Embedded systems consist of hardware and software and can operate independently. embedded moduleHowever, the embedded system is very different from the general computer processing system, and it cannot realize the mass storage function because there is no matching mass media. Most of the storage media used are E-PROM, EEPROM, etc. The software part is based on API programming interface as the core of the development platform. So, what are the features of the embedded system?
Embedded control system hardware and software companies must be able to analyze and select according to the specific application research tasks, power consumption, cost, volume, reliability, processing technology capabilities, etc. as indicators. The core of the embedded system is the system design software and application management software, due to the limited data storage space, thus requiring compact and reliable software code, and real-time in strict accordance with the requirements.
From the structure, the embedded system is a computer system with integrated hardware and software, which can work independently; from the appearance, the embedded system is like a "programmable" electronic device; from the function, it is a controller that controls the target system (host object) to make it intelligent. From the point of view of users and developers, compared with ordinary computers, embedded systems have the following characteristics.
(1) High specificity. Since embedded systems are usually targeted for specific applications, the hardware and software of embedded systems, especially software, are designed for specific user groups and usually have a certain degree of specificity.
(2) Size miniaturization. Embedded computers integrate many tasks done by boards in general-purpose computer systems into the chip, which facilitates miniaturization and makes it easy to embed the embedded system into the target system.
(3) Good real-time performance. Embedded operating system can be widely used in enterprise production management process quality control, data and information acquisition, transmission network communication and other occasions, mainly is used to effectively control between the host object, so there are more or less real-time requirements for the embedded system. For example, the real-time requirements for embedded systems in weapons, control environment systems in certain industrial internal control devices, etc. are extremely high. Some student systems are not very demanding in real time, for example, the development in recent years as well as the faster handheld computer, etc. But the overall design, real-time is the universal use of embedded systems requirements, is the designer and user should focus on the need to consider a very important factor indicators.
(4) good cutting. According to the characteristics of embedded systems, embedded systems suppliers should provide a variety of hardware and software to choose from, and strive to achieve higher performance on the same silicon area. In order to be more competitive in a particular application.
(5) High reliability. Because some embedded systems are involved in something critical, such as the critical quality of the products they are accused of, the security of their personal devices, or even state secrets, and also because some embedded systems' hosts work in unattended places, such as high-risk industrial environments and harsh field environments where monitoring equipment is used. Therefore, compared with traditional systems, embedded systems require higher reliability.
(6) Low power consumption. Many embedded systems are hosted by small applications, such as cell phones, MP3, digital cameras, etc. , can not be equipped with AC power or a larger power supply, so low power consumption has been the goal of the embedded system to pursue.
(7) embedded control system itself does not have the ability to self-development technology, must be developed through the use of general-purpose computer network platform. Embedded systems can be designed to complete their own later, ordinary users usually we do not have a solution to the program or hardware structure problems to modify, must have a set of development tools and environment in order to continue to carry out.
(8) embedded systems usually use the method of "hardware and software co-design". In the early embedded system design method, often using the "hardware first" principle, that is, first in the case of a rough estimate of the software task requirements for hardware design and implementation, and then in the hardware platform for software design. If the traditional design approach is used, once problems are found during testing and the design needs to be modified, the entire design process will be repeated, which has a significant impact on the cost and design cycle. The design of the system relies heavily on the experience of the designer.
Since the 1990s, with the development of electronics, chips and other related technologies, a software and hardware co-design approach has emerged in the design and implementation of embedded systems, i.e., a unified approach and tools are used to describe, synthesize and verify the software and hardware. Under the guidance of the system target requirements, the system software and hardware functions and available resources are analyzed comprehensively, and the software and hardware architecture is designed collaboratively to maximize the system software and hardware capabilities. In order to avoid the drawbacks caused by the independent design of hardware and software structures, an optimized design scheme with high performance and low cost is proposed.By:Carmen