Real-time Software Architecture for Consumer Appliances

This technical report describes the design of a platform-independent firmware architecture for distributed, real-time control systems with a flexible user interface and high-level control algorithm programming capabilities. The framework consists of a control card, multiple local I/O cards and a bridge card connected to the same real-time bus. The I/O cards provide digital and analog inputs and outputs, whereas the bridge card offers the capability to communicate with remote user interface hosted on other networks. The control card hosts both the control software module which handles local inputs and outputs, as well as software that serves both local and remote user interface requests. The proposed software architecture also provides support for the use of symbolic names in the high-level control algorithm as well as various sorts of user interfaces. The report is divided into five chapters: Chapter 1 outlines the general network structure; Chapter 2 focuses on the cyclic execution model which is used to accommodate the real-time control; Chapter 3 deals with the process image which is designed bearing symbolic names in mind; Chapter 4 explains how to manage both local and remote user interfaces in a uniform way, and how to map them onto the cycle execution; whereas Chapter 5 provides details about the software architecture and demonstrates a couple of use cases.