155
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
7 Basic Instruction
7.1 LD, LDI
1
In
troduct
io
n
2
Ov
e
rv
ie
w
3
In
st
ru
ct
ion
Li
st
4
D
evi
ce
s
in
De
ta
il
5
Speci
fied t
h
e
D
evi
ce &
C
onst
a
nt
6
Bef
o
re
Pr
ogr
a
m
m
ing
7
Bas
ic
In
st
ru
cti
o
n
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
7.1
LD, LDI
Outline
LD and LDI instructions are contacts connected to bus lines.
When combined with ANB instruction described later, LD and LDI instructions can be used for the start of
branches.
1. Instruction format
→
For the number of instruction steps, refer to Section 7.15.
2. Applicable devices
S
1: Special auxiliary relays (M) and 32-bit counters (C) cannot be indexed with index registers (V and Z).
S
2: State relays (S) and "D
.b" cannot be indexed with index registers (V and Z).
Explanation of function and operation
1. LD instruction (initial logical operation, NO contact type)
Instruc-
tion
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
LD
3 3
S
1
3
S
1
S
2
S
2
3
LDI
3 3
S
1
3
S
1
S
2
S
2
3
LD
Load
Basic Instruction
LD
−
Continuous
Operation
Pulse (Single)
Operation
Mnemonic
Operation Condition
LDI
Load
Inverse
Basic Instruction
LDI
−
Continuous
Operation
Pulse (Single)
Operation
Mnemonic
Operation Condition
X000
Y000
LD instruction
Circuit program
List program
LD
OUT
0000
0001
X000
Y000
Connection to bus line
ON
ON
X000
ON
ON
Y000
Timing chart
Bus line