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Abstract
Atualmente, a utilização dos sistemas operacionais, principalmente os sistemas de tempo real (RTOS), tem sido de grande importância no desenvolvimento de sistemas embarcados. Cada vez mais, diferentes e variadas funcionalidades são requisitos dos projetos de sistemas embarcados, como interfaces de comunicação com e sem fio, interfaces com o usuário através de displays, interfaces de acesso de dado como USB, serial, etc. Com o aumento da complexidade, fica extremamente difícil construir um sistema que seja estável e que atenda aos requisitos de tempo a partir de estruturas de programas comuns como o Super Loop. A fim de demonstrar os problemas inerentes deste tipo de arquitetura, foi desenvolvida uma aplicação utilizando o Super Loop e a mesma foi portada para uma solução baseada em RTOS demonstrando os principais conceitos que envolvem um sistema operacional, como utilizá-lo, e os benefícios obtidos com a sua utilização, como estabilidade do sistema, sincronização entre tarefas e cumprimento dos requisitos de tempo.
Palavras-chave: Sistemas operacionais de tempo real. Sistemas embarcados. Escalonamento.
Porting an embedded system application with super loop architecture to operate with real-time operating system
Currently, the use of operating systems, especially real-time systems (RTOS), has been of great importance in the development of embedded systems. Increasingly, different and varied features are requirements for embedded system projects, as wired and wireless communication interfaces; user interfaces through displays; data access interfaces such as USB, serial, etc. With the increase in complexity, it becomes extremely difficult to build a system that is stable and that meets the time requirements from common program structures like Super Loop. In order to demonstrate the inherent problems of this type of architecture, an application was developed using Super Loop and it was ported to a solution based on RTOS, demonstrating the key concepts involving an operating system, how to use it and the benefits gained from its use as system stability, synchronization between tasks and fulfillment of time requirements.
Keywords: Real-time operating systems. Embedded systems. Scheduler.
References
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