MPMC 2024-25 ISE-I

 What is true about Program counter in a real-world scenario?

• It stores the result of arithmetic and logic operations

• It determines the output of the program

• It is used to store user input

• It indicates the address of the next instruction to be executed.

For a computer science student, the following program is executed :

MVI A, 05 H

MVI B, 05 H

PTR: ADD B

DCR B

JNZ PTR

ADI 03 H

HLT

At the end of the program, accumulator contains

• 2EH

• 17H

• 23H

• 20H

The contents of register (B) and accumulator (A) of a computer system are 3C H and 89 H respectively. The contents of A and the status of carry flag (CY) and sign flag (S) after executing a subtraction operation are

• The contents of A is 3C H, CY is 0, and S is 0

• The contents of A is 00 H, CY is 1, and S is 1

• The contents of A is 4D H, CY is 1, and S is 1

• The contents of A is 89 H, CY is 0, and S is 0

What is the status of the accumulator of 8085 microprocessor after the completion of the 'XRI F0 H' instruction?

• Clear the lower four bits of the accumulator in 8085.

• Complement the upper four bits of the accumulator in 8085

• Clear the upper four bits of the accumulator in 8085

• Complement the lower four bits of the accumulator in 8085.

What is the purpose of the JNZ instruction in 8085 microprocessor?

• To jump to a specific memory location if the zero flag is set

• To jump to a specific memory location if the zero flag is not set

• To jump to a specific memory location if the carry flag is set

• To jump to a specific memory location if the carry flag is not set

How does the 8085 microprocessor handle interrupts in a real-world scenario?

• It ignores all interruptions during a critical operation

• It prioritizes emergency alerts over routine notifications

• It saves the current progress and status before attending to an urgent task

• It directly responds to an urgent request without any delay

What is the significance of the HLT instruction in 8085 microprocessor programming?

• It halts the microprocessor until the next interrupt occurs

• It stops the execution of the program and puts the microprocessor in a halt state

• It resets all the registers and flags of the microprocessor

• It clears the memory and restarts the program from the beginning

Explain the purpose of the XTHL instruction in 8085 microprocessor programming.

• It exchanges the contents of the H and L registers with the contents of the stack pointer

• It exchanges the contents of the accumulator with the contents of the H and L registers

• It exchanges the contents of the accumulator with the contents of the stack pointer

• It exchanges the contents of the H and L registers with the contents of the memory location pointed by the stack pointer

How does the 8085 microprocessor handle the JMP instruction in a real-world scenario?

• It saves the return address on the stack and jumps to a specific memory location

• It directly jumps to a specific memory location without saving the return address

• It ignores the JMP instruction during program execution

• It clears the stack before executing the JMP instruction

Which of the following is true about Control and status signals?

• There are 3 control signal and 3 status signals.

• These signals are used to identify the nature of operation.

• Three status signals are IO/M, S0 & S1

• All of the above