SACI_FTR_LOADER: A Dynamic Loader for the On-Board Computer of the First Brazilian Microssatelite

Abstract This paper describes the conception and implementation of a dynamic loader, called SACI_FTR_LOADER, which will be used to upload programs from a ground station onto the onboard computer (called Trisputer) of the first Brazilian microssatelite. The satellite, named SACI (Satellite for Scientific Applications), will be launched by the middle of the next year. The loader is part of the real-time operating system designed to control the resources of the machine, which also incorporates software fault tolerance techniques. The Trisputer is a fault-tolerant multiprocessor computer system which was designed having in mind the high reliability requirements associated with the mission. This goal was achieved by introducing fault tolerance at both hardware and software levels. The on-board computer consists of three processing modules, each one based on a Transputer T-805-30 INMOS microprocessor