[sdiy] Switch debounce

[Scott Gravenhorst]

What I see is an oscillator with an output that is basically "wire or"
connected to the switch.  This circuit can do weird things, some of them not
so good.  If NOR gate pin 4 is low, look what happens when you press the
switch - a short from Vcc through the switch through the sinking transistor
of the gate to ground.

If what you wanted was an OR or (NOR) function, this may not work and could
be destructive.

EFM...  Hmmm.

What _exactly_ is the function supposed to be?  


xyzzy at sysabend.org wrote:
>On Thu, Jan 27, 2005 at 01:18:31PM -0700, Scott Gravenhorst wrote:
>> Can you show a schematic?  
>
>http://www.themusic.net/sdiy/debounce.jpg
>
>Real dirty and simple, used everywhere.  May look familier if you've ever
>looked at the old EFM Seq2.  Values and all taken directly from the seq2 in
>fact.  To the left of the cap, lovely squarewave, to the right, very very
>short pulse.  I should have stuck a switch to disconnect the 4001's from the
>rest of the circuit, but its 2:20am and I've been in the colo facility all
>day, am coming down with the latest Monkey Death Virus, and need some sleep.
>
>Sorry for crappy looking schematic, did I mention its late?
>
>Thanks!
>
>-- 
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