Question about jk flip-flop

Discussion in 'Homework Help' started by holybrings, Nov 14, 2007.

  1. holybrings

    Thread Starter Active Member

    Apr 4, 2007
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    How to reverse the binary counter of jk flip-flop by using switch?

    from 1>3>5>7 to 7>5>3>1
     
  2. thingmaker3

    Retired Moderator

    May 16, 2005
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  3. holybrings

    Thread Starter Active Member

    Apr 4, 2007
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    can any1 help me?
     
  4. beenthere

    Retired Moderator

    Apr 20, 2004
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    Try looking at the internal logic of an up/down counter. Why the requirement of the counter only outputting odd numbers?
     
  5. holybrings

    Thread Starter Active Member

    Apr 4, 2007
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    just an example. thanks alot. i try to search for it
     
  6. holybrings

    Thread Starter Active Member

    Apr 4, 2007
    64
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    looked through it but still cant think of it how to reverse it.
     
  7. RiJoRI

    Well-Known Member

    Aug 15, 2007
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  8. holybrings

    Thread Starter Active Member

    Apr 4, 2007
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    but how to control it by using switch?
     
  9. Papabravo

    Expert

    Feb 24, 2006
    10,179
    1,800
    The switch controls a multiplexer that selects either the true (Q) outputs, or the complement(Q-bar) outputs.
     
  10. recca02

    Senior Member

    Apr 2, 2007
    1,211
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    i was thinking the same thing but.
    for the sequence 1>3>5>7
    wont the not o/p be 6>4>2>0 and not 7>5>3>1 :confused:
    m i missing something?
     
  11. techroomt

    Senior Member

    May 19, 2004
    198
    1
    rich is right, the "Q not" outputs will count down. to get only odd outputs an lsb ff will not be used and the lsb output can just be tied high, and tied low for only even outputs.
     
  12. recca02

    Senior Member

    Apr 2, 2007
    1,211
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    got it, thanks.
    (i m learning too :rolleyes:)
     
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