Abstract
The CLEARSY Safety Platform (CSSP) is both a hardware and software platform aimed at developing safety critical applications. A smart combination of hardware features (double processor) and formal method (B method and code generators) was used to produce a SIL4-ready platform where safety principles are built-in. A first version, SK0, was released for education purpose with a restricted application template. An industry-strength version, CS0, was then released, providing more degrees of freedom at the cost of a more tricky development and engineering process. This article presents the new CS0 modelling paradigm, lists the conditions to be verified by the system developed, and briefly introduces a first application, software only: a safety flasher.
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Notes
- 1.
The software model is proved to be defect-free - complying with its formal specification and without programming errors. The code generators and the compilers are not defect-free. They are not required to be defect-free as the defects are detected with divergent behaviour during execution.
- 2.
- 3.
The safety case contains all the details leading to complete demonstration (SIL4) but is not disclosed here (the safety case is around 120 pages). The CSSP has already been certified 3 times.
- 4.
The top-level sequencer is hard-coded and cannot be modified.
- 5.
In B, a BASIC machine is a component with a formal specification (a B machine) but with a handwritten implementation. A BASIC machine allows to integrate third party software in a B project.
- 6.
I/O requirements are so diverse among the safety systems we have been involved into that we have decided to separate I/O from the safety computer.
- 7.
They are not detailed here, but may be found in the CSSP \(CS_0\) User Manual.
- 8.
The complete safety flasher model and code are going to be available on [3].
- 9.
The situation is different from the SK\(_0\) where these function calls were included once for all in the top-level sequencer, not modifiable by the developer.
- 10.
References
Abrial, J.: The B-Book - Assigning Programs to Meanings. Cambridge University Press, Cambridge (2005)
Abrial, J.: Modeling in Event-B - System and Software Engineering. Cambridge University Press, Cambridge (2010)
CLEARSY: the clearsy safety platform programming handbook (2020). https://github.com/CLEARSY/CSSP-Programming-Handbook. Accessed 29 May 2020
CLEARSY: Github clearsy (2020). https://github.com/CLEARSY/. Accessed 29 May 2020
Lecomte, T.: Double cœur et preuve formelle pour automatismes sil4. 8E-Modèles formels/preuves formelles-sûreté du logiciel (2016)
Lecomte, T.: The bourgeois gentleman, engineering and formal methods. In: Symposium, AFFORD 2019, Porto, Portugal, 7–11 October 2019. Proceedings (2019)
Lecomte, T., et al.: Low cost high integrity platform. In: Symposium, ERTS 2020, Toulouse, France, 29–31 January 2020. Proceedings (2020)
Wikipedia contributors: cyclic redundancy check – Wikipedia, the free encyclopedia (2020). https://en.wikipedia.org/wiki/Cyclic_redundancy_check
Wikipedia contributors: Intel hex – Wikipedia, the free encyclopedia (2020). https://en.wikipedia.org/wiki/Intel_HEX. Accessed 08 May 2020
Wikipedia contributors: programmable logic controller – Wikipedia, the free encyclopedia (2020). https://en.wikipedia.org/wiki/Programmable_logic_controller. Accessed 08 May 2020
Wikipedia contributors: safety integrity level – Wikipedia, the free encyclopedia (2020). https://en.wikipedia.org/wiki/Safety_integrity_level. Accessed 08 May 2020
Acknowledgements
The work and results described in this article were partly funded by:
– BPI-France (Banque Publique d’Investissement) and Métropole Aix-Marseille as part of the project LCHIP (Low Cost High Integrity Platform) selected for the call AAP-21.
– ADEME (Agence de l’Environnement et de la Maitrise de l’Energie) selected for the programme “Vehicle of the Future” of Investissements d’Avenir.
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Lecomte, T., Lavaud, B., Sabatier, D., Burdy, L. (2020). A Safety Flasher Developed with the CLEARSY Safety Platform. In: ter Beek, M.H., Ničković, D. (eds) Formal Methods for Industrial Critical Systems. FMICS 2020. Lecture Notes in Computer Science(), vol 12327. Springer, Cham. https://doi.org/10.1007/978-3-030-58298-2_9
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