Attention

IronPLC can only run very simple programs. The steps described are accurate but many language features are not yet supported.

VariablesΒΆ

Variables in IEC 61131-3 are declared in blocks within program organization units. This section covers the declaration syntax, qualifiers, and scoping rules.

Topic

Description

Status

Variable Declarations

Variable declaration blocks

Supported

I/O Qualifiers

Direct addressing (%I, %Q, %M)

Partial

Variable Scope

Variable scope keywords

Partial

Retention

Retention and constant qualifiers

Not yet supported

Initial Values

Variable initialization

Supported