According to the definition of the British Institute of electrical engineers, embedded systems are control, monitoring or auxiliary equipment, machines or equipment used for plant operation. Small series of the following for you to sort out the functions of the embedded operating system, I hope to help you.
Functions of embedded operating system:
The embedded operating system is relative to the general operating system. It has the most basic functions of the general operating system (Embedded Linux system), such as task scheduling, synchronization mechanism, interrupt processing, file processing and so on
1. Construct a virtual machine platform which is easy to program
Embedded operating system constitutes a virtual machine platform. EOS encapsulates the underlying hardware details and provides an abstract programming interface for the software (such as middleware software and various application software) running on it. Software development is carried out on this programming interface, not directly dealing with the machine hardware layer. The programming interface provided by EOS is actually the system call function provided by the operating system.
2. The manager of system resources
Embedded operating system is a system resource manager, responsible for the management of various software and hardware resources in the system, such as processor, memory, various I / O devices, files and data, so that the whole system can operate efficiently and reliably.
The goal of EOS running in embedded environment is to complete a certain or limited function, rather than a general-purpose operating system. Therefore, there are strict restrictions on performance and real-time performance. Energy consumption, cost and reliability are usually important factors affecting the design. It requires less resources and is suitable for running in limited storage space. It requires that the system function can be designed according to the design requirements of the product We need to cut and adjust.
All EOS have a kernel, which is a component of the system. It includes four functional modules: task management, storage management, input / output (I / O) device management and file system management. Among them:
Task management: describe and manage the running software in the embedded system, and complete the allocation and scheduling of processor resources;
Storage management: used to improve the utilization of memory, facilitate the use of users, and provide enough storage space;
I / O device management: facilitate the use of devices, improve the utilization of CPU and I / O devices;
File management: to solve the storage, sharing, confidentiality and protection of file resources.
EOS of different embedded systems may contain different components, kernel design may also be different, depending on the design of the system and the actual application requirements.
The characteristics of embedded operating system are as follows
① Portability. Open and scalable architecture.
② Strong real-time. EOS has strong real-time performance and can be used in all kinds of equipment control.
③ Unified interface. Provide various device driver interfaces.
④ Easy to operate, simple, provide friendly GUI, graphical interface, the pursuit of easy to learn and easy to use.
⑤ Provide powerful network functions, support TCP / IP protocol and other protocols, provide TCP / UDP / IP / PPP protocol support and unified MAC access layer interface, and reserve interfaces for various mobile computing devices.
⑥ Strong stability and weak interaction. Once the embedded system starts to run, it doesn’t need too much user intervention, so EOS, which is responsible for system management, has strong stability. Generally, the user interface of embedded operating system does not provide operation commands, it provides services to user programs through system call commands.
⑦ Solidify the code. In embedded system, embedded operating system and application software are solidified in ROM of embedded system computer. Auxiliary memory is rarely used in embedded system. Therefore, the file management function of embedded operating system should be easily disassembled, and all kinds of memory file systems should be used.
⑧ Better hardware adaptability, that is, good portability.