3. Hardware

Question 1

Give examples of data input and output.

Answer 1

Data output
For data output from a computer system the following options are available:
• screen display
• hardcopy using a printer or plotter
• virtual headset display
• a speaker
• writing to any of the data storage devices described earlier
• transmission on a network link.

Data input
For the input of data to a computer system the following are among the options available:
• keyboard or keypad entry by a user
• user interaction with a screen using screen icons or menus; possibly using a pointing device and possibly involving the use of a touch screen
• a user using a game controller
• a user using a scanner
• a user using a microphone in tandem with voice recognition software
• reading from any of the storage devices described earlier
transmission on a network link.

Question 2

What is an embedded system?

Answer 2

An embedded system is a computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system

Question 3

How does a graphic scanner work?

Answer 3

Graphic scanner scans full width and height of the paper and converts analogue signal received that is proportional to the intensity of reflected light from the paper.

Question 4

What types of touch screens are there?

Answer 4

1. Resistive touch screen
2. Capacitive touch screen

Question 5

What is ROM?

Answer 5

ROM (read-only memory) has specialised uses for the storage of data or programs that are going to be used unchanged over and over again. In a general-purpose system the most important use is in storing the bootstrap program. This is a program that runs immediately when a system is switched on. ROM is used in many embedded systems.

Question 6

What is RAM?

Answer 6

RAM is essentially short term memory where data is stored as the processor needs it.

Question 7

Give examples of Processor component, Primary storage and Secondary storage hardware deviced

Answer 7

Processor component: Registers
Primary Storage: Cache memory, virtual memory and main memory (RAM and ROM)
Secondary storage: Hard disk, CD, DVD, Solid state drive, flash drive, ODD (optical disk drive

Question 8

Explain the difference between Programmable ROM (PROM), Erasable Programmable ROM (EPROM) and Electrically Erasable Programmable ROM (EEPROM).

Answer 8

1. PROM can be set once, EPROM and EEPROM can be overwritten
   multiple times.
2. EPROM needs to be removed from device EEPROM can be erased in
   situ.
3. EPROM and can be erased using UV light, EEPROM can be erased
   using voltage // is flash storage .
4. EPROM must be entirely erased before rewriting, EEPROM does not
   have to be entirely erased before rewriting.