The 8086 is a _____-bit microprocessor.

• 8

• 16

• 32

• 64

The Bus Interface Unit (BIU) is responsible for:

• Arithmetic and logic operations

• Memory and I/O interfacing

• Instruction execution

• All of the above

Which register holds the address of the next instruction?

• SP

• IP

• AX

• DS

In which addressing mode is the operand specified directly in the instruction?

• Register

• Direct

• Immediate

• Indirect

[BX] is an example of which addressing mode?

• Direct

• Register

• Indexed

• Register Indirect

The instruction MOV AX, [BX] copies data from:

• AX to BX

• Memory to AX

• BX to AX

• AX to memory

The directive used to define a byte in assembly is:

• DB

• DW

• DD

• DC

The number of I/O ports provided by 8255 is:

• 2

• 3

• 4

• 5

In 8255, the control word 82H configures which port as output?

• Port A

• Port B

• Port C

• All ports

The 8251 USART is used for:

• Parallel I/O

• Serial communication

• Timing operations

• Interrupt handling