407
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
15 External FX I/O Device – FNC 70 to FNC 79
15.3 FNC 72 – DSW / Digital Switch (Thumbwheel Input)
11
FN
C30-
FN
C39
R
o
ta
tion and
Sh
ift
12
FNC
4
0
-FNC49
D
a
ta
Op
e
ra
tio
n
13
FNC5
0
-FNC5
9
H
igh Speed
Pr
ocessi
ng
14
FM
C6
0
-F
NC6
9
H
and
y
In
st
ru
cti
o
n
15
FNC7
0
-FNC7
9
Ex
te
rn
a
l F
X
I
/O
D
evi
ce
16
FNC8
0
-FNC8
9
Ext
e
rnal
FX
D
evi
ce
17
F
N
C1
00
-F
NC
10
9
Da
ta
Tr
ansf
e
r 2
18
FN
C
110-FN
C
13
9
Fl
oat
ing P
o
in
t
19
FN
C
140-FN
C
149
Da
ta
O
per
at
io
n
2
20
FN
C
15
0-F
N
C
159
P
o
si
tioni
ng
C
ont
ro
l
2) Specification of the number of sets ("n")
- When using one set of 4 digits [n = k1]
A 4-digit BCD digital switch connected to
to
+3 is read in turn by the strobe signal
to
+3, and stored in the binary format to
.
- When using two sets of 4 digits [n = k2]
A 4-digit BCD digital switch connected to
to
+3 is read in turn by the strobe signal
to
+3, and stored in the binary format to
.
A 4-digit BCD digital switch connected to
+4 to
+7 is read in turn by the strobe signal
to
+3, and stored in the binary format to
+1.
Related devices
→
For the instruction execution complete flag use method, refer to Subsection 6.5.2.
Cautions
1. When the command contact turns OFF
Though the contents of
do not change, all of
to
+3 turn OFF.
2. Number of occupied devices
1) When two sets of 4 digits (n = K2) are used, two devices are occupied starting from
.
2) When one set of 4 digits is used, four devices are occupied starting from
. When two sets of 4 digits
is used, eight devices are occupied starting from
.
3. When connecting a digital switch of up to 3 digits
It is not necessary to wire the strobe signal (output for digit specification)
to unused digits. Because
unused digits are occupied also by this instruction, however, they cannot be used for any other purpose.
Make sure to leave unused outputs vacant.
4. Transistor output type is recommended
For continuously receiving digital switch values, make sure to use a transistor output type PLC.
→
For a relay type PLC, refer to "How to use this instruction in a relay output type PLC" later.
5. Digital switches
Use BCD output type digital switches.
Program example
In the program example shown below, digital switches are connected to inputs starting from X010 and outputs
from Y010.
1. Program
Device
Name
Description
M8029
Instruction execution
complete flag
OFF: Data is being output to
to
+3 or the instruction is not executed yet.
ON:
A cycle operation of outputting data to
to
+3 (scan of the 1st to 4th
digits) is completed.
S
S
D
1
D
1
D
2
S
S
D
1
D
1
D
2
S
S
D
1
D
1
D
2
D
1
D
1
D
1
D
1
D
2
D
1
D
1
D
2
S
S
D
1
X000
FNC 72
DSW
X010
Y010
D 0
K 1
n
D
1
S
D
2
