AL-404 Computer Organization & Architecture - Jun 2026 Question Paper

Under each question, How to answer lists the points an answer should cover, outlined by CampusPrep from the syllabus. Check the details against your textbook.

1. 7 Marks
   aExplain Stack Organization in detail. Discuss PUSH and POP operations with suitable examples and diagrams.
   How to answer

   • Definition of stack and stack pointer, LIFO principle and memory organization
   • PUSH operation steps with example
   • POP operation steps with example
   • Block diagram of stack organization
2. 7 Marks
   bExplain the Instruction Cycle in detail with a neat flowchart.
   How to answer

   • Definition of instruction cycle
   • Phases: fetch, decode, execute with steps
   • Flowchart showing flow between phases
   • Role of PC, IR and control signals
3. 7 Marks
   aExplain any FOUR addressing modes with suitable examples.
   How to answer

   • Definition of addressing mode
   • Any four modes: immediate, direct, indirect, register, etc. with format
   • Example instruction for each mode
   • How effective address is calculated
4. 7 Marks
   bExplain the organization of a Hardwired Control Unit. Discuss its advantages, disadvantages, and applications.
   How to answer

   • Structure and organization of hardwired control unit
   • Use of fixed logic, decoders and sequence counter
   • Advantages: speed and simplicity
   • Disadvantages, inflexibility and applications
5. 7 Marks
   aExplain floating- point number representation according to IEEE standards. Discuss normalization, exponent, mantissa, and bias with examples.
   How to answer

   • IEEE 754 single and double precision format: sign, exponent, mantissa
   • Normalization concept with example
   • Biased exponent calculation
   • Example conversion of decimal to floating-point
6. 7 Marks
   bExplain the design of an Arithmetic Unit with a neat block diagram. Discuss the functions of different components.
   How to answer

   • Block diagram of arithmetic unit with registers and ALU
   • Functions of accumulator, data registers and control
   • Add, subtract and logic operations flow
   • Role of status flags
7. 7 Marks
   aExplain the flow chart and applications of Booth's Algorithm. And show the systematic multiplication process of $(-15) \times (-16)$ by using Booth's Algorithm.
   How to answer

   • Flowchart steps of Booth's algorithm
   • Rules for 00, 01, 10, 11 bit pairs with shift and add/subtract
   • Step-by-step multiplication of (-15) x (-16)
   • Applications of Booth's algorithm
8. 7 Marks
   bWhat is the Micro Program Sequencer? With block diagram, explain the working of Micro Program Sequencer.
   How to answer

   • Definition and need of microprogram sequencer
   • Block diagram with control memory and next-address logic
   • Working: sequencing, branching and mapping
   • Inputs: condition codes and control signals
9. 7 Marks
   aCalculate the page fault for a given string with the help of FIFO & Optimal page replacement algorithm, Size of frames = 4 and string 1 2 3 4 2 1 5 6 2 1 2 3 7 6 3 2 1 2 3 6.
   How to answer

   • FIFO replacement steps for given string with frame status
   • Count of page faults under FIFO
   • Optimal replacement steps using future reference
   • Count of page faults under Optimal and comparison
10. 7 Marks
    bWhat do you mean by asynchronous data transfer? Explain strobe control and hand shaking mechanism.
    How to answer

    • Definition of asynchronous data transfer
    • Strobe control method with timing
    • Handshaking mechanism: source and destination initiated
    • Comparison of strobe vs handshaking
11. 7 Marks
    aExplain the architecture and working of Magnetic Disk.
    How to answer

    • Structure of magnetic disk: platters, tracks, sectors
    • Read/write head and actuator mechanism
    • Working: rotation, seeking and data access
    • Capacity and access time factors
12. 7 Marks
    bExplain the architecture and working principle of the PCI Bus with a suitable block diagram.
    How to answer

    • Overview and features of PCI bus
    • Block diagram showing CPU, PCI controller and peripherals
    • Working principle and bus arbitration
    • Data transfer modes and advantages
13. 7 Marks
    aExplain the concept of Direct Memory Access (DMA) with a neat block diagram. Discuss the working of the DMA Controller.
    How to answer

    • Definition and need of DMA
    • Block diagram with DMA controller, CPU and memory
    • Working: bus request, transfer modes and release
    • Functions of DMA controller registers
14. 7 Marks
    bExplain the concept of virtual memory with a neat diagram.
    How to answer

    • Definition and need of virtual memory
    • Address mapping between virtual and physical memory
    • Role of page table and MMU with diagram
    • Advantages in multiprogramming
15. 7 Marks
    aExplain the concept of Inter-Processor Arbitration. Discuss different arbitration techniques used in multiprocessor systems.
    How to answer

    • Definition of inter-processor arbitration
    • Need for bus arbitration in multiprocessor systems
    • Techniques: daisy chaining, polling, independent request
    • Comparison of arbitration schemes
16. 7 Marks
    bCompare RISC and CISC architectures.
    How to answer

    • Key characteristics of RISC architecture
    • Key characteristics of CISC architecture
    • Tabular comparison on instruction set, addressing, performance
    • Examples and application areas