The address bus of the 8085 microprocessor is of ____ bits.

 

1. The 8085 microprocessor has how many bits in its data bus?

A. 4-bit
B. 8-bit
C. 16-bit
D. 32-bit
Answer: B. 8-bit
Explanation:
The 8085 microprocessor is an 8-bit microprocessor, meaning it can process 8 bits of data at a time.

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2. The address bus of the 8085 microprocessor is of ____ bits.

A. 8
B. 12
C. 16
D. 20
Answer: C. 16
Explanation:
8085 has a 16-bit address bus, which allows it to address up to $2^{16} = 65,536$ memory locations (64 KB).

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3. The 8085 microprocessor is manufactured using which technology?

A. TTL
B. CMOS
C. NMOS
D. PMOS
Answer: C. NMOS
Explanation:
8085 is fabricated using NMOS technology which provides high speed compared to PMOS.

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4. The clock frequency of 8085 microprocessor is typically ____ MHz.

A. 1
B. 2
C. 3
D. 5
Answer: D. 5
Explanation:
8085 microprocessor typically operates at 3 MHz or 5 MHz clock frequency depending on the version.

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5. Which of the following is a 16-bit register in 8085?

A. Accumulator
B. Stack Pointer
C. B register
D. Flag register
Answer: B. Stack Pointer
Explanation:
Stack Pointer (SP) is a 16-bit register that holds the address of the top of the stack.

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6. The instruction “MOV A, B” copies the contents of:

A. A to B
B. B to A
C. B to C
D. A to memory
Answer: B. B to A
Explanation:
MOV A, B copies data from register B into accumulator A.

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7. The number of address lines in 8085 is:

A. 8
B. 12
C. 16
D. 20
Answer: C. 16
Explanation:
8085 can address 64 KB of memory (16 address lines).

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8. The accumulator in 8085 is used for:

A. Holding the instructions
B. Temporary data storage and arithmetic operations
C. Address generation
D. Stack operations
Answer: B. Temporary data storage and arithmetic operations
Explanation:
The accumulator (register A) stores data and results of arithmetic and logic operations.

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9. The instruction “IN 80H” means:

A. Input data from port 80H to accumulator
B. Output data from accumulator to port 80H
C. Increment accumulator by 80H
D. None
Answer: A. Input data from port 80H to accumulator
Explanation:
“IN” instruction reads data from the specified port into the accumulator.

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10. Which flag is set when an arithmetic carry is generated out of the D3 bit?

A. Carry flag
B. Auxiliary carry flag
C. Zero flag
D. Sign flag
Answer: B. Auxiliary carry flag
Explanation:
The Auxiliary Carry (AC) flag is set when a carry is generated from bit D3 to D4 in arithmetic operations.