CS401 Solved Grand Quiz Spring 2021
Welcome to CS401 Grand Quizzes at VUExamGuide.com – your ultimate destination for 100% Correct Answers! If you are a CS401 student at VU, seeking a reliable study resource to excel in your quizzes and exams, you’ve come to the right place.
Our CS401 Grand Quizzes cover a diverse range of topics, meticulously prepared by our expert team to ensure accuracy and clarity. With a focus on computer architecture and assembly language programming, these quizzes will deepen your understanding and enhance your problem-solving skills in low-level programming.
No more grappling with complex instructions or uncertain solutions! VUExamGuide.com empowers you to excel in CS401. Embrace the knowledge and skills you need to master computer architecture and become proficient in assembly language programming.
Join us now and embark on a journey of academic excellence with CS401 Grand Quizzes. Prepare to shine and propel yourself towards a brighter future – start exploring VUExamGuide.com today!
CS401 Solved MCQs
mov [1234], ax is an example of ________________ addressing.
Direct
____jump is absolute and not position relative.
FAR
In Extended Multiplication, we store the Multiplication in _____ bits , and the result is stored in _____ bits
16 , 32
SHL and SAL are same
True
Simple CMP instruction uses _____operation
Subtraction
The jump is taken if the last arithmetic operation changed the sign unexpectedly.
JO
The Execution of the instruction “mov word [ES:160]”willm print a character on the screen at the_____
First, second
The segment off set pair is called a/an__________address.
Logical
If AX=00FF, then which of the following instruction can be used to change the value of AX to FF00
AND AX,FF00
Total NUMBER of reserved interrupts un the intel 8088 are_____
8
A/An ____ is an area of memory that holds all local variables and parameters.
Stack
____________is used for temporary diversion.
CALL
The swap flag can be stored in _____________
A Register
The JUMP is taken if the last arithmetic has produced a positive number in its destination
JNP
OUR computer screen is like a 2-D array having _____ rows and ______ columns.
25, 40
The correlation process from the interrupt a number to the interrupt handler uses a table is called.
Interrupt Vector table
The 8088 processor divides interrupts into_____classes.
Two
__________function decrements SP ( the STACK pointer) by, Two, and then transfer a word from the source operand to the top of the stack now pointed to by SP.
PUSH
REPE repeats a string instruction while the _________
ZERO
Which of the following is the extension of object file?
.exe
Code size reduction and improvement in speed were the two reasons for introducing block processing instruction in the _____ processor.
8088
REP allows the instruction to be repeated__times.
CX
EACH bit of the ______ register conveys a different meaning.
FLAGS
Scrolling is the process of the moving one or more lines towards this top or bottom of the screen, a and the new line that appears on the top or bottom is____
cleared
The most convenient place to store local variables is ______
Stack
When SI or DI are used, we name the method ____ addressing.
indexed
A value 0500 is stored in my memory. If we transfer this value to a general-Purpose register. Then it will be shown as
0500
In iAPX88, when an element is poped from the stack .SP is ______by 2
DECREMENTED
Which of the following is used to clear the direction flag?
cld
In __________________ operation, a zero is inserted from the left and every bit moves one position to the right. The right most bit is dropped into the carry flag.
shift logical right operation
iAPX88 consist of______register
14
Also observe that with the CALL instruction ___is decremented by two from FFFE to FFFC, and the stack windows shows 0150 at its top.
SP
For example the clear screen operation initializes this whole block to
0/0720.
Software interrupts on the contrary are not generated from outside the processor. They just provide an extended call mechanism. Far call allows us to jump anywhere in the whole megabyte of memory.
Far
The ____and DPL have the same meaning as in data and code descriptors.
P
The maximum parameters a subroutine can receive are _____when all the general registers are used.
Seven
In general the memory cell cannot be wider than the width of the
data bus.
BP the default segment used is
SS.
IN 8051 by the same manufacturer has an______ stack
Incrementing
Mov [1234] ax is an example of —- addressing.
Direct
The important thing to observe in the ASCII table is the contiguous arrangement of the uppercase alphabets (41-5A), the lowercase alphabets (61-7A), and the numbers
(30-39).
How many are the functions of a register.
Two
B80500, B8 was the opcode and
0500
In the opcode B80500, B8 was the opcode and 0500 was the operand stored immediately
afterwards
Scrolling is the process when all the lines on the screen move one or more lines towards the top of towards the bottom and the new line that appears on the top or the bottom is
cleared.
This precise synchronization between the processor and the memory is the responsibility of the
control bus.
In the _________the carry flag is inserted from the left, every bit moves one position to the right, and the right most bit is dropped in the carry flag
rotate through carry right instruction(RCR),
the interrupt call loads new values in CS, IP, and
FLAGS.
SCAS compares a source byte or word in register AL or AX with the _______string element addressed by ES:DI and updates the flags.
Destination
How logical errors are different from syntax error _____ is generally used in a loop instead the REP.
Identifying syntax and logical errors is responsibility of assembler and programmer respectively
LODS
The instructions for permanent diversion in intel 8088 is
jmp
In _______a zero is inserted from the right, and every bit moves one position to its left , the most significant bit drops into the carry flag.
______subtracts one from its single operand.
DEC
Which of the following formulaes calculates the desired location on the screen?
location = ( hypos * 80 + epos ) * 2
Stack is a data structure that behaves in a first in last _____manner.
Out
8088 is a_________ processor with its accumulator and all registers of
16 bits
REPE or REPNE are used with the _______instructions.
SCAS
____________can be used to check whether particular bits of a number are set or not.
AND
Which of the following flags sets when a larger number is subtracted from a smaller number?
0F
When an element is pushed on the stack, SP is decremented by _______
2
Which of the following operations is used to clear any specific bit in a binary number?
AND
“mov [bx], ax” moves the two byte contents of the AX register to the address contained in the BX register in the current
data segment.
OR operation in assembly
“or ax, bx”
AX and BX. There are _____ AND operations as a result; one for every bit of AX
16
operand of POP is called _______since data is moving from the stack to the operand.
Destination
8088 is a _____ bit processor with its accumulator and all registers of
16
Whenever an element is pushed on the stack SP is decremented by
Two
The______ has a special role in debugging
trap flag
The convention to return a value from a subroutine is to use
the AX register
The iAPX88 architecture consists
of 14 registers..
the CALL instruction _____is decremented by two
SP
The P and DPL have the same meaning as in data and code descriptors.
. The maximum parameters a subroutine can receive are ____when all the general registers are used.
Seven
memory cell cannot be wider than the width of
the data bus.
BP is attached to SS by default
In 8051, there is an _____stack
Incrementing
in the ASCII table is the contiguous arrangement of the uppercase alphabets (41-5A), the lowercase alphabets (61-7A), and the numbers
(30-39).
multiply two 32bit numbers and store the answer in a 64bit location.
In the opcode B80500, B8 was the opcode and 0500 was the operand stored immediately afterwards
0500
The first instruction of “COM” file must be at offset
- 0x0010
- 0x0100
- 0x1000
- 0x0000
The iAP888 architecture consists of ___________ register.
- 12
- 14
- 16
- 18
One screen location corresponds to a
- Byte
- Word
- Double type
- Double word
When an item is pushed on the decrementing stack, the top of the stack is
- First decremented and then element copied to the stack
- First incremented and then element copied to the stack
- decremented after the element copied to the stack
- incremented after the element copied to the stack
Each screen location corresponds to a word, the lower byte of this word contains _________.
- The character code
- The attribute byte
- the parameters
- The dimensions
If ax contains decimal -2 and BX contains decimal 2 then after the execution of
Instruction: CMP AX, BX, JA label
- Jump will be taken
- Zero flag will set
- 2F will contain value -4
- Jump will not be taken
Only instructions allow moving data from memory to memory.
- String
- Word
- Indirect
- Stack
In a video memory, each screen location corresponds to _______
- One byte
- Two bytes
- Four bytes
- Eight bytes
mov ax,5 has
- 1 operand
- 2 operand
- 3 operand
- 4 operand
The physical address of the stack is obtained by
- SS:SI combination
- SS:SP combination
- ES:BP combination
- ES:SP combination
Index registers are used to store _____________
- Data
- Intermediate result
- Address
- Both data and addresses
When a 32 bit number is divided by a 16 bit number, the quotient is of
- 32 bits
- 16 bits
- 8 bits
- 4 bits
If the direction of the processing of a string is from higher addresses towards lower addresses then
- ZF is cleared
- DF is cleared
- ZF is set
- DF is set
The instruction ADC has ________ Operand(s)
- 0
- 1
- 2
- 3
Which bit of the attribute byte represents the red component of background color?
- 3
- 4
- 5
- 6
In STOS instruction, the implied source will always be in
- AL or AX registers
- DL or DX registers
- BL or BX registers
- CL or CX registers
When a 32 bit number is divided by a 16 bit number, the quotient will be store in
- AX
- BX
- CX
- DX
“mov byte [num1], 5” is ______ instruction.
- Legal
- Illegal
- Stack bases
- Memory indirect
To transfer control back the RET instruction take
- 1 argument
- 2 arguments
- 3 arguments
- No arguments
The maximum parameters a subroutine can receive (with the help of registers) are
- 6
- 7
- 8
- 9
The basic function of SCAS instruction is to
- Compare
- Scan
- Sort
- Move data
The bits of the ____________ work independently and individually.
- Index register
- Base register
- Flags register
- Accumulator
To convert any digit to its ASCII representation
- Add 0x30 in the digit
- Subtract 0x30 from the digit
- Add 0x61 in the digit
- Subtract 0x61 from the digit
Each screen contains location corresponds to a word, the lower byte of this word contains _____
- The character code
- The attribute byte
- The parameters
- The dimensions
JC and JNC test the _____________ flag.
- Carry
- Parity
- Zero
- Sign
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
___________ register holds the address of next instruction is to be executed
- Base pointer
- Code segment
- Source index
- Program counter
The clear screen operation initializes whole block of video memory to
- 0417
- 0714
- 0721
- 0174
The 8088 processor divides interrupts into _____ classes.
- One
- Two
- Three
- Four
Which of the following directive used to reserve a 8 bit space in the memory holding data?
- Db
- dw
- dd
- dq
- The base pointer accesses local variables using _______ offsets.
Negative
2. Which of the following describes the purpose of MOVS instruction?
Move memory to memory
3. Which part of this (0000000B80500) encoded instruction is an offset?
0500
4. Stack is a data structure that behaves a first in last _______ manner. Out
5. In the instruction “mov word [es:160], 0x1230”, 30 represents ______ character. 0
6. Multiplying two 4 bit numbers result in a ________ bit number.
8
7. In case of near jump, the relative address is stored in _______ bits.
16
8. _______ instructions have two parameters, one is the general purpose register to be loaded and the other is the memory location from which to load these registers.
LDS
9. Physical memory address is of
20 bit
10. ________ ports which interface the processor to the external world, including keyboards, mice, monitors, disc drives.
Input, outpu
11. In base+offset addressing, the value contained in the base register is add with offset to get ______.
Effective address
12. In 8051, there is an _________ stack. Incrementing
13. AX register can be divided into ______ and _____ bytes
Lower, higher
14. CLI stands for
Clear the interrupt flag
15. When a 32 bit number is divided by a 16 bit number, the remainder is of
16 bits
16. MUL instruction performs an unsigned multiplication of _______ with the source operand.
Accumulator
17. DW can store ______ bit value in it.
16
18. When the stack pointer, points to the return address? When the bubble sort subroutine is called
19. IAPX88 stands for ________.
Intel Advanced Processor Extensions 88
20. 90 is the op-code of Do nothing
21. When characters are stored in any high level or low level language, the actual thing stored in a byte is their ______.
ASCII code
22. We can convert any digit to ______ by adding 0x30 in the digit.
ASCII
23. A complete _______ is called a pass over the array
Iteration
24. Which of the following is a non-destructive AND operation? Test
25. In _______ operation the carry flag is inserted from the right causing every bit to move one location to its left and the most significant bit occupying the carry flag. Rotate Through Carry Left (RCL)
26. ASCII table is the contiguous arrangement of the uppercase alphabets (41-5A), the lowercase alphabets (61-7A), and the numbers _________.
30-39
27. _______ can also be used as a masking operation to invert selective bits.
XOR
28. BH register is a _______ bit register.
8
29. Which of the following is the renamed version of conditional jump JZ?
JE
30. SP is associated (by default) with _______.
SS
31. The maximum amount of memory accessible using 8085 processor is ________.
64 KB
32. In XOR operation the output is 1 if
Both inputs are different
33. The clear screen operation initializes whole block of video memory to:
0720
34. The 8088 processor divides interrupts into ______ classes.
Two
35. Which of the following directive is used to reserve a 8 bit space in the memory for holding data?
db
36. All mathematical and logical operations are performed on the _______
Accumulator
37. ______ jump is not position relative but is absolute
Far
38. Which of the following bit that “Shift Logical Right” operation copies in the carry flag?
Right most bit
39. Which of the following register is used to hold address of the next instruction to be executed?
Program counter
40. Group of bits processor uses to inform memory which element to read/write is collectively known as
Address bus
41. _________ containing the address of the next instruction to be executed. Instruction pointer (IP)
42. To convert the case of a character, we add or subtract ________ from its ASCII code.
0x20
43. Which of the following instruction is effectively same as to multiply the value of AX by 8?
SHL AX, 8
MUL AX,3
44. ______ interrupts are those which occur side by side with some other activity.
Synchronous
45. During CALL operation, the current value of the _________ is automatically saved on the stack, and the destination of CALL is loaded in the instruction pointer.
Instruction pointer
46. In SCAS Example, we use SCASB with _____ and a zero in AL register to find a zero byte in a string
REPNE
47. In interrupt vector table. Introducing a new entry in this mapping table is called ______an interrupt.
Hooking
48. What does the following instruction do? ADD AX. BX
Add both registers and load value into ax register
49. The process through which the segment register can be explicitly specified as known as
Segment addressing
50. REPE and REPNE prefixes are only meaningful with _______.
CMPS
51. ________ refers to the total number of bits in a memory cell.
Cell width
52. The _______ operation is about shifting 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.
Shift Arithmetic Right (SAR)
53. _____ and _____ cannot be used as 8bit register pairs like AX, BX, CX, and DX.
SI, DI
54. AX and BX both are 16-bit register, if we perform AND operation on these two registers, then how many AND operations will be performed?
16 And operation
55. 8085 can access up to _______ of memory, whereas 8088 can access up to ________ of memory.
64Kb, 1Mb
56. CS and IP are both ______ bit registers.
16
57. In 8080, there is a _____ stack.
Decrementing
58. An important role of the stack is in the creation of ____variables that are only needed while the subroutine is in execution and not afterward.
Local
59. ____ movement of data is not allowed in assembly language.
Memory-to-Memory
60. With the execution of CALL instruction, the value of____ is decremented by 2.
SP
61. In interrupt vector table, introducing a new entry in the mapping table is called____ an interrupt.
Hocking
62. Which of the following is the most illegal instruction? Mov al, ax
63 Motorola follows____
Big endian
64. Which of the following instruction allows code reusability in 8088?
CALL
65. When the first thing popped off from the stack, the stack would be the return “address” and not the ____
Argument
66. ___ decrements SP (the stack pointer) by two and then transfers a word from source operand to the top of stack now pointed to by SP,
PUSH
67. Which of the following is a Program Control Instruction?
cmp ax,0
68. Logical addressing is a mechanism to access ___ memory.
Physical memory
69. In assembly language “JN2” is used to Jump if the zero flag is not set
70. In segmented memory model, the size of one window is restricted to ______.
64 KB
71. Twenty-bit register is formed by the combination of two ___ bit register.
Sixteen
72. MOV[BX+SI+300],AX is a _____ addressing mode instruction.
Base + index + offset
73. Physical address calculating depends on
Effective address
74. There are ____ registers in iAPX88 architecture that can hold address of data.
4
75. ____ also known as source operand since the data is moving to stack from this operand.
PUSH
76. By default CS is associated with
IP
77. The stack pointer contains the address of the word that is currently on ______.
Top the stack
78. If AX=OOFF, then which of the following instruction can be used to change the value of AX to FFOO
ANDAX, FFOO
79. All addressing mechanisms in iAPX88 return a number called ___ address.
Effective
80. In 8088 processor, interrupts are divided into the following classes. Software Interrupts, Hardware Interrupts
81. Which of the following is the interrupt number for NMI? INT 3
82. here are ___ registers in IAPX88 architecture that can hold address of data. 4
83. Use of AND operation to make selective bits zero in its destination operand is known as_____.
Selective Bit Clearing
84. Standard ASCII has ____ characters? 128
85. ____ is used to store both the instructions to be executes by the microprocessor and the data to be used in the computation.
Microprocessor
86. Number of operands of ADC ( add with carry) register are: 3
87. DX play an important role in arithmetic
Addition.
88.Stack is a
Data Structure
89. REPE or REPNE are used with the ————instructions
SCAS
90. __________Instruction have two parameters, one is the general purpose register to be loaded and other is the memory location from which to load these registers
LDS
91. Keywords used to define two bytes program
DW
92. The shift logical left operation is the exact______ of shift logical right
Opposite
94. Sending the appropriate signal on the control bus to the memory is the responsibility of Control Bus
95. A parallel port has ——- views
2
96. The mechanism used to drop carry for making the calculated address valid is known is
address wraparound
97. In________ a zero is inserted form right and every bit moves one position to its left wth most significant but dropping in to carry flag
Both SHL and SAL
98. The reduction in code size and the improvement in speed are the two reasons why block processing instruction were introduced in the _____ Processor
8080
99. Mov ax, [NUM1] is a ______ bit move instruction.
16
100. Which of the following is the interrupt number for debug interrupt
INT 3
101. Each entry of the interrupt vector table is of ____ bytes
4
102. If BL contains 000000101 then after a Singe Right Shift, BL will contain
00000010
103. ______can be used to check weather particular bit of number are set or not
AND
104. When the relative address stored with the instruction is in 16 bit , the jump is called a ______jump
Near
105. The Stack of 8088 works on ___Sized element
Word
105. The interrupt call loads new values in segment
Flag
106. Mov AX, 0XB800, Move ES, AX : this instruction points ES to
Video Base
107. When the operant of DIV instruction is of 16 bits then implied dividend will be of
Bits
8
108. Which bit is attribute but representing the blue component of foreground color
0
109. When the operand of DIV instruction is of 16-bits then implied dividend will be stored in
AX Register
110. Constant can never be used as
destination
111. DB-25 is a _____Port Connector
Parallel
112. Flag register is a special register in every architecture ,, is as also known as
Program Status Word
113. BP stands for
base pointer
114. Intel follows
little endian
115. Mov [1234].ax is an example of
direct addressing
- 116. OR is used to clear any specific bit in a binary number
117. In general the memory cell cannot be wider than the width of the
data bus.
118. Source operand always resided in
accumulator register
119. ________always resided in accumulator register
source operand
120. INT instruction takes _____argument varying from 0-255.
1 byte
122. Program consists of
logical parts
123. 8088 provides a mechanism for mapping interrupts to interrupt handlers is called h
hooking an interrupt.
124. The routine that executes in response to an INT instruction is called the ________or_____
interrupt service routine (ISR) , the interrupt handler.
125. The push operation copies its operand on the stack , while the____operation makes a copy from the top of the stack into its operand.
pop
126. ROR : in the rotate right operation every bit moves one position to the right and the bit dropped from the right is inserted at the left and also copied into the carry flag.
127. The segment, offset pair is called a
logical address
128. the local variables and the parameters are always stored in
stack segment
129. SCAS compares a source byte or word in register AL or AX with the destination string element addressed by ES:DI and updates the flags.
130. JNP and JPO is taken if the last arithmetic operation produced a number in its destination that has
odd parity
130. JP and JPE is taken if the last arithmetic operation produced a number in its destination that has
even parity.
131. There are two forms of the DIV instruction.
132. Unconditional jump
always transfer the control
133. The group of bits that the processor uses to inform the memory about which element to read or write is collectively known as the
address bus.
134. ADC has three operands
135. In direct addressing the memory address given in the instruction is
fixed
136. In which of the following addressing, the memory address is fixed and is given in the instruction?
Direct
137. _______pair of registers used to access memory
DI and SI
138. Total number of cells is called the
depth
139. ________copies the______in the carry flag
Shift Logical Right (SHR) , right most bit
140. REP with _______ will utilize the full processor power to do the scrolling in minimum time.
MOVS
141. The correlation process from the interrupt number to the interrupt handler uses a table called
interrupt vector table
142. POP is also known as
destination operand
143. The parallel port connector is a 25pin connector called
DB-25
144. The _________port connector is a 25pin connector called DB-25
parallel
145. There are just ______ block processing instructions in 8088.
5
146. Interrupts are ______and unpredictable
asynchronous
147. ______instruction allows code reusability in 8088
CALL
148. Program Control Instructions
cmp ax, 0
149. In MULTIPLICATION ALGORITHM ,We take the first digit of the multiplier and multiply it with the
multiplicand
150. _______jump is taken if the last arithmetic operation changed the sign unexpectedly.
JO
151. ______is a special instructions
CLI
152. the interrupt call loads new values in
CS
153. A 32bit processor has an accumulator of
32 bits.
154. Left shift on hexa-decimal number 9C40 ans is
0x13880
154. Each entry of the table is of ____bytes
four
155. Video Graphics Adapter
VGA.
156. The instruction “mov [bp], al” moves the one byte content of the AL register to the address contained in the BP register in the current
stack segment.
158. STI stands for
Set Interrupt Flag
159. Flags register is a special register in every architecture, it is also known as
program status word
160. A special register exists in every processor called
the program counter or the instruction pointer
161. mov word [es:160], 0x1230 12 meaning
green color on blue background.
162. ______can store 16 bits
DW
163. two variants of STOS are ______and_____STOSB, STOSW
164. Another important role of the stack is in the creation of _____that are only needed while the subroutine is in execution and not afterwards.
local variables
165. In Far jump
both offset and segment are given
167. to multiply a number in register by 2 the number is
shift left one bit
168. In case of downward compatible mechanism, the codes written for 8080 are ______for 386 processor
Valid
169. Interrupt hooking is the mechanism that is used for mapping interrupt to interrupt handler
170. Which of the following statement is used to clear the value of AX register, xor ax,
0
171. Which assembly instruction is used to ADD data at address 1200 to bx register
add bx, [1200]
172. Chose the correct option from the following addressing modes , from which both register moves into the data segment
base+offset
173. _______operation , a carry flag is inserted from left moving every bit one position to the right, with the right most bit is dropped in carry flag
RCR
175. After the execution of SAR
instruction most significant bit retains its original value
175. _____is the part of microprocessor that ménages the execution of instruction
Control unit
176. In a comparison, if the both operands are same , the result of subtraction will be zero and the zero flag will be
set
177. When SI and DI are used, we name the method
Indexed Addressing
178. Which combination will you prefer to obtain the physical address of the stack
SS:SP
179. Whenever we need access to a memory location whose address is not know until run time we use
index register
180. Interrupts are________event
asynchronous
181. During program execution , if any change in AH or AL is reflected in_______as Well
AX
182. Basic function of register is to
hold operand
183. Which among the following is the pointer registers?
index pointer and decession pointer
184. mov [bx], ax moves the two bytes content of AX register to the address contained in BX register in the current
data segment
185. in string manipulation the instruction to clear the direction flag is
CLD
186. If A is subtracted from B and the resulting answer is negative figure it means B is
small number
187. in ___ operation the output is 1 only if only if both inputs are 1 ?
AND
188. The interrupt call loads new values in CS, IP, and
FLAGS.