Mitsubishi Electronics FX3G User Manual
217
FX
3S
/FX
3G
/FX
3GC
/FX
3U
/FX
3UC
Series
Programming Manual - Basic & Applied Instruction Edition
7 Basic Instruction
7.14 NOP
1
Introdu
ction
2
Ov
ervi
ew
ew
3
Instruction
Li
st
4
D
evices
in Det
ai
l
5
Specifi
ed the
De
vice
&
C
onst
ant
ant
6
Bef
ore
ore
Pr
og
ra
mmi
ng
ng
7
Bas
ic
ic
Instruction
8
FN
C00-FN
C00-FN
C0
9
Program Fl
ow
9
FNC
10-FN
C19
Mov
e & Com
e & Com
pare
10
FNC
20-FNC
29
Arith. & Lo
gi
c
Operati
on
7.14
NOP
Outline
NOP instruction specifies no operation.
When a program is erased completely, all steps are replaced with NOP instructions.
When NOP instruction is located between general instructions, PLCs ignore NOP instruction.
If NOP instructions are put in the middle of a program, fluctuation of step numbers is minimized when the program is
changed or added. But excessive program steps are required.
Note that circuits are considerably changed if already written instructions are replaced with NOP instructions.
When a program is erased completely, all steps are replaced with NOP instructions.
When NOP instruction is located between general instructions, PLCs ignore NOP instruction.
If NOP instructions are put in the middle of a program, fluctuation of step numbers is minimized when the program is
changed or added. But excessive program steps are required.
Note that circuits are considerably changed if already written instructions are replaced with NOP instructions.
1. Instruction format
2. Applicable devices
Explanation of function and operation
1. NOP instruction (no operation or null step)
NOP instruction specifies no operation.
If NOP operation is written in the middle of a program, PLCs ignore it in executing the program.
When an existing program is replaced with NOP instructions, it means that former instructions are deleted.
If NOP operation is written in the middle of a program, PLCs ignore it in executing the program.
When an existing program is replaced with NOP instructions, it means that former instructions are deleted.
Instruc-
tion
Bit Devices
Word Devices
Others
System User
Digit Specification
System User
Special
Unit
Index
Con-
stant
stant
Real
Number
Charac-
ter String
Pointer
X Y M T C S D .b KnX KnY KnM KnS T C D R U \G
V Z Modify K H
E
" "
P
NOP
There are no applicable devices.
NOP
No Operation
Basic Instruction
NOP
−
Continuous
Operation
Pulse (Single)
Pulse (Single)
Operation
Mnemonic
Operation Condition
1 step
AND
→ NOP
ANI
→ NOP
Contact becomes
short-circuit.
OR
→ NOP
Circuit is
disconnected.
ORI
→ NOP
OUT
→ NOP (error)