657
FX
3G
/FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
28 Data Comparison – FNC220 to FNC249
28.1 FNC224~230 – LD =, >, <, <>, <=, >= / Data Comparison
21
FNC160
-F
NC1
69
R
eal
T
ime C
lock
C
ontrol
22
FNC17
0-F
NC
179
E
xternal D
evice
23
FNC
180
Alternate
Instructions
24
FN
C181-
FNC18
9
O
thers
25
FNC190
-F
NC1
99
Bl
oc
k D
ata
Op
er
atio
n
26
FNC20
0-F
NC209
C
har
ac
te
r S
trin
g
Con
tro
l
27
FNC2
10-
FNC21
9
Dat
a
Operati
on 3
28
FNC220
-F
NC2
49
Da
ta
C
omp
ari
son
29
FNC25
0-F
N
C
269
D
ata T
abl
e
Operation
30
FNC2
70-
FNC275
Ex
-Dev
ice
Inverter C
om
m
s
Explanation of function and operation
FNC224 to FNC230 are data comparison instructions connected to bus lines.
The contents of
are compared with the contents of
in binary format, and a contact becomes conductive
(ON) or non-conductive (OFF) depending on the comparison result.
Cautions
1. Negative value
When the most significant bit is "1" in the data stored in
or
, it is regarded as a negative value in
comparison.
• In the 16-bit operation: bit 15
• In the 32-bit operation: bit 31
2. When using 32-bit counters (including 32-bit high-speed counters)
Make sure to execute the 32-bit operation (such as "LDD=", "LDD>" and "LDD<") when comparing 32-bit counters
(C200 to C255).
If a 32-bit counter is specified in the 16-bit operation (such as "LD=", "LD>" and "LD<"), a program error or operation
error will occur.
3. Programming of data comparison instructions
When programming in GX Developer, symbols "
≤
" and "
≥
" cannot be input.
Separate "
≤
" into "<" and "=", and separate "
≥
" into ">" and "=".
The input procedure is described below:
Operating procedure
a) Display the circuit program edit window, and put the cursor in a position where a data comparison instruction
is to be used.
b) Input "Instruction"
→
"space"
→
"value or device"
→
"space"
→
"value or device".
For an input example, refer to "Instruction input window in GX Developer" shown below.
c) Click the [OK] button.
d) Input other contacts and coil drive units consecutively.
Instruction input window in GX Developer
Program example
FNC No.
16-bit instruction
32-bit instruction
ON condition
OFF condition
224
LD=
LDD=
=
≠
225
LD>
LDD>
>
<=
226
LD<
LDD<
<
>=
228
LD<>
LDD<>
≠
=
229
LD<=
LDD<=
<=
>
230
LD>=
LDD>=
>=
<
S
1
S
2
S
1
S
2
S
1
S
2
S
1
S
2
S
1
S
2
S
1
S
2
S
1
S
2
S
1
S
2
S
1
S
2
S
1
S
2
S
1
S
2
S
1
S
2
S
1
S
2
S
1
S
2
<Input example for 16-bit operation>
<Input example for 32-bit operation>
C10
FNC224
LD=
K200
S
1
S
2
Y10
K-30
FNC225
LD>
D200
X001
SET
Y11
C200
FNC225
LDD>
K678493
M50
M3
When the current value of the counter C10 is "200", Y010
is driven.
When the contents of D200 are "-29" or higher and X001 is
ON, Y011 is set.
When the contents of the counter C200 are less than
"K678,493" or when M3 turns ON, M50 is driven.