FX
/FX
/FX
Series Programmable Controllers
3G
3U
3UC
Programming Manual - Basic & Applied Instruction Edition
18.13 FNC125 – LOGE / Floating Point Natural Logarithm
Outline
This instruction executes the natural logarithm operation.
1. Instruction format
FNC 125
D
LOGE
2. Set data
Operand Type
S
D
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
D
Explanation of function and operation
1. 32-bit operation (DLOGE and DLOGEP)
Natural logarithm [logarithm whose base is "e (2.71828)"] of [
is stored to [
D
Command
input
FNC125
DLOGE
• Only a positive value can be set in [
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.
• When a negative value is specified in
• When "0" is specified in
512
Mnemonic
16-bit Instruction
P
−
−
Head device number storing binary floating point data used in the natural logarithm
operation
Head device number storing the operation result
Digit Specification
+1,
D
]. A real number can be directly specified as
S
D
S
S
(error code: K6706)
S
18.13 FNC125 – LOGE / Floating Point Natural Logarithm
→ For handling of floating point, refer to Subsection 5.1.3.
Operation Condition
32-bit Instruction
Description
Word Devices
Special
System User
Unit
S
+1,
+1
S
S
log
e
Binary floating point
(real number)
+1,
]. (The natural logarithm operation cannot be executed for a
S
(error code: K6706)
18 Floating Point – FNC110 to FNC139
Mnemonic
Operation Condition
DLOGE
9 steps
DLOGEP
Real number (binary)
Others
Con-
Real
Index
stant
Number
V
Z Modify K H
E
S
] is calculated, and the operation result
S
.
+1
D
Binary floating point
(real number)
Continuous
Operation
Pulse (Single)
Operation
Data Type
Charac-
Pointer
ter String
" "
P
D