Download QCPU(Q Mode)/QnACPU Programming Manual(Common

5 SEQUENCE INSTRUCTIONS
MELSEC-Q/QnA
QCPU
PLC CPU
Basic
High Performance
Process CPU
QnA
Q4AR
5.6 Termination Instructions
5.6.1 End main routine program (FEND)
Set
Data
Internal Devices
(System, User)
Bit
Usable Devices
Special
MELSECNET/10(H)
Function
Direct J \
Module
Bit
Word
U \G
File
Register
Word
Index
Register
Zn
Constant
Other
[Instruction Symbol] [Execution Condition]
FEND
FEND
[Functions]
(1) The FEND instruction is used in cases where the CJ instruction or other instructions are used
to cause a branch in the sequence program operations, and in cases where the main routine
program is to be split from a subroutine program or an interrupt program.
(2) Execution of the FEND instruction will cause the CPU module to terminate the program it was
executing.
(3) Even sequence programs following the FEND instruction can be displayed in ladder display at
a peripheral devices. (Peripheral devices continue to display ladders until encountering an
END instruction.)
0
program
CJ
Operations when
the CJ instruction
is not executed
P
Main routine
program
FEND
P
CALL P
Main routine
Main routine
Jump caused by
the CJ instruction
program
Operation
performed when P
the CJ instruction
was executed
FEND
Subroutine
program
I
Main routine
Interrupt program
program
FEND
END
END
(a) When using the CJ instruction
(b) When there is a subroutine
or interrupt program
[Operation Errors]
(1) In the following cases an operation error occurs, the error flag (SM0) turns ON, and an error
code is stored at SD0.
• A FEND instruction is executed after the execution of a CALL, FCALL, ECALL, or EFCALL
instruction, and before the execution of the RET instruction.
(Error code: 4211)
• A FEND instruction is executed after the execution of a FOR instruction, and before the
execution of a NEXT instruction.
(Error code: 4200)
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