This version adds support for AxisGroup objects.

This version can only be installed if no older versions (before November 2025) of several add-ons are installed:

• No old setup add-ons: CODESYS Communication, Visualization, Ethernet IP, Application Composer.
• No old optional add-ons: CODESYS ControlElement Library, IIoT Libraries, OPC UA Client API.
• No CODESYS OPC UA Pub/Sub before 1.4.0.0 (release not yet scheduled).

Reason: It cuts dependencies on CAA libraries. This introduces an incompatibility where user-defined data types are used in Element Collections (they now need to implement MBM.IDisposable).

Additionally it includes fixes for multi casting (Net Base Services) and online change (Element Collections), and provides an updated library project template.

This version introduces the new File_and_Dir library for synchronous and asynchronous file and folder operations which improve on CAA File (going into service phase) and SysFile/SysDir.

This release introduces a new file-based storage format for CODESYS CFC Editor. The new format makes your CFC data easier to store, manage, and integrate into modern, file-oriented workflows.

This release also includes several bug fixes that improve overall stability.

Fixes sporadic issues with the atomicity of the TEST_AND_SET operator.

Maintenance release Fixes sporadic issues with the atomicity of the TEST_AND_SET operator.

Enable usage of codegenerators for ARM architecture in CODESYS 4

Support for the RISC-V 64-bit CPU Architecture.

What is CODESYS 4?

Web-based, platform-independent next-generation engineering tool for IEC 61131-3. Complements CODESYS 3.

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Key Capabilities

Browser-based (independent of the operating system), text-based projects ready for version control, command line (CLI) - automation (CI/CD) out of the box, ST and Ladder editors, Modbus I/O configuration.

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Webinars

• CODESYS 4: Motivation and background for the new web-based IDE for PLCs (Part 1)
• CODESYS 4: How to benefit today (Part 2)

Service packs for CODESYS V3 are released at annual intervals and include numerous improvements and bug fixes.

This version contains bug fixes in various product areas.

This version contains bug fixes in various product areas.

Version 4.0.0.0 of CODESYS Control RTE SL is the first release provided independently of the IDE and is based on V3.5.100.0 of the CODESYS Runtime Toolkit.

The main new feature is the double-buffered retain mechanism, which guarantees consistent retain data in the event of a controller failure like powerfail.

CODESYS Control SL Release based on CODESYS V3.5 SP22 Patch 3

This version contains several bugfixes and improvements.

Add the possibility for SDK customers to add custom tools the MCP Server.

Version 4.5.0.0 is a maintenance release focused on correctness and usability in the safety editor.

The main change is a fix to the TON timer behavior on EL6900 and EL6910: the configured time was previously extended by one time base (1 ms or 10 ms) and now matches the configured value.

Behavioral change — projects that compensated for the previous offset should be reviewed.

The release also resolves two online-mode issues:

• Monitoring initialization could enter an endless loop in certain multi-application setups and block the UI.
• An inefficient monitoring callback slowed UI responsiveness in projects with a large process image.

In addition, example projects are no longer shipped with the package, and the end-user documentation was cleaned up.

This version contains bug fixes, improvements and the following new features:

• support for Beckhoff MX system
• support for Balluff IO-Link gateways BNI XG1, XG3 and XG5
• improvements, when used together with CODESYS Redundancy

Beside bug fixes and improvements this version will contain the following feature:

• UI configurator support to add, delete and edit connections.

First Stable Release (following 0.9 preview)

Highlights of this release:

• New file format – cleaner structure, easier to diff
• Normalized line endings for reliable Git operations across platforms
• UX refinements aligned with CODESYS SP22
• Compatible with CODESYS Git V2.0.0.0
• Improved Scripting driver
• Read-Only Mode – usable without a license

Designed for file-based project workflows in CODESYS Development System.

New major version of the Git Integration which works directly on top of a CODESYS file based storage project. This means that human readable project representation is available by default enabling new use cases for our git Integration.

This version provides a new Web Client library using modern Strings (STRLIB) and supporting the content-type "multipart/form-data".

This version contains several bug fixes and improvements for the installation process. Users can now select required packages directly from their local hard drive, ensuring a smooth and complete installation even when the deployment server is missing components.

Maintenance version.

Highlights of this release:

• Customizable toolbox – add your own items and access frequently used blocks directly
• Improved parallel branches – insert markers on hover, clearer parallel insert commands, new Show Insert Positions toggle (Ctrl+Shift+M), plus several reliability fixes for closing branches
• EN/ENO compile fixes – MOVE and operator boxes (ADD, AND, MUL, OR, SEL, SUB, XOR) with EN but without ENO now compile as expected (relevant after LDFBD → LD2 conversion)
• Editor fixes – Unicode/CJK variable names no longer truncated; negated contacts colored correctly in online view; accurate error locations on NC contacts and transitions; connected inputs and outputs preserved on FB type change
• Stability – crash on block type change, Project Compare Allow Single exception, and cross-reference list freeze all resolved
• Hardened PLCopenXML import/export – FBs without EN/ENO pins, edge-detection modifiers, schema ordering issues
• File-Based Storage support for LD2 POUs (requires SP22 + File-Based Storage 1.0.0.0)

This version includes bug fixes.

This version will contain bug fixes, improvements and the following new features:

• Support for online change for Modbus Client in context of CODESYS Online Configuration Change

This version improves the handling of problems with subscriptions on the server side: access to subscription status codes; error code for rejected subscription.

This version adds support for resolution of namespaces URI (to server-specific changable IDs)

This version makes OPC UA PubSub available for CODESYS 4. And it allows the installation of CODESYS Base Libraries version 5.0.

Maintenance version.

This version will contain bug fixes, improvements and the following new features:

• Topology Editor that displays graphically all involved devices and its connections.

• Dynamic Reconfiguration to support online change when modifying/adding devices.

• Support of GSDML specification V2.46

• Show newest installed device only

  • Per default, no more duplicates / older versions of a device are shown.

• SysEthernetBurst

  • Use new runtime interface (included in SP22) that sends and receives multiple Ethernet frames with one call.
  • Noticeable performance improvement.

Maintenance version.

Version 3.5.100.0 of the CODESYS Runtime Toolkit is the first release that is provided independently of the IDE. It can be programmed with all maintained IDE versions.

All runtime-system-dependent IEC libraries (System Libraries) have been moved into a Runtime AddOn that can be installed onto any supported IDE.

Beside that, this version also includes minor improvements and several bug fixes.

Version 4.3.0.0 of CODESYS Safe Control Core introduces two key changes.

With ARM 64 bit support, Safe Control Core and derived products such as Virtual Safe Control SL can now be executed on ARM-based target devices in addition to the previously supported architectures. The runtime has been migrated to the CODESYS V3.5 SP22 branch, which receives security updates for six years and thus provides a long-term stable base aligned with CRA requirements.

Together, these changes extend integration capabilities, broaden hardware coverage, and secure the long-term maintainability of Safe Control Core–based products.

Version 4.4.0.0 of the CODESYS Safe Control Core introduces an external POU Interface that enables the development of custom function blocks in ANSI C, including floating-point operations.

In addition, a new interface allows the second independent timer to be queried from a local second time source instead of a second device.

Finally, the safe network variables already available in the Runtime SDK are now released for Safe Control Core as well.

Together, these features expand the range of safety application development, simplify the hardware setup for time monitoring, and extend safe communication capabilities.

Version 4.5.0.0 of the CODESYS Safety Extension introduces support for signed and compiled IEC libraries in safety projects, as well as internal safety libraries. Own function blocks can now be bundled into a library, significantly simplifying the reuse of pre-certified function blocks. These changes are complemented by bug fixes and usability improvements.

This version will increase the usability based on user feedback and will include a few Bug-fixes.

This version contains several Improvements and Bug fixes. For example the usablility will be improved by enablling the horizontal scrolling with the mouse wheel.

The Simulation Interface integrates CODESYS applications into machine simulations (Software-in-the-loop) by a toggle switch using OPC UA mechanisms (machine simulation requires compliant connector).

This version brings support for MC_MovePath, which allows to use the G-Code processing from SoftMotion CNC to move an axis group from SoftMotion Robotics.

The CNC additional axes A/B/C and P/Q/U/V/W have been improved and can now all be interpolated linearly, cubically, or quinitically.

The CNC ellipses as well as SMC_AvoidLoop have been extended to support arbitrary planes.

New library implementing the SRCI interface for commanding robots of various vendors.

Enables the usage of the Test Manager in noUI mode for CI/CD workflows.

Besides some bug fixes and improvements this version contains a new readable textual format for visualizations.