logo

CuriousTab

CuriousTab

Discussion


Home Digital Electronics Combinational Logic Circuits Comments

  • Question
  • In VHDL, data can be each of the following types except ________.


  • Options
  • A. BIT
  • B. BIT_VECTOR
  • C. STD_LOGIC
  • D. STD_VECTOR

  • Correct Answer
  • STD_VECTOR 


  • Combinational Logic Circuits problems


    Search Results


    • 1. A circuit that can convert one of ten numerical keys pressed on a keyboard to BCD is a ________.

    • Options
    • A. priority encoder
    • B. decoder
    • C. multiplexer
    • D. demultiplexer
    • Discuss
    • 2. The correct output for this XOR truth table is ________.


    • Options
    • A.
    • B.
    • C.
    • D.
    • Discuss
    • 3. The 7447A is a BCD-to-7-segment decoder with ripple blanking input and output functions. The purpose of these lines is to ________.

    • Options
    • A. turn off the display for any nonsignificant digit
    • B. turn off the display for any zero
    • C. turn off the display for leading or trailing zeros
    • D. test the display to assure all segments are operational
    • Discuss
    • 4. The ________ statement evaluates the variable status.

    • Options
    • A. IF/THEN
    • B. IF/THEN/ELSE
    • C. CASE
    • D. ELSIF
    • Discuss
    • 5. A Karnaugh map will ________.

    • Options
    • A. eliminate the need for tedious Boolean simplifications
    • B. allow any circuit to be implemented with just AND and OR gates
    • C. produce the simplest sum-of-products expression
    • D. give an overall picture of how the signals flow through the logic circuit
    • Discuss
    • 6. A 4-bit adder has the following inputs: C0 = 0, A1 = 0, A2 = 1, A3 = 0, A4 = 1, B1 = 0, B2 = 1, B3 = 1, B4 = 1. The output will be ________.

    • Options
    • A. 01100
    • B. 10101
    • C. 11000
    • D. 00011
    • Discuss
    • 7. In an odd-parity system, the data that will produce a parity bit = 1 is ________.

    • Options
    • A. data = 1010011
    • B. data = 1111000
    • C. data = 1100000
    • D. All of the above
    • Discuss
    • 8. Parity generators and checkers use ________ gates.

    • Options
    • A. exclusive-AND
    • B. exclusive-OR/NOR
    • C. exclusive-OR
    • D. exclusive-NAND
    • Discuss
    • 9. When an open occurs on the input of a TTL device, the output will ________.

    • Options
    • A. go LOW, because there is no current in an open circuit
    • B. react as if the open input were a HIGH
    • C. go HIGH, since full voltage appears across an open
    • D. still be good, if only the good inputs are used
    • Discuss
    • 10. A half-adder does not have ________.

    • Options
    • A. carry in
    • B. carry out
    • C. two inputs
    • D. all of the above
    • Discuss


    Comments

    There are no comments.

Enter a new Comment