Basic Computer Organization: Input Unit

BASIC COMPUTER ORGANIZATION

INPUT UNIT

Data and instructions must enter the computer system, before any computation can be performed on the supplied data. This task is performed by the input unit, which links the external environment with the computer system. Data and instruction enter input units in forms, which depend upon the particular device used. For example data are entered from a keyboard in a manner similar to typing, and this differs from the way in which data are entered through a scanner, which is another type of input device. However, regardless of the form in which they receive their inputs, all input devices must transform the input data into the binary cods, which the primary memory of a computer is designed to accept. This transformation is accomplished by units called input interfaces. Input interfaces are designed to match the unique or electrical characteristics of input devices, to the requirements of the computer system.

In  short, the following functions are performed by an input Unit:

It accepts (or reads) the instructions and data from outside world.

It converts these instructions and data in computer acceptable form.

It supplies the converted instructions and data to the computer system for further processing.