Microprocessors

Inside of the mysterious box that perches ominously on your desk is one of

the marvels of the modern world. This marvel is also a total enigma to most of

the population. This enigma is, of course, the microprocessor. To an average

observer a microprocessor is simply a small piece of black plastic that is found

inside of almost everything.

In How Microprocessors Work they are defined as a computer's central

processing unit, usually contained on a single integrated circuit (Wyant and

Hammerstrom, 193). In plain English this simply means that a microprocessor is

the brain of a computer and it is only on one chip. Winn L. Rosch compares them

to being an electronic equivalent of a knee-joint that when struck with the

proper digital stimulus will react in the exact same way each time (Rosch,37).

More practically a microprocessor is multitudinous transistors squeezed onto as

small a piece of silicon as possible to do math problems as fast as possible.

Microprocessors are made of many smaller components which all work

together to make the chip work. A really good analogy for the way the inner

workings of a chip operate can be found in How Microprocessors Work. In their

book, Wyant and Hammerstrom describe a microprocessor as a factory and all of

the inner workings of the chip as the various parts of a factory (Wyant and

Hammerstrom, 71-103). Basically a microprocessor can be seen as a factory

because like a factory it is sent something and is told what to do with it. The

microprocessor factory processes information. This most basic unit of this

information is the bit. A bit is simply on or off. It is either a one or a zero.

Bits are put into 8 bit groups called bytes. The number 8 is used because it is

offers enough combinations to encode our entire language (2^8=256). If only 4

bits are used only (2^4=16) combinations would be possible. This is enough to

encode 9 digits and some operations. (The first microprocessors powered

calculators) A half byte is called a nibble and consists of 4 bits. In the world

of computer graphics the combination of bits is easier seen. In computer

graphics bits are used to make color combinations, thus with more bits more

colors are possible. Eight bit graphics will display 256 colors, 16 bit will

display 65,536, and 24 bit graphics will display 16.7 million colors. The bus

unit is described as the shipping dock because it controls data transfers, and

functions between the individual pieces of the chip. The part of the chip that