Examples of real-time operating systems. Examples of network operating systems
Real-time operating system (RTOS) -This OS, which guarantees a certain ability for a given time interval. For example, it can be designed to show that an object has become available to the robot on the assembly line. Such shells are classified as "hard" and "soft".
Rigid operating systems in real modetime, it is assumed that the calculation can not be performed if the object is not available at the appointed time (such an operation will fail).
In a soft operating system in real modetime, the assembly line under such conditions will continue to function, but the production volume may be lower, since the objects are not able to be available at the appointed time, as a result of which the robot will be temporarily unproductive.
Before you give examples of operating systemsreal time, you need to understand the features of their use. Some such OSs are created for a special application, others for a more general one. In addition, some general-purpose shells are also sometimes used to operate in real-time mode. As examples of operating systems of this type can come out well-known Windows 2000 or IBM Microsoft / 390. That is, even if the OS does not meet certain requirements, it may have characteristics that allow it to be viewed as a solution for a specific application task in real time.
Examples of operating systems and their characteristics
In general, real-time operating systems have the following characteristics:
- Technological flows that can be a priority.
- A sufficient number of interrupt levels.
Real-time operating systems are often used insmall embedded shells that are used in the format of micro devices. So, some kernels can be considered as single-tasking operating systems (examples: kernels in the composition of iOS, Android, etc.) in real time. However, other components of the device, such as drivers, are required to perform their tasks. That's why a full-fledged real-time operating system, as a rule, happens more than just a kernel.
A typical example of an RTOS application isHDTV receiver and display. It must read the digital signal, decode it and display it as incoming data. Any delay will be noticeable as pixel video and / or distorted sound.
However, when the request "give examples of operating systems of this type" sounds, the most well-known names are mentioned. What is included in this group?
VxWorks from WindRiver
VxWorks is the operating system of the realtime, developed as proprietary software with the help of WindRiver. Originally released in 1987, VxWorks was originally intended for use in embedded systems that require real-time and deterministic performance. For example, operating systems of this type find application in the areas of security and safety, various industries (especially aerospace and defense), the production of medical devices, industrial equipment, robotics, energy, transport management, network infrastructure, and the improvement of automotive and consumer electronics.
VxWorks supports Intel (x86, including newversion of IntelQuarkSoC and x86-64), MIPS, PowerPC, SH-4 and ARM-architecture. This RTOS comes with a powerful kernel, middleware, support for additional paid packages and third-party hardware technologies. In its latest release - VxWorks 7 - the system was upgraded for modularity and upgrade so that the OS kernel is kept separate from middleware, applications and other packages.
Also classic examples of operating systemsThe specified type is some Unix-like shell. This is QNX Neutrino, originally developed in the early 1980s by the Canadian company Quantum Software Systems. Ultimately, the development was purchased by BlackBerry in 2010. QNX is one of the first commercially successful microkernel operating systems that is used in various devices, including auto- and mobile phones.
FreeRTOS is a popular nuclear OS in modeReal time for embedded devices, which is loaded by 35 microcontrollers. It is distributed under the GPL with an additional restriction and optional exceptions. The restriction prohibits benchmarking, while the exception allows you to use your own user code along with the closed source code, while keeping the kernel itself. This makes it easier to use FreeRTOS in your own applications.
Windows Embedded Compact is an operating systema subfamily system developed by Microsoft within the Windows Embedded family of products. Unlike Windows Embedded Standard, which is based on Windows NT, these operating system examples use an exclusive hybrid core. Microsoft provides Windows CE licenses to original equipment manufacturers who can modify and create their own user interfaces, providing a technical basis for this.