Mitsubishi Electronics FX3UC ユーザーズマニュアル
511
FX
3S
/FX
3G
/FX
3GC
/FX
3U
/FX
3UC
Series
Programming Manual - Basic & Applied Instruction Edition
18 Floating Point – FNC110 to FNC139
18.13 FNC125 – LOGE / Floating Point Natural Logarithm
11
FN
C30
-FN
C3
C30
-FN
C3
9
R
ota
tion and
Shi
ft
ft
12
FN
C40-FN
C40-FN
C49
D
ata O
perati
perati
on
13
FNC
50-FNC
59
High-Speed
Proc
essing
14
FM
C60-FN
C60-FN
C69
H
andy
In
struction
15
FN
C70-FN
C70-FN
C79
E
xternal
F
X
I/O
De
vice
16
FNC
80-FNC
89
External
FX
Dev
ice
ice
17
FNC1
00-
FNC10
00-
FNC10
9
Dat
a
a
Transfer 2
18
FNC1
10-
FNC139
FNC139
Fl
oati
ng Poi
nt
19
FNC14
0-F
N
C
149
Da
ta
Operation 2
20
FNC1
50-
FNC159
FNC159
Pos
itioning
itioning
Control
18.13 FNC125 – LOGE / Floating Point Natural Logarithm
Outline
This instruction executes the natural logarithm operation.
→ For handling of floating point, refer to Subsection 5.1.3.
1. Instruction format
2. Set data
3. Applicable devices
Explanation of function and operation
1. 32-bit operation (DLOGE and DLOGEP)
Natural logarithm [logarithm whose base is "e (2.71828)"] of [
+1,
] is calculated, and the operation result
is stored to [
+1,
]. A real number can be directly specified as
.
• Only a positive value can be set in [
+1,
]. (The natural logarithm operation cannot be executed for a
negative value.)
Errors
An operation error is caused in the following cases; The error flag M8067 turns ON, and the error code is stored in
D8067.
D8067.
• When a negative value is specified in
(error code: K6706)
• When "0" is specified in
(error code: K6706)
Operand Type
Description
Data Type
Head device number storing binary floating point data used in the natural logarithm
operation
operation
Real number (binary)
Head device number storing the operation result
Oper-
and
Type
Bit Devices
Word Devices
Others
System User
Digit Specification
System User
Special
Unit
Index
Con-
stant
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
P
FNC 125
LOGE
D
−
−
−
Mnemonic
Operation Condition
16-bit Instruction
DLOGE
DLOGEP
Mnemonic
Operation Condition
32-bit Instruction
9 steps
Continuous
Operation
Pulse (Single)
Pulse (Single)
Operation
S
D
S
D
S
S
D
D
S
Command
input
FNC125
DLOGE
S
D
+1
Binary floating point
(real number)
+1
Binary floating point
(real number)
log
e
S
S
D
D
S
S
S
S