36. What operation can be performed by using the instruction SUBA?

1. 1. Clear the accumulator

   
   
   

   2. Subtract A with borrow

   
   
   

   3. Subtract A

   
   
   

   4. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   Clear the accumulator Q The command subtracts the contents of register specified from the accumulator
   

   Correct Option: A

   Clear the accumulator Q The command subtracts the contents of register specified from the accumulator
   

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37. Specify the output at PORT1, after the following program has been executed—
    

    MVI	B, 82 H
    MOV	A, B
    MOV	C, A
    MVI	D, 37 H
    DUT	PORT 1
    HLT

1. 1. 82 H

   
   
   

   2. OO H

   
   
   

   3. 37 H

   
   
   

   4. FF H

   
   
   

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1. View Hint View Answer Discuss in Forum

   82 H
   ∵ Out PORT command outputs the data whatever is present in Accumulator.

   Correct Option: A

   82 H
   ∵ Out PORT command outputs the data whatever is present in Accumulator.

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38. Which of the following is commonly used to interface I/P devices?

1. 1. Latch

   
   
   

   2. Tri-state buffer

   
   
   

   3. Both (A) and (B)

   
   
   

   4. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   Tri-state buffer

   Correct Option: B

   Tri-state buffer

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39. "Short forms used for humans to give instructions to μP so it can understand those instructions" are called—

1. 1. Mnemonics

   
   
   

   2. Operands

   
   
   

   3. Machine languages

   
   
   

   4. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   Mnemonics

   Correct Option: A

   Mnemonics

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40. The register that is used to sequence the execution of the instructions is called—

1. 1. Program counter

   
   
   

   2. Stack pointer

   
   
   

   3. Accumulator

   
   
   

   4. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   Program counter function is to point to the memory address from which the next byte has to be fetched.
   

   Correct Option: A

   Program counter function is to point to the memory address from which the next byte has to be fetched.
   

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