Let's assume that location A in memory has 0000 bits. What will be the result when XOR operation is performed between A and A (A XOR A)?

• A) 1
• B) 0
• C) 11
• D) 10

Which of following pins of parallel port are used to carry the data from processor to the device connected through parallel port?

• A) pin 2 to pin 9
• B) pin 10
• C) pin 4
• D) pin 18 to pin 25

The default source location for both LODS and MOVS instruction is ______.

• A) BP:ES
• B) CS:IP
• C) DS:SI
• D) AX:SI

Using OUT instruction on data port (378), 1 bits result in a ___________ signal on the corresponding pin.

• A) 10V
• B) 1V
• C) 5V
• D) 3V

To return back from the Interrupt Service Routine to position from where ISR was called, which of the following instruction is used?

• A) retf
• B) iret
• C) retn
• D) ret

Which of following IO port is used to send an EOI signal to PIC?

• A) 0x23
• B) 0x20
• C) 0x21
• D) 0x22

Which assembly language instruction is used to enable the interrupt requests?

• A) sti
• B) cli
• C) dit
• D) eit

Every String Instruction in iAPX88 architecture has ____ variants.

• A) 8
• B) 2
• C) 4
• D) 16

If ________ is set, then after every instruction a type 1 interrupt will automatically be generated.

• A) Overflow flag
• B) Trap flag
• C) Parity flag
• D) Carry flag

mov ax,2 push ax pop bx add bx,ax at the end of execution of above code, what will be value in ax?

• A) 1
• B) 0
• C) 4
• D) 2

In iAPX88 architecture, the DOS Interrupt Vector Table resides at _____ memory location.

• A) 8
• B) 4
• C) 2
• D) 0

Which IO port is used to scan the code of key pressed on the keyboard?

• A) 0x62
• B) 0x60
• C) 0x61
• D) 0x63

When ret function is called SP is ______ by _____

• A) Decremented, 2
• B) Incremented, 1
• C) Incremented, 2
• D) Deceremented 1

What is the purpose of ports 20 and 21 in the Programmable Interrupt Controller (PIC)?

• A) Port 20 is for keyboard input, and port 21 is for mouse input.
• B) Port 20 is the interrupt mask register, and port 21 is the control port.
• C) Port 20 is for sound card communication, and port 21 is for network card communication.
• D) Port 20 and port 21 both serve as control ports for the PIC.

Stack behaves as

• A) First in Last out
• B) First in First Out
• C) Last In First Out
• D) Last in Last out

IRET returns on the basis of ________ and __________.

• A) CS, SS
• B) CS, IP
• C) DS, IP
• D) IP, SP

SP register points to_______.

• A) Bottom of stack
• B) Top of stack
• C) Highest limit of stack
• D) Current item of stack

The_______ bit tells that this is a system descriptor while the 1110 following it tells that it is a 386 interrupt gate.

• A) O
• B) S
• C) T
• D) P

Each entry of the interrupt vector table is of __________ bytes.

• A) 2
• B) 1
• C) 3
• D) 4

__________ interrupt is used for Arithmetic overflow.

• A) INT 4
• B) INT 7
• C) INT 8
• D) INT 6