CPU - Word

> Computer System > Computer - Central processing unit (CPU)

1 - About

A word is a fixed-sized piece of data processed as a unit by the processor. The word size is defined in the instruction set architecture.

The term word is used for a small group of bits that are handled simultaneously by processor of a particular architecture.

A word is stored in memory one byte at a time.

The following component in a computer have generally the size of word:

Advertising

3 - Properties

3.1 - Size

It determines the unit of processing of the whole computer. ie for:

3.2 - Byte order

When a word is greater than one byte and therefore needs to be split in order to be stored in memory, the part are stored in a order called endianess. Words may be represented in big-endian or little-endian format. Memory - Byte Order - (Endian-ness) of a Word

4 - Example of 32 bits long word

32 bits (4 bytes)

5 - Full

A 32 bits register is called a fullword.

6 - Data Type

integer max size is on some computer define by the size of a word.

This limitation may cause programs to crash. For example, if a programmer using the C language incorrectly declares as int a variable that will be used to store values greater than <math>2^{15}−1<math>, the program will fail on computers with 16-bit integers. That variable should have been declared as long, which has at least 32 bits on any computer.

Advertising

7 - Documentation / Reference

computer/cpu/word.txt · Last modified: 2019/04/07 16:39 by gerardnico