it results in error. The
constant scan time is ignored and it is executed with the scan time of the program.
Ex.
When the constant scan time is set to 4 ms
Constant scan (4 ms)
0 1 2 3 4 1 2
END 0 END 0
1 ms 2 ms 1 ms
4 ms 5.3 ms
Scan where the constant scan setting is not applied
Wait time from the execution of END process until the beginning of the next scan
When there is a processing mentioned below requested during wait time, the processing of the program is interrupted and the
corresponding process is carried out.
• Interrupt program
• Event execution type program which triggers the generation of interruption
• Device/label access service processing
3 4 5 1 2 3 4
END 0 END 0
1 ms 2 ms 1 ms 1 ms
4 ms
1 2 3 4 ms
2 ms 1 ms
4 ms
10 CONSTANT SCAN
10.1 Constant scan settings
10
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