Floating-Point Numbers (F, Df) - Delta AH Series Operation Manual

AH Mo t io n C on tr o ll er – O p er a t io n M a nu a l
The hexadecimal number in the PLC is used as;
 the constant 16#: It is used as the operand in the applied instruction. For example, MOV 16#1A2B D0
(hexadecimal constant).

5.2.17. Floating-point Numbers (F, DF)

The floating-point numbers are represented by decimal points in ISPSoft. For example, the floating-point number of 500 is
500.0.
 Single-precision Floating-point Numbers
The floating-point number is represented by the 32-bit register. The representation adopts the IEEE754 standard, and
the format is as follows.
8 -b it
S
E xpo ne nt
b
31
S ig n b it
0 : Po siti ve
1 : Neg ati ve
( )
−
1
Equation:
The single-precision floating-point numbers range from ±2
-38
±1.1755×10
The AH500 series PLC uses two consecutive registers to form a 32-bit floating-point number. Take (D1, D0) for
example.
_5
2 2
S E7 E6
b31 b30 b29 b28
E xp on en t ( 8 b its )
Ma nt iss a s ign b it (0 : Po s it iv e; 1: Ne ga tiv e)
W hen b 0~ b3 1 a re z eros , t he c on te nt is z ero .
 Double-precision Floating-point Numbers
The floating-point number is represented by the 64-bit register. The representation adopts the IEEE754 standard, and
the format is as follows.
11- bi t
S
E xpo ne nt
b
63
S ig n b it
0 : Po siti ve
1 : Neg ati ve
5 - 1 2
2 3- bi t
Ma nti ssa
−
× × =
S
E B
2 . 1 M ; B 127
+38
to ±3.4028×10 .
D1 (b 15 ~b 0)
2 2 2 2 2
E5 E1 E0 A22 A21 A20
b24 b23 b22 b21
T he pos ition w here the d eci mal point is hid den
5 2- bi t
Ma nti ssa
b
0
-126
to ±2
D0 (b 15 ~b 0)
2 2 2 2 2
A6 A5 A4 A3 A2
b20 b6 b5 b4 b3
Ma nt iss a (2 3b it s )
b
0
+128
, and correspond to the range from
2 2 2
A1 A0
b2 b1 b0