CS401- Computer Architecture and Assembly Language Programming McQs collection Part2

CS401- Computer Architecture and Assembly Language Programming  McQs collection

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

To transfer control back the RET instruction take

• 1 argument

• 1 argument

• 3 arguments

• No arguments

Question No: 2                                 ( M a r k s: 1 )

In STOSB instruction SI is decremented or incremented by

4

1
2 
3

Question No: 3                                 ( M a r k s: 1 )\

CMPS instruction subtracts the source location to the destination location.
Destination location always lies in

DS:SI

DS:DI

ES:SI

ES:DI

Question No: 4 ( M a r k s: 1 )

Regarding assembler, which statement is true:

Assembler converts mnemonics to the corresponding OPCODE

Assembler converts OPCODE to the corresponding mnemonics.

Assembler executes the assembly code all at once
Assembler executes the assembly code step by step

Question No: 5                                 ( M a r k s: 1 ) \

Iof “BB” is the OPCODE of the instruction which states to “move a constant value to AX register”, the hexadecimal representation (Using little Endian notation) of the instruction “Mov AX,336” (“150” in hexadecimal number system) will be:

0xBB0150

0x5001BB
0x01BB50

0xBB5001

Question No: 6                                 ( M a r k s: 1 )

In the instruction  MOV AX, 5 the number of operands are

1

2

3

4

Question No: 7                                 ( M a r k s: 1 )

The maximum parameters a subroutine can receive (with the help of registers) are

6

7
8
9

Question No: 8                                 ( M a r k s: 1 )

In assembly the CX register is used normally as a ______________register.

source

counter

index

pointer

Question No: 9                                 ( M a r k s: 1

All the addressing mechanisms in iAPX 8 8 return a number called _ _ _ _ _ _ _ _ _ _ _ _ _address .

effective

faulty

indirect

direct

Question No: 10                                 ( M a r k s: 1 ) \

When a 16 bit number is divided by an 8 bit number, the dividend will be in

AX

BX

CX

DX

Question No: 11                                 ( M a r k s: 1 )

in Left-Shift-Operation the left most bit _______

will drop

will go into CF

Will come to the right most

will be always 1

Question No: 12                                 ( M a r k s: 1 )

Suppose the decimal number "35" after shifting its binary two bits to left, the newvalue becomes _________

35

70

140
17

Question No: 13                                 ( M a r k s: 1 )

When divide overflow occurs processor will be interrupted this type of interrupt is called

Hardware interrupt

Software interrupt

Processor exception

Logical interrupts

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

Which mathematical operation is dominant during the execution of SCAS instruction

Division

Multiplication

Addition

Subtraction

Question No: 15                                 ( M a r k s: 1 )

After the execution of REP instruction CX will be decremented then which of the

following flags will be affected?

CF

OF
DF

No flags will be affected

Question No: 16                                 ( M a r k s: 1 )

_________ is one of the reasons due to which string instructions are used in 8088

Efficiency and accuracy

Reduction in code size and accuracy

Reduction in code size and speed

Reduction in code size and efficiency

Question No: 17                                 ( M a r k s: 1 )

Write any two control instructions.

Question No: 18                                 ( M a r k s: 1 )

RET instruction take how many arguments

Question No: 19                                 ( M a r k s: 2 )

Explain the fuction of rotate right (ROR) instruction

Question No: 20                                 ( M a r k s: 2 )

Describe the PUSH function

Question No: 21                                 ( M a r k s: 3 )

Write down the names of four segment registers?

Question No: 22                                 ( M a r k s: 3 )

For what purpose "INT 4" is reserved?

Question No: 23                                 ( M a r k s: 5 )

Given that [BX+0x0100]          BX=0x0100

Ds=0xFFF0

Calculate the physical address

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

 The physical address of the stack is obtained by

► SS:SP combination

► SS:SI combination

► SS:SP combination

► ES:BP combination

► ES:SP combination

Question No: 2    ( M a r k s: 1 )    

 After the execution of instruction “RET ”

       ► SP is incremented by 2

       ► SP is incremented by 2

► SP is decremented by 2

► SP is incremented by 1

► SP is decremented by 1

Question No: 3    ( M a r k s: 1 )    

 The second byte in the word designated for one screen location holds

       ► Character color on the screen

► The dimensions of the screen

► Character position on the screen

       ► Character color on the screen

► ASCII code of the character

Question No: 4    ( M a r k s: 1 )    

 REP will always

► Decrement CX by 1

► Increment CX by 1

► Increment CX by 2

► Decrement CX by 1

► Decrement CX by 2

Question No: 5    ( M a r k s: 1 )    

 The basic function of SCAS instruction is to

► Compare

► Compare

► Scan

► Sort

► Move data

Question No: 6    ( M a r k s: 1 )   

 Index registers are used to store __________

►Address

►Data

►Intermediate result

►Address

►Both data and addresses

Question No: 7    ( M a r k s: 1 )    

 The bits of the _____________ work independently and individually

►flags register

►index register

►base register

►flags register

►accumulator

Question No: 8    ( M a r k s: 1 )    

 To convert any digit to its ASCII representation

► Add 0x30 in the digit

► Add 0x30 in the digit

► Subtract 0x30 from the digit

► Add 0x61 in the digit

► Subtract 0x61 from the digit

Question No: 9    ( M a r k s: 1 )    

 When a 32 bit number is divided by a 16 bit number, the quotient is of

       ► 4 bits   

► 32 bits

► 16 bits

► 8 bits

       ► 4 bits   

Question No: 10    ( M a r k s: 1 )    

 When a 16 bit number is divided by an 8 bit number, the quotient will be in

► AL

► AX

► AL

► AH

► DX

Question No: 11    ( M a r k s: 1 )   

 Which mathematical operation is dominant during the execution of SCAS instruction

       ► Division

       ► Division

► Multiplication

► Addition

► Subtraction

Question No: 12    ( M a r k s: 1 )    

 If AX contains decimal -2 and BX contains decimal 2 then after the execution of instructions:

CMP  AX, BX

JA label

       ► Zero flag will set

► Jump will be taken

       ► Zero flag will set

► ZF will contain value -4

► Jump will not be taken

Question No: 13    ( M a r k s: 1 )    

 The execution of the instruction “mov word [ES : 160],  0x1230” will print a character “0” on the screen at

► First column of second row

► Second column of first row

► First column of second row

► Second column of second row

► First column of third row

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

 If the direction of the processing of a string is from higher addresses towards lower addresses then

► DF is cleared

► ZF is cleared

► DF is cleared

► ZF is set

► DF is set

Question No: 15    ( M a r k s: 1 )    

 The instruction ADC has________   Operand(s)

       ► 3

► 0

► 1

► 2

       ► 3

Question No: 16    ( M a r k s: 1 )  

 Which bit of the attributes byte represents the red component of background color ?

       ► 3

       ► 3

► 4

► 5

► 6

Question No: 17    ( M a r k s: 2 )

 What is difference between SHR and SAR instructions?

SHR

The SHR inserts a zero from the left and moves every bit one position to the right and copy the rightmost bit in the carry flag.

SAR

The SAR shift every bit one place to the right with a copy of the most significant bit left at the most significant place. The bit dropped from the right is caught in the carry basket. The sign bit is retained in this operation.

Question No: 18    ( M a r k s: 2 )

 For what purpose "INT 1" is reserved ?

Question No: 19    ( M a r k s: 2 )

 Define implied operand?

It is always in a particular register say the accumulator. It needs to not be mentioned in the instruction.

Q=1:
Which bit of attributes byte represents the blue component of foreground color?

• 0
• 1
• 2
• 3

Q=2:
The clear screen operation initializes the whole block of video memory to:

• 0417
• 0714
• 0741
• 017

Q=3:
When the operand of DIV instruction is of 16 bit then implied dividend will be of

• 64-bit
• 32-bits
• 16-bits
• 8--bits

Q=4
Which of the following is the pair of register used to access memory instring instruction:

• DI and BP
• SI and  BP
• DI and SI
• DS and Si

Q=5
A fat32 file system directory entry in DOS consist of how many bytes?

• 16
• 24
• 32
• 64

Q=6:
Which register is generally used to specify the services number of an interrupt?

DX
AX
BX

CX
………………………………………………………………………………………….
Q=7:
In 9 pin db  9 connector ,which pin is assigned to RD(received data)

• 1
• 2
• 3
• 4

Q=8
In case of COM file, maximum length of parameters passed through command line can be……….

• 63 bytes
• 127bytes
• 255 bytes
• 511 bytes

Q=9
We can access the DOS service using;

• Int 0x21
• Int 0x13
• Int 0x 10
• Int 0x 08

Q=10
In 9 pin 9 connector,which pin is assigned to signal ground

• 3
• 4
• 5
• 6

Q=11:
BPB stands for

• Basic parameter block
• Bios precise block
• Basic precise block
• Bios parameter block

Q=12
Int 13-bios disk service “generally uses which register to return the error flag?

• CF
• DL
• AH
• AL

Q=13:
The first sector on the hard disk contains the

• Hard disk size
• Partition table
• Data size
• Sector size

Q=14
Operating system organize data in the form of

• Folder
• Batch file
• File
• None of above

………



Q=15
In 9 pin db 9 connector, which pin is assigned to TD(transmitted data)

• 1
• 2
• 3
• 4

Q=16”
Device derive can be divided into ----------major categories.

• 5
• 4
• 3
• 2

1. BL contains 5 decimal then after right shift , BL will become

• 3
• 2.5
• 5
• 10

2. 8 * 16 font is stored in ________ bytes.

• 3
• 4
• 8
• 16

3. In DOS input buffer , number of characters actually read on return is stored in

• First byte
• Second byte
• Third byte
• Fourth byte

4. IRQ 0 has priority

• Low
• High
• Highest
• Medium

5. Thread registration code initialize PCB and add to linked list so that _____ will give it turn.

• Assembler
• Linker
• Scheduler
• Debugger

6. Traditional calling conventions are in ______ number

• 1
•  2
• 3
• 4

7. VESA VEB 2.0 is standard for

• High Resolution Mode
• Low Resolution Mode
• Very High Resolution Mode
• Medium Resolution Mode

8. To clear direction flag which instruction is used

• Cld
• Clrd
• Cl df
• Clr df

9. In STOSW instruction , When DI is cleared , SI is

• Incremented by 1
•  Incremented by 2
• Decremented by 1
• Decremented by 2

10. Interrupt that is used in debugging with help of trap flag is

• INT 0
• INT 1
• INT 2
• INT 3

11. INT for arithmetic overflow is

• INT 1
• INT 2
• INT 3
• INT 4

12. IRQ referred as

• Eight Input signals
• One Input signal
• Eight Output signals
• One output signal

13. IRQ for keyboard is ____1_____

14. IRQ for sound card is ______5_______

15. IRQ for floppy disk is ______6_______

16. IRQ with highest priority is

• Keyboard IRQ
•  Timer IRQ
• Sound Card
• Floppy Disk

17. Pin for parallel port ground is

• 10-18
•  18-25
• 25-32
• 32-39

18. The physical address of Interrupt Descriptor Table (IDT) is stored in

• GDTR
• IDTR
• IVT
• IDTT

19. Execution of “RET 2” results in?

20. CX register is

•  Count register
• Data register
• Index register
• Base register

21. OUT instruction uses __AX_____ as source register.

22. IN DB-9 connector the Data Set ready pin is at

• 5
• 6
• 7
• 8

23. If two devices uses same IRQ then there is

• IRQ collision
• IRQ conflict
• IRQ drop

24. VESA organizes 16 bit color for every pixel in ratio

• 5:5:5
•  5:6:5
• 6:5:6
• 5:6:7

25. Division by zero is done by which interrupt.

Interrupt 0.