3. Instruction Set
3-471
API Mnemonic Operands Function
224~
230
D
LD※
Contact Type Comparison
Controllers
ES2/EX2 SS2 SA2
SE
SX2
Bit Devices Word devices Program Steps
Type
OP
X Y M S K H KnX KnY KnM KnS T C D E F
S
1
* ** * * * * * ***
S
2
* ** * * * * * ***
LD※: 5 steps
DLD※: 9 steps
PULSE 16-bit 32-bit
ES2/EX2 SS2
SA2
SE
SX2 ES2/EX2 SS2
SA2
SE
SX2 ES2/EX2 SS2
SA2
SE
SX2
Operands:
S
1
: Source device 1 S
2
: Source device 2
Explanations:
1. This instruction compares the content in S
1
and S
2
. Take API224 (LD=) for example, if the
result is “=”, the continuity of the instruction is enabled. If the result is “≠”, the continuity of the
instruction is disabled.
2. LD※ (※: =, >, <, <>, ≤, ≥) instruction is used for direct connection with left hand bus bar.
API No.
16 -bit
instruction
32 -bit
instruction
Continuity
condition
Discontinuity
condition
224
LD＝ DLD＝ S
1
＝S
2
S
1
≠S
2
225
LD＞ DLD＞ S
1
＞S
2
S
1
≦S
2
226
LD＜ DLD＜ S
1
＜S
2
S
1
≧S
2
228
LD＜＞ DLD＜＞ S
1
≠S
2
S
1
＝S
2
229
LD＜＝ DLD＜＝ S
1
≦S
2
S
1
＞S
2
230
LD＞＝ DLD＞＝ S
1
≧S
2
S
1
＜S
2
3. When the MSB (16-bit instruction: b15, 32-bit instruction: b31) of S
1
and S
2
is 1, the
comparison value will be viewed as a negative value in comparison.
4. When 32-bit counters (C200 ~ C254) are used in this instruction, make sure to adopt 32-bit
instruction (DLD※). If 16-bit instruction (LD※) is adopted, a “program error” will occur and the
ERROR indicator on the MPU panel will flash.
Program Example:
1. When the content in C10 = K200, Y20 = ON.
2. When the content in D200 > K-30 and X1 = ON, Y21 = ON and latched.
LD=
K200 C10
Y20
LD<=
D200 K-30
X1
SET
Y21
