Intro to Hardware Description Language

The expression of a NAND gate is_______

• (A.B)’
• A’B+AB’
• (A+B)’
• A.B

Most demultiplexers facilitate which type of conversion?

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

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

• 1
• 11
• 9
• 23

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

• 3
• 8
• 7
• 4

The device shown here is most likely a ________

• Inverter
• Multiplexer
• Comparator
• Demultiplexer

>> operator is used to denote _________

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

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

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

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

How many types of sequential circuits are?

• 5
• 2
• 4
• 3

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

The minterm of any expression is denoted by ___________

• Mt
• m
• min

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

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

• 11011
• 1011
• 11101
• 1101

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

• True
• False

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 length of a register is called _______

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

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

• -010
• -011
• 010
• 011

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

Convert (52)16 into its decimal equivalent.

• 80
• 28
• 82
• 83

In TDM, the samples occupy adjacent time slots.

• True
• False

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

• d
• c
• b
• a

What kind of a flag is the sign flag?

• Status
• Instruction
• General Purpose
• Address

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

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

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

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

• 1110
• (000)2
• (124)2
• (110)2

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

• a
• b
• c
• d

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

3 bits full adder contains ________

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

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

• AND
• NAND
• XNOR
• XOR

The 1’s complement of 1111111110.101 is _______________

• 1.101
• 1111111110.101
• 0000000000.010
• 1.010

The normalized representation of 0.0010110 * 2 9 is _______

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

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

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

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

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

• 3
• 4
• 2
• 1

The value of radix in binary number system is _____________

• 2
• 8
• 1
• 10

There are 5 universal gates.

• True
• False

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 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

Convert 111 110 010 from base 2 to base 8

• 215
• 762
• 125
• 672

What is the complement of X’Y’Z?

• XYZ’
• X+Y+Z’
• X’+Y+’Z’
• X+YZ

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

• AND
• NAND
• NOR
• OR

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

• -128
• -127
• 0
• -256

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

• EXOR
• EXNOR
• NOR
• NAND

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

• Be invalid
• Toggle
• Change
• Not change

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

In a multiplexer the output depends on its ___________

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

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

Which of the following is a data transfer instruction?

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

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

• AND
• NOR
• NAND
• NOT

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

• 6
• 7
• 8
• 5

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

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

Controlling the frequency is referred as _________

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

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

• 2
• 16
• 8
• 10

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

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

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

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

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

Convert the binary equivalent 10101 to its decimal equivalent.

• 31
• 22
• 21
• 12

The binary number 111 in octal format is ________________

• 8
• 5
• 7
• 6

Convert (22)8 into its corresponding decimal number.

• 18
• 28
• 82
• 81

WDM stands for?

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

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

• Asynchronous TDM
• FDM
• Synchronous TDM
• TDM

The result of X+X.Y is X.

• True
• False

What is the 1’s complement of 11010?

• 11011
• 00101
• 11010
• 00110

The 10’s complement of 562 is __________

• 3
• 7
• 4
• 8

Which of the following is not a positional number system?

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

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 binary equivalent of the decimal number 10 is __________

• 1010
• 10
• 0010
• 010

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

ABC is a valid hexadecimal number.

• True
• False

7’s complement of 432 is _________________

• 345
• 432
• 543
• 777

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

• TV
• Cable
• Cable modem
• Modem

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

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

• complementation
• OR
• AND
• inversion

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

Opcode indicates the operations to be performed.

• True
• False

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

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

• 64
• 52 bit
• 72
• 32 bit

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

• 1
• 2
• 4
• 0

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 sequential circuit is also called ___________

• Flip-flop
• Latch
• Adder
• Strobe

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

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

• C
• Pascal
• C#
• machine language

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

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

Many time slots are wasted in __________

• FDM
• Synchronous TDM
• TDM
• Asynchronous TDM

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

• boolean
• expression
• right hand side
• literals

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 complement of the input given is obtained in case of:

• EX-OR
• NOR
• AND+NOR
• NOT

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

• x’+y’+z’
• x+y+z
• xyz
• x’y’z’

The following figure shows a ___________ gate.

• NOR
• OR
• NAND
• EXOR

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

Boolean Function is of the form of ________

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

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

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

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

• 8
• 14
• 13
• 16

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

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

The word demultiplex means ___________

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

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

• DSDL
• SSDL
• TSDL
• ASDL

(1217)8 is equivalent to

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

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

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

• 5
• 3
• 4
• 2

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

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

Number of outputs in a half adder _____________

• 1
• 3
• 2
• 0

Which of the following is not a visible register?

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

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

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

• 3
• 8
• 4
• 2

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

The octal equivalent of 1100101.001010 is ______

• 624.12
• 145.12
• 154.12
• 145.21

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

• xyz
• x’y’z’
• x’+y’+z’
• x+y+z

The binary number 1110 in hexadecimal format is _____________

• 15
• 14
• 6
• E

The 9’s complement of 6578 is ___________

• 3124
• 1234
• 3420
• 3421

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

• 4
• 8
• 2
• 1

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

The _________ holds the contents of the accessed memory word.

• PC
• MBR
• IR
• MAR

Convert the binary number 11001 to decimal.

• 3
• 25
• 15
• 13

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

• 2
• 1
• 3
• 4

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

• True
• False

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

Whose operations are more faster among the following?

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

A technique that allocates time slots dynamically.

• Statistical TDM
• TDM
• WDM
• Dynamic TDM

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

The 16’s complement of 74E will be __________

• F8B2
• 2B8
• 8B2
• 8C2

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

• Instruction Set
• User instructions
• Registers
• Sequence Set

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

The input hexadecimal representation of 1110 is _______________

• E
• 14
• 0111
• 15

Which of the following is not a binary number?

• 101
• 000
• 1111
• 11E

The carry propagation can be expressed as ________

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

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

• 2n
• -2n
• 2n+1
• 2n-1