UML based design of time triggered systems

This paper presents how the platform-specific development environment of time-triggered (TT) systems can be integrated with a visual design toolkit based on UML. The built-in facilities of UML and the modeling extensions introduced by us enable the unification of the advantages provided by both the embedded development environment and the UML tools. UML offers visual design, automatic code and documentation generation, while the underlying TT development environment offers platform-specific task and communication scheduling and fault tolerance middleware construction. This results in an integrated system that is capable of supporting the entire development within the framework of the UML tool

1. Introduction

Embedded systems are typically applied for performing tasks closely related to the hardware, i.e. they can not expect a programmer-friendly multi-layered virtual machine interface and operating system API. This direct connection to the hardware impacts the fundamental implementation aspects (e.g. the interface design), as well as the dependability and timing considerations [3]. Fault tolerance measures can involve redundant communication channels, modular hardware redundancy, software diversity, etc. As a special aspect, real-time operation can be required from the embedded system. In these cases sophisticated task and communication scheduling and special algorithm design are needed [5].