Digital Logic Design Mid - I, September - 2010

1.The register AX is used as
  • offset storage
  • default counter
  • accumulator
  • none
Answer: C
2.Which of the following codes uses 7 bits to represent a character
  • ASCII
  • BCD
  • EBCIDIC
  • GRAY
Answer: A
3.If (123)5 = (X3)y then the possible values of x are
  • 4
  • 1
  • 3
  • 2
Answer: D
4.Which of the following are not weighted codes
  • Octal number
  • Decimal number
  • Excess 3 code
  • Binary number
Answer: C
5.Which of the following is not a register
  • Accumulator
  • Buffer
  • Stack pointer
  • Program counter
Answer: B
6.The first operating system used in micro processor is
  • Zenix
  • DOS
  • CP/M
  • Multics
Answer: C
7.Minimum number of Nand gates required to construct full adder
  • 9
  • 10
  • 11
  • 12
Answer: A
8.Any given Boolean expression can be implemented by using
  • Only NAND gates
  • Only NOR gates
  • Only AND gates
  • both A and B
Answer: D
9.Which of the following logic families is well suited for high speed operation
  • TTL
  • ECL
  • MOS
  • CMOS
Answer: B
10.Addressing mode used in instruction ADD X Y is
  • absolute
  • immediate
  • indirect
  • index
Answer: A
11._____________________ is used to simplify a Boolean expression
Answer: Karnaugh Map
12._____________________ architecture is not suitable for realizing SIMD.
Answer: Von Neumann
13.Addressing mode using PUSH B instruction is ________________
Answer: Register Indirect
14.ā€˜nā€™ flip flops will divide the clock frequency by a factor of _________
Answer: 2^n
15.In a positive edge triggered JK flip flop a low J and a low K produces________________
Answer: no change
16.__________ type flip flop is preferred to design a boundary counter.
Answer: D type
17.__________ is a volatile memory.
Answer: RAM
18.In __________________ only one output line will be there irrespective of any number of input lines.
Answer: Multiplexer
19.Overflow can be identified by XOR ing _______________ and _______________
Answer: Ultimate and Penultimate carry bit
20.The cost for storing a bit is minimum in ________________ memory device
Answer: Magnetic Tape