Embedded Operating System
An embedded operating system is a computer operating system designed for use in embedded computer systems. These operating systems are designed to be small, resource-efficient, dependable, and reduce many features that aren’t required by specialized applications.
The hardware that runs an embedded operating system is usually quite resource-constrained. Embedded hardware systems are typically quite specific, and it means that these systems are designed to cover certain tasks due to limited resources.
In this article, you will learn about the embedded operating system with its types and many other features.
What is Embedded Operating System?
An embedded operating system is a computer operating system designed for use in embedded computer systems. It has limited features. The term “embedded operating system” also refers to a “real-time operating system”. The main goal of designing an embedded operating system is to perform specified tasks for non-computer devices. It allows the executing programming codes that deliver access to devices to complete their jobs.
An embedded operating system is a combination of software and hardware. It produces an easily understandable result by humans in many formats such as images, text, and voice. Embedded operating systems are developed with programming code, which helps convert hardware languages into software languages like C and C++.
The embedded operating system improves overall efficiency by controlling all hardware resources and minimizing response times for specific tasks for which devices were built.
How does an Embedded System work?
People commonly wonder how an embedded system works since there is a high need for complex product technology, which provides opportunities for embedded software developers. In contrast to a desktop PC, which loads or runs applications, an embedded operating system is built for fewer tasks and typically handles a single application on a device.
Due to the limited scope of operating system functions, it must be reliable and run smoothly with its size, processing power, and requirements. That specific application is essential to the end product’s functionality. Wind River VxWorks, Embedded Linux and Android, and QNX are some of the top embedded operating systems for commercial and industrial applications.
History of Embedded Operating System
The Apollo Guidance Computer (AGC) introduced embedded operating systems in the 1960s, while Linux and Android are more new developments to the market. The AGC is a non-profit organization that promotes each Apollo command module (ACM), and Apollo Lunar Module (ALM) had it installed. The AGC offered computation and electronic interfaces for the navigation, guidance, and control of the spacecraft.
Since then, embedded computer systems have gone a long way, and the evolution appears to be far from over, owing to advancements in microcontroller technology from 8-bit to 16-bit, and eventually 32-bit. Since embedded computer systems are growing more complex, operating systems have grown essential to manage embedded software effectively.
Types of Embedded Operating System
There are various types of Embedded operating systems. Some of them are as follows:
Real-Time Operating System
A real-time operating system (RTOS) is a deterministic operating system with limited functionalities that allows multi-threaded applications by giving processed outputs within set time limitations. Since some apps are time-critical, they must be executed exactly when they are expected to maintain the entire system functioning.
The real-time operating system is dependent on clock interruptions. Interrupt Service Routine (ISR) interruptions are generated by this system. The Priority system was implemented by RTOS for the execution of all types of processes. The process and the RTOS are synchronized and can communicate with one another. The RTOS is stored on a ROM (Read Only Memory) chip because this chip can store data for a long time.
Multi-tasking Operating System
The multitasking operating system may execute multiple tasks at the same time. In a multitasking operating system, multiple tasks and processes run at the same time. If the system contains more than one processor, it may perform a wide range of functions.
The multitasking operating system is switched between the multiple tasks. Some tasks are waiting for events to occur, while others are receiving events and preparing to run. When using a multitasking operating system, software development is easier since different software components may be made independent of each other.
Preemptive Operating System
A multitasking operating system that interprets task preemption is known as a preemptive operating system. A task with a higher priority is always defined and executed before a task with a lower priority. Such multitasking operating systems improve system reaction to events and simplify software development, resulting in a more dependable system. The system designer may calculate the time required for service interpreters in the system and the time required by the scheduler to switch tasks. Such systems can fail to meet a system’s deadline, and the program is unaware of the missed deadline. CPU load can be naturally measured in a preemptive operating system by defining a lower priority process that does nothing except increment the counter.
Rate Monotonic Operating System
Some embedded systems are designed to use a specific task scheduling method known as ‘Rate Monotonic Scheduling’. It is an operating system that assures that tasks in a system may operate for a specific amount of time and duration of time. It is a priority-based scheduling algorithm. It is used in operating systems as a preemptive. It means that all tasks can be interrupted or suspended by other tasks within a short period of time. It is generally used to perform shorter tasks with higher priority.
Single System Control Loop
It is a very simple type of operating system designed to perform only one function. It is used in several devices, including smartphones, thermostats or temperature controls, digital controllable equipment, etc. Users may set any point of temperature variable as desired in this type of OS. Several sensors are included in this system to determine various temperature points in the environment.
Characteristics of Embedded Operating System
There are various characteristics of an embedded operating system. Some of them are as follows:
- It provides real-time operations.
- Direct use of interrupts
- Input/Output device flexibility
- Reactive operation
- Streamlined protection mechanisms
- Configurability
Popular Embedded Operating Systems
There are various popular embedded operating systems. Some of them are as follows:
eCos
It stands for ‘Embedded Configurable Operating System’, and all of its components provide a wide range of configuration options. The eCos operating system may support a wide range of popular embedded CPUs.
mbed OS
It is a free and open-source embedded operating system that offers a systematic and comprehensive environment for intelligent hardware development.
VxWorks
Wind River Company firstly introduced it in 1983. It is supported with task synchronization, memory efficiency management, and other features.
µC/OS-II:
It is introduced based on the μC/OS principle. μC/OS-II may handle 64 tasks and provide various functionalities such as interrupt services, task scheduling, memory management, synchronization, and time management.
FreeRTOS
It is a lightweight operating system that supports the priority scheduling algorithm. It provides various functionalities like memory management, message queue, task management, semaphore, time management, etc.
QNX
QNX was created in 1980 and is a commercial embedded real operating system that requires the POSIX specification to compile.
µ Clinux
It stands for ‘Micro-Control Linux’, and it is the latest version of embedded Linux. It is capable of grab all features of the Linux operating system.
Embedded Operating System Uses
The embedded operating system is commonly used in various areas, including car navigation systems, multimedia players, airplane navigation systems, and medical equipment.
Car navigation system
The car navigation system is a small computer system with a touch screen that enables the driver to navigate numerous menus such as audio playback, radio, GPS and route mapping, fuel level, hands-free calls, and tire pressure monitoring systems. All of these tasks are performed by the computer to improve the driving experience.
Parking Metering
Smart city parking meters use the embedded system to manage the user input and track time and costs. Depending on the design, these devices contain a variety of built-in functions. For example, some sensors detect vehicle entry and exit, while others require the driver to enter the parking space or vehicle license. A user interface offers the driver options, including defining the expected return time and paying appropriately.
Medical Equipment
Medical equipment automatically monitors bio constants, administers drugs. If the bio constants exceed or fall below a threshold value, it alerts the staff. As a result, it may help doctors treat the patients, monitor health issues, and save their lives.
The navigation system of a plane
The navigation system of a plane is a good instance of a real-time operating system. The main computer of an airplane is connected to most control systems such as the wing, engine, pressure controls, and safety. As a result, it is specifically built to work inside a plane and help with takeoff, landing, and emergency operations.
Advantages and disadvantages of Embedded Operating System
There are various advantages and disadvantages of an embedded operating system. Some of them are as follows:
Advantages
There are various advantages of an embedded operating system. Some of them are as follows:
- It is small in size and faster to load.
- It is low cost.
- It is easy to manage.
- It provides better stability.
- It provides higher reliability.
- It provides some interconnections.
- It has low power consumption.
- It helps to increase the product quality.
Disadvantages
There are various disadvantages of an embedded operating system. Some of them are as follows:
- It isn’t easy to maintain.
- The troubleshooting is harder.
- It has limited resources for memory.
- It isn’t easy to take a back of embedded files.
- You can’t change, improve, or upgrade an embedded system once it’s been developed.
- If any problem occurs, you need to reset the setting.
- Its hardware is limited.