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Write a short note on programmed I/O. OR Discuss the programmed I/O method for controlling input-output operations.

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By Dipali Umre

Programmed I/O :

  1. Giving the Command: Imagine you’re doing homework (the CPU running a program) and you need some help from a friend (the I/O module). So, you ask your friend to do something for you.
  2. Friend’s Task: Your friend does what you asked, like finding a book for you. Once done, your friend marks it as done on a checklist (setting bits in the I/O status register).

3.No Further Interruption: Your friend doesn’t bother you again. They just wait for your next instruction.

4.No Disturbance: Your friend doesn’t scream or interrupt your work. They quietly wait for you to check on them.

5.Your Job: You, being the responsible one (the CPU), periodically check the checklist to see if your friend has finished the task. If they have, great! You move on. If not, you keep working and check back later.

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    2. Explain the functional units of digital system and their inter connections.
    3. What is a bus in digital system ? Also explain its types.
    4. Describe the architecture of bus.
    5. Discuss the bus arbitration.OR Write a short note on bus arbitration.
    6. Discuss the advantages and disadvantages of pollingand daisy chaining bus arbitration schemes.OR Explain daisy changing method. Write its advantages and disadvantages.
    7. What is memory transfer ? What are different registers associated for memory transfer ? Discuss.
    8. Explain the operation of three state bus buffers and show its use in design of common bus.
    9. Explain why the single shared bus is so widely used asan inter connection medium in both sequential and parallel computers. What are its main disadvantages ?
    10. What is the benefit of using multiple bus architecture compared to a single bus architecture ?
    11. Explain general-purpose register based organization.
    12. What is stack ? Give the organization of register stack with all necessary elements and explain the working of push and pop operations.
    13. What is a memory stack ? Explain its role in managing subroutines with the help of neat diagrams.
    14. What is the stack organization ? Compare register stackand memory stack.
    15. Explain an accumulator based central processing unit organization with block diagram.
    16. Write short note on relative addressing mode and indirect addressing mode. OR Explain the following addressing modes with the help of an example each :i. Direct ii. Register indirect iii. Implied iv. Immediate v. Indexed
    17. What is difference between implied and immediate addressing modes ? Explain with an example.
    18. Describe auto increment and auto decrement addressing modes with proper example ?
    19. How addressing mode is significant for referring memory ? List and explain different types of addressing modes.
    20. Describe sequential Arithmetic and Logic Unit (ALU)using proper diagram.
    21. Write short note on look ahead carry adders.
    22. Explain the Booth’s algorithm in depth with the help off low chart. Give an example for multiplication using Booth’s algorithm. OR Discuss the Booth’s algorithm for 2’s complement number. Also illustrate it with the some example.OR Explain Booth’s multiplication algorithm in detail.
    23. Explain Booth’s algorithm with its hardware implementation.
    24. Show step by step the multiplication process using Booth’s algorithm when (+ 15) and (– 13) numbers are multiplied.Assume 5-bit registers that hold signed numbers.
    25. Show the contents of the registers E, A, Q, SC during theprocess of multiplication of two binary numbers 11111 (multiplicand) 10101 (multiplier). The signs are not included.
    26. Show the multiplication process using Booth’s algorithm when the following numbers are multiplied : (– 13) by (+ 8).
    27. Draw the data path of 2’s compliment multiplier. Give the Robertson multiplication algorithm for 2’s compliment fractions.Also illustrate the algorithm for 2’s compliment fraction by a suitable example.
    28. Explain array multiplier method with the help of example.
    29. Write down the step for restoring and non-restoring of division operations.
    30. Draw the flow chart for restoring and non-restoring division operation.
    31. What do you mean by over flow ? Describe the over flow detection.
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    33. Perform the division process of 00001111 by 0011 (use adividend of 8 bits).
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    35. Write the steps for various floating point arithmetic operations.
    36. Explain the function of arithmetic circuit with the help of circuit diagram.
    37. Add – 35 and – 31 in binary using 8-bit registers, in signed1’s complement and signed 2’s complement.
    38. Draw the block diagram of control unit of basic computer. Explain in detail with control timing diagrams.
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    40. Explain IEEE standard for floating point numbers.OR How floating point numbers are represented in computer, also give IEEE 754 standard 32-bit floating point number format.
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    42. What is an instruction in the context of computer organization ? Explain the purpose of the various elements of an instruction with the help of a sample instruction format.
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    45. Evaluate the arithmetic statement X = (A + B)*(C + D)using a general register computer with three address, two address and one address instruction format a program to evaluate the expression.
    46. Define instruction cycle and divide instruction cycle into sub cycles with the help of diagram, explain the sequence in which sub cycles are executed.OR Explain the different cycles of an instruction execution.OR Explain all the phases of instruction cycle.
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    51. Write a short note on register transfer micro-operation.
    52. Write short note on arithmetic micro-operation.
    53. Write a short note on shift micro-operations.OR List and explain different types of shift micro-operation.
    54. Discuss the execution of a complete instruction.
    55. What is CISC ? Explain its characteristics.
    56. Discuss the advantages and disadvantages of using avariable length instruction format.
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    99. Explain I/O bus and I/O command.
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    102. How system resolve the priority of interrupt ?OR Explain polling and daisy chaining method.
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    112. Explain synchronous communication and asynchronous communication.
    113. Discuss the advantages and disadvantages of synchronous and asynchronous transmission.
    114. Describe the subroutine. Write a program which move the block of data. Write a note on subroutines.

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