Mitsubishi QCPU (Q Mode) User Manual

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MELSEC-Q
4 SEQUENCE PROGRAM CONFIGURATION AND EXECUTION
CONDITIONS
4.1.1 Main routine program
(1) Definition of main routine program
(a) A main routine program begins from step 0 and ends at the END/FEND
instruction.
1
(b) In the main routine program, the instructions are executed from step 0 to the
END/FEND.
1) If only one program is executed, the program is operated from step 0
again after the END/FEND instruction is executed and the END
instruction is processed.
END/FEND
Main routine
program
Step 0
END/FEND
END processing
Program execution
Returns to step 0 when only one
program is being executed.
2) If multiple programs are being executed, each of them will be operated
according to the designated execution conditions after the END/FEND
instruction is processed.
(2) Execution conditions for main routine programs 2
If multiple programs are being executed, the following five types of execution
conditions can be designated by the program in the PLC parameters according to
the application.
• Initial execution program : See Section 4.2.1.
• Scan execution type program : See Section 4.2.2.
• Low speed execution type program : See Section 4.2.3.
• Stand-by type program : See Section 4.2.4.
• Fixed scan execution type program : See Section 4.2.5.
REMARK
1: For details on the END/FEND instruction, refer to the "QCPU (Q
mode)/QnACPU Programming Manual (Common Instructions)".
2: If only one program is executed, it is processed under the "scan execution type
program" condition without designation by the program in the PLC parameters.

Mitsubishi QCPU (Q Mode) Specifications

General

Brand	Mitsubishi
Model	QCPU (Q Mode)
Category	Controller
Language	English