A real time operating system for embedded platforms

Abstract

SDL (Specification and Description Language) is today widely used for description and development of complex systems. One of the major benefits of SDL is the possibility to graphically describe a complex system, as well as the capability to analyze the system before implementation. This thesis evaluates SDL as a formal description language for use in an embedded platform. To be able to map the properties and behaviour of an SDL system into a programming language, a Real Time Operating System (RTOS) must be used. We will evaluate all properties of SDL to get a overview of which properties can be mapped to a programming language, which properties can be omitted, and which properties isn’t possible to map to a programming language. Further, well evaluate what properties of an RTOS are essentially for the implementation of an SDL system. Several RTOS already exists on the market today. Some are specifically developed with mapping between SDL and ANSI C as the main task. Our target is the Atmel AVR 8 bit microcontroller. A microcontroller built on the Harvard architecture (separate memories and buses for program and data). Through this master thesis we have discovered the shortcomings of several RTOS. Due to this, we have developed our own RTOS, SDL REFLEX, specifically designed to our needs and with the AVR microcontroller as target.