question on cd4017

Discussion in 'The Projects Forum' started by forder, Nov 28, 2007.

  1. forder

    Thread Starter Member

    Sep 20, 2007
    11
    0
    hi, i have question.. can the IC cd4017 (decade counter) be used as countdown tool? i mean, i know it can count from 0 to 9. can it be implemented to count from 9 to 0?
     
  2. beenthere

    Retired Moderator

    Apr 20, 2004
    15,815
    282
    Reading data sheets can be useful. All the 4017 can do is count up.

    Of course, nothing says you can't interpret the count as decreasing.
     
  3. thingmaker3

    Retired Moderator

    May 16, 2005
    5,072
    6
    Negative logic, positive logic, its all relative.
     
  4. Ron H

    AAC Fanatic!

    Apr 14, 2005
    7,050
    657
    Since the 4017 has 10 decoded outputs (only one high at a time), is this is relevant? I can't see how. Beenthere's suggestion will work, though.
     
  5. RiJoRI

    Well-Known Member

    Aug 15, 2007
    536
    26
    So instead of tying, say, LED1 to Output1, and LED2 to Output2, and LED10 to Output10, you would tie LED10 to Output1, and LED9 to Output2, and LED10 to Output1.

    Why are the simplest solutions often the hardest to see? ;)

    --Rich
     
Loading...