Word addressable and byte addressable

[Quote from Wikipedia]

Http://en.wikipedia.org/wiki/Byte_addressing

 

Byte addressing refers to hardware ubuntures which support accessing individual bytes of data rather than only larger units called words.

The basic unit of digital storage is called a bit. in most common computer ubuntures, 8 bits are grouped together to form a byte. byte addressable memory refers to ubuntures where data can be accessed 8 bits at a time, irrespective of the width of the data and address buses.

Please common ubuntures can address more than 8 bits of data at a time. for example, the intel processor SX processor can handle 16-bit (two-byte) data, since data is transferred over a 16-bit bus. however, data in memory may be of various lengths. A 64-bit architecture machine might still need to access byte-sized data over its 64-bit address line. such memory, which is accessible in 8-bit segments, is called byte-addressable memory.

 

[Quote from Wikipedia]

Http://en.wikipedia.org/wiki/Byte_addressing

 

"Word-addressableIs a computer science term.

In computer science, a word is an ordered set of bytes or bits (typically 2 bytes, or 16 bits) that is the normal unit in which information may be stored, transmitted, or operated on within a given computer.

Typically, if a processor has a fixed-length instruction set, then the instruction length equals the word length.

 

 

E. g: 26 bit address line, 16 Bit Data Bus.

When access in byte-addressable mode, it can access maximum 128 MB data

When access in word-addressable mode, it can access maximum 256 MB data