1) A shift register can be used for ?
a.    Serial to parallel conversion
b.    Parallel to serial conversion
c.    Digital delay line
d.    All of the above
e.    None of the above
Answer = D
Explanation:Shift registers can have both parallel and serial inputs. These are often configured as serial - in - parallel- out or parallel - in - serial - out.

2)  Semiconductor memory is-
a.    Somewhat large than the magnetic core memory
b.    A non-volatile memory
c.    Somewhat slower than magnetic core memory
d.    All of above
e.    None of these
Answer = B
Explanation: Semiconductor memory is an electronic storage device often used as computer memory. Examples of semiconductor memory is: ROM, flash memory,  magnetoresistive random-access memory (MRAM)

3) Which of the following is a universal gate  ?
a.    AND
b.    EX-OR
c.    OR
d.    NAND

Answer = D

4) The logic 1 in positive logic system is represented by ?   
a.    Zero voltage
b.    Lower voltage level
c.    Higher voltage level
d.    Negative voltage
e.    None of the above
Answer = C
Explanation:The logic 1 is represented by higher voltage while 0 is represented as low voltage.

5) Which function -positive logic is equivalent to OR function in negative logic?
a.    NOT
b.    OR
c.    AND
d.    NOR
e.    None of the above
Answer = C
Explanation: AND function performs performs as OR in negative logic.

 6) Which of the following logic expressions is wrong ?
a.    1+0=1
b.    1+1=0
c.    1+0+1=1
d.     1+1+1=1
e.    None of the above  
Answer = C
Explanation: 1+0 = 1 again this result is added to 1 as 1+1 which is equal to 0 with carry 1 but not equal to 1.

7)  A Combination logic circuit that is used when it is desired to send data from two or more source through a single transmission line is known as-
a.    Decoder
b.    Encoder
c.    Multiplexer
d.    De multiplexer
e.    None of the above
 Answer = C

8)  The m-bit parallel adder consists of-
a.    (m+1) full adders
b.    m/2 full adders
c.    m-1 full adders
d.    m full adders
e.    None of the above
Answer = D
 
9)  A logic circuit which is used to change a BCD number into an equivalent decimal number is-  
a.    Decoder
b.    Encoder
c.    Multiplexer
d.    Code converter
e.    None of the above  
Answer = A
Explanation:Decoder is used to convert the BCD numbers into decimal.

10) Which of the following property is true in context of Well Formed Formula(WFF)  ?
a.    Each letter is a term
b.    If x and y are terms then x = y is a formula
c.    If P is a formula then 7p is a formula
d.    All of above
Answer = B   

11) The term sum - of - product in Boolean algebra means ?
a.    The AND function of several OR functions
b.    The OR function of several AND functions
c.    The OR function of several OR function
d.    The AND function of several AND functions
 
Answer = B
Explanation: Sum-Of-Products expressions lend themselves well to implementation as a set of AND gates (products) feeding into a single OR gate (sum).

12) The fan out capability of a digital building block can be defined as ?
a.    The number of inputs that one output can transmit to
b.    The amount of cooling required for fanning the hear out
c.    The number of inputs that can transmit to one input
d.    The maximum power dissipation that the unit can stand
e.    None of above
Answer = A

13) The ALE line of an 8085 microprocessor is used to  ?
a.    Execute an RST by hardware
b.    Executes the instruction supplied by external device through the INTA signal
c.    Executes an instruction from memory location 20 H
d.    Executes a NOP
Answer = A
Explanation:   ALE is address latch enable. the lower order address remains only for a single T satate then ths data is latched and the lower order address bus stores the data.

14) The cost for storing a bit is minimum in ?
a.    Cache
b.    Register
c.    RAM
d.    Magnetic tape
Answer = D

15) The index register in a digital computer is used for  ?
a.    Pointing to the stack address
b.    Indirect addressing
c.    Keeping track of number of times a loop is executed
d.    Address modification
Answer = D
Explanation: An index register in a computer's CPU is a processor register used for modifying operand addresses during the run of a program, typically for doing vector/array operations.

16) After reset the CPU begins execution from the memory location ?
a.    0000H
b.    0001H
c.    FFEFH
d.    8000H
Answer = A

17) A single register to clear the lower four bits of the accumulator in 8085 assembly language is ?
a.    XRI 0FH
b.    ANI FOH
c.    XRI FOH
d.    ANI OFH

Answer = B
Explanation: ANI FOH ANDs the accumulator with immediate. F leaves the high nibble whatever it is, 0 clears the lower nibble

18) If the total number of states in the fetching and execution phases of an 8085 instruction is known to be 7; the number of machine cycles is  ?
a.    0
b.    1
c.    2
d.    3
Answer = C

19) Von Neumann architecture is ?
a.    SISD
b.    SIMD
c.    MIMD
d.    MISD
Answer = A
Explanation:  In computing, SISD (single instruction, single data) is a term referring to a computer architecture in which a single processor, a uniprocessor, executes a single instruction stream, to operate on data stored in a single memory. This corresponds to the von Neumann architecture.

20) A typical application of MIMD is?
a.    railway reservation
b.    weather forecasting
c.    matrix multiplication
d.    All of above
 
Answer = A
Explanation: MIMD (multiple instruction, multiple data) is a technique employed to achieve parallelism.