Computer Memory Concepts Quiz

Computer Science Paper 1 - Computer Systems

• Examination paper details:

  • Paper: 1 Computer Systems
  • Exam code: 0478/12
  • February/March 2024
  • Duration: 1 hour 45 minutes
  • Total marks: 75
  • Instructions include using a black or dark blue pen, writing your details, and not using calculators

• Data Representation (Binary):

  • Computers use binary (1s and 0s) to represent data.
  • Computers have switches and gates that are either on or off, which corresponds to 1 and 0.
  • ASCII stands for American Standard Code for Information Interchange.
  • The ASCII denary number for 'N' is 78.
  • Students need to find the ASCII denary number for 'Q' (Answer: 81)

• Data Types - Character Representation:

  • Explain how the word 'RED' is represented using a character set.
  • 'RED' would be represented sequentially by codes from the character set (ASCII).

• Sound Recording:

  • Higher sampling resolution leads to a more accurate sound recording. This means more samples per second of audio are stored, allowing the recording to represent the exact nature of the recorded sound accurately.
  • Other ways to improve sound recording accuracy include better microphones, better recording quality, lower noise, and better sampling techniques.
  • Different ways to improve sound quality include better microphones or other techniques.

• CPU Registers:

  • The CPU has registers such as the program counter (PC), memory address register (MAR), memory data register (MDR), accumulator (ACC), and current instruction register (CIR).
  • PC stores address of next instruction.
  • MAR stores instruction of running program.
  • MDR stores data passed from PC.
  • ACC stores calculation result.
  • CIR stores currently exectued instruction.
  • Two incorrect statements about CPU registers are provided, which need to be identified and corrected.

• CPU Performance:

  • A 3.5 GHz processor means the CPU can execute 3.5 billion cycles per second (cycles per second).
  • The number of cores affects the performance of the CPU. More cores allow for more instructions to be executed in parallel, leading to faster processing.
  • The amount of cache affects the performance of a computer because a larger cache means that more commonly-used/requested data is readily available, which reduces transfer time between different storage locations, resulting in faster retrieval of data and quicker instructions.

• Primary Storage (RAM):

  • RAM (Random Access Memory) is a primary storage location.
  • It stores data that's currently being used by the computer.
  • When the power is switched off, the data in RAM is lost.

• Primary Storage (ROM):

  • ROM (Read-Only Memory) stores instructions for booting up a computer.
  • Other data regularly stored in ROM includes BIOS (Basic Input/Output System) programs.

• Virtual Memory:

  • Virtual memory is used to manage memory when RAM is full.
  • The purpose of virtual memory is to increase the available memory that can be used by the computer, even without having significantly more physical RAM than what's required in a given situation.

• Operating System (OS):

  • The operating system (OS) functions include managing memory, managing peripherals, allowing application software to run on a computer, handling interrupts.
  • The OS handles interrupts to manage different actions and processes. Interrupts are events that need immediate attention from the OS.
  • An example of an interrupt is a key press.

• Webpage Display (URLs):

  • A diagram annotated to show the process of entering a URL until the webpage is displayed on the user’s screen needs to be drawn.

• Digital Currency (Blockchains, Encryption):

  • Blockchains are digital ledgers containing information about transactions.
  • Encryption keeps data secure during transmission.

• Error Checking (Parity):

  • Parity bit checking is a method used to check for errors in data transmission.
  • A parity byte is added to the transmitted data to indicate even or odd parity.

• Data Transfer on the Internet:

  • Data is encrypted to keep data secure when transmitted over the internet.
  • Data is transmitted through packet switching, where data is divided into packets.
  • Packets include information in a header that's used for routing.
  • Routers route packets based on information in the header.

• Number Systems:

  • Converting between denary, binary, and hexadecimal number systems.

• Two's Complement:

  • Two's complement integers represent positive and negative numbers.

• Logical Shifts on Binary Integers:

  • Logical right shift of four places on a binary integer reduces the integer by 2⁴ (16).

Test your knowledge of computer memory concepts including RAM and ROM. This quiz explores definitions, purposes, and differences between various types of memory in computer systems. Discover how these elements contribute to overall computer functionality.