BORGES, R.W.-Real-time Operating System Aplicability for small and low cost embedded systems-July/2008; Embedded Systems, more and more are gaining importance, due to the increase of features requested on equipments, the regulatory standards and the costumers and market requirements. This increment on requirements increases the software size and complexity, which importance significantly grows. Realtime Operating Systems represents a powerful tool to manage the complexity, help the software reuse and improve portability of the software and also reduce the time-tomarket. This work aims to analyze the real-time operating systems, verifying their application on low cost embedded systems using small microcontrollers (8 and 16-bit), evaluating their characteristics and propose the best architectures for software development. To attend this proposal, it was performed a survey of Brazilian embedded system development, evaluates the low cost embedded system characteristics, discusses the viability of RTOS usage and performs a comparative study of embedded software architectures. Results show that simplified architectures like the Superloop presents vantages over the operating systems due to their low memory and processing consumption. The operating system, besides helping on time management and code modularity, is difficult to implement in small microcontrollers, due to the high memory and processing consumption. The operating systems are more applicable to small embedded systems with at minimum 4 Kbytes of RAM memory and process with maximum execution time (deadlines) over 1 ms, conditions that do not causes microcontroller overload. In This work is also presented an overview of Brazilian embedded system development.

No abstract