Fundamentals of Computers
Answer the following questions
Part – II
1. What are the parameters which influence the characteristics of a microprocessor?
A Microprocessor’s performance depends on the following characteristics:
(i) Clock speed
(ii) Instruction set
(iii) Word size
2. What is an instruction?
Answer: A command which is given to a computer to perform an operation on data is called an instruction.
3. What is a program counter?
Answer: The Program Counter (PC) is a special register in the CPU which always keeps the address of the next instruction to be executed.
4. What is HDMI?
Answer: High-Definition Multimedia Interface is an audio/video interface which transfers the uncompressed video and audio data from a video controller, to a compatible computer monitor, LCD projector, digital television etc.
5. Which source is used to erase the content of a EPROM?
is used to erase the content of a EPROM.
Part – III
1. Differentiate Computer Organization from Computer Architecture.
(i) Computer Organization deals with the hardware components that are transparent to the programmer.
(ii) Computer architecture deals with the engineering considerations involved in designing a computer.
2. Classify the microprocessor based on the size of the data.
Answer: Microprocessors can process instructions. The microprocessors can be classified as follows based on the size of the data.
(i) 8-bit microprocessor
(ii) 16-bit microprocessor
(iii) 32-bit microprocessor
(iv) 64-bit microprocessor
3. Write down the classifications of microprocessors based on the instruction set.
Answer: The two types of microprocessors wich are based on their instruction sets.
(i) Reduced Instruction Set Computers (RISC)
(ii) Complex Instruction Set Computers (CISC)
4. Differentiate PROM and EPROM.
(i) Programmable Read only memory.
(ii) It is also a non-volatile memory on which data can be written only once.
(iii) PROM burner is used to write data to a PROM chip.
(i) Erasable Programmable Read only memory.
(ii) It is also a nono-volatile memory and a special type of memory.
(iii) EPROM serves as a PROM, but the content can be erased using ultraviolet rays
5. Write down the interfaces and ports available in a computer.
(i) Serial Port
(ii) Parallen Port
(iii) USB 3.0
(iv) VGA Connector
(v) Audio Plugs
(vi) PS/2 Port
(vii) SCSI Port
(viii) High Definition Multimedia Interface (HDMI).
6. Differentiate CD and DVD
(i) Expansion is Compact-Disk
(ii) A standard CD can store about 700 MB of Data.
(iii) CD players cannot play DVDs.
(iv) It stores upto 80 min of audio.
(i) Expansion is Digital Versatile Disc.
(ii) A standard DVD can hold 4,7 GB of data.
(iii) DVD players can play CDs.
(iv) It can range from 4.7 GB to 17.08 GB.
7. How will you differentiate a flash memory and an EEPROM?
Answer: Flash memory devices:
(i) Flash memory is an electronic (solid-state) non-volatile computer storage medium that can be electrically erased and reprogrammed.
(ii) Flash memories can be used in personal computers, Personal Digital Assistants (PDA), digital audio players, digital cameras and mobile phones.
(iii) Flash memory offers fast access times. The time taken to read or write a character in memory is called access time.
(iv) Examples for Flash memories are pen drives, memory cards etc.
(ii) Electrically Erasable Programmable Read Only Memory can be erased by exposing it to an electrical charge.
(ii) EEPROM is non-volatile.
(iii) EEPROM is slower in performance.
Part – IV
1. Explain the characteristics of a microprocessor.
Answer: A Microprocessor’s performance depends on the following characteristics:
(i) Clock speed
(ii) Instruction set
(iii) Word size
(i) Clock Speed
Every microprocessor has an internal clock that regulates the speed at which it executes instructions. The speed at which the microprocessor executes instructions is called clock speed. Clock speed is measured in MHz (Mega Hertz) or in GHz (Giga Hertz).
(ii) Instruction set: A command which is given to a computer to perform an operation on data is called an instruction. Basic set of machine level instructions that a microprocessor is designed to execute is called as an instruction set. This instruction set carries out the following types of operations:
1. Data transfer
2. Arithmetic operations
3. Logical operations
4. Control flow
(iii) Word Size :
The number of bits that can be processed by a processor in a single instruction is called its word size. Word size determines the amount of RAM that can be accessed by a microprocessor at one time and the total number of pins on the microprocessor. Total number of input and output pins in turn determines the architecture of the microprocessor.
2. How the read and write operations are performed by a processor? Explain.
Answer: (i) The Central Processing Unit(CPU) has a Memory Data Register (MDR) and a Memory Address Register (MAR).
(ii) The Memory Data Register (MDR) keeps the data which is transferred between the Memory and the CPU. The Program Counter (PC) is a special register in the CPU which always keeps the address of the next instruction to be executed.
(iii) A bus is a collection of wires used for communication between the internal components of a computer.
(iv) The address bus is used to point a memory location. A decoder, a digital circuit is used to point to the specific memory location where the word can be located.
(v) The read operation fetches data from memory and transfers to MDR. A single control line performs two operations like read write using 1 or O.
(vi) Also, the write operation transfers data from the MDR to memory.
(vii) The word in the RAM has the same size (no. of bits) as the Memory Data Register (MDR).
(viii)The data bus has eight parallel wires to transfer data either from MDR to word or word to MDR based on the control (Read or write).
(ix) This control line is labeled as R/W, which becomes 1 means READ operation and 0 means WRITE operation. The content of MDR and the Word before the READ operation. Also figure shows the content of MDR and the Word after the READ operation.
(x) The read operation transfers the data (bits) from memory word to data register. The write operation transfers the data (bits) from memory data register to word.
3. Arrange the memory devices in ascending order based on the access time.
Answer: A memory is just like a human brain. It is used to store data and instructions. Computer memory is the storage space in the computer, where data and instructions are stored. There are two types of accessing methods to access (read or write) the memory.
They are sequential access and random access. In sequential access, the memory is accessed in an orderly manner from starting to end. But, in random access, any byte of memory can be accessed directly without navigating through previous bytes. Different memory devices are arranged according to the capacity, speed and cost as shown in Figure.
4. Explain the types of ROM.
Answer: Read-only memory (ROM) :
(i) Read only memory refers to special memory in a computer with pre-recorded data at manufacturing time which cannot be modified.
The stored programs that start the computer and perform diagnostics are available in ROMs.
(ii) ROM stores critical programs such as the program that boots the computer. Once the data has been written onto a ROM chip, it cannot be modified or removed and can only be read.
(iii) ROM retains its contents even when the computer is turned off. So, ROM is called as a non-volatile memory.
Programmable Read-Only Memory (PROM) :
(i) Programmable read-only memory is also a non-volatile memory on which data can be written only once. Once a program has been written onto a PROM, it remains there forever.
(ii) Unlike the main memory, PROMs retain their contents even when the computer is turned off.
(iii) PROM is manufactured as a blank memory, whereas a ROM is programmed during the manufacturing process itself. PROM programmer or a PROM burner is used to write data to a PROM chip. The process of programming a PROM is called burning the PROM.
Erasable Programmable Read-Only Memory (EPROM)
(i) Erasable Programmable Read-Only Memory is a special type of memory which serves as a PROM. The content can be erased using ultraviolet rays.
(ii) An EPROM differs from a PROM. PROM can be written only once and cannot be erased.
(iii) EPROMs are used widely in personal computers because they enable the manufacturer to change the contents of the PROM to replace with updated versions or erase the contents before the computer is delivered.
Electrically Erasable Programmable Read-Only Memory (EEPROM)
(i) Electrically Erasable Programmable Read-Only Memory can be erased by exposing it to an electrical charge.
(ii) Like other types of PROM, EEPROM retains its contents even when the power is turned off. Comparing with all other types of ROM, EEPROM is slower in performance.