cs401 final term current paper july 2011

[Vuhelper]

Question No: 1 ( Marks: 1 ) - Please choose one

The physical address of the stack is obtained by

► SS:SI combination



► SS:SP combination



► ES:BP combination



► ES:SP combination





Question No: 2 ( Marks: 1 ) - Please choose one

Value of AH in the write Graphics pixel service is

► 0Ch

► 0Bh

► 1Ch

► 2Ch



Question No: 3 ( Marks: 1 ) - Please choose one

Threads can have function calls, parameters and __________ variables.

► global

► local

► legal

► illegal



Question No: 4 ( Marks: 1 ) - Please choose one

Creation of threads can be

► static

► dynamic

► easy

► difficult



Question No: 5 ( Marks: 1 ) - Please choose one

How many prevalent calling conventions do exist

► 1

► 2

► 3

► 4



Question No: 6 ( Marks: 1 ) - Please choose one

VESA VBE 2.0 is a standard for

► High resolution Mode

► Low resolution Mode

► Medium resolution Mode

► Very High resolution Mode



Question No: 7 ( Marks: 1 ) - Please choose one

The serial port connection is a ------------------ connector

► 9pin DB 9

► 8pin DB 9

► 3pin DB 9

► 9pin DB 5



Question No: 8 ( Marks: 1 ) - Please choose one

Which of the following gives the more logical view of the storage medium

► BIOS

► DOS

► Both

► None



Question No: 9 ( Marks: 1 ) - Please choose one

In STOSB instruction, when DF is clear, SI is



► Incremented by 1



► Incremented by 2



► Decremented by 1



► Decremented by 2





Question No: 10 ( Marks: 1 ) - Please choose one

After the execution of STOSW the CX will be



► Decremented by 1



► Decremented by 2



► Incremented by 1



► Incremented by 2





Question No: 11 ( Marks: 1 ) - Please choose one

IRQ is referred to



► Eight input signals



► One output signal



► One input signals



► Eight output signals





Question No: 12 ( Marks: 1 ) - Please choose one

Which of the following IRQs is derived by a key board?

► IRQ 0

► IRQ 1

► IRQ 2

► IRQ 3



Question No: 13 ( Marks: 1 ) - Please choose one

Which of the following IRQs is connected to serial port COM 1?

► IRQ 4

► IRQ 5

► IRQ 6

► IRQ 7



Question No: 14 ( Marks: 1 ) - Please choose one

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

► GDTR

► IDTR

► IVT

► IDTT



Question No: 15 ( Marks: 1 ) - Please choose one

Assembly language is:

► Low-level programming language

► High-level programming language

► Also known as machine language

► Not considered closer to the computer



Question No: 16 ( Marks: 1 ) - Please choose one

The number of bits required to access 1MB of memory are

► 16 bits

► 32 bits

► Depends on the processor architecture

► 20 bits



Question No: 17 ( Marks: 1 ) - Please choose one

In STOSB instruction, SI is decremented or incremented by



► 3

► 2

► 1

► 4



Question No: 18 ( Marks: 1 ) - Please choose one

In programmable interrupt controller, which of the following ports is referred as a control port.

► 19

► 20

► 21

► 22



Question No: 19 ( Marks: 1 ) - Please choose one

INT 21 service 01H is used to read character from standard input with echo. It returns the result in ______ register.

► AL

► BL

► CL

► BH



Question No: 20 ( Marks: 1 ) - Please choose one

In device attribute word, which of the following bit decides whether it is a character device or a block device

► Bit 12

► Bit 13

► Bit 14

► Bit 15



Question No: 21 ( Marks: 1 ) - Please choose one

In 9pin DB 9, which pin number is assigned to CTS (Clear To Send) ?

► 6

► 7

► 8

► 9



Question No: 22 ( Marks: 1 ) - Please choose one

In 9pin DB 9, which pin number is assigned to RD (Received Data) ?

► 1

► 2

► 3

► 4



Question No: 23 ( Marks: 1 ) - Please choose one

VESA(Video Electronics Standards Association) organizes 16 color bits for every pixel in

► 5:5:5 format

► 5:6:5 format

► 6:5:6 format

► 5:6:7 format



Question No: 24 ( Marks: 1 ) - Please choose one

Motorola 68K processors have ....................... 23bit general purpose registers.

► 4

► 8

► 16

► 32



Question No: 25 ( Marks: 1 ) - Please choose one

Programmable Interrupt Controller (PIC) has



► One input signals and eight output signals



► One input signal and one output signal



► Eight input signals and one output signals



► Eight input signals and eight output signals





Question No: 26 ( Marks: 1 ) - Please choose one

Video services are classified into...................... broad categories.

► 5

► 4

► 3

► 2



Question No: 27 ( Marks: 2 )

What are device drivers? give your answer in two to three lines.



Question No: 28 ( Marks: 2 )

For what purpose "INT 1" is reserved ?



Question No: 29 ( Marks: 2 )

How interrupts are handled in protected mode.



Question No: 30 ( Marks: 2 )

Which bit of acknowledge is used to generate IRQ7



Question No: 31 ( Marks: 3 )

Write the name three flags which are not used for mathematical operations.



Question No: 32 ( Marks: 3 )

"INT 13 - DISK - GET DRIVE PARAMETERS " uses which registers to return error flag and error number.



Question No: 33 ( Marks: 3 )

Who is responsible for removing the parameter from the stack when we call a function in C and Pascal?





Question No: 34 ( Marks: 5 )

Read the passage carefully and choose proper word for each blank space from the list given below .



In descriptors the 32bit base is scattered into different places because of compatibility reasons. The limit is stored in 20 bits but the ...............defines that the limit is in terms of bytes of 4K pages therefore a maximum of 4GB size is possible. The ................. must be set to signal that this segment is present in memory. DPL is the descriptor privilege level again related to the protection levels in 386. .................. defines that this segment is to execute code is 16bit mode or 32bit mode. .................. is conforming bit that we will not be using. ..................signals that the segment is readable. A bit is automatically set whenever the

segment is accessed.



(A bit, C bit, G bit, D bit, P bit , R bit, B bit)



Question No: 35 ( Marks: 5 )

Write assembly language instructions to set the timer interrupt frequency at 1 ms.



Question No: 36 ( Marks: 5 )

In the context of " INT 13 - DISK - WRITE DISK SECTOR(S)" fill the blanks by choosing the correct answer against each blank space from the list given at the bottom.



AH = ....................

AL = ...............................

CH = ..............................

CL = sector number 1-63 (bits 0-5)

high two bits of cylinder (bits 6-7, hard disk only)

DH = .....................................

DL = drive number (bit 7 set for hard disk)

ES:BX -> .......................................


(Number of sectors to write, head number , 03h, data buffer , low eight bits of cylinder number)