Cobham Gaisler AB provides IP cores and supporting development tools for embedded processors based on the SPARC architecture. We specialize in digital hardware design for both commercial and aerospace applications

LEON processor in focus at DASIA 2007 conference in Naples, Italy

The international space system engineering conference DASIA 2007 (DAta Systems In Aerospace) was held this year in May - June in Naples, Italy. The LEON processor and related tools were discussed in several oral presentations during the conference.

A full session was dedicated to LEON based processors, during which Gaisler Research presented a wide range of applications in which the LEON processor is being used, covering LEON2-FT in the AT697F device from Atmel, LEON3-FT being implemented on various technologies, and finally the status of the LEON4 study.

 - "This conference again confirms Gaisler Research's position as the leading supplier of high performance processor IP solutions to the space industry", says Jiri Gaisler the CTO of Gaisler Research AB.

Special LEON session

Gaisler Research, Sweden, presented the status of several LEON based developments, covering the LEON2-FT, LEON3-FT and LEON4 processors.

The latest updates to the LEON2-FT model that Gaisler Research has implemented, and that will be included in the AT697F devices from Atmel, were presented. The updates cover additional functionality such as enhanced write protection, wider timers, additional external interrupts and an improved EDAC addressing scheme.

The LEON3-FT processor has so far been manufactured and validated on a 0.25 um technology, demonstrating its Single Event Upset (SEU) detection and correction capabilities, and on a 0.18 um technology, demonstrating the over-all system-on-a-chip capability of the design.

The LEON3-FT processor will further be manufactured in two deep sub-micron technologies. In the first of two ESA developments, the processor will be manufactured on the UMC process using the DARE library developed by IMEC, Belgium. The Design Against Radiation Effects (DARE) library uses the standard 0.18 um UMC ASIC flow and provides protection of logic and registers. In the second planned activity a LEON3-FT multi-processor (MP) system will be manufactured on a 90 nm ASIC technology to demonstrate the MP functionality of the processor.

The LEON4 processor is under development and is funded by the Swedish National Space Board (SNSB). The objective is to improve the processor throughput with 50%. Extending the cache interface to 64 bits and adding a cache streaming FIFO, implementing a non-blocking pipeline that is extended in number of stages, and improving the GRFPU will achieve this.

Gaisler Research presented an AT697F companion chip (GR701A) that interfaces the LEON2-FT processor via the PCI interface. The GR701A companion chip provides three SpaceWire links, Mil-Std-1553 Bus Controller, Remote Terminal and Bus Monitor functionality, a redundant CAN-2.0 bus interface, on-chip memory, UARTs, timers, etc. The device is implemented in an Actel RTAX2000S CQFP352 part. The companion chip can also be used with any other processor featuring a PCI interface.

Gaisler Research also presented their software tools and operating systems support. This covered the industry standard instruction simulator TSIM and its recent improvements (e.g. memory EDAC emulation, SDRAM support, MMU emulation), and the upcoming hardware accelerated simulator TSIM-HW that will be able to simulate the AT697F device at real-time or better performance. In addition to the free RTEMS, LINUX and ECOS operating systems, Gaisler Research now also supports the commercial products VxWorks 5.4, 6.3, 6.4 and ThreadX.

EADS ASTRIUM, France, presented the Spacecraft Controller On-a Chip (SCOC) ASIC development that is based on the LEON3-FT processor with the GRFPU-FT floating- point unit, both from Gaisler Research. The SCOC ASIC is intended for spacecraft on-board data handling systems, in which it can replace several subsystems currently implemented as separate boards or units. The SCOC covers functionalities such as processor, telemetry and telecommand, Mil-Std-1553 and CAN buses, and SpaceWire networks.

ASTRIUM ST, Germany, presented their Space Infrastructure Computer (SPAICE) that is based on the AT697F device from Atmel, France. The AT697F device has been designed using on the fault-tolerant LEON2-FT VHDL model that has been developed in co-operation between the European Space Agency (ESA) and Gaisler Research.

Other presentations

Acer, Taiwan, and Carlo Gavazzi Space, Italy, presented the Command and Data Management Unit (CDMU) of the ARGO satellite that is being developed for the Taiwanese National Space Organization (NSPO). The board computer of the CDMU is based on the LEON3-FT-RTAX processor from Gaisler Research. The processor is implemented in an Actel RTAX2000S part and operates at system frequencies up to 25 MHz. It provides standard peripherals such as timers and UARTs, EDAC protected memory, and two high-speed SpaceWire links.

German Aerospace Center (DLR), Germany, presented the development of the BepiColombo Laser Altimeter, BELA. The BELA digital processor module uses a LEON3-FT processor with SpaceWire interfaces, all provided by Gaisler Research.

Alcatel Alenia Space, Italy, presented the ExoMars descent module avionics architecture study. Several SPARC based processor systems were evaluated in the study and the current baseline is the OMNIA ASIC. The OMNIA ASIC is a system-on-a-chip design based on LEON2-FT processor that has been enhanced with the GRFPU-FT High-Performance Floating-Point Unit developed by Gaisler Research.

Verhaert Space, Belgium, presented their Advanced Data and Power Management System (ADPMS) that is based on the AT697E LEON2-FT processor. ADPMS is planned for in-orbit demonstration next year on ESA's PROBA-II technology demonstration satellite mission. In addition to performing the initial system studies and trade-offs, Gaisler Research has developed the telemetry and telecommand Actel RTAX2000S FPGA used in ADPMS.

MDA Space Missions, Canada, presented the Phoenix Meteorological Instrument data processing hardware and software architecture. The instrument features two computers, both based on the LEON2 processor.

Rapita Systems, UK, presented an analysis of LEON cache effects on the timing analysis of on-board applications. The objectives have been to evaluate the cache-sensitivity of typical on-board applications and to consider how applications should use the cache to improve predictability and analysability. New worst-case execution time analysers have been evaluated.

European Space Agency (ESA), The Netherlands, presented the Virtual Spacecraft Reference Facility in which one of the main building blocks, the Software Validation Facility (SVF), is based on the TSIM instruction simulator from Gaisler Research.

About Gaisler Research AB

Gaisler Research AB is a provider of SoC solutions for exceptionally competitive markets such as aerospace, military and demanding commercial applications. The Gaisler Research's products consist of user-customizable 32-bit SPARC V8 processor cores, peripheral IP-cores and associated software and development tools. Gaisler Research solutions help companies develop highly competitive application and customer-specific SoC solutions.


The conference is organised by EUROSPACE, an association of the European space industry, in co-operation with the European Space Agency (ESA), among others.

DASIA 2007 (DAta Systems In Aerospace) - Programme, SP-638 Abstracts