365
Floating-point Math Instructions
Section 5-24
Flags
ER:
Indirectly addressed EM/DM word is non-existent.
(Content of
*
EM/
*
DM word is not BCD, or the EM/DM area boundary
has been exceeded.)
ON if the source data is not recognized as floating-point data.
ON if the absolute value of the source data exceeds 65,535.
EQ:
ON if both the exponent and mantissa of the result are 0.
5-24-14 ARC SINE: ASIN(––)
Limitations
The source data in S+1 and S must be in IEEE754 floating-point data format.
DM 6143 to DM 6655 cannot be used for R.
Description
ASIN(––) calculates the arc sine of a 32-bit floating-point number and places
the result in the specified result words. (The arc sine function is the inverse of
the sine function; it returns the angle that produces a given sine value
between –1 and 1.)
When the execution condition is OFF, ASIN(––) is not executed. When the
execution condition is ON, ASIN(––) computes the angle (in radians) for a
sine 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.)
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 –
π
/2 to
π
/2.
S
:
First source word
IR, SR, AR, DM, EM, HR, TIM/CNT, LR
R
:
First result word
IR, SR, AR, DM, EM, HR, LR
Ladder Symbols
Operand Data Areas
Third operand
:
Always 000
−−−
ASIN(
−−
)
S
R
000
@ASIN(
−−
)
S
R
000
R+1
R
S
Source (32-bit floating-point data)
S+1
Result (32-bit floating-point data)
SIN
–1
