Whenever ret function is called

• A) nothing happens in stack
• B) Stack is pulled
• C) Stack is cleared
• D) Stack is pushed

If a _____ stack starts at location 8, the first item pushed on it will be placed at location 8, the second element will be placed at location 7 and so on.

• A) Decrementing
• B) Incrementing
• C)
• D)

In interrupt masking, We use ________ to get control from the program without letting the program know about it.

• A) IRQ 0
• B) IRQ 1
• C) IRQ 2
• D) IRQ 3

Whenever an element is pushed on the Stack, _____ register is decremented by 2.

• A) BP
• B) CS
• C) IP
• D) SP

Which register will be on the top of the stack after execution of the following assembly code? push ax push cx push bx pull ax pull dx

• A) BX
• B) AX
• C) DX
• D) CX

How many possible I/O ports are there in the Intel architecture when using the lower 16 bits of the address bus?

• A) 256
• B) 65536
• C) 1024
• D) 512

____________ is the highest priority interrupt in interrupt controller.

• A) IRQ 2
• B) IRQ 1
• C) IRQ 3
• D) IRQ 0

Changing and restoring the state of Central Processing Unit (CPU) is referred as:

• A) Multitasking
• B) Multithreading
• C) Context Switching
• D) Thrashing

What effect does setting bit 7 in the attribute byte have on the foreground character (in the context of display memory)?

• A) Changes background color
• B) Intensity of foreground color
• C) Clears the screen
• D) Initiates blinking

How is the screen location calculated (in the context of display memory formation)?

• A) Using the MUL instruction
• B) Dividing row and column numbers
• C) Multiplying row number by 80 and adding column number
• D) Adding row and column numbers

What does the attribute byte in the word designated for one screen location hold?

• A) Cursor height information
• B) Foreground and background colors
• C) Video controller instructions
• D) ASCII code for the character

How many I/O Ports are there?

• A) 65536
• B) 65548
• C) 65520
• D) 65524

While displaying something on screen, why is ES loaded with the segment of video memory?

• A) To manipulate ASCII codes
• B) To open a window to the video memory
• C) To control cursor position
• D) To access data

What is the significance of the memory location B8000 in the context of Display Memory?

• A) BIOS vendor's problem location
• B) Physical memory location for video controller's memory
• C) Segment register for accessing video memory
• D) Default cursor position

Which of following interrupt is used for BIOS Video Services

• A) 0x21
• B) 0x13
• C) 0x16
• D) 0x10

How is the video device perceived by the computer in terms of memory?

• A) Only accessible through I/O ports
• B) Independent of system memory
• C) Linearly mapped memory
• D) Two-dimensional space with ASCII codes

Service numbers are given in ________ register while sub services in ________

• A) AX, Al or Ah
• B) Al, Ah or ax
• C) Ax, Bx
• D) AH, AL or BL

What is the purpose of sending 0x40 to the VGA card in the context of display memory formation?

• A) Change cursor position
• B) Clear the screen
• C) Set resolution
• D) Turn pixels on and off

What is the purpose of the MUL instruction in the context of display memory?

• A) Controls cursor attributes
• B) Clears the screen
• C) Multiplies ASCII codes
• D) Performs unsigned multiplication

REP with _____will utilizes the full processor power to do the scrolling in minimum time

• A) REPNE
• B) SCAS
• C) LES
• D) MOVS