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Updated 2025-11-10
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Pointer

Pointer

Variable storing memory address of another variable for indirect addressing.

Key Takeaways

  • Variable storing memory address of another variable for indirect addressing.
  • Advanced-level topic in Data Types & Variables
  • Related to: Array, Data Block, BOOL

Detailed Definition

Variable storing memory address of another variable for indirect addressing. This term is essential for understanding data types in industrial automation and PLC programming.

Pointer is part of the type system defined by IEC 61131-3, the international standard for PLC programming languages. Variable storing memory address of another variable for indirect addressing.

Type selection has knock-on effects throughout the project: HMI tag bindings, data-block organisation, communication-record sizes, and historian storage are all influenced by the underlying type. Get the type right early — fixing it later is a cross-cutting refactor.

For commissioning engineers, the most reliable diagnostic with Pointer is to inspect the variable in the IDE's online watch table while toggling related inputs — type-mismatch bugs are caught faster by direct observation than by reading code.

Common Questions

What is Pointer?

Variable storing memory address of another variable for indirect addressing.

What prerequisites are needed to understand Pointer?

As an advanced-level concept, Pointer requires a solid foundation in PLC fundamentals and intermediate programming concepts. It's recommended to have hands-on experience with Data Types & Variables before diving deep into this topic.

What are related concepts I should learn?

To fully understand Pointer, you should also familiarize yourself with Array, Data Block, and BOOL. These concepts work together in industrial automation systems.

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Quick Info

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About Data Types & Variables

Data structures, variable types, and memory organization

Total Terms:30
Difficulty:Beginner to Intermediate

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