Embedded systems are everywhere: homes, offices, cars, factories, hospitals, plans and consumer electronics. Their large numbers and new complexity require a new design approach that emphasizes high-level tools and hardware and software offsets, rather than low-level assembly language programming and logical design. This book introduces the traditionally diverse fields of software and hardware design into a new unified approach. It encompasses trends and challenges, introduces the design and use of single purpose processors (hardware) and general purpose processors, describes memories and buses, illustrates hardware / software offsets using an example of a digital camera And discusses advanced models of computing, control systems, chip technologies and modern design tools. The table of contents of the ESD is shown below. In addition, the ESD does not intentionally cover the details of any particular processor, largely because of the variety of configurations used in courses of embedded systems.
An embedded system is a computer system with a dedicated function within a larger mechanical or electrical system, often with constraints of real-time computing. It is embedded as part of a complete device that often includes hardware and mechanical parts. Integrated systems control many devices in common use today. Ninety-eight percent of all microprocessors are manufactured as components of embedded systems.
Examples of typically embedded computer properties compared to general purpose counterparts are low power consumption, small size, rugged operating ranges, and low cost per unit. This occurs at the price of limited processing resources, which makes them much more difficult to program and interact with. However, by building intelligence mechanisms at the top of the hardware, taking advantage of possible existing sensors and the existence of a network of embedded units, the available resources at the unit and network level can be optimally managed. For example, intelligent techniques can be designed to manage the energy consumption of embedded systems.
Modern embedded systems are often based on microcontrollers (ie CPUs with integrated memory or peripheral interfaces), but common microprocessors (using external chips for memory circuits and peripheral interfaces) are also common, especially in more complex systems . In any case, the processor (s) used can be types ranging from the general purpose to those specialized in certain types of calculations, or even customized for the application in question. A common standard class of dedicated processors is the digital signal processor (DSP).
Since the integrated system is dedicated to specific tasks, design engineers can optimize it to reduce the size and cost of the product and increase reliability and performance. Some embedded systems are mass-produced, benefiting from economies of scale.
Integrated systems range from portable devices such as digital clocks and MP3 players to large stationary facilities such as traffic lights, factory controllers and largely complex systems such as hybrid vehicles, magnetic resonance imaging and avionics. The complexity varies from low, with a single microcontroller chip, to very high with multiple units, peripherals and networks mounted inside a large chassis or enclosure.
