LEON
32-bit CPU microprocessor core originally designed by the European Space Agency
LEON (from Spanish: león meaning lion) is a radiation-tolerant 32-bit central processing unit (CPU) microprocessor core that implements the SPARC V8 instruction set architecture (ISA) developed by Sun Microsystems. It was originally designed by the European Space Research and Technology Centre (ESTEC), part of the European Space Agency (ESA), without any involvement by Sun. Later versions have been designed by Gaisler Research, under a variety of owners. It is described in synthesizable VHSIC Hardware Description Language (VHDL). LEON has a dual license model: A GNU Lesser General Public License (LGPL) and GNU General Public License (GPL) free and open-source software (FOSS) license that can be used without licensing fee, or a proprietary license that can be purchased for integration in a proprietary product.
The core is configurable through VHDL generics, and is used in system on a chip (SOC) designs both in research and commercial settings.
History
The LEON project was begun by the European Space Agency (ESA) in late 1997 to study and develop a high-performance processor to be used in European space projects.
The objectives for the project were to provide an open, portable and non-proprietary processor design, capable to meet future requirements for performance, software compatibility and low system cost. Another objective was to be able to manufacture in a single-event upset (SEU) tolerant sensitive semiconductor process. To maintain correct operation in the presence of SEUs, extensive error detection and error handling functions were needed.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Mar 13, 2026. The linked authority identifier is Q1798019. None of the 1 selected statements returned an explicit reference. The first chronological checks are 1997.
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This entry incorporates text from “LEON” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.