PreCAT – Section C - Microprocessor
Sequential Circuits
Question 1: Which of the following 8 bit registers are grouped together to form 16 bit registers?
A. B and C
B. B and D
C. A and B
D. None of the above
Question 2: Which of the following flag is not present in 8085?
A. Carry
B. Zero
C. Parity
D. Trap
Question 3: In 8085 microprocessor, data-bus and address bus are multiplexed in order to
A. Increase the speed of microprocessor.
B. Reduce the number of pins.
C. Connect more peripheral chips.
D. None of the above
Question 4: ALU (Arithmetic and Logic Unit ) of 8085 microprocessor consists of
A. Accumulator, temporary register, arithmetic and logic circuits
B. Accumulator, arithmetic, logic circuits and five flags
C. Accumulator, arithmetic and logic circuits
D. Accumulator, temporary register, arithmetic, logic circuits and five flags
Question 5: Which of the following statements for Intel 8085 is correct?
A. Program Counter (PC) specifies the address of the instruction last executed
B. PC specifies the address of the instruction being executed
C. PC specifies the address of the next instruction to be executed
D. PC specifies the number of instructions executed so far
Question 6: In which of the following data and address cannot be fetched simultaneously?
A. Harvard
B. Von neumann
C. Both
D. None
Question 7: In RISC instruction size is variable?
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PreCAT – Section C - Microprocessor
A. True
B. False
Question 8:
8085:: Address Bus : _____:: Data Bus : ______
A. 16, 16
B. 8, 16
C. 16,8
D. None of the above
Question 9: Which of the following interrupt is not present in 8085?
A. RST 7.5
B. INTA
C. TRAP
D. None of the above
Question 10: Which of the following is non maskable interrupt?
A. INTR
B. RST 6.5
C. TRAP
D. RST 7.5
Question 11: Causing a flag to became 0 is called:
A. Clearing a flag
B. Case a flag
C. Both a and b
D. None of these
Question 12: In which register instruction is decoded prepared and ultimately executed:
A. Instruction register
B. Current register
C. Both a and b
D. None of these
Question 13: Single address computer instruction has two parts:
A. The operation code
B. The operand
C. A and B
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PreCAT – Section C - Microprocessor
D. None of these
Question 14: Stack works on:
A. LILO
B. LIFO
C. FIFO
D. None of these
Question 15: The CPU yields control of the bus to the DMA controller via:
A. DMA acknowledge signal
B. DMA integrated signal
C. DMA implicitly signal
D. None of these
Question 16: The point where control returns after a subprogram is completed is known as the :
A. Return address
B. Main Address
C. Program Address
D. Current Address
Question 17: The processor 80386/80486 and the Pentium processor uses _____ bits address
bus:
A. 16
B. 32
C. 36
D. 64
Question 18: The processor uses the stack to keep track of where the items are stored on it this
by using the:
A. Stack pointer register
B. Queue pointer register
C. Both a & b
D. None of these
Question 19: The subprogram finish the return instruction recovers the return address from
the:
A. Queue
B. Stack
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PreCAT – Section C - Microprocessor
C. Program counter
D. Pointer
Question 20: Which bus carry addresses:
A. System bus
B. Address bus
C. Control bus
D. Data bus
Question 21: _____ subsystem that transfers data between computer components inside a
computer or between computers:
A. Chip
B. Register
C. Processor
D. Bus
Question 22: _________ Stores the instruction currently being executed:
A. Instruction register
B. Current register
C. Both a and b
D. None of these
Question 23: In 8085, multiplication is done by
A. MLI B
B. MUL B
C. Both A and B
D. None of the above
Question 24: Accumulator contains 4DH, what will be the value of flags after executing
following instruction
ADI 59H
A. Ac = 0, P = 1, C = 0
B. Ac = 1, P = 0, C = 0
C. Ac = 1, P = 0, C = 1
D. None of the above
Sunbeam Institute of Information Technology, Pune
PreCAT – Section C - Microprocessor
Question 25: What will be the value of accumulator after executing following command?
SBI 37H borrow = 1, A=37H
A. -1
B. FFH
C. 0377
D. All of the above
E. None of the above
Question 26: What will be the value of accumulator after executing following instructions
MVI A, 49H
MVI C, 12H
ORA C
A. 5BH
B. 5AH
C. 4AH
D. 4BH
Question 27: Bus interface unit is not responsible for
A. sends address of the memory or IO
B. supports instruction queuing
C. supports arithmetic operations
D. provides address relocation facility
Question 28: Find the status of CF, SF, and AF after the following instructions are executed.
MOV AL, 35 H
ADD AL, 0CE H
A. CF = 0, SF = 1, AF = 1
B. CF = 1, SF = 1, AF = 1
C. CF = 1, SF = 0, AF = 1
D. CF = 1, SF = 0, AF = 0
Question 29: Assume that CS register=3000 H and IP =2000 H. To fetch an instruction form
the memory, find the memory address from which the next instruction will be fetched.
A. 3200H
B. 32000H
C. 3200
D.32000
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PreCAT – Section C - Microprocessor
Question 30: Assume that, SS=3000 H, BP=0010 H, SI=0040 H Find the physical address in
following instruction.
MOV AL, [BP+SI]
A. 30050H
B. 30040H
C. 30010H
D. None of the above
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