Attention

IronPLC implements many parts of the IEC 61131-3 standard and is working toward full Structured Text support. Key features still missing include ranges, enum and I/O mapping.

Extension Library

IronPLC provides vendor extension functions, function blocks, and variables that go beyond the IEC 61131-3 standard. These extensions are commonly supported by other PLC environments such as CODESYS, TwinCAT, and RuSTy.

Tip

Extension library items require explicit opt-in via --allow-* flags or --dialect rusty. See Enabling Dialects and Features for details.

Functions

Function

Description

SIZEOF

Size in bytes of a variable or type (requires --allow-sizeof)

Function Blocks

No vendor extension function blocks are currently defined.

Variables

Variable

Description

__SYSTEM_UP_TIME / __SYSTEM_UP_LTIME

Monotonic uptime since VM start (requires --allow-system-uptime-global)