Mitsubishi Electric MELSEC iQ-R-R6SFM - Scan Execution Type Program; Fixed Scan Execution Type Program

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1 RUNNING A PROGRAM
1.5 Program Execution Type
Scan execution type program
Scan execution type program is executed only once per every scan starting from the scan following the scan in which the
initial execution type program was executed.
When multiple scan execution type programs are executed, the execution time of the scan execution type program will be the
total time until all the scan execution type programs finish execution. Note that if interrupt program, fixed scan execution type
program, and/or event execution type program are executed before the scan execution type program finishes execution, the
execution time for these programs is also included.
Fixed scan execution type program
An interrupt program which is executed at a specified time interval. Differently from the normal interrupt program, this type of
program does not require the interrupt pointer (I) and the IRET instruction and is executed for each program file unit.
To execute a fixed scan execution type program, the EI instruction must be used to enable interrupts.
0
END0
END0
END0
END0
END0
END0
END0
Scan time
Scan execution type program B
Scan execution type program C
Scan execution type program A
Initial execution type program
END processing
Power-on→RUN,
STOP→RUN
4th scan3rd scan2nd scan1st scan
Condition
established
Condition
established
Fixed scan execution type program
Scan execution type program
END processing
Fixed scan interval