538 Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Chapter 14 Trigonometric Instructions (SIN, COS, TAN, ASN, ASIN, ACS, ACOS, ATN, ATAN)
Arc Sine (ASN)
The ASN instruction takes the arc sine of the Source value and stores the result in
the Destination (in radians).
Operands:
Relay Ladder
Structured Text
Use ASIN as a function. This function computes the arc sine of source and stores
the result in dest.
See Structured Text Programming
for information on the syntax of expressions
within structured text.
Function Block
FBD_MATH_ADVANCED Structure
Description: The Source must be greater than or equal to -1 and less than or equal to 1. The
resulting value in the Destination is always greater than or equal to -Ï€/2 and less
than or equal to π/2 (where π = 3.141593).
Arithmetic Status Flags: Arithmetic status flags are affected.
Operand Type Format Description
Source SINT
INT
DINT
REAL
Immediate
Tag
Find the arc sine of this value
Destination SINT
INT
DINT
REAL
Tag Tag to store the result
Operand Type Format Description
ASN tag FBD_MATH_ADVANCED Structure ASN structure
Input Parameter Data Type Description
EnableIn BOOL Enable input. If cleared, the instruction does not execute and outputs are not updated.
Default is set.
Source REAL Input to the math instruction.
Valid = any float
Output Parameter Data Type Description
EnableOut BOOL The instruction produced a valid result.
Dest REAL Result of the math instruction. Arithmetic status flags are set for this output.