VU MIDTERM EXAMINATION Spring 2010 CS401- Computer Architecture and Assembly Language Programming

VU  MIDTERM EXAMINATION   Spring 2010 CS401- Computer Architecture and Assembly Language Programming (Session - 3)

Time: 60 min
M a r k s: 38
Question No: 1 ( M a r k s: 1 )
After the execution of SAR instruction

► The msb is replaced by a 0

► The msb is replaced by 1

► The msb retains its original value

► The msb is replaced by the value of CF

Question No: 2 ( M a r k s: 1 )
RETF will pop the offset in the
► BP
► IP
► SP
► SI

Question No: 3 ( M a r k s: 1 )
The routine that executes in response to an INT instruction is called

► ISR

► IRS

► ISP

► IRT

Question No: 4 ( M a r k s: 1 )
The first instruction of “COM” file must be at offset:
► 0x0010
► 0x0100
► 0x1000
► 0x0000

Question No: 5 ( M a r k s: 1 )
“Far” jump is not position relative but is _______________
► memory dependent
► Absolute
► temporary
► indirect

Question No: 6 ( M a r k s: 1 )
Only ___________ instructions allow moving data from memory to memory.

► string
► word
► indirect
► stack

Question No: 7 ( M a r k s: 1 )
After the execution of instruction “RET 2”

► SP is incremented by 2
► SP is decremented by 2
► SP is incremented by 4
► SP is decremented by 4
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Question No: 8 ( M a r k s: 1 )
DIV instruction has

► Two forms
► Three forms
► Four forms
► Five forms

Question No: 9 ( M a r k s: 1 )
When the operand of DIV instruction is of 16 bits then implied dividend will be of

► 8 bits
► 16 bits
► 32 bits
► 64 bits

Question No: 10 ( M a r k s: 1 )
After the execution of MOVS instruction which of the following registers are updated
► SI only

► DI only

► SI and DI only

► SI, DI and BP only

Question No: 11 ( M a r k s: 1 )
In 8088 architecture, whenever an element is pushed on the stack
► SP is decremented by 1
► SP is decremented by 2
► SP is decremented by 3
► SP is decremented by 4

Question No: 12 ( M a r k s: 1 )
When a very large number is divided by very small number so that the quotient is larger than the space provided, this is called

► Divide logical error
► Divide overflow error
► Divide syntax error
► An illegal instruction

Question No: 13 ( M a r k s: 1 )
In the word designated for one screen location, the higher address contains

► The character code
► The attribute byte
► The parameters
► The dimensions

Question No: 14 ( M a r k s: 1 )

Which of the following options contain the set of instructions to open a window to the video memory?
► mov AX, 0xb008
mov ES, AX
► mov AX, 0xb800
mov ES, AX
► mov AX, 0x8b00
mov ES, AX
► mov AX, 0x800b
mov ES, AX

Question No: 15 ( M a r k s: 1 )
In a video memory, each screen location corresponds to
► One byte
► Two bytes
► Four bytes
► Eight bytes

Question No: 16 ( M a r k s: 1 ) \The execution of the instruction “mov word [ES : 0], 0x0741” will print character “A” on screen , background color of the screen will be

► Black
► White
► Red
► Blue

Question No: 17 ( M a r k s: 2 )
Why is it necessary to provide the segment and offset address in case of FAR jump ?

Question No: 18 ( M a r k s: 2 )
What’s your understanding about Incrementing and Decrementing Stack?

Question No: 19 ( M a r k s: 2 )
Number2:
IF DF=0 what its represent and IF DF=1 what its represent ?

Question No: 20 ( M a r k s: 3 )
What is the Difference between CALL and RET

Question No: 21 ( M a r k s: 3 )
Tell the Formula to scroll up the screen

Question No: 22 ( M a r k s: 5 )
Explain how extended shifting is performed

Question No: 23 ( M a r k s: 5 )
Write a subroutine to calculate the string length.?