Input Output and Memory devices

 Chapter 2

Input Output and Memory devices

(Important  repeated questions from previous year question papers)

1. Define Cache Memory?(Model Question paper)

• The cache is a small amount of high speed memory present between primary memory and CPU.It holds the most recent data and instructions
• There are two levels of cache memory, L1 and L2.
• L1 is present inside the CPU and L2 on mother board

2.Different types of ROM?(Board Exam 2018)

1. PROM (Programmable read-only memory) – It can be programmed by user. Once programmed, the data and instructions in it cannot be changed.
2. EPROM (Erasable Programmable read only memory) – It can be reprogrammed. To erase data from it, expose it to ultra violet light. To reprogram it, erase all the previous data.
3. EEPROM (Electrically erasable programmable read only memory) – The data can be erased by applying electric field, no need of ultra violet light. We can erase only portions of the chip.

2. Compare RAM and ROM.

•  RAM stands for Random Access Memory whereas Rom Stands for Read Only Memory
• RAM memory is volatile which means data will be present till the power supply is present whereas ROM is non-volatile which means data is permanent and will be present even when power supply is not present
• RAM is used to store dta that CPU needs for current processing whereas ROM is used to store data that is needed to bootstrap the computer.
• RAM data can be read,erased and modified whereas ROM data can only be read.
• RAM is higher in speed whereas ROM is slower than RAM.

3.compare the differences between Static RAM and Dynamic RAM

• SRAM stores information as long as the power is supplied.DRAM stores data for a very short period of time and and requires reloading of data every 2 milliseconds
• SRAM is faster whereas DRAM is comparatively slower than SRAM
• SRAM does not require refreshing whereas DRAM needs to be refreshed periodically
• SRAM is expensive and consumes more power whereas DRAM is less expensive and consumes less power.

4.Give the difference between volatile and non volatile memory

• The volatile memory stores data and computer programs that the CPU may need in real-time, and it erases them once a user switches off the computer. Cache memory and RAM are types of Volatile memory. 
• Non-volatile memory, on the other hand, is static. It remains in a computer even after a user switches it off. HDD and ROM are types of non-volatile memory.

5.Give the application of a) OCR b) OMR c) MICR devices

• a) OCR-To recognise alphabetic and numeric characters printed on paper.
•  b) OMR -Used  in applications  like objective type answer paper evaluation where large number of candidates appear, time sheet of factory employees etc.
• c) MICR devices-Is widely used in banks to process cheques.The use of MICR eliminates manual error,saves time, ensures security and accuracy of data.

6. Expand a) OCR (Board exam question 2014, 2016)

• OCR-Optical Character Recognition.

7. Expand a) OCR b) OMR c) MICR

• OCR-Optical Character Recognition.(2014, 2016)
• OMR-Optical Mark Recognition.
• MICR-Magnetic Ink Character recognition.

8. What is printer? Explain the types of printers.

• Printer is an output device that prints text or images on other paper or media(like transparencies).By printing a hard copy is created
• Printers are classified into two main types: Impact printers and Non-impact printers.
• Impact printers print by striking device against inked ribbon using a print head which containing a number of metal pins. Examples of impact printer are  line printer, dot matrix printer
• Non-impact printers do not use striking device and form characters and images without direct physical contact between the printing mechanism and the paper.Example  are laser printer, ink-jet printer

9. Expand the term MICR.

MICR stands for Magnetic Ink Character Reader/Recognition.Magnetic Ink Character Reader enables special characters printed in magnetic ink to be read and input rapidly to a computer. MICR is used extensively in banking because magnetic-ink characters are difficult to forge and are therefore ideal for marking and identifying cheques.

10.Explain non-impact printer?(2013)

Non-impact printers form characters and images without direct physical contact between the printing mechanism and the paper. Examples for non-impact printers are inkjet printers, thermal printer and laser printer.For example, inkjet printers spray tiny drops of ink onto the page, while laser printers have a cylindrical drum that rolls electrically charged ink onto the paper.

11. Give any three characteristics of non-impact printers.(2014)

• They are quiet as there is no striking mechanism
• They produce high quality graphics
• Possess the ability to change type faces automatically

12.Give characteristics of impact printers(2014)

• Physical contact is there as it  prints by striking device against inked ribbon
• Due to being  robust and low cost it is useful in bulk printing applications
• Mechanical in nature so it tends to be slow.
• They do not support transparencies.
• Ideal for printing multiple copies because they can easily print through many layers of paper.

13.Explain impact printer?Give an example?(2015)

Impact printers are printers that print by  striking device against an inked ribbon.It uses aprint head containing a number of metal pins which strike an inked ribbon placed between print head and paper

Examples are Line Printers,Dot-matrix printer

14.. Write a short note on keyboard and MOUSE devices. 

The keyboard is a standard input device. It is used to input data and programs to the computer. It has alphabets, numeric and symbol keys. It has special keys including function keys, control keys, and arrow keys. Keyboards are connected to the computer through cables or wireless. The ergonomic keyboard, virtual keyboard, and compact keyboard are a few other special types of keyboards.

The mouse is an input device used to point to a particular place on the screen and select it in order to perform one or more actions. It can be used to select menu commands, size windows, start programs, etc. The most common kind of mouse has left and right buttons on top. The left mouse button is normally used to select the items on the screen. The different types of are mechanical mouse, opto-mechanical mouse, and optical mouse.

15.What do you mean by soft copy?
A soft copy is an electronic copy of data viewed on a computer’s display screen or transmitted as an e-mail attachment.

16.What is a hard copy?
A hard copy is a physical reproduction or representation of the data, such as a printed page or photograph.

17.What is the difference between hard copy and soft copy?(2016)

A hard copy is a physical reproduction or representation of the data, such as a printed page or photograph. whereas A soft copy is an electronic copy of data viewed on a computer’s display screen or transmitted as an e-mail attachment.

Expand MOUSE?(2015)

MOUSE stands for Manually Operated User Selection Equipment. It is the equipment attached to a computer system and works as a cursor in a computer or laptop.

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