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SYMO - Real-Time Kernel - Ex -jobs presentation


Larisa Rizvanovic , Larisa Rizvanovic



Start time:

2001-04-27 09:00

End time:

2001-04-27 09:30



Contact person:


AbstractEmbedded systems are a fast growing and exciting market. Embedded systems control everything from the blinking lights in athletic shoes to flight control systems for high performance military aircraft. A complex embedded system may utilise an operating system to support the execution of its application program. When an operating system is used, it is most likely a real-time operating system (RTOS). A RTOS is an operating system designed and optimised to handle the strict timing constraints associated with events in real-time applications. The aim of this paper is to describe functionality, design and configuration of one minimal real time unit, called Symo. Symo is a trimmed version of a real time unit RTU that is a result of one research project at Mälardalen University in Västerås, Sweden. Symo is a small system, but despite its size, it provides support for many services that you can find in any commercial OS. Priority scheduling algorithm, semaphores, delay and exception handling are some of these. Symo can handle one CPU and a generic number of tasks, priority levels and four external interrupts. There are two version of Symo, one made in hardware, HW Symo, and the other one implemented in software, called SW Symo. SW Symo is a result of the first part of my Master Thesis. The assignment was to develop a real time operating system with the similar interface as HW Symo, in order to benchmark both operating systems and compare the results. At the time this work started, HW Symo was already a manufactured product.

Larisa Rizvanovic,