259
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
10 Arithmetic and Logical Operation (
+
,
−
,
×
,
÷
) – FNC 20 to FNC 29
10.6 FNC 25 – DEC / Decrement
1
In
troduct
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2
Ov
e
rv
ie
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3
In
st
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ion
Li
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D
evi
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s
in
De
ta
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Speci
fied t
h
e
D
evi
ce &
C
onst
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nt
6
Bef
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re
Pr
ogr
a
m
m
ing
7
Bas
ic
In
st
ru
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8
FNC0
0
-FNC0
9
P
ro
g
ra
m F
lo
w
9
FNC1
0
-FNC1
9
M
ov
e
&
C
om
par
e
10
FNC
20-
FNC
2
9
Ar
ith.
&
Logi
c
O
per
at
io
n
10.6
FNC 25 – DEC / Decrement
Outline
This instruction decrements the data of a specified device by "1".
1. Instruction format
2. Set data
3. Applicable devices
Explanation of function and operation
1. 16-bit operation (DEC and DECP)
The contents of
are decremented by "1", and the decremented result is transferred to
.
2. 32-bit operation (DDEC and DDECP)
The contents of [
+1,
] are decremented by "1", and the decremented result is transferred to
[
+1,
].
Cautions
1. Flag operations
1) 16-bit operation
When "
−
32768" is decremented by "1", the result is "+32767". Flags (zero, carry and borrow) are not
activated at this time.
2) 32-bit operation
When "
−
2,147,483,648" is decremented by "1", the result is "+2,147,483,647". Flags (zero, carry and
borrow) are not activated at this time.
Operand type
Description
Data type
Word device number storing data to be decremented by "1"
16- or 32-bit binary
Oper-
and
Type
Bit Devices
Word Devices
Others
System User
Digit Specification
System User
Special
Unit
Index
Con-
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
3
3
3
3 3 3 3
3
3 3
3
DDEC
DDECP
Mnemonic
Operation Condition
P
FNC 25
DEC
D
16-bit Instruction
3 steps
DEC
DECP
Mnemonic
Operation Condition
Continuous
Operation
Pulse (Single)
Operation
32-bit Instruction
5 steps
Continuous
Operation
Pulse (Single)
Operation
D
D
D
D
Command
input
FNC 25
DECP
D
−
1
→
D
D
D
D
D
D
Command
input
FNC 25
DDECP
D
D
[ +1, ]
−
1
→
[ + 1, ]
D
D
D