Omron SYSMAC CJ - REFERENCE MANUAL 08-2008 User Manual

606
Floating-point Math Instructions Section 3-15
Description *F(456) multiplies the 32-bit floating-point number in Md+1 and Md by the 32-
bit floating-point number in Mr+1 and Mr and places the result in R+1 and R.
(The floating point data must be in IEEE754 format.)
If the absolute value of the result is greater than the maximum value that can
be expressed as floating-point data, the Overflow Flag will turn ON and the
result will be output as
±∞.
If the absolute value of the result is less than the minimum value that can be
expressed as floating-point data, the Underflow Flag will turn ON and the
result will be output as 0.
The various combinations of multiplicand and multiplier data will produce the
results shown in the following table.
Note 1. The results could be zero (including underflows), a numeral, +
∞, or –∞.
2. With CJ1H-CPU@@H-R CPU Units, an undetermined value will be output.
3. The Error Flag will be turned ON and the instruction will not be executed.
Flags
Precautions The Multiplicand (Md+1 and Md) and Multiplier (Mr+1 and Mr) data must be in
IEEE754 floating-point data format.
Multiplicand
Multiplier 0 Numeral +∞ –∞ NaN
0 0 0 See note 3. See note 3.
Numeral 0 See note 1. +/–∞
(See note 2.)
+/–∞
(See note 2.)
+∞ See note 3. +/–∞
(See note 2.)
+∞ –∞
–∞ See note 3. +/–∞
(See note 2.)
–∞ +∞
NaN See note 3.
R+1
R
Md
Multiplicand (floating-point data, 32 bits)
Md+1
Mr
Multiplier (floating-point data, 32 bits)
Mr+1
Result (floating-point data, 32 bits)
×
Name Label Operation
Error Flag ER ON if the multiplicand or multiplier data is not recognized
as floating-point data.
ON if the multiplicand or multiplier is not a number (NaN).
ON if +∞ and 0 are multiplied.
ON if –∞ and 0 are multiplied.
OFF in all other cases.
Equals Flag = ON if both the exponent and mantissa of the result are 0.
OFF in all other cases.
Overflow Flag OF ON if the absolute value of the result is too large to be
expressed as a 32-bit floating-point value.
Underflow Flag UF ON if the absolute value of the result is too small to be
expressed as a 32-bit floating-point value.
Negative Flag N ON if the result is negative.
OFF in all other cases.

Omron SYSMAC CJ - REFERENCE MANUAL 08-2008 Specifications

General

Brand	Omron
Model	SYSMAC CJ - REFERENCE MANUAL 08-2008
Category	Controller
Language	English