clocking counter

Discussion in 'General Electronics Chat' started by duxbuz, Apr 18, 2014.

  1. duxbuz

    Thread Starter Member

    Feb 23, 2014
    133
    0
    I am trying to use this circuit :

    http://www.z80.info/gfx/clock.gif

    to provide clock cycles for this IC:

    http://www.farnell.com/datasheets/1758138.pdf

    I have these pins pulled down to ground:

    ~1CP1
    1MR
    2CP0
    ~2CP1
    2MR

    The outputs are all unconnected pins

    I am expecting when probing the 1Q1 1Q2 etc pins to have some change in their state as I use my SPDT switch to clock through.

    The clock signal goes low to high as expected but the state of my output pins 1Q0 etc never change from high state

    I wondered if I am missing something simple?

    Thanks
     
  2. ScottWang

    Moderator

    Aug 23, 2012
    4,853
    767
    If you wish the clock input from 1CP0, you should connecting /1CP1 to High, Low is inhibit.
     
    duxbuz likes this.
  3. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
    2,501
    380
    hi dux,
    The unclocked 'clock' pin has to be High for the clock to work.
    E
     
    duxbuz likes this.
  4. duxbuz

    Thread Starter Member

    Feb 23, 2014
    133
    0
    Wonderful

    Many thanks
     
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