Embedded Systems are the crucial components of the modern compacted devices with multifunction capabilities. Embedded systems are specific computer programs that combine the functions of specially designed softwares and hardwares and are completely encapsulated by the devices that they control. An embedded system has specific requirements and performs pre-defined tasks, unlike a general-purpose personal computer. An embedded system is a programmed hardware device. A programmable hardware chip is the platform and it is programmed with particular applications. Embedded systems are a combination of hardware and software which facilitates mass production and a host of applications.
Embedded systems constitute the widest possible use of computer systems.They include all computers specifically intended as special-purpose computers. Examples of embedded systems range from a portable music player, to real-time control of systems like the space shuttle. They are identified by their functions.The majority of commercial embedded software systems are designed to perform selected functions. These systems have to overcome resource constraints and system specifications. These systems meet their real-time constraints with a combination of special purpose hardware and software custom-developed to cope with the system requirements.
The embedded processor chip has the freedom to determine the data route , handle graphics and animation requirements and almost the entire functionalities of the device in which it is embedded. This allows the architecture of an embedded system to be simple and straight forward.For embedded systems, a real-time operating system is very essential to enable it to work efficiently within the resources parameters. The softwares specially developed for embedded hardware systems, especially those without a disk drive are named firmwares. Programs on an embedded system often run with real-time constraints with limited hardware resources. In many cases there are no disk drive, operating system, keyboard or screen. The software may not have anything remotely like a file system, or if one is present, a flash drive may replace rotating media. If a user interface is present, it may be a small keypad and liquid crystal display.
Embedded systems are normally resident in machines that are expected to run continuously for years without errors. Therefore the software and Firmware is usually developed and tested very rigorously and meticulously. Embedded systems generally avoid mechanical moving parts such as Disk drives, switches or buttons because these are unreliable compared to solid-state parts such as Flash memory. Solid State electronic components form the major part of a device with an embedded system.
The embedded system must have the unique quality and functionality of being able to restart itself even if catastrophic data corruption has taken place. This is usually accomplished with a standard electronic part called a watchdog timer that resets the computer unless the software periodically resets the timer. Embedded systems today rely on trusted Chip and processor makers like Intel, AMD and the like. Embedded softwares are being developed by developers who deploy time-tested methods like compilers,assemblers and debuggers to develop embedded system software.
A wide range of embedded systems exists on the market. Many products that feature embedded systems are small, relatively inexpensive and have a short lifetime of a few years before the next-generation product replaces them. Examples are mobile phones and other home electronics. In contrast, large, expensive and complex capital equipment, such as telephone switches, automobiles, airplanes, and industrial machines, are often safety-critical and in operation for several decades. All embedded systems, however, form part of a larger product. The buyer is primarily interested in the benefits the product brings and not in the embedded system. The emergence of embedded systems in devices has resulted in a dramatic increase in products incorporating Embedded Software. The most recent generation of embedded systems relies heavily on embedded software. As a matter of fact, many of their features, which used to be controlled by electronics or mechanical components until a few years ago, are now software controlled. Current trends reveal that functionality that traditionally was implemented in hardware is now implemented in software. The reliance of specially developed software for embedded systems has led to the mushrooming of companies specialising in embedded software develoment .
Embedded systems are going to be the focus of intensive and aggressive development in the years to come. With the world going in for devices that are compact and palm-sized, the need for advanced microporcessors and embedded softwares is huge. Embedded software developers and embedded hardware manufacturers are going to revel in the boom time that would witness a new peak in global demands for these specialised hardware-software combinations.