# CODESYS ASIN

Instructions · `ASIN` · verification: source checked

ASIN is an IEC operator in the CODESYS Development System that yields the arcsine value of a number. The input variable can be any numeric basic data type, and the output is returned as REAL or LREAL. The document's example is q := ASIN(0,5); which gives the result 0.523599.

## Specification

| Property | Value |
|---|---|
| Language | structured text |
| Code | ASIN |
| Syntax | q := ASIN(0,5); |
| Dialect | CODESYS |

## Study notes

- Permitted data types for input variables: any numeric basic data type.
- Permitted data types for output variables: REAL and LREAL.
- Example shown in ST: q := ASIN(0,5); with the result in q equal to 0.523599.
- The operator is also illustrated in FBD form.
- The document does not state parameter names for the input or output variables; it only refers to input variables and output variables.

## Sources

1. [Beckhoff Information System](https://infosys.beckhoff.com/content/1033/tc3_plc_intro/2529144203.html) (accessed 2026-10-26)
2. [CODESYS Group](https://content.helpme-codesys.com/en/CODESYS%20Development%20System/_cds_operator_asin.html) (accessed 2026-10-26)

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Source page: https://machineschema.com/instruction/iec-asin  
JSON: https://machineschema.com/instruction/iec-asin.json  
License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite Machine Schema and the original sources.