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Deline ALU control unit
mámory
unit
Explain
brief
a MICR
& Keyboard
o mouse
do Light pen
printer
A Monitor
Answers
which class are you studying sister / brother
Explanation:
An arithmetic logic unit (ALU) is a digital circuit used to perform arithmetic and logic operations. ... The control unit tells the ALU what operation to perform on that data, and the ALU stores the result in an output register. The control unit moves the data between these registers, the ALU, and memory
Memory unit is the amount of data that can be stored in the storage unit. This storage capacity is expressed in terms of Bytes.
Mouse
Mouse is most popular Pointing device. It is a very famous cursor-control device. It is a small palm size box with a round ball at its base which senses the movement of mouse and sends corresponding signals to CPU on pressing the buttons.
Generally it has two buttons called left and right button and scroll bar is present at the mid. Mouse can be used to control the position of cursor on screen, but it cannot be used to enter text into the computer.
Advantages
Easy to use
Not very expensive
Moves the cursor faster than the arrow keys of keyboard.
Keyboard
Most common and very popular input device is keyboard. The keyboard helps in inputting the data to the computer. The layout of the keyboard is like that of traditional typewriter, although there are some additional keys provided for performing some additional functions.
Keyboard is of two sizes 84 keys or 101/102 keys, but now 104 keys or 108 keys keyboard is also available for Windows and Internet.
Light Pen
Light pen is a pointing device which is similar to a pen. It is used to select a displayed menu item or draw pictures on the monitor screen. It consists of a photocell and an optical system placed in a small tube.
When light pen’s tip is moved over the monitor screen and pen button is pressed, its photocell sensing element detects the screen location and sends the corresponding signal to the CPU.
Magnetic Ink Card Reader (MICR)
MICR input device is generally used in banks because of a large number of cheques to be processed every day. The bank’s code number and cheque number are printed on the cheques with a special type of ink that contains particles of magnetic material that are machine readable.
This reading process is called Magnetic Ink Character Recognition (MICR). The main advantage of MICR is that it is fast and less error prone
Monitors
Monitor commonly called as Visual Display Unit (VDU) is the main output device of a computer. It forms images from tiny dots, called pixels that are arranged in a rectangular form. The sharpness of the image depends upon the no. of the pixels.
There are two kinds of viewing screen used for monitors.
Cathode-Ray Tube (CRT)
Liquid Cristal Display (LCD)
Plasma Display
Printers
Printer is the most important output device, which is used to print information on paper.
There are two types of printers
Impact Printers
Non-Impact Printers
Impact Printers
The printers that print the characters by striking against the ribbon and onto the paper are called impact printers.
Characteristics of Impact Printers are following
Very low consumable costs
Impact printers are very noisy
Useful for bulk printing due to low cost
There is physical contact with the paper to produce an image
These printers are of two types
These are of further two types
Dot Matrix Printer(DMP)
Daisy Wheel