What happens to a three-segment address such as %I0.1.0?

The training runtime models one rack, so it discards the rack segment and maps the address to %I1.0. That is a simulator design boundary, not a general Control Expert rule.

Is Unity Pro the same as EcoStruxure Control Expert?

Control Expert is the current name in the Schneider engineering-software lineage formerly known as Unity Pro. Existing plants and training material may use either name.

Does this page cover EcoStruxure Machine Expert?

Not as a project environment. Machine Expert and Machine Expert Basic target different Schneider controller families. This parser is scoped to Unity/Control Expert-style IL plus documented Modicon address forms.

Can this open a Control Expert project?

No. It accepts text examples for learning and does not import, export or download Control Expert projects.

Schneider PLC Programming — Modicon Simulator

Two address traditions appear in Schneider maintenance work

Unity Pro and EcoStruxure Control Expert projects use IEC-style located variables, including rack/module/bit forms such as %I0.1.0. Older Modicon material may use reference families such as 0:00001, 1:00001 and 4:00001.

The browser parser accepts both forms so learners can practise translating existing logic. It models one training rack and therefore collapses the rack segment rather than reproducing a complete Modicon hardware configuration.

Schneider’s software family matters: Machine Expert and Machine Expert Basic serve different machine-controller ranges from Control Expert. The parser documented here targets the Unity/Control Expert IL and Modicon addressing context, not every Schneider controller under one label.

Address translation sheet

Read the memory map before the rung

These are the address forms this learning runtime recognises. The final column states the simulator behavior, including intentional simplifications.

Device / area	Role	Example	Browser behavior
%I / %Q	Located IEC I/O	%I0.1.0, %Q0.0.0	Three segments collapse to module.bit because the training runtime models one rack.
0:	Legacy discrete input	0:00001	Converts a one-based Modicon reference to runtime input memory.
1:	Legacy discrete output	1:00001	Converts to the matching runtime output bit.
4:	Holding register	4:00001	Maps the one-based reference to %MW0.
%M / %MW	Internal bit / word	%M0.0, %MW0	Runs as native internal memory in the training engine.

Executable now

Supported instruction groups

IEC IL logic: LD, LDN, AND, ANDN, OR, ORN and NOT
Grouping: AND(, OR( and closing parenthesis
Outputs and latches: ST, STN, S and R
Address translation: IEC two/three-segment and Modicon 0:/1:/4: forms

Do not assume

Not in the current subset

%KW constant words
Complete Unity/Control Expert instruction and function-block libraries
Multiple racks, module configuration and device communication
Safety PLC behavior, process I/O fidelity and production commissioning

Choose the right simulator

Browser practice vs official engineering simulation

Both are useful, but they answer different questions. Start here to make the logic observable; use the vendor environment to validate a real controller project.

Decision	This browser simulator	Official vendor environment
Primary job	Learn syntax and scan behavior quickly	Engineer a project for a selected controller
Runtime scope	The exact subset published on this page	Controller- and version-specific implementation
Project format	Text exercises inside the training app	Native vendor project, libraries and configuration
Hardware transfer	Not supported	Upload, download and online diagnostics

Worked example

A legacy Modicon start/stop output

The parser translates the one-based 0: input references and 1: output reference into the training I/O bus before execution.

Run your own program

Schneider / Modicon ILParser-valid example

(* 0:00001 = start, 0:00002 = stop *)
LD    0:00001
ANDN  0:00002
ST    1:00001

Learning sequence

Practise the translation, then the logic

01
Identify the address family
Separate located IEC variables from legacy Modicon references before editing.
02
Normalise one rung
Translate the input and output points, then follow LD/ANDN/ST.
03
Add grouping and state
Practise parenthesised branches plus S/R behavior in small programs.
04
Validate in Control Expert
Configure the real rack, modules, tasks and controller-specific instructions.

Engineering boundary

A syntax-and-logic simulator, not Control Expert

This page supports learning and legacy-code interpretation. It does not emulate a Modicon CPU, Unity project, rack, fieldbus or safety execution environment.

The first rack segment is deliberately discarded by the one-rack training runtime.
%KW constant words are rejected instead of approximated.
Use official tools and hardware tests for every production decision.

Technical evidence

Sources and verification

Page claims and the simulator support matrix were reviewed against the production parser and these primary technical sources on 24 July 2026.

Continue through the cluster

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PLC programming simulator

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Questions

Schneider PLC Programming and Modicon Simulator FAQ

Yes. The parser accepts those legacy input, output and holding-register references and maps them into the training runtime.

Practise Schneider and Modicon address translation

Run a small IL program, inspect the mapped I/O, and build confidence before touching a controller project.

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