Designing Embedded Hardware

Embedded Computer Architecture

What a computer is used for, what tasks it must perform, and how it interacts with humans and other systems determine the functionality of the machine, and therefore its architecture, memory, and I/O.

An arbitrary desktop computer (not necessarily a PC) is shown in Figure 1-13. It has a large main memory to hold the operating system, applications, and data and an interface to mass storage devices (disks and DVD/CD-ROMs). It will have a variety of I/O devices for user input (keyboard, mouse, and audio), user output (display interface and audio), and connectivity (networking and peripherals). The fast processor requires a system manager to monitor its core temperature and supply voltages and to generate a system reset.

Large-scale embedded computers may also take the same form. For example, they may act as a network router or gateway and so will require one or more network interfaces, large memory, and fast operation. They may also require some form of user interface as part of their embedded application and, in many ways, may simply be a conventional computer dedicated to a specific task. Thus, in terms of hardware, many high-performance embedded systems are not that much different from a conventional desktop machine.

Figure 1-13. Block diagram of a generic computer

Smaller embedded systems use microcontrollers as their processor, with the advantage that ...