Omron SYSMAC CJ - REFERENCE MANUAL 08-2008 Reference Manual page 648

Floating-point Math Instructions
Description
Note
Flags
Precautions
608
/F(457) divides the 32-bit floating-point number in Dd+1 and Dd by the 32-bit
floating-point number in Dr+1 and Dr and places the result in R+1 and R. (The
floating point data must be in IEEE754 format.)
Dd+1
Dr+1
R+1
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 dividend and divisor data will produce the results
shown in the following table.
Multiplier 0
0 See note 4.
Numeral 0
+ 0
– 0
NaN
1. The results will be zero for underflows.
2. The results could be zero (including underflows), a numeral, + , or – .
3. With CJ1H-CPU@@H-R CPU Units, an undetermined value will be output.
4. The Error Flag will be turned ON and the instruction will not be executed.
Name Label
Error Flag ER
Equals Flag =
Overflow Flag OF
Underflow Flag UF
Negative Flag N
The Dividend (Dd+1 and Dd) and Divisor (Dr+1 and Dr) data must be in
IEEE754 floating-point data format.
Dividend (floating-point data, 32 bits)
Dd
Divisor (floating-point data, 32 bits)
Dr
Result (floating-point data, 32 bits)
R
.
Multiplicand
Numeral +
+/– +
(See note 3.) (See note 3.)
See note 2. +/–
0 (See notes See note 4.
1 and 3.)
0 (See notes See note 4.
1 and 3.)
Operation
ON if the dividend or divisor data is not recognized as
floating-point data.
ON if the dividend or divisor is not a number (NaN).
ON if the dividend and divisor are both 0.
ON if the dividend and divisor are both + or – .
OFF in all other cases.
ON if both the exponent and mantissa of the result are 0.
OFF in all other cases.
ON if the absolute value of the result is too large to be
expressed as a 32-bit floating-point value.
ON if the absolute value of the result is too small to be
expressed as a 32-bit floating-point value.
ON if the result is negative.
OFF in all other cases.
Section 3-15
– NaN
–
(See note 3.)
+/–
See note 4.
See note 4.
See note 4.