SECTION I-2: Micro-controllers for Embedded Systems

SECTION  I-2: Micro-controllers for Embedded Systems

Microprocessors and micro-controllers  are widely used in embedded system products. An embedded product is controlled by its own internal microprocessor or micro-controllers, as opposed to an external controller. In an embedded system, the micro-controllers ROM is burned with a purpose for specific functions needed for the system. A printer is an example of an embedded system because the processor inside it performs one task only; getting the data and printing it. Contrast this with a Pentium based PC or any x86 IBM compatible PC, which can be used for any number of applications such as work processor, print-server, bank teller terminal, video game player, network server, or internet terminal. A PC can also load and run software for a variety of applications. A PC can perform myriad tasks is that it has RAM memory and an operating system that loads the application software into RAM and lets the CPU run it. In an embedded system, only one application software is burned into ROM. An x86 PC contains or is connected to various embedded products such as the keyboard, printer, modem, disk controller, sound cards, CD-ROM driver, mouse etc. Each one of these peripherals has a micro-controller inside it that performs only one task of finding the mouse's position and sending it to the PC.