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UML Code Generation for Embedded Systems

Embedded UML RXF is the runtime framework between your UML model and your target hardware. It implements UML constructs with no C/C++ equivalent, manages RTOS integration through swappable adapters, and generates production code, without compromising your application model.

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PRODUCT OVERVIEW

What is Embedded UML RXF?

Embedded UML Real-time eXecution Framework (RXF) is the interface between a UML model and the target platform. It acts as a translation layer between the expressive world of UML modeling and the constraints of embedded C/C++ development, enabling teams to work at the model level without ever sacrificing code efficiency or target compatibility.

At its core, RXF is a library and runtime environment that implements all UML elements including constructs like Active Classes, state machines, and event queues, that have no direct equivalent in C or C++. It integrates into IBM Rhapsody and handles target-specific RTOS calls through a set of ready-to-use adapters, keeping your application model clean and entirely portable.

The result: you model the best possible solution, and RXF generates production-ready code that runs efficiently on your target whether that's a high-end microprocessor or a resource-constrained embedded controller with no RTOS at all.

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Complete UML-to-C/C++ implementation

RXF provides a full library of C/C++ implementations for UML constructs including Active Classes, hierarchical state machines, synchronous and asynchronous messaging, and event queues. Your model is not constrained by what the language can express natively.

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Nothing but the UML model

A UML model often includes elements or constructs that are specific to the RTOS and target environment or that work around C/C++ language constraints. Embedded UML RXF encapsulates all environment-specific items in adapters to give you a more concise application model. A built-in library facilitates the use of model elements with no equivalent in C/C++. Your UML model stays clean, and concise and can easily be ported to other target systems just by selecting the appropriate adapters.

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Unlock the potential of your IBM Rhapsody environment

Embedded UML RXF adds more value to your IBM Rhapsody environment. The Framework includes everything you need to be able to focus your creativity on the solution rather than cumbersome adaption details. Debug your UML model on the target, minimize customization efforts with our target adapters, and rely on our C/C++ libraries to include the appropriate routines. Even targets with no RTOS at all are supported with Embedded UML RXF. 

KEY CAPABILITIES

Embedded UML RXF Features

Embedded UML RXF provides you with a library and runtime environment facilitating use of all UML elements even when working with C or C++.

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Connect UML model and requirements

Establish traceability across tool boundaries: Link UML models to requirements held in an external requirements management tool. Click on a link in your UML environment and the up-to-date version of the connected requirement will be displayed. After generating code from your UML model, the text of the requirement will be included in the source code as a comment.

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Automatically include RTOS functions

Usually, a UML model also includes elements defining certain runtime environment settings, such as Active Class. Thanks to the function library delivered with Embedded UML RXF, those functions are easily and automatically included with a click and converted into the correct source code.

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Debug UML models on your target system

Inspect the runtime behavior under real conditions on the target system while you are still elaborating your UML model. With Embedded UML RXF, you execute the model in real time on the target system. You intervene through trigger events, calls, induced errors and check your model using animated sequence and timing diagrams.

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Modeling for target systems of any size, including very small systems

Benefit from the advantages of UML modeling even for small target systems with limited resources, such as an intelligent "keyless go" car key. Embedded UML RXF comes with a highly optimized RTOS providing you with the basic runtime environment functions. Those are included with a click during code generation, and the result is an executable file running completely independently.

BENEFITS

Why engineering teams choose Embedded UML RXF

From accelerating time-to-market to improving code quality, here is what teams consistently gain when they adopt Embedded UML RXF.

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Easy-to-understand, graphical, and non-ambiguous description 

That's what you get with UML modeling for your embedded software project. Your UML description of the application is designed AND documentation at the same time, with guaranteed coherence throughout the project. The risk of misunderstandings or implementation gaps is minimized. Errors are detected early when fixing is less expensive.

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Kick-start your projects

Embedded UML RXF provides you with everything you need to be productive from day 1. Thanks to ready-to-use RXF adapters for a broad range of RTOS and microcontrollers, time-consuming adaptations to your environment are usually not required. The diversity of adapters goes way beyond the targets supported by IBM Rhapsody, adding significant value to your investment.

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Easily port your application to other targets

With Embedded UML RXF you keep your UML model clean from target-specific constructs. RTOS calls will be automatically included depending on the selected target system, and the C/C++ libraries delivered with Embedded UML RXF will take care of generating source code from UML elements that have no equivalent in C/C++. Simply take your application to another system, select the target and you're done.

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Discover errors early through simulation and debugging at the UML model level

Monitor and verify the behavior of your UML model early to check if it meets the specified requirements. Simulate execution within the modeling tool environment to evaluate functions, dependencies, interfaces, etc. Debug your model on the target system to find errors in real-time behavior. Detect and eliminate errors as soon as possible, when bug fixing is less expensive.

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Full transparency from requirements to source code to test

Link the elements of your UML model to the associated requirements. When generating source code, the text of the requirement is inserted as a comment at the appropriate place. The result is full transparency from requirements through to source code.  Add IBM TestConductor to Embedded UML Studio and traceability is extended further to test results.

RESOURCES

Learn more about Embedded UML RXF

Technical documentation, related products, and training to help you evaluate and deploy RXF in your environment.

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DATASHEET

Full feature overview, use cases, and product specifications. Useful for technical evaluation and internal stakeholder review.

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SUPPORT

Reach out to our support team for bugs, new features, or technical support requests by email to: support@sodiuswillert.com.

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FAQ

Common questions about Embedded UML RXF

Technical and commercial questions from engineers and teams evaluating RXF for embedded development.

What is Embedded UML RXF and how does it fit into the Rhapsody environment?

Embedded UML RXF (Realtime eXecution Framework) is a library and runtime environment that operates as the interface between IBM Rhapsody and the target platform. It provides C/C++ implementations for UML constructs (e.g. Active Classes, hierarchical state machines, synchronous and asynchronous messaging, timers, event queues) that have no direct language equivalent. RTOS-specific calls are handled by target adapters activated via compiler parameter. RXF integrates directly into the Rhapsody code generation pipeline; no additional toolchain configuration is required.

What are the technical prerequisites for using Embedded UML RXF?

RXF requires either IBM Rhapsody Developer or Embedded UML Studio (which bundles Rhapsody and RXF together) and a supported C or C++ compiler for your target system. Working knowledge of C or C++ is recommended. UML experience is useful but not required.

How does Embedded UML RXF differ from Embedded UML RXF-Cert?

Embedded UML RXF is the standard framework for UML code generation in embedded systems development.

Embedded UML RXF-Cert is a certified variant designed for projects that require formal compliance with safety standards such as IEC 61508 (up to SIL3), ISO 26262, DO-178B, and DoDAF. RXF-Cert ships with the full certification documentation package: Software Safety Plan, Safety Manual, Verification Plan and Report, Requirement Traceability Table, Architectural Model, and Final Delivery Report. It has a proven track record in certified projects across railway, automotive, and aerospace.

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