Omron CS1G/H-CPUxxH Instructions Manual page 568

Floating-point Math Instructions
Description
Flags
Precautions
ACOS(464) computes the angle (in radians) for a cosine value expressed as a
32-bit floating-point number in S+1 and S and places the result in R+1 and R.
(The floating point source data must be in IEEE754 format.)
–1
COS S+1
R+1
The source data must be between –1.0 and 1.0. If the absolute value of the
source data exceeds 1.0, an error will occur and the instruction won't be exe-
cuted.
The result is output to words R+1 and R as an angle (in radians) within the
range of 0 to π .
The following diagram shows the relationship between the input data and
result.
Name Label
Error Flag ER
Equals Flag =
Overflow Flag OF
Underflow Flag UF
Negative Flag N
The source data in S+1 and S must be in IEEE754 floating-point data format.
Source (32-bit floating-point data)
S
Result (32-bit floating-point data)
R
S: Input data (cosine value)
R
R: Result (radians)
Operation
ON if the source data is not recognized as floating-point
data.
ON if the source data is not a number (NaN).
ON if the absolute value of the source data exceeds 1.0.
OFF in all other cases.
ON if both the exponent and mantissa of the result are 0.
OFF in all other cases.
OFF
OFF
ON if the result is negative.
OFF in all other cases.
Section 3-15
547