Microcomputer

A microprocessor is a  general purpose central processing  until of a digital  computer system. It has  arithmetic  logical unit  control circuits and a set of registers on a signal chip. To make  it a complete systems ( called microcomputer)  we have  to add read  only  memory  (FROM)  random  access  memory  (RAM)  and number  of input / output  device  through  systems  buses  as shown in figure.

In college laboratories  we have  signal  board  microcomputers. These microcomputer have 8 to 16  bit microprocessor ROM  RAM  hex keyboard  and seven segment LED  display unit. A monitor program  is stored in ROM  less than  2 k  bytes  to interact  memory  and input/ output  devices.

A  larger  microcomputer  is known  as personal   computer used generally for  personal  or business  purpose. It is equipped with many additional special purpose devices like floppy disk drive and hard disk  drive for mass storage larger keyboard 108 or more keys CRT display monitor CD  drive etc. In these   computer operating systems  is required instead of monitor program  to interact with larger  memory and various special  purpose  inputs/ output  devices. Commonly  used operating systems  are DOS  UNIX and  many  version of Microsoft windows ( 98 ,XP , ME, etc)  such  computer  may  be used  in general  purpose  software  applications.