Quick Revision: Core Concepts in Computer Architecture & Organization Quiz

Brush up on essential computer architecture and organization concepts with these beginner-level MCQs. This quiz covers instruction cycles, memory hierarchy, processor operations, and basic architectural types to help you prepare effectively for exams.

  1. Instruction Cycle Components

    Which of the following is NOT a part of the instruction cycle in a CPU?

    1. Fetch
    2. Decode
    3. Execute
    4. Compile

    Explanation: Compile is not a part of the instruction cycle; it is a process done before execution, converting source code to machine code. Fetch, decode, and execute are the main phases of the instruction cycle. Fetch obtains instructions from memory, decode interprets them, and execute carries them out. Compile occurs prior to these steps and does not repeat for each instruction executed.

  2. Fetching from Memory

    What is fetched from memory at the first step of the instruction cycle?

    1. Data
    2. Op code
    3. Instruction
    4. Register

    Explanation: The entire instruction, which includes the op code and operands, is fetched from memory in the first step. Fetching only data or op code would be incomplete; both are essential parts of the instruction. Registers are storage areas inside the CPU, not something fetched from memory at this step.

  3. Program Counter Function

    The program counter holds the address of which of the following?

    1. Current instruction
    2. Next instruction
    3. Last executed instruction
    4. Stack top

    Explanation: The program counter (PC) stores the memory address of the next instruction to be executed. It does not hold the addresses of the current or last instruction, as those are either being processed or already completed. Stack top refers to the top value in the stack memory, unrelated to the program counter.

  4. Instruction Decoding Unit

    Which unit is responsible for decoding the fetched instruction in a CPU?

    1. ALU
    2. Control unit
    3. Register
    4. Cache

    Explanation: The control unit decodes the instruction to determine the required operation and orchestrates the execution steps. The ALU (Arithmetic Logic Unit) performs calculations, registers hold data temporarily, and cache is used for fast data storage, not decoding instructions.

  5. Execution Result Storage

    Where is the result of execution usually stored temporarily in a CPU?

    1. Main memory
    2. Stack
    3. Register
    4. Cache

    Explanation: Registers temporarily hold execution results for fast CPU access before sending data elsewhere if necessary. Main memory, while capable of storing data, is slower and not used for immediate post-execution storage. Stack is used mainly for managing function calls, and cache is for quick data access.

  6. Instruction Cycle Name

    The instruction cycle in computer architecture is also known as the:

    1. Machine cycle
    2. Clock cycle
    3. Transfer cycle
    4. Pulse cycle

    Explanation: The instruction cycle is commonly called the machine cycle, describing the complete process from fetching to executing an instruction. Clock cycle refers to one pulse of the system clock, unrelated to full instruction execution. Transfer and pulse cycles are not standard terms for this process.

  7. Program Counter After Execution

    What usually happens to the program counter after an instruction is executed?

    1. Incremented
    2. Set to zero
    3. Reset
    4. None of these

    Explanation: After executing an instruction, the program counter is incremented to point to the address of the next instruction. It is not generally set to zero or reset, except during specific program operations like a reset or jump. 'None of these' is incorrect as incrementing is the standard behavior.

  8. Instruction Components

    An instruction in computer architecture is made up of which components?

    1. Only op code
    2. Only operand
    3. Op code and operand
    4. Op code and data

    Explanation: An instruction typically consists of an operation code (op code), which specifies the operation, and an operand, which provides the data or address to be used. Only op code or only operand would be incomplete. Data can be involved, but the standard term is operand, not data.

  9. Control Flow Instructions

    Which instruction transfers program control to a specific address during execution?

    1. Move
    2. Add
    3. Jump
    4. Multiply

    Explanation: A jump instruction alters the execution sequence by transferring program control to a designated address in memory. Move and add perform data transfer and arithmetic, while multiply is for calculations; none of these change the flow of control like a jump does.

  10. Instruction Cycle Controller

    Which unit controls the flow of the instruction cycle inside the CPU?

    1. ALU
    2. Control unit
    3. RAM
    4. Cache

    Explanation: The control unit is responsible for managing and directing each stage of the instruction cycle. While the ALU performs arithmetic and logic, RAM and cache are types of memory and do not control processes.

  11. Fastest Cache Type

    Which level of cache is typically the fastest in modern CPUs?

    1. L1
    2. L2
    3. L3
    4. RAM

    Explanation: L1 cache is closest to the CPU core and is the fastest among all cache types. L2 and L3 caches provide larger but slower storage. RAM is not a cache and is much slower in comparison to L1.

  12. Shared Cache Level

    Which cache level is usually shared among all processor cores in a multi-core CPU?

    1. L1
    2. L2
    3. L3
    4. All

    Explanation: L3 cache is commonly shared among all the cores in multi-core CPUs to facilitate data access. L1 and L2 are typically private to each core, while 'All' is incorrect as only L3 is truly shared.

  13. Smallest Memory

    Which type of memory is the smallest in size but fastest to access?

    1. L1
    2. L2
    3. L3
    4. Main memory

    Explanation: L1 cache has the smallest capacity but offers the fastest access speeds. L2 and L3 are larger, albeit slower. Main memory (RAM) is much larger and slower than any cache level.

  14. Cache Memory Role

    What is the main role of cache memory in a computer system?

    1. Store data permanently
    2. Backup data
    3. Store frequently used data
    4. Increase RAM speed

    Explanation: Cache stores frequently accessed data to speed up CPU processing. It is not used for permanent or backup storage. While it can improve system performance, it does not actually increase the speed of RAM itself.

  15. Cache Location

    Where is cache memory typically located in a computer system?

    1. RAM
    2. Hard disk
    3. CPU
    4. Motherboard

    Explanation: Cache is built directly into the CPU chip for rapid data access. It is not located in RAM, on the hard disk, or as a separate component on the motherboard, which would make access slower.