Mitsubishi Electric MELSEC iQ-R-R04CPU - Program Execution Type; Initial Execution Type Program

1 RUNNING A PROGRAM
1.5 Program Execution Type
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1.5 Program Execution Type
Set the execution condition of the program. ( Page 64 Execution type change)
Initial execution type program
Initial execution type program is executed only once when the CPU module has been powered off and on, or switched from
the STOP state to the RUN state. Use this execution type for a program, for example, initial processing for the intelligent
function module, which does not need execution after executed once in the initial scan.
Note that the execution time of the initial execution type program is the same as the initial scan time. ( Page 40 Initial
scan time) When multiple initial execution type programs are executed, the execution time of the initial execution type
program will be the total time until all the initial execution type programs finish execution.
*1 The sum of the initial execution type program execution time and END processing time is the initial scan time.
Precautions
The following lists the precautions for the initial execution type programs.
■Restrictions on program creation
In the initial execution type program, do not use an instruction which requires several scans to complete (i.e., an instruction
with a completion device).
Ex.
e.g. SEND and RECV instructions
(1) Divides programs into the initial execution type programs and scan
execution type programs.
(1)
When controlled by one program
Program B
Program A
When controlled by separate programs
(an initial execution type program is used)
Processing performed
only once
Processing performed
in each scan
Initial execution type
program
Scan execution type
program
END
0
0
END
END0
0
0
END END
0
*1
Power-on → RUN,
STOP → RUN
END processing
Initial execution type program A
Initial execution type program B
Initial execution type program C
Scan execution type program
First scan Second scan Third scan