Disclaimer

This Disclaimer explains what frescor.org is and what it is not, how you should use the information and tools we publish, and the limits of our responsibility. It applies to all content on the Site, including articles, the glossary, the schedulability calculator and the preserved FRESCOR project archive. Please read it together with our Terms and Conditions.

Last updated: October 19, 2026

1. Independence and non-affiliation

frescor.org is operated by FRESCOR.org as an independent knowledge resource about real-time embedded systems, contract-based and flexible scheduling, timing analysis, real-time operating systems and embedded architectures.

The name FRESCOR refers to the historical research project “Framework for Real-time Embedded Systems based on COntRacts”, which ran from 2006 to 2009 under the European Union’s Sixth Framework Programme (FP6/2005/IST/5-034026). That project was coordinated by Universidad de Cantabria and carried out with a consortium of academic and industrial partners, which are listed on our Partners page for historical reference.

Mentioning a former partner, researcher or institution on this Site does not mean that they have reviewed, approved or contributed to our current content. Opinions expressed in our articles are those of the Site’s authors and editors only.

2. Educational and general information only

The articles, guides, worked examples, glossary entries, FAQs and other material on this Site are published for educational and general informational purposes. They are intended to help engineers, students and researchers understand concepts such as response-time analysis, WCET analysis, scheduling algorithms and RTOS selection.

The content is necessarily general. It cannot account for the specific hardware, software, workload, toolchain, operating environment, contractual requirements or regulatory context of your project. You should not rely on it as the only basis for any technical, commercial or legal decision.

3. No engineering or safety-certification advice

Nothing on this Site constitutes professional engineering advice, safety assessment, or certification guidance for any particular system. Developing software and systems for safety-critical or high-integrity domains, such as aerospace, automotive, rail, medical devices, industrial control or nuclear, is governed by demanding standards and regulatory regimes, including for example:

• DO-178C (airborne software) and DO-254 (airborne electronic hardware);
• ISO 26262 (road vehicles functional safety);
• IEC 61508 (functional safety of electrical, electronic and programmable electronic systems) and its sector derivatives;
• EN 50128 / EN 50716 (railway software);
• IEC 62304 (medical device software).

Compliance with these standards requires qualified and experienced professionals, appropriate processes, qualified tools, independent assessment and, in many cases, approval by a certification authority or notified body. Our articles may describe techniques used in such contexts, but reading them does not make a system compliant, and we do not claim that following our content will satisfy any standard or regulator.

If you are working on a system whose failure could cause injury, death, environmental damage or significant financial loss, always consult appropriately qualified engineers and safety professionals and follow the requirements of the applicable standards.

4. Accuracy and currency of information

We take care to make our content technically accurate and to cite reliable sources. Our process is described in our Editorial Policy. However, real-time systems is an active field: operating system releases, kernel interfaces, tool versions, hardware platforms and standards change over time. Information that was correct when published may become outdated.

We therefore make no representation or warranty that the content is complete, accurate, current or free of errors. Code snippets, configuration examples and command lines are illustrative. Always check the official documentation for the version you are using and test any change in a safe environment before applying it to a production or deployed system.

5. Calculators and interactive tools

Our schedulability calculator performs utilization-based tests for Rate Monotonic and Earliest Deadline First scheduling and classic response-time analysis, and draws an illustrative Gantt chart. It is an educational tool, designed to help you explore how scheduling theory works.

Its results depend entirely on the parameters you enter and on the simplifying assumptions of the underlying models, such as independent periodic or sporadic tasks, known worst-case execution times, a single processor, and limited or no accounting for blocking, release jitter, interrupts, cache effects, scheduler overheads and multicore interference. Real systems frequently violate these assumptions.

The calculator’s output is not a substitute for formal verification, validated timing analysis tools, measurement on target hardware, or review by a qualified engineer. Do not use it as evidence of schedulability in a safety case or certification submission.

6. External links

We link to external websites, such as official documentation, standards bodies, research papers and open-source projects, because we believe they are useful. We do not control these sites and are not responsible for their content, accuracy, availability, security or privacy practices. A link does not imply that we endorse the site, its owner or its products. External content may change after we link to it; if you find a broken or inappropriate link, please let us know.

7. Trademarks

Product names, operating systems, tools, logos and company names mentioned on this Site are used for identification and descriptive purposes only. They may be trademarks or registered trademarks of their respective owners. For example:

• Linux® is the registered trademark of Linus Torvalds in the U.S. and other countries.
• Zephyr™ and the Zephyr Project are trademarks of The Linux Foundation.
• FreeRTOS™ is a trademark of Amazon Web Services, Inc. or its affiliates.
• Raspberry Pi is a trademark of Raspberry Pi Ltd.
• Simulink® and MATLAB® are registered trademarks of The MathWorks, Inc.
• Arm® and Cortex® are registered trademarks of Arm Limited (or its subsidiaries).

All other trademarks belong to their respective owners. Their use on this Site does not imply any affiliation with, sponsorship by or endorsement from those owners, and their omission from the list above does not mean that we claim any rights in them.

8. Affiliate links and sponsorship

At present, this Site does not use affiliate links and does not publish sponsored content. We do not receive payment from vendors for mentioning, comparing or recommending products, operating systems or tools. If this changes in the future, affiliate links and sponsored content will be clearly labeled, and this Disclaimer will be updated.

We do offer our own professional services and digital products, listed on our services page. Where an article mentions one of our own offerings, that relationship is clear from the context.

9. Errors and corrections

We welcome reports of errors, outdated information or unclear explanations. If you spot a mistake, please contact us at support@frescor.org or through our contact page, ideally with the page URL and a reference to a reliable source. We review reports and, where a correction is needed, update the content and note significant corrections as described in our Editorial Policy.

10. Archive material provided “as is”

Sections of the Site such as the Project Overview, Objectives, Expected Results and Links and Documents preserve or summarize material from the historical FRESCOR project. This material is provided “as is”, for historical and educational interest. It reflects the state of the project and the field at the time it was written (2006–2009) and has not been updated to reflect later research, technology or standards.

Archive material belongs to its original authors and rights holders. Statements about the project’s goals or expected results describe intentions at the time and should not be read as claims about the current Site or as current performance figures. Contact details, URLs and organizational names in archive material may no longer be valid. If you are a rights holder and have a concern about archive material, please see our DMCA & Copyright Policy.

11. Limitation of liability

To the fullest extent permitted by law, FRESCOR.org is not liable for any loss or damage, whether direct, indirect, incidental or consequential, arising from your use of or reliance on the free content, tools or archive material on this Site, including any errors or omissions in it. This includes, without limitation, loss of data, loss of profits, project delays, system failures or costs of redesign.

Nothing in this Disclaimer limits or excludes any liability that cannot be limited or excluded under applicable law, including liability for death or personal injury caused by negligence, or for fraud. Paid services and digital products are subject to the specific terms in our Terms and Conditions and to any mandatory consumer rights you have.

12. Contact

If you have questions about this Disclaimer, please contact FRESCOR.org:

• E-mail: support@frescor.org
• Postal address: available on request via support@frescor.org