490
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
18 Floating Point – FNC110 to FNC139
18.15 FNC127 – ESQR / Floating Point Square Root
18.15 FNC127 – ESQR / Floating Point Square Root
Outline
This instruction obtains the square root of binary floating point.
→
For handling of floating point, refer to Subsection 5.1.3.
1. Instruction format
2. Set data
*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
Explanation of function and operation
1. 32-bit operation (DESQR and DESQRP)
The square root of [
+1,
] is calculated (in the binary floating point operation), and the result is
transferred to [
+1,
].
Related device
→
For the zero flag use method, refer to Subsection 6.5.2.
Error
The contents of [
+1,
] are valid only when a positive value is set. When a negative value is set,
the operation error flag M8067 turns ON, and the instruction is not executed.
Operand Type
Description
Data Type
Word device number storing binary floating point data whose square root is
calculated
Real number
(binary)
*1
Data register number storing the square root of binary floating point data
Oper-
and
Type
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
3 3
3
3
3 3
3
3 3
3
3
Device
Name
Description
M8020
Zero flag
Turns ON when the operation result is true "0".
−
Mnemonic
Operation Condition
16-bit Instruction
DESCR
DESCRP
Mnemonic
Operation Condition
32-bit Instruction
9 steps
Continuous
Operation
Pulse (Single)
Operation
P
FNC 127
ESQR
D
S
D
S
D
S
1
S
1
D
D
Command
input
FNC127
DESQR
→
[ +1, ]
Binary floating point
[ +1, ]
Binary floating point
S
D
S
D
S
D
S
1
S
1