Fnc121 - Esub / Floating Point Subtraction - Mitsubishi Electric FX3G SERIES Programming Manual

FX /FX /FX Series Programmable Controllers
3G 3U 3UC
Programming Manual - Basic & Applied Instruction Edition
18.9 FNC121 – ESUB / Floating Point Subtraction
Outline
This instruction executes subtraction of two binary floating point data.
1. Instruction format
FNC 121
D P
ESUB
2. Set data
Operand Type
S
1
S
2
D
*1. When a constant (K or H) is specified, it is automatically converted into binary floating point (real number)
when the instruction is executed.
3. Applicable devices
Bit Devices
Oper-
and System User
Type
X Y M T C S D .b KnX KnY KnM KnS T C D R U \G
S
1
S
2
D
: This function is supported only in FX
Explanation of function and operation
1. 32-bit operation (DESUB and DESUBP)
Binary floating point data [
subtraction result in the binary floating point format is transferred to [
Command
input
FNC121
DESUB
When a constant (K or H) is specified as [
binary floating point.
Command
input
FNC121
DESUB
Caution
1. When the same device is specified
The same device number can be specified in [
In this case, note that the subtraction result changes in every operation cycle when the continuous operation type
instruction (DESUB) is used.
→ For program examples of floating point operations, refer to Section 12.10.
Mnemonic
16-bit Instruction
−
Word device number storing binary floating point data used in subtraction
Word device number storing binary floating point data used in subtraction
Data register number storing the subtraction result
Digit Specification
/FX
3U 3UC
S +1, S ] is subtracted from binary floating point data [
2 2
S S D
1 2
S
1
S S D
1 2
S
18 Floating Point – FNC110 to FNC139
18.9 FNC121 – ESUB / Floating Point Subtraction
→ For handling of floating point, refer to Subsection 5.1.3.
→ For flag operations, refer to Subsection 6.5.2.
Operation Condition
32-bit Instruction
13 steps
Description
Word Devices
Special
System User Index
Unit
V Z Modify K H
PLCs.
D +1,
] − [
S S S
[ +1,
1 1 2
Binary floating point Binary floating point
+1, S ] or [ S +1, S
1 2
] − [
[ S +1, S
1 1
Binary floating point Automatically
converted into binary
floating point
+1, S ],[ S +1, S
1 1 2
Mnemonic Operation Condition
Continuous
DESUB
Operation
Pulse (Single)
DESUBP
Operation
Data Type
Real number (binary)
Others
Con- Real Charac-
stant Number ter String
E " "
S +1, S
1 1
D ].
] → [
S D D
+1, +1,
2
Binary floating point
], it is automatically converted into
2
] → [
K2346 D +1, D
Binary floating point
] and [ D +1, D ].
2
11
12
13
14
*1
15
Pointer
P
16
17
], and the
18
]
19
]
20
507