Intro to Hardware Description Language

A bit in a computer terminology means either 0 or 1.

• True
• False

Which of the circuits in figure (a to d) is the sum-of-products implementation of figure (e)?

• d
• c
• b
• a

7’s complement of 432 is _________________

• 345
• 432
• 543
• 777

Boolean Function is of the form of ________

• Truth values
• Algebraic Expression
• Truth Table
• K=f(X,Y,X)

Convert (52)16 into its decimal equivalent.

• 80
• 28
• 82
• 83

The minterm of any expression is denoted by ___________

• Mt
• m
• min

The following figure shows a ___________ gate.

• NOR
• OR
• NAND
• EXOR

It is rooted in binary code, a series of zeroes and ones each having an opposite value.

• Numeric System
• Decimal Base
• Radix Number System
• Digital Logic

What type of logic circuit is represented by the figure shown below?

• AND
• NAND
• XNOR
• XOR

In parts of the processor, adders are used to calculate ____________

• Addresses
• All of the Mentioned
• Increment and decrement operators
• Table indices

2’s complement is obtained by adding 1 to 1’s complement of a number.

• True
• False

When both inputs of a J-K flip-flop cycle, the output will ___________

• Be invalid
• Toggle
• Change
• Not change

Which of the following gates has the exact inverse output of the OR gate for all possible input combinations?

• AND
• NOR
• NAND
• NOT

A digital multiplexer is a combinational circuit that selects ___________

• Many decimal inputs and transmits the selected information
• One digital information from several sources and transmits the selected one
• Many digital information and convert them into one
• Many decimal outputs and accepts the selected information

What is the indication of a short to ground in the output of a driving gate?

• There is a signal loss to all load gates
• Only the output of the defective gate is affected
• The affected node will be stuck in the HIGH state
• The node may be stuck in either the HIGH or the LOW state

The 32 bit representation of the decimal number is called as ____

• Extended format
• None of the mentioned
• Double-precision
• Single-precision

The carry propagation can be expressed as ________

• Cp = AB
• All but Y0 are LOW
• Cp = A + B
• All but Y0 are HIGH

For the device shown here, assume the D input is LOW, both S inputs are LOW and the input is LOW. What is the status of the Y’ outputs?

• All are HIGH
• All but Y0 are LOW
• All are LOW
• All but Y0 are HIGH

If a 3-input NOR gate has eight input possibilities, how many of those possibilities will result in a HIGH output?

• 7
• 2
• 1
• 8

What does the symbol D represent in a hexadecimal number system?

• 8
• 14
• 13
• 16

The maximum number of bits sufficient to represent a hexadecimal number in binary:

• 3
• 8
• 7
• 4

The input hexadecimal representation of 1110 is _______________

• E
• 14
• 0111
• 15

Which of the following is a data transfer instruction?

• RET
• STA 16-bit address
• ADD A, B
• MUL C, D

ABC is a valid hexadecimal number.

• True
• False

In a number system, each position of a digit represents a specific power of the base.

• True
• False
• 82 * 1 + 81 * 1 + 80 *3.

If a 3-input AND gate has eight input possibilities, how many of those possibilities will result in a HIGH output?

• 2
• 7
• 1
• 8

Latches constructed with NOR and NAND gates tend to remain in the latched condition due to which configuration feature?

• Synchronous operation
• Gate impedance
• Low input voltages
• Cross coupling

The logic circuits whose outputs at any instant of time depends only on the present input but also on the past outputs are called

• Combinational circuits
• Latches
• Sequential circuits
• Flip-flops

What could be the maximum value of a single digit in an octal number system?

• 6
• 7
• 8
• 5

In the IEEE floating point representation, the hexadecimal value 0 × 00000000 corresponds to

• the normalized value +0
• the special value +0
• the normalized value 2-127
• the normalized value 2-126

The result obtained on subtraction using 2’s complement of 1111-0010 will be _________

• 11011
• 1011
• 11101
• 1101

The value of radix in binary number system is _____________

• 2
• 8
• 1
• 10

The _________ holds the contents of the accessed memory word.

• PC
• MBR
• IR
• MAR

For voice, each channel contains a ___ word of digitized data.

• 1
• 2
• 4
• 0

The word demultiplex means ___________

• One into many
• Distributor
• One into many as well as Distributor
• Many into one

Which is the major functioning responsibility of the multiplexing combinational circuit?

• Decoding the binary information
• Generation of selected path between multiple sources and a single destination
• Generation of all minterms in an output function with OR-gate
• Encoding of binary information

The number of sign bits in a 32-bit IEEE format __________

• 1
• 11
• 9
• 23

There are 5 universal gates.

• True
• False

In TDM, the samples occupy adjacent time slots.

• True
• False

It is possible for an enable or strobe input to undergo an expansion of two or more MUX ICs to the digital multiplexer with the proficiency of large number of ___________

• Inputs
• Selection lines
• Enable lines
• Outputs

Number of outputs in a half adder _____________

• 1
• 3
• 2
• 0

The Boolean expression for a 3-input AND gate is ________.

• X = A + B + C
• X = ABC
• X = AB
• X = AB + C

The binary equivalent of the decimal number 10 is __________

• 1010
• 10
• 0010
• 010

Let r denote number system radix. The only value(s) of r that satisfy the equation 12

• any value > 2
• decimal 10
• decimal 11
• decimal 10 and 11

The device shown here is most likely a ________

• Inverter
• Multiplexer
• Comparator
• Demultiplexer

What is a multiplexer?

• It is a type of decoder which decodes several inputs and gives one output
• A multiplexer is a device which converts many signals into one
• It is a type of encoder which decodes several inputs and gives one output
• It takes one input and results into many output

The number of literals in the expression F=X.Y’ + Z are _____________

• 3
• 4
• 2
• 1

The 1’s complement of 1111111110.101 is _______________

• 1.101
• 1111111110.101
• 0000000000.010
• 1.010

A ____________ is a circuit with only one output but can have multiple inputs.

• Truth table
• Logic gate
• Binary circuit
• Boolean circuit

A computer language that is written in binary codes only is _____

• C
• Pascal
• C#
• machine language

If a signal passing through a gate is inhibited by sending a LOW into one of the inputs, and the output is HIGH, the gate is aNo:

The ________ gate is an OR gate followed by a NOT gate.

• EXOR
• EXNOR
• NOR
• NAND

The numbers written to the power of 10 in the representation of decimal numbers are called as _____

• Size factors
• Height factors
• Scale factors
• None of the mentioned

The format used to present the logic output for the various combinations of logic inputs to a gate is called aNo:

• Boolean variable
• truth table
• Boolean constant
• input logic function

A basic S-R flip-flop can be constructed by cross-coupling of which basic logic gates?

• AND or OR gates
• XOR or XNOR gates
• AND or NOR gates
• NOR or NAND gates

The general form for calculating the number of rows in a truth table is ________

• 2n
• -2n
• 2n+1
• 2n-1

The decimal value 0.5 in IEEE single precision floating point representation has

• fraction bits of 100…000 and exponent value of 0
• fraction bits of 000…000 and exponent value of −1
• fraction bits of 000…000 and exponent value of 0

Which of the following is correct for a gated D-type flip-flop?

• The output complement follows the input when enabled
• Only one of the inputs can be HIGH at a time
• The output toggles if one of the inputs is held HIGH
• The Q output is either SET or RESET as soon as the D input goes HIGH or LOW

Most demultiplexers facilitate which type of conversion?

• Odd parity to even parity
• Single input, multiple outputs
• Decimal-to-hexadecimal
• AC to DC

The output of an OR gate with three inputs, A, B, and C, is LOW when ________.

• all of the above
• A = 0, B = 1, C = 1
• A = 0, B = 0, C = 1
• A = 0, B = 0, C = 0

What is the 1’s complement of 11010?

• 11011
• 00101
• 11010
• 00110

3 bits full adder contains ________

• 3 combinational inputs
• 8 combinational inputs
• 6 combinational inputs
• 4 combinational inputs

In double precision format, the size of the mantissa is ______

• 64
• 52 bit
• 72
• 32 bit

The complement term for X’.Y’.Z + X.Y will be _____________

• (X+Y+Z’)(X’+Y)
• (X+Y+Z’)(X’+Y’)
• XYZ’+X’Y’

In the boolean function w=f(X,Y,Z), what is the RHS referred to as ________

• boolean
• expression
• right hand side
• literals

>> operator is used to denote _________

• less than
• greater than
• right shift
• left shift

Which of the following combinations of logic gates can decode binary 1101?

• One 4-input NAND gate, one inverter
• One 4-input AND gate, one OR gate
• One 4-input AND gate
• One 4-input AND gate, one inverter

The expression of a NAND gate is_______

• (A.B)’
• A’B+AB’
• (A+B)’
• A.B

The max term when X=Y=Z=1 is ________

• xyz
• x’y’z’
• x’+y’+z’
• x+y+z

In 1-to-4 demultiplexer, how many select lines are required?

• 5
• 3
• 4
• 2

In the hexadecimal system, we allow _______ values for each digit of a number

• 2
• 16
• 8
• 10

The output of a NOR gate is HIGH if ________.

• any input is LOW
• all inputs are HIGH
• any input is HIGH
• all inputs are LOW

Which of the following logic expressions represents the logic diagram shown?

• X=A’B’+AB
• X=(AB)’+A’B’
• X=(AB)’+AB
• X=AB’+A’B

Whose operations are more faster among the following?

• Latches
• Sequential circuits
• Combinational circuits
• Flip-flops

The smallest integer that can be represented by an 8-bit number in 2’s complement form is

• -128
• -127
• 0
• -256

How many AND gates are required to realize the following expression Y=AB+BC?

• 4
• 8
• 2
• 1

Controlling the frequency is referred as _________

• phase modulation
• hertz modulation
• amplitude modulation
• frequency modulation

In this type of multiplexing time slots are preassigned to sources and fixed.

• Asynchronous TDM
• FDM
• Synchronous TDM
• TDM

The 16’s complement of 74E will be __________

• F8B2
• 2B8
• 8B2
• 8C2

One example of the use of an S-R flip-flop is as ___________

• Switch debouncer
• Racer
• Transition pulse generator
• Astable oscillator

The normalized representation of 0.0010110 * 2 9 is _______

• 0 10101010 1110
• 0 10001000 0010110
• 0 10000101 0110
• 0 11110100 11100

One multiplexer can take the place of ___________

• Several Ex-NOR gates
• Several SSI logic gates or combinational logic circuits
• Combinational logic circuits
• Several SSI logic gates

In this technique, there is a link between subscriber and network and a local loop.

• DSDL
• SSDL
• TSDL
• ASDL

WDM stands for?

• Wavelength division multiplexing
• Wave division multiplexing
• Wave dependent multiplexing
• Wavelength dependent multiplexing

What kind of a flag is the sign flag?

• Status
• Instruction
• General Purpose
• Address

New CPU whose instruction set includes the instruction set of its predecessor CPU is said to be ___________ with its predecessor.

• fully compatible
• backward compatible
• compatible
• forward compatible

How many select lines would be required for an 8-line-to-1-line multiplexer?

• 3
• 8
• 4
• 2

Convert the binary number 11001 to decimal.

• 3
• 25
• 15
• 13

The Output is LOW if any one of the inputs is HIGH in case of a _________ gate.

• AND
• NAND
• NOR
• OR

Which combinational circuit is renowned for selecting a single input from multiple inputs & directing the binary information to output line?

• DeMultiplexer
• Both data selector and data distributor
• Data Selector
• Data distributor

How many types of sequential circuits are?

• 5
• 2
• 4
• 3

The binary number 1110 in hexadecimal format is _____________

• 15
• 14
• 6
• E

Which of the following is not a binary number?

• 101
• 000
• 1111
• 11E

The length of a register is called _______

• word size
• word limit
• register limit
• register size

For a two-input XNOR gate, with the input waveforms as shown below, which output waveform is correct?

• a
• b
• c
• d

Convert 111 110 010 from base 2 to base 8

• 215
• 762
• 125
• 672

Why is a demultiplexer called a data distributor?

• One of the inputs will be selected for the output
• The input will be distributed to one of the outputs
• Single input to Single Output
• The output will be distributed to one of the inputs

The octal equivalent of 1100101.001010 is ______

• 624.12
• 145.12
• 154.12
• 145.21

The truth table for an S-R flip-flop has how many VALID entries?

• 2
• 1
• 3
• 4

What is the complement of X’Y’Z?

• XYZ’
• X+Y+Z’
• X’+Y+’Z’
• X+YZ

Which of the following is the correct representation of a binary number?

• 1110
• (000)2
• (124)2
• (110)2

The sequential circuit is also called ___________

• Flip-flop
• Latch
• Adder
• Strobe

How many AND, OR and EXOR gates are required for the configuration of full adder?

• 3, 1, 2
• 1, 2, 2
• 2, 1, 2
• 4, 0, 1

The output of an AND gate with three inputs, A, B, and C, is HIGH when ________.

• A = 1, B = 1, C = 0
• A = 1, B = 1, C = 1
• A = 1, B = 0, C = 1
• A = 0, B = 0, C = 0

What is correct instruction if you want the control to go to the location 2000h?

• RET 2000h
• JMP 2000h
• MOV 2000h
• MOV A, 2000h

The subtraction using 1’s complement of 110 – 100 will give the result ___________

• -010
• -011
• 010
• 011

The 10’s complement of 562 is __________

• 3
• 7
• 4
• 8

Convert (22)8 into its corresponding decimal number.

• 18
• 28
• 82
• 81

The 9’s complement of 6578 is ___________

• 3124
• 1234
• 3420
• 3421

In a multiplexer the output depends on its ___________

• Select outputs
• Enable pin
• Select inputs
• Data inputs

The complement of the input given is obtained in case of:

• EX-OR
• NOR
• AND+NOR
• NOT

Opcode indicates the operations to be performed.

• True
• False

A system in which two channels are dedicated to transfer data.

• TV
• Cable
• Cable modem
• Modem

The result of X+X.Y is X.

• True
• False

The binary number 111 in octal format is ________________

• 8
• 5
• 7
• 6

Which of the following correctly describes the distributive law.

• (AB)(A+B)=AB
• (A+B).C=AC+BC
• ( A+B)(C+D)=AB+CD
• (A.B)C=AC.AB

Many time slots are wasted in __________

• FDM
• Synchronous TDM
• TDM
• Asynchronous TDM

Output will be a LOW for any case when one or more inputs are zero for aNo:

• NOR Gate
• OR Gate
• AND Gate
• NOT Gate

Which of the following logical operations is represented by the + sign in Boolean algebra?

• complementation
• OR
• AND
• inversion

A technique that can be a solution to the problem of synchronizing data sources.

• pulse stuffing
• data link control
• framing
• full link control

A technique that allocates time slots dynamically.

• Statistical TDM
• TDM
• WDM
• Dynamic TDM

P is a 16-bit signed integer. The 2's complement representation of P is (F87B)16.The 2's complement representation of 8*P

• (C3D8)16
• (F878)16
• (987B)16
• (187B)16

CPU has built-in ability to execute a particular set of machine instructions, called as __________

• Instruction Set
• User instructions
• Registers
• Sequence Set

The min term when X=Y=Z=0 is _____________

• x’+y’+z’
• x+y+z
• xyz
• x’y’z’

What is the function of an enable input on a multiplexer chip?

• To connect ground
• To apply Vcc
• To active one half of the chip
• To active the entire chip

Which of the following is not a positional number system?

• Hexadecimal Number System
• Roman Number System
• Binary Number System
• Octal Number System

(1217)8 is equivalent to

• (2297)10
• (1217)16
• (028F)16
• (0B17)16

Convert the binary equivalent 10101 to its decimal equivalent.

• 31
• 22
• 21
• 12

Which of the following is not a visible register?

• Address Register
• General Purpose Registers
• MAR
• Status Register