Embedded systems are found in all market segments:
consumer commercials, PC peripherals, telecommunications, automotive
and in the fields of aerospace and nuclear research. It is a very
demanding technology where products must meet special requirements such
as cost effectiveness, low power, small footprint and a high level of
system integration. The embedded systems mostly work in a real time
environment where deadlines should not be missed at any instance. The
platform to execute this real time application software is known as a
Real Time Operating System (RTOS). RTOS consists of a priority based,
preemptive, multitasking scheduler to manage the interrupts. Here the
requirements of an OS to be a RTOS are discussed and the facilities
available for a widely used RTOS VxWorks are also overlooked. Thus we
can say that the basic requirements of an OS to be a RTOS are its fast
intertask synchronization and communication capabilities, priority
based preemptive interrupt handling capability etc. Also comparing to a
general OS RTOS only requires a small footprint. It is a modular OS. .