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Syllabus

NEC Electronics · Practice

Chapters & sets

1. Basic Electrical and Electronics Engineering

Basic Electrical

Set 1106

Basic Electronics

Set 171 Set 233

2. Digital Logic and Microprocessor

Digital Logic

Set 150 Set 250 Set 350 Set 450 Set 550 Set 650 Set 749 Set 851 Set 950 Set 1050 Set 1150 Set 1232

Microprocessor

Set 150 Set 250 Set 350 Set 445 Set 550 Set 650 Set 720 Set 850 Set 969

3. Programming Language and Its Applications

Mixed chapter MCQs

Set 150 Set 249 Set 349 Set 451 Set 540

4. Computer Organization and Embedded Systems

Mixed chapter MCQs

Set 150 Set 249 Set 350 Set 450 Set 550 Set 650 Set 750 Set 849 Set 950 Set 1050 Set 1150

5. Computer Networks and Network Security

Basic Networking

Set 150 Set 253

Advanced Networking

Set 150 Set 250 Set 350 Set 450 Set 550 Set 655

10. Project Planning, Design and Implementation

Mixed chapter MCQs Set 3

50 questions

Question 1

To achieve parallelism, one needs a minimum of

A.
2 processors
B.
4 processors
C.
3 processors
D.
None of the above

Question 2

SIMD can be used for

A.
Railway reservation
B.
Matrix multiplication
C.
Weather forecasting
D.
Both B and C

Question 3

A typical application of MIMD is

A.
Railway reservation
B.
Matrix multiplication
C.
Weather forecasting
D.
All of the above

Question 4

Let \* be defined as a*b=a+b. Let m=a*b. The value of m\*a is

A.
a+b
B.
0
C.
a
D.
1

Question 5

RST 7.5 interrupt in 8085 microprocessor executes services from interrupt vector location

A.
0000h
B.
003Ch
C.
0075h
D.
0034h

Question 6

Three main components of a digital computer system are

A.
Memory, I/O, DMA
B.
Memory, CPU, I/O
C.
ALU, CPU, memory
D.
Control circuits, ALU, registers

Question 7

Micro program is

A.
The name of a source program in micro computers
B.
The set of instructions indicating the primitive operations in a system
C.
A primitive form of macros used in assembly language programming
D.
A program of very small size

Question 8

A toggle operation cannot be performed using a single

A.
NOR gate
B.
NAND gate
C.
AND gate
D.
XOR gate

Question 9

'n' flip-flops will divide the clock frequency by a factor of

A.
(N^2)
B.
(2^N)
C.
(N)
D.
Log(N)

Question 10

Most of the digital computers do not have floating-point hardware because

A.
It is costly
B.
It is slower than software
C.
Floating-point addition cannot be performed by hardware
D.
None of the above

Question 11

An assembler that runs on one machine but produces machine code for another machine is called.

A.
Simulator
B.
Cross-compiler
C.
Emulator
D.
Boot-strap loader

Question 12

Which of the following is not typically found in the status register of a microprocessor?

A.
Overflow
B.
Negative result
C.
Zero result
D.
None of the above

Question 13

When even-parity ASCII text is transmitted asynchronously at a rate of 10 character per second over a line, what percentage of the received bits actually contain data (as opposed to overhead)?

A.
7/11
B.
700/11
C.
8/11
D.
80/11

Question 14

A subtractor is not usually present in a computer because

A.
It is expensive
B.
It is not possible to design it
C.
The adder will take care of subtraction
D.
None of the above

Question 15

Let an (a_{n-1}, \ldots, a_1) be the binary representation of an integer b. The integer b is divisible by 3 if

A.
The number of one’s is divisible by 3
B.
The number of one’s is divisible by 3 but not by 9
C.
The number of zeroes is divisible by 3
D.
The difference of alternate sum, i.e., ((a_0 + a_2 + \ldots) - (a_1 + a_2 + \ldots)) is divisible by 3

Question 16

Which of the following 4-bit numbers equals its 2’s complement?

A.
1010
B.
1000
C.
No such no. exists
D.
None of the above

Question 17

Which of the following 4-bit numbers equals its 1’s complement?

A.
1010
B.
No such number exists
C.
1000
D.
None of the above

Question 18

FFFF will be the last memory location in a memory of size

A.
1 K
B.
16 K
C.
32 K
D.
64 K

Question 19

If you want to design a boundary counter, you should a prefer a flip flop of

A.
D-type
B.
Latch
C.
SR-type
D.
JK type

Question 20

Suppose the largest n-bit binary number 'd' digits in decimal representation. Which of the following relations between 'n' and 'd' is approximately correct?

A.
D=2^n
B.
D\<n log (10^2)
C.
N=2^d
D.
D>n log(10^2)

Question 21

A computer uses 8-digit mantissa and 2-digit exponent. If a=0.052 and b=28E+11, then b+a-b will

A.
Result in an overflow error
B.
0
C.
Results in an underflow error
D.
5.28E+11

Question 22

Which of the following binary numbers are not divisible by 4?

A.
10101010101010
B.
1110001110001
C.
100101100
D.
Both A and C

Question 23

A computer with a 32-bit wide data bus uses 4K x8 static RAM memory chips. The smallest memory this computer can have is

A.
32 Kb
B.
16 Kb
C.
8 Kb
D.
24 Kb

Question 24

Which of the following instructions requires the greatest number of T-states?

A.
MOV A, B
B.
LDAX B
C.
MOV A, M
D.
DAD D

Question 25

The 8085 microprocessor enters into wait state after the recognition of

A.
HOLD
B.
\*RESET-IN
C.
\*READY
D.
INTER

Question 26

Maximum number of I/O devices that can be addressed by Intel 8085 is

A.
65,536
B.
512
C.
255
D.
256

Question 27

The microprocessor may be made to exit from HALT state by asserting

A.
RESET
B.
Any of the five interrupt lines
C.
READY LINE
D.
Option (A) or option (B) or HOLD line

Question 28

The number of RAM chips of size (256 K x 1) required to build a 1 M byte memory is

A.
8
B.
10
C.
32
D.
24

Question 29

The instruction used to shift right the accumulator contents by one bit through the carry flag bit is

A.
RLC
B.
RRC
C.
RAL
D.
RAR

Question 30

The stack is nothing but a set of

A.
Reserved ROM address spaces
B.
Reserved I/O address space
C.
Reserved RAM address spaces
D.
None of the above

Question 31

The execution of RST instructions causes the stack pointer to

A.
Increment by two
B.
Remain unaffected
C.
Decrement by two
D.
None of the above

Question 32

Which one of the following instructions may be used to clear the accumulator content (i.e. A=00h) irrespective of its initial value?

A.
CLR A
B.
SUB A
C.
ORA A
D.
MOV A, 00h

Question 33

The only interrupt that is edgetriggered is

A.
INTR
B.
RST 7.5
C.
TRAP
D.
RST 5.5

Question 34

Which of the following peripheral ICs is used to interface keyboard and display?

A.
8251
B.
8259
C.
8279
D.
8253

Question 35

The contents of the A15-A8(higher order address lines) while executing "IN addr" instructions are

A.
Same as the contents of A7-A0
B.
All bits reset (i.e. 00h)
C.
Irrelevant
D.
All bits set (i.e. FFh)

Question 36

Which one of the following instructions will never affect the zero flag?

A.
DCR reg
B.
DCX rp
C.
ORA reg
D.
XRA reg

Question 37

Which one of the following interrupts is non-mask able?

A.
TRAP
B.
INTER
C.
RST 7.5
D.
RST 6.5

Question 38

RST 3 instruction will cause the processor to branch to the location

A.
0000h
B.
0024h
C.
0018h
D.
8018h

Question 39

The minimum number of bits required to represent a character from ASCII code set is

A.
2
B.
7
C.
5
D.
8

Question 40

S0 and S1 pins are used for

A.
Serial communication
B.
Acknowledgement the interrupt
C.
Indicating the processor's status
D.
None of the above

Question 41

Pick out the matching pair

A.
READY; RIM
B.
SID; SIM
C.
HOLD; DMA
D.
S0, S1; WAIT states

Question 42

Which of the following is unipolar, difficult to fabricate, has very high speed and offers good resistance to radiation?

A.
ECL
B.
TTL
C.
GaAs
D.
CMOS

Question 43

Multiplexing of data/address lines in 8085 microprocessor reduces the instructions execution time. This statement is

A.
True
B.
Most likely to be true
C.
False
D.
None of the above

Question 44

The number of flip-flops needed to construct a binary modulo N counter is

A.
N
B.
N^2
C.
2^N
D.
Log_2 N

Question 45

To change an upper-case character to a lower-case character in ASCII, the correct mast and operation should be

A.
0100000 and NOR
B.
0100000 and NAND
C.
0100000 and OR
D.
1011111 and NAND

Question 46

PCHL is an instruction in 8085 which transfers the contents of the register pair HL to PC. This is not a commonly used instruction as it changes the flow of control in a rather unstructured fashion. This instruction cannot be used in implementing

A.
If.....then......else statement
B.
Case.....structure
C.
While......do construct
D.
Call....statements

Question 47

In an 11-bit computer instruction format, the size of address field is 4 bits. The computer uses expanding OP code technique and has 5 two-address instructions and .32 one-address instructions. The number of zero address instructions it can support is

A.
256
B.
16
C.
2048
D.
272

Question 48

Which of the following instructions may be used to save the accumulator value onto the stack?

A.
PUSH PSW
B.
PUSH SP
C.
PUSH A
D.
POP PSW

Question 49

Which of the following statements is true?

A.
ROM is a read/write memory
B.
PC points to the last instruction that was executed
C.
Stack works on the principle of LIFO
D.
All instructions affect the flag

Question 50

A single instruction to clear the lower four bits of the accumulator in 8085 assembly language is

A.
XRI OFH
B.
XRI FOH
C.
ANI FOH
D.
ANI OFH

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