What are the real time operating system?Pay attention to the detailed study of the RTOS.First of all, it is a special kind of operating system, which differ from the generic operating system for its performance and speed in the worst situations.There are many concepts that reveal specifics:
- RTOS - a system that is able to provide the necessary services for a certain period of time;
- real-time system, which is characterized by constant readiness, and the processing of information transparent to the user;
- "fast system," which comes to the fore not the response time RTOS, and enough time to work with the application.
For completeness, it is worth paying attention to the characteristics of real time operating systems.The most important feature is guaranteed and stable reaction to events.The tasks of any level (high and low priority) must not conflict with each other and displace each other.High level requirements at the time of response to a specific event in real time.
Types of real time operating system
separating them depending on the program: rigid (hard), soft (soft) and interactive.Briefly look at each type.
Hard RTOS have a fixed time response to events in real time.Example hardware interrupt, display control commands to be processed within a certain time, which occurs in 100% of cases.
soft real-time systems allow 80-90% of the cases to deviate from the defined timeframe one order.But most importantly, these delays did not lead to irreparable consequences.
Interactive RTOS include the human factor (when the individual awaits a response from the system after they set guidelines or instructions).
most popular real-time operating systems and their characteristics
Most RTOS - gated and difficult for them to obtain detailed information.The company has developed WindRiver Systems VxWorks (hard RTOS) for embedded software development on PC.It is based on the work of the host computer on which the software is being developed, and the client computer, where it is used for management of VxWorks.
These real-time operating systems - shirokonastraivaemye, but program modules can not be used in a different environment, which makes them quite limited in use.Benefits include:
- Unlimited number of tasks.
- Number of priorities - to 256.
- Tasks are scheduled cyclically or by priority.
- semaphores, which help manage critical system resources.
real time operating system QNX Neutrino Realtime Operating System - the brainchild of the company QNX Software Systems.It is based on cross-server architecture and is characterized by a great multitasking with priority mode.Each element of the system works independently: failures and malfunctions, any unit can be restarted independently without affecting the work of the core or other components.It also has a deep configuration bind to the basic nucleus, which eliminates the work in another environment.
ChorusOS is an example of an embedded operating system, which is widely used in telecommunications.It supports a variety of telecommunication protocols, Java-technology, which allows the introduction of new developments and applications.
difference from running public and destination
RTOS differ from general-purpose deterministic nature of the work, which is due to the strict control of the time spent on processing tasks.The concept of "determinacy" describes a predefined time interval over which runs a real-time program.
